From dbc6ac1e9b10131092a426413e2034782d8cd9b0 Mon Sep 17 00:00:00 2001
From: Alfonso Gregory <gfunni234@gmail.com>
Date: Sun, 25 Jul 2021 21:44:31 -0400
Subject: [PATCH 01/17] Update memchr.h

---
 libc/src/string/memchr.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libc/src/string/memchr.h b/libc/src/string/memchr.h
index 369475305236d..98246cb4ea032 100644
--- a/libc/src/string/memchr.h
+++ b/libc/src/string/memchr.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-void *memchr(const void *src, int c, size_t n);
+void *memchr(const void *src, int c, size_t n) noexcept;
 
 } // namespace __llvm_libc
 

From 162f8aebe83af1b5496cd11bad6211b6b249c12c Mon Sep 17 00:00:00 2001
From: Alfonso Gregory <83477269+gAlfonso-bit@users.noreply.github.com>
Date: Mon, 26 Jul 2021 09:44:16 -0400
Subject: [PATCH 02/17] Patch 1

---
 libc/src/__support/common.h             |  4 ++--
 libc/src/__support/integer_operations.h |  6 ++----
 libc/src/assert/__assert_fail.cpp       | 11 ++++++-----
 libc/src/string/memmove.cpp             |  2 +-
 4 files changed, 11 insertions(+), 12 deletions(-)

diff --git a/libc/src/__support/common.h b/libc/src/__support/common.h
index 53a63fc2e9173..b5cd66ae52ca9 100644
--- a/libc/src/__support/common.h
+++ b/libc/src/__support/common.h
@@ -24,9 +24,9 @@
   LLVM_LIBC_FUNCTION_ATTR decltype(__llvm_libc::name)                          \
       __##name##_impl__ __asm__(#name);                                        \
   decltype(__llvm_libc::name) name [[gnu::alias(#name)]];                      \
-  type __##name##_impl__ arglist
+  type __##name##_impl__ arglist noexcept
 #else
-#define LLVM_LIBC_FUNCTION(type, name, arglist) type name arglist
+#define LLVM_LIBC_FUNCTION(type, name, arglist) type name arglist noexcept
 #endif
 
 namespace __llvm_libc {
diff --git a/libc/src/__support/integer_operations.h b/libc/src/__support/integer_operations.h
index 733fb7ed9ce91..f52c11a4a97e7 100644
--- a/libc/src/__support/integer_operations.h
+++ b/libc/src/__support/integer_operations.h
@@ -14,10 +14,8 @@
 namespace __llvm_libc {
 
 template <typename T>
-static inline cpp::EnableIfType<cpp::IsIntegral<T>::Value, T> integerAbs(T n) {
-  if (n < 0)
-    return -n;
-  return n;
+static constexpr inline cpp::EnableIfType<cpp::IsIntegral<T>::Value, T> integerAbs(T n) {
+  return (n < 0) ? -n : n;
 }
 
 } // namespace __llvm_libc
diff --git a/libc/src/assert/__assert_fail.cpp b/libc/src/assert/__assert_fail.cpp
index 614e130276338..5ccb96dc4af47 100644
--- a/libc/src/assert/__assert_fail.cpp
+++ b/libc/src/assert/__assert_fail.cpp
@@ -18,15 +18,16 @@ namespace __llvm_libc {
 // This is just a temporary solution to make assert available to internal
 // llvm libc code. In the future writeToStderr will not exist and __assert_fail
 // will call fprintf(stderr, ...).
-static void writeToStderr(const char *s) {
+static void writeToStderr(const char *s) noexcept {
   size_t length = 0;
-  for (const char *curr = s; *curr; ++curr, ++length);
+  for (const char *curr = s; *curr; ++curr)
+    ++length;
   __llvm_libc::syscall(SYS_write, 2, s, length);
 }
 
-LLVM_LIBC_FUNCTION(void, __assert_fail,
-                   (const char *assertion, const char *file, unsigned line,
-                    const char *function)) {
+[[noreturn]] LLVM_LIBC_FUNCTION(void, __assert_fail,
+                                (const char *assertion, const char *file,
+                                 unsigned line, const char *function)) {
   writeToStderr(file);
   writeToStderr(": Assertion failed: '");
   writeToStderr(assertion);
diff --git a/libc/src/string/memmove.cpp b/libc/src/string/memmove.cpp
index ebbe4643e7da6..3e5b493e0f7f2 100644
--- a/libc/src/string/memmove.cpp
+++ b/libc/src/string/memmove.cpp
@@ -16,7 +16,7 @@
 namespace __llvm_libc {
 
 static inline void move_byte_forward(char *dest_m, const char *src_m,
-                                     size_t count) {
+                                     size_t count) noexcept {
   for (size_t offset = 0; count; --count, ++offset)
     dest_m[offset] = src_m[offset];
 }

From 59a1a0d779c249ceb4fcfe2206dbbc4df92f2a8a Mon Sep 17 00:00:00 2001
From: Alfonso Gregory <83477269+gAlfonso-bit@users.noreply.github.com>
Date: Mon, 26 Jul 2021 10:42:06 -0400
Subject: [PATCH 03/17] First batch

---
 libc/src/ctype/ctype_utils.h | 12 ++++++------
 libc/src/ctype/isalnum.cpp   |  4 +++-
 libc/src/ctype/isalpha.cpp   |  4 +++-
 libc/src/ctype/isalpha.h     |  2 +-
 libc/src/ctype/isascii.cpp   |  4 +++-
 libc/src/ctype/isascii.h     |  2 +-
 libc/src/ctype/isblank.cpp   |  3 +--
 libc/src/ctype/isblank.h     |  2 +-
 libc/src/ctype/iscntrl.cpp   |  2 +-
 libc/src/ctype/iscntrl.h     |  2 +-
 libc/src/ctype/isdigit.cpp   |  4 +++-
 libc/src/ctype/isdigit.h     |  2 +-
 libc/src/ctype/isgraph.cpp   |  4 +++-
 libc/src/ctype/isgraph.h     |  2 +-
 libc/src/ctype/islower.cpp   |  4 +++-
 libc/src/ctype/islower.h     |  2 +-
 libc/src/ctype/isprint.cpp   |  2 +-
 libc/src/ctype/isprint.h     |  2 +-
 libc/src/ctype/ispunct.cpp   |  3 ++-
 libc/src/ctype/ispunct.h     |  2 +-
 libc/src/ctype/isspace.cpp   |  2 +-
 libc/src/ctype/isspace.h     |  2 +-
 libc/src/ctype/isupper.cpp   |  4 +++-
 libc/src/ctype/isupper.h     |  2 +-
 libc/src/ctype/isxdigit.cpp  |  2 +-
 libc/src/ctype/isxdigit.h    |  2 +-
 libc/src/ctype/toascii.h     |  2 +-
 libc/src/ctype/tolower.cpp   |  2 +-
 libc/src/ctype/tolower.h     |  2 +-
 libc/src/ctype/toupper.cpp   |  2 +-
 libc/src/ctype/toupper.h     |  2 +-
 31 files changed, 51 insertions(+), 37 deletions(-)

diff --git a/libc/src/ctype/ctype_utils.h b/libc/src/ctype/ctype_utils.h
index 6238bd32d9f8c..b8457227aa832 100644
--- a/libc/src/ctype/ctype_utils.h
+++ b/libc/src/ctype/ctype_utils.h
@@ -18,17 +18,17 @@ namespace internal {
 // of a function call by inlining them.
 // ------------------------------------------------------
 
-static inline int isalpha(unsigned ch) { return (ch | 32) - 'a' < 26; }
+static constexpr int isalpha(unsigned ch) { return (ch | 32) - 'a' < 26; }
 
-static inline int isdigit(unsigned ch) { return (ch - '0') < 10; }
+static constexpr int isdigit(unsigned ch) { return (ch - '0') < 10; }
 
-static inline int isalnum(unsigned ch) { return isalpha(ch) || isdigit(ch); }
+static constexpr int isalnum(unsigned ch) { return isalpha(ch) || isdigit(ch); }
 
-static inline int isgraph(unsigned ch) { return 0x20 < ch && ch < 0x7f; }
+static constexpr int isgraph(unsigned ch) { return 0x20 < ch && ch < 0x7f; }
 
-static inline int islower(unsigned ch) { return (ch - 'a') < 26; }
+static constexpr int islower(unsigned ch) { return (ch - 'a') < 26; }
 
-static inline int isupper(unsigned ch) { return (ch - 'A') < 26; }
+static constexpr int isupper(unsigned ch) { return (ch - 'A') < 26; }
 
 } // namespace internal
 } // namespace __llvm_libc
diff --git a/libc/src/ctype/isalnum.cpp b/libc/src/ctype/isalnum.cpp
index 3e8da722c674a..aae0112adaf73 100644
--- a/libc/src/ctype/isalnum.cpp
+++ b/libc/src/ctype/isalnum.cpp
@@ -15,6 +15,8 @@ namespace __llvm_libc {
 
 // TODO: Currently restricted to default locale.
 // These should be extended using locale information.
-LLVM_LIBC_FUNCTION(int, isalnum, (int c)) { return internal::isalnum(c); }
+LLVM_LIBC_FUNCTION(int, isalnum, (int c)) {
+  return internal::isalnum(static_cast<unsigned>(c));
+}
 
 } // namespace __llvm_libc
diff --git a/libc/src/ctype/isalpha.cpp b/libc/src/ctype/isalpha.cpp
index cecf1b516939d..b019377cf5499 100644
--- a/libc/src/ctype/isalpha.cpp
+++ b/libc/src/ctype/isalpha.cpp
@@ -15,6 +15,8 @@ namespace __llvm_libc {
 
 // TODO: Currently restricted to default locale.
 // These should be extended using locale information.
-LLVM_LIBC_FUNCTION(int, isalpha, (int c)) { return internal::isalpha(c); }
+LLVM_LIBC_FUNCTION(int, isalpha, (int c)) {
+  return internal::isalpha(static_cast<unsigned>(c));
+}
 
 } // namespace __llvm_libc
diff --git a/libc/src/ctype/isalpha.h b/libc/src/ctype/isalpha.h
index d5697a39e9aa5..c1f1f9e9ed054 100644
--- a/libc/src/ctype/isalpha.h
+++ b/libc/src/ctype/isalpha.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int isalpha(int c);
+int isalpha(int c) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/ctype/isascii.cpp b/libc/src/ctype/isascii.cpp
index c12915ecd6ee3..d7f00dcd0b2e9 100644
--- a/libc/src/ctype/isascii.cpp
+++ b/libc/src/ctype/isascii.cpp
@@ -12,6 +12,8 @@
 
 namespace __llvm_libc {
 
-LLVM_LIBC_FUNCTION(int, isascii, (int c)) { return (c & (~0x7f)) == 0; }
+LLVM_LIBC_FUNCTION(int, isascii, (int c)) {
+  return static_cast<unsigned>(c) <= 0x7f;
+}
 
 } // namespace __llvm_libc
diff --git a/libc/src/ctype/isascii.h b/libc/src/ctype/isascii.h
index 7e31b3c6ca4dd..ce328f2a2467e 100644
--- a/libc/src/ctype/isascii.h
+++ b/libc/src/ctype/isascii.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-int isascii(int c);
+int isascii(int c) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/ctype/isblank.cpp b/libc/src/ctype/isblank.cpp
index 1c3061379b293..4e3d0d6297bbd 100644
--- a/libc/src/ctype/isblank.cpp
+++ b/libc/src/ctype/isblank.cpp
@@ -15,8 +15,7 @@ namespace __llvm_libc {
 // TODO: Currently restricted to default locale.
 // These should be extended using locale information.
 LLVM_LIBC_FUNCTION(int, isblank, (int c)) {
-  const unsigned char ch = static_cast<char>(c);
-  return ch == ' ' || ch == '\t';
+  return c == ' ' || c == '\t';
 }
 
 } // namespace __llvm_libc
diff --git a/libc/src/ctype/isblank.h b/libc/src/ctype/isblank.h
index 0554322d08251..ac706d60588f9 100644
--- a/libc/src/ctype/isblank.h
+++ b/libc/src/ctype/isblank.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int isblank(int c);
+int isblank(int c) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/ctype/iscntrl.cpp b/libc/src/ctype/iscntrl.cpp
index b061199c47ec5..d4a9491e1e05f 100644
--- a/libc/src/ctype/iscntrl.cpp
+++ b/libc/src/ctype/iscntrl.cpp
@@ -15,7 +15,7 @@ namespace __llvm_libc {
 // TODO: Currently restricted to default locale.
 // These should be extended using locale information.
 LLVM_LIBC_FUNCTION(int, iscntrl, (int c)) {
-  const unsigned char ch = static_cast<char>(c);
+  const unsigned ch = static_cast<unsigned>(c);
   return ch < 0x20 || ch == 0x7f;
 }
 
diff --git a/libc/src/ctype/iscntrl.h b/libc/src/ctype/iscntrl.h
index 26f094053a28a..676123e269d47 100644
--- a/libc/src/ctype/iscntrl.h
+++ b/libc/src/ctype/iscntrl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int iscntrl(int c);
+int iscntrl(int c) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/ctype/isdigit.cpp b/libc/src/ctype/isdigit.cpp
index 8471e4b5569a4..dc746860b7e21 100644
--- a/libc/src/ctype/isdigit.cpp
+++ b/libc/src/ctype/isdigit.cpp
@@ -14,6 +14,8 @@ namespace __llvm_libc {
 
 // TODO: Currently restricted to default locale.
 // These should be extended using locale information.
-LLVM_LIBC_FUNCTION(int, isdigit, (int c)) { return internal::isdigit(c); }
+LLVM_LIBC_FUNCTION(int, isdigit, (int c)) {
+  return internal::isdigit(static_cast<unsigned>(c));
+}
 
 } // namespace __llvm_libc
diff --git a/libc/src/ctype/isdigit.h b/libc/src/ctype/isdigit.h
index 32a76235e0592..a0d1aa4d8181b 100644
--- a/libc/src/ctype/isdigit.h
+++ b/libc/src/ctype/isdigit.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int isdigit(int c);
+int isdigit(int c) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/ctype/isgraph.cpp b/libc/src/ctype/isgraph.cpp
index 2bb6a57da4073..741ae96ef3c48 100644
--- a/libc/src/ctype/isgraph.cpp
+++ b/libc/src/ctype/isgraph.cpp
@@ -15,6 +15,8 @@ namespace __llvm_libc {
 
 // TODO: Currently restricted to default locale.
 // These should be extended using locale information.
-LLVM_LIBC_FUNCTION(int, isgraph, (int c)) { return internal::isgraph(c); }
+LLVM_LIBC_FUNCTION(int, isgraph, (int c)) {
+  return internal::isgraph(static_cast<unsigned>(c));
+}
 
 } // namespace __llvm_libc
diff --git a/libc/src/ctype/isgraph.h b/libc/src/ctype/isgraph.h
index 421d0ffc4488b..9eb47aa3d9372 100644
--- a/libc/src/ctype/isgraph.h
+++ b/libc/src/ctype/isgraph.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int isgraph(int c);
+int isgraph(int c) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/ctype/islower.cpp b/libc/src/ctype/islower.cpp
index 907a322174969..230b10f3f7381 100644
--- a/libc/src/ctype/islower.cpp
+++ b/libc/src/ctype/islower.cpp
@@ -15,6 +15,8 @@ namespace __llvm_libc {
 
 // TODO: Currently restricted to default locale.
 // These should be extended using locale information.
-LLVM_LIBC_FUNCTION(int, islower, (int c)) { return internal::islower(c); }
+LLVM_LIBC_FUNCTION(int, islower, (int c)) {
+  return internal::islower(static_cast<unsigned>(c));
+}
 
 } // namespace __llvm_libc
diff --git a/libc/src/ctype/islower.h b/libc/src/ctype/islower.h
index 7643542fb7a99..7905506ad05cc 100644
--- a/libc/src/ctype/islower.h
+++ b/libc/src/ctype/islower.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int islower(int c);
+int islower(int c) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/ctype/isprint.cpp b/libc/src/ctype/isprint.cpp
index a80500b133c4f..a155b95ca1ef6 100644
--- a/libc/src/ctype/isprint.cpp
+++ b/libc/src/ctype/isprint.cpp
@@ -15,7 +15,7 @@ namespace __llvm_libc {
 // TODO: Currently restricted to default locale.
 // These should be extended using locale information.
 LLVM_LIBC_FUNCTION(int, isprint, (int c)) {
-  const unsigned ch = c;
+  const unsigned ch = static_cast<unsigned>(c);
   return (ch - ' ') < 95;
 }
 
diff --git a/libc/src/ctype/isprint.h b/libc/src/ctype/isprint.h
index 17ed56ef25340..97daf4b908b1d 100644
--- a/libc/src/ctype/isprint.h
+++ b/libc/src/ctype/isprint.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int isprint(int c);
+int isprint(int c) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/ctype/ispunct.cpp b/libc/src/ctype/ispunct.cpp
index 064b7b07c6e6a..f74967201e169 100644
--- a/libc/src/ctype/ispunct.cpp
+++ b/libc/src/ctype/ispunct.cpp
@@ -16,7 +16,8 @@ namespace __llvm_libc {
 // TODO: Currently restricted to default locale.
 // These should be extended using locale information.
 LLVM_LIBC_FUNCTION(int, ispunct, (int c)) {
-  return !internal::isalnum(c) && internal::isgraph(c);
+  const unsigned ch = static_cast<unsigned>(c);
+  return !internal::isalnum(ch) && internal::isgraph(ch);
 }
 
 } // namespace __llvm_libc
diff --git a/libc/src/ctype/ispunct.h b/libc/src/ctype/ispunct.h
index 23cc08a0bac9c..265524d65711b 100644
--- a/libc/src/ctype/ispunct.h
+++ b/libc/src/ctype/ispunct.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int ispunct(int c);
+int ispunct(int c) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/ctype/isspace.cpp b/libc/src/ctype/isspace.cpp
index 4a269ef29bf2f..85bed92231185 100644
--- a/libc/src/ctype/isspace.cpp
+++ b/libc/src/ctype/isspace.cpp
@@ -15,7 +15,7 @@ namespace __llvm_libc {
 // TODO: Currently restricted to default locale.
 // These should be extended using locale information.
 LLVM_LIBC_FUNCTION(int, isspace, (int c)) {
-  const unsigned ch = c;
+  const unsigned ch = static_cast<unsigned>(c);
   return ch == ' ' || (ch - '\t') < 5;
 }
 
diff --git a/libc/src/ctype/isspace.h b/libc/src/ctype/isspace.h
index d919e9e7d972b..ef49dea7462df 100644
--- a/libc/src/ctype/isspace.h
+++ b/libc/src/ctype/isspace.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int isspace(int c);
+int isspace(int c) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/ctype/isupper.cpp b/libc/src/ctype/isupper.cpp
index f1c56fc942f68..e429dc20592ee 100644
--- a/libc/src/ctype/isupper.cpp
+++ b/libc/src/ctype/isupper.cpp
@@ -15,6 +15,8 @@ namespace __llvm_libc {
 
 // TODO: Currently restricted to default locale.
 // These should be extended using locale information.
-LLVM_LIBC_FUNCTION(int, isupper, (int c)) { return internal::isupper(c); }
+LLVM_LIBC_FUNCTION(int, isupper, (int c)) {
+  return internal::isupper(static_cast<unsigned>(c));
+}
 
 } // namespace __llvm_libc
diff --git a/libc/src/ctype/isupper.h b/libc/src/ctype/isupper.h
index 7a1f2270943a9..83a9df3044c57 100644
--- a/libc/src/ctype/isupper.h
+++ b/libc/src/ctype/isupper.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int isupper(int c);
+int isupper(int c) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/ctype/isxdigit.cpp b/libc/src/ctype/isxdigit.cpp
index 5ee1b1090b778..cf9b912ca76fc 100644
--- a/libc/src/ctype/isxdigit.cpp
+++ b/libc/src/ctype/isxdigit.cpp
@@ -16,7 +16,7 @@ namespace __llvm_libc {
 // TODO: Currently restricted to default locale.
 // These should be extended using locale information.
 LLVM_LIBC_FUNCTION(int, isxdigit, (int c)) {
-  const unsigned ch = c;
+  const unsigned ch = static_cast<unsigned>(c);
   return internal::isdigit(ch) || (ch | 32) - 'a' < 6;
 }
 
diff --git a/libc/src/ctype/isxdigit.h b/libc/src/ctype/isxdigit.h
index a332ecc1018ff..16a12c1afdd42 100644
--- a/libc/src/ctype/isxdigit.h
+++ b/libc/src/ctype/isxdigit.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int isxdigit(int c);
+int isxdigit(int c) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/ctype/toascii.h b/libc/src/ctype/toascii.h
index c3f48a38d84c9..59bac6770b844 100644
--- a/libc/src/ctype/toascii.h
+++ b/libc/src/ctype/toascii.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int toascii(int c);
+int toascii(int c) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/ctype/tolower.cpp b/libc/src/ctype/tolower.cpp
index c01f4f0ded81d..ea64d83881076 100644
--- a/libc/src/ctype/tolower.cpp
+++ b/libc/src/ctype/tolower.cpp
@@ -16,7 +16,7 @@ namespace __llvm_libc {
 // TODO: Currently restricted to default locale.
 // These should be extended using locale information.
 LLVM_LIBC_FUNCTION(int, tolower, (int c)) {
-  if (internal::isupper(c))
+  if (internal::isupper(static_cast<unsigned>(c)))
     return c + 'a' - 'A';
   return c;
 }
diff --git a/libc/src/ctype/tolower.h b/libc/src/ctype/tolower.h
index 97e675c558252..d88be0e6f9551 100644
--- a/libc/src/ctype/tolower.h
+++ b/libc/src/ctype/tolower.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int tolower(int c);
+int tolower(int c) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/ctype/toupper.cpp b/libc/src/ctype/toupper.cpp
index 254befc38f30a..fac1959d57b1e 100644
--- a/libc/src/ctype/toupper.cpp
+++ b/libc/src/ctype/toupper.cpp
@@ -16,7 +16,7 @@ namespace __llvm_libc {
 // TODO: Currently restricted to default locale.
 // These should be extended using locale information.
 LLVM_LIBC_FUNCTION(int, toupper, (int c)) {
-  if (internal::islower(c))
+  if (internal::islower(static_cast<unsigned>(c)))
     return c + 'A' - 'a';
   return c;
 }
diff --git a/libc/src/ctype/toupper.h b/libc/src/ctype/toupper.h
index a21b0cf79d955..eac891d4d5949 100644
--- a/libc/src/ctype/toupper.h
+++ b/libc/src/ctype/toupper.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int toupper(int c);
+int toupper(int c) noexcept;
 
 } // namespace __llvm_libc
 

From b565df0ded41ce4667f10cfc0601cfeb6e212ced Mon Sep 17 00:00:00 2001
From: Alfonso Gregory <83477269+gAlfonso-bit@users.noreply.github.com>
Date: Mon, 26 Jul 2021 11:08:07 -0400
Subject: [PATCH 04/17] Round 2

---
 libc/src/errno/__errno_location.h   |  2 +-
 libc/src/fenv/feclearexcept.h       |  2 +-
 libc/src/fenv/fegetenv.h            |  2 +-
 libc/src/fenv/fegetexceptflag.h     |  2 +-
 libc/src/fenv/fegetround.h          |  2 +-
 libc/src/fenv/feholdexcept.h        |  2 +-
 libc/src/fenv/feraiseexcept.h       |  2 +-
 libc/src/fenv/fesetenv.h            |  2 +-
 libc/src/fenv/fesetexceptflag.h     |  2 +-
 libc/src/fenv/fesetround.h          |  2 +-
 libc/src/fenv/fetestexcept.h        |  2 +-
 libc/src/fenv/feupdateenv.h         |  2 +-
 libc/utils/FPUtil/x86_64/FEnvImpl.h | 45 +++++++++++++++--------------
 libc/utils/FPUtil/x86_64/FMA.h      |  8 ++---
 14 files changed, 39 insertions(+), 38 deletions(-)

diff --git a/libc/src/errno/__errno_location.h b/libc/src/errno/__errno_location.h
index 20be3fcf812ae..edc98535f63ef 100644
--- a/libc/src/errno/__errno_location.h
+++ b/libc/src/errno/__errno_location.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int *__errno_location();
+int *__errno_location() noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/fenv/feclearexcept.h b/libc/src/fenv/feclearexcept.h
index fa771cee32a18..3266db3050ab7 100644
--- a/libc/src/fenv/feclearexcept.h
+++ b/libc/src/fenv/feclearexcept.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int feclearexcept(int);
+int feclearexcept(int) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/fenv/fegetenv.h b/libc/src/fenv/fegetenv.h
index e1001682a42bb..3849a9bbd88ee 100644
--- a/libc/src/fenv/fegetenv.h
+++ b/libc/src/fenv/fegetenv.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-int fegetenv(fenv_t *);
+int fegetenv(fenv_t *) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/fenv/fegetexceptflag.h b/libc/src/fenv/fegetexceptflag.h
index 20913cb7a22f8..e173b4b722cf4 100644
--- a/libc/src/fenv/fegetexceptflag.h
+++ b/libc/src/fenv/fegetexceptflag.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-int fegetexceptflag(fexcept_t *, int excepts);
+int fegetexceptflag(fexcept_t *, int excepts) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/fenv/fegetround.h b/libc/src/fenv/fegetround.h
index 1bc79cbf5a6c4..7934dea2beaf5 100644
--- a/libc/src/fenv/fegetround.h
+++ b/libc/src/fenv/fegetround.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int fegetround();
+int fegetround() noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/fenv/feholdexcept.h b/libc/src/fenv/feholdexcept.h
index cfb86b54ff49e..5ac71e1d1c65b 100644
--- a/libc/src/fenv/feholdexcept.h
+++ b/libc/src/fenv/feholdexcept.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-int feholdexcept(fenv_t *);
+int feholdexcept(fenv_t *) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/fenv/feraiseexcept.h b/libc/src/fenv/feraiseexcept.h
index 5c9eacf462d49..446b255243eba 100644
--- a/libc/src/fenv/feraiseexcept.h
+++ b/libc/src/fenv/feraiseexcept.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int feraiseexcept(int);
+int feraiseexcept(int) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/fenv/fesetenv.h b/libc/src/fenv/fesetenv.h
index 316ecee41996e..fc6d612f193a2 100644
--- a/libc/src/fenv/fesetenv.h
+++ b/libc/src/fenv/fesetenv.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-int fesetenv(const fenv_t *);
+int fesetenv(const fenv_t *) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/fenv/fesetexceptflag.h b/libc/src/fenv/fesetexceptflag.h
index 0e6497abafaed..05dfe59a8e54b 100644
--- a/libc/src/fenv/fesetexceptflag.h
+++ b/libc/src/fenv/fesetexceptflag.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-int fesetexceptflag(const fexcept_t *, int excepts);
+int fesetexceptflag(const fexcept_t *, int excepts) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/fenv/fesetround.h b/libc/src/fenv/fesetround.h
index 148a5eabcf3d5..6ad8c24f045d6 100644
--- a/libc/src/fenv/fesetround.h
+++ b/libc/src/fenv/fesetround.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int fesetround(int);
+int fesetround(int) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/fenv/fetestexcept.h b/libc/src/fenv/fetestexcept.h
index fb3e4045dd6b0..f67796343ae63 100644
--- a/libc/src/fenv/fetestexcept.h
+++ b/libc/src/fenv/fetestexcept.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int fetestexcept(int);
+int fetestexcept(int) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/fenv/feupdateenv.h b/libc/src/fenv/feupdateenv.h
index 1599c01ebddff..9e2d6cec67e69 100644
--- a/libc/src/fenv/feupdateenv.h
+++ b/libc/src/fenv/feupdateenv.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-int feupdateenv(const fenv_t *);
+int feupdateenv(const fenv_t *) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/utils/FPUtil/x86_64/FEnvImpl.h b/libc/utils/FPUtil/x86_64/FEnvImpl.h
index fae74bb5da9bc..f628d3211bb4b 100644
--- a/libc/utils/FPUtil/x86_64/FEnvImpl.h
+++ b/libc/utils/FPUtil/x86_64/FEnvImpl.h
@@ -61,7 +61,7 @@ static constexpr uint16_t MXCSRExceptionContolBitPoistion = 7;
 
 // Exception flags are individual bits in the corresponding registers.
 // So, we just OR the bit values to get the full set of exceptions.
-static inline uint16_t getStatusValueForExcept(int excepts) {
+static constexpr uint16_t getStatusValueForExcept(int excepts) {
   // We will make use of the fact that exception control bits are single
   // bit flags in the control registers.
   return (excepts & FE_INVALID ? ExceptionFlags::Invalid : 0) |
@@ -74,7 +74,7 @@ static inline uint16_t getStatusValueForExcept(int excepts) {
          (excepts & FE_INEXACT ? ExceptionFlags::Inexact : 0);
 }
 
-static inline int exceptionStatusToMacro(uint16_t status) {
+static constexpr int exceptionStatusToMacro(uint16_t status) {
   return (status & ExceptionFlags::Invalid ? FE_INVALID : 0) |
 #ifdef __FE_DENORM
          (status & ExceptionFlags::Denormal ? __FE_DENORM : 0) |
@@ -107,53 +107,54 @@ static_assert(
     sizeof(fenv_t) == sizeof(FPState),
     "Internal floating point state does not match the public fenv_t type.");
 
-static inline uint16_t getX87ControlWord() {
+static inline uint16_t getX87ControlWord() noexcept {
   uint16_t w;
   __asm__ __volatile__("fnstcw %0" : "=m"(w)::);
   SANITIZER_MEMORY_INITIALIZED(&w, sizeof(w));
   return w;
 }
 
-static inline void writeX87ControlWord(uint16_t w) {
+static inline void writeX87ControlWord(uint16_t w) noexcept {
   __asm__ __volatile__("fldcw %0" : : "m"(w) :);
 }
 
-static inline uint16_t getX87StatusWord() {
+static inline uint16_t getX87StatusWord() noexcept {
   uint16_t w;
   __asm__ __volatile__("fnstsw %0" : "=m"(w)::);
   SANITIZER_MEMORY_INITIALIZED(&w, sizeof(w));
   return w;
 }
 
-static inline void clearX87Exceptions() {
+static inline void clearX87Exceptions() noexcept {
   __asm__ __volatile__("fnclex" : : :);
 }
 
-static inline uint32_t getMXCSR() {
+static inline uint32_t getMXCSR() noexcept {
   uint32_t w;
   __asm__ __volatile__("stmxcsr %0" : "=m"(w)::);
   SANITIZER_MEMORY_INITIALIZED(&w, sizeof(w));
   return w;
 }
 
-static inline void writeMXCSR(uint32_t w) {
+static inline void writeMXCSR(uint32_t w) noexcept {
   __asm__ __volatile__("ldmxcsr %0" : : "m"(w) :);
 }
 
-static inline void getX87StateDescriptor(X87StateDescriptor &s) {
+static inline void getX87StateDescriptor(X87StateDescriptor &s) noexcept {
   __asm__ __volatile__("fnstenv %0" : "=m"(s));
   SANITIZER_MEMORY_INITIALIZED(&s, sizeof(s));
 }
 
-static inline void writeX87StateDescriptor(const X87StateDescriptor &s) {
+static inline void
+writeX87StateDescriptor(const X87StateDescriptor &s) noexcept {
   __asm__ __volatile__("fldenv %0" : : "m"(s) :);
 }
 
-static inline void fwait() { __asm__ __volatile__("fwait"); }
+static inline void fwait() noexcept { __asm__ __volatile__("fwait"); }
 
 } // namespace internal
 
-static inline int enableExcept(int excepts) {
+static inline int enableExcept(int excepts) noexcept {
   // In the x87 control word and in MXCSR, an exception is blocked
   // if the corresponding bit is set. That is the reason for all the
   // bit-flip operations below as we need to turn the bits to zero
@@ -180,7 +181,7 @@ static inline int enableExcept(int excepts) {
   return internal::exceptionStatusToMacro(oldExcepts);
 }
 
-static inline int disableExcept(int excepts) {
+static inline int disableExcept(int excepts) noexcept {
   // In the x87 control word and in MXCSR, an exception is blocked
   // if the corresponding bit is set.
 
@@ -200,7 +201,7 @@ static inline int disableExcept(int excepts) {
   return internal::exceptionStatusToMacro(oldExcepts);
 }
 
-static inline int clearExcept(int excepts) {
+static inline int clearExcept(int excepts) noexcept {
   internal::X87StateDescriptor state;
   internal::getX87StateDescriptor(state);
   state.StatusWord &= ~internal::getStatusValueForExcept(excepts);
@@ -212,7 +213,7 @@ static inline int clearExcept(int excepts) {
   return 0;
 }
 
-static inline int testExcept(int excepts) {
+static inline int testExcept(int excepts) noexcept {
   uint16_t statusValue = internal::getStatusValueForExcept(excepts);
   // Check both x87 status word and MXCSR.
   return internal::exceptionStatusToMacro(
@@ -221,7 +222,7 @@ static inline int testExcept(int excepts) {
 }
 
 // Sets the exception flags but does not trigger the exception handler.
-static inline int setExcept(int excepts) {
+static inline int setExcept(int excepts) noexcept {
   uint16_t statusValue = internal::getStatusValueForExcept(excepts);
   internal::X87StateDescriptor state;
   internal::getX87StateDescriptor(state);
@@ -235,7 +236,7 @@ static inline int setExcept(int excepts) {
   return 0;
 }
 
-static inline int raiseExcept(int excepts) {
+static inline int raiseExcept(int excepts) noexcept {
   uint16_t statusValue = internal::getStatusValueForExcept(excepts);
 
   // We set the status flag for exception one at a time and call the
@@ -251,7 +252,7 @@ static inline int raiseExcept(int excepts) {
   // ensure that the writes by the exception handler are maintained
   // when raising the next exception.
 
-  auto raiseHelper = [](uint16_t  singleExceptFlag) {
+  auto raiseHelper = [](uint16_t singleExceptFlag) {
     internal::X87StateDescriptor state;
     internal::getX87StateDescriptor(state);
     state.StatusWord |= singleExceptFlag;
@@ -283,7 +284,7 @@ static inline int raiseExcept(int excepts) {
   return 0;
 }
 
-static inline int getRound() {
+static inline int getRound() noexcept {
   uint16_t bitValue =
       (internal::getMXCSR() >> internal::MXCSRRoundingControlBitPosition) & 0x3;
   switch (bitValue) {
@@ -300,7 +301,7 @@ static inline int getRound() {
   }
 }
 
-static inline int setRound(int mode) {
+static inline int setRound(int mode) noexcept {
   uint16_t bitValue;
   switch (mode) {
   case FE_TONEAREST:
@@ -339,14 +340,14 @@ static inline int setRound(int mode) {
 }
 
 #if !(defined(_WIN32))
-static inline int getEnv(fenv_t *envp) {
+static inline int getEnv(fenv_t *envp) noexcept {
   internal::FPState *state = reinterpret_cast<internal::FPState *>(envp);
   internal::getX87StateDescriptor(state->X87Status);
   state->MXCSR = internal::getMXCSR();
   return 0;
 }
 
-static inline int setEnv(const fenv_t *envp) {
+static inline int setEnv(const fenv_t *envp) noexcept {
   const internal::FPState *state =
       reinterpret_cast<const internal::FPState *>(envp);
   internal::writeX87StateDescriptor(state->X87Status);
diff --git a/libc/utils/FPUtil/x86_64/FMA.h b/libc/utils/FPUtil/x86_64/FMA.h
index e1bc806e4ac8b..0f38e837cbca5 100644
--- a/libc/utils/FPUtil/x86_64/FMA.h
+++ b/libc/utils/FPUtil/x86_64/FMA.h
@@ -15,8 +15,8 @@ namespace __llvm_libc {
 namespace fputil {
 
 template <typename T>
-static inline cpp::EnableIfType<cpp::IsSame<T, float>::Value, T> fma(T x, T y,
-                                                                     T z) {
+static inline cpp::EnableIfType<cpp::IsSame<T, float>::Value, T>
+fma(T x, T y, T z) noexcept {
   float result = x;
   __asm__ __volatile__("vfmadd213ss %x2, %x1, %x0"
                        : "+x"(result)
@@ -25,8 +25,8 @@ static inline cpp::EnableIfType<cpp::IsSame<T, float>::Value, T> fma(T x, T y,
 }
 
 template <typename T>
-static inline cpp::EnableIfType<cpp::IsSame<T, double>::Value, T> fma(T x, T y,
-                                                                      T z) {
+static inline cpp::EnableIfType<cpp::IsSame<T, double>::Value, T>
+fma(T x, T y, T z) noexcept {
   double result = x;
   __asm__ __volatile__("vfmadd213sd %x2, %x1, %x0"
                        : "+x"(result)

From ca034214fcc63fe50d909dacb909fc51a7960b32 Mon Sep 17 00:00:00 2001
From: Alfonso Gregory <83477269+gAlfonso-bit@users.noreply.github.com>
Date: Mon, 26 Jul 2021 11:24:49 -0400
Subject: [PATCH 05/17] math

---
 libc/src/math/ceil.h                  |  2 +-
 libc/src/math/ceilf.h                 |  2 +-
 libc/src/math/ceill.h                 |  2 +-
 libc/src/math/copysign.h              |  2 +-
 libc/src/math/copysignf.h             |  2 +-
 libc/src/math/copysignl.h             |  2 +-
 libc/src/math/cos.h                   |  2 +-
 libc/src/math/cosf.h                  |  2 +-
 libc/src/math/exp2f.h                 |  2 +-
 libc/src/math/expf.h                  |  2 +-
 libc/src/math/expm1f.h                |  2 +-
 libc/src/math/fabs.h                  |  2 +-
 libc/src/math/fabsf.h                 |  2 +-
 libc/src/math/fabsl.h                 |  2 +-
 libc/src/math/fdim.h                  |  2 +-
 libc/src/math/fdimf.h                 |  2 +-
 libc/src/math/fdiml.h                 |  2 +-
 libc/src/math/floor.h                 |  2 +-
 libc/src/math/floorf.h                |  2 +-
 libc/src/math/floorl.h                |  2 +-
 libc/src/math/fma.h                   |  2 +-
 libc/src/math/fmaf.h                  |  2 +-
 libc/src/math/fmax.h                  |  2 +-
 libc/src/math/fmaxf.h                 |  2 +-
 libc/src/math/fmaxl.h                 |  2 +-
 libc/src/math/fmin.h                  |  2 +-
 libc/src/math/fminf.h                 |  2 +-
 libc/src/math/fminl.h                 |  2 +-
 libc/src/math/frexp.h                 |  2 +-
 libc/src/math/frexpf.h                |  2 +-
 libc/src/math/frexpl.h                |  2 +-
 libc/src/math/generic/math_utils.h    | 34 ++++++++++++++++-----------
 libc/src/math/generic/sincosf_utils.h | 12 ++++++----
 libc/src/math/hypot.h                 |  2 +-
 libc/src/math/hypotf.h                |  2 +-
 libc/src/math/ilogb.h                 |  2 +-
 libc/src/math/ilogbf.h                |  2 +-
 libc/src/math/ilogbl.h                |  2 +-
 libc/src/math/ldexp.h                 |  2 +-
 libc/src/math/ldexpf.h                |  2 +-
 libc/src/math/ldexpl.h                |  2 +-
 libc/src/math/llrint.h                |  2 +-
 libc/src/math/llrintf.h               |  2 +-
 libc/src/math/llrintl.h               |  2 +-
 libc/src/math/llround.h               |  2 +-
 libc/src/math/llroundf.h              |  2 +-
 libc/src/math/llroundl.h              |  2 +-
 libc/src/math/logb.h                  |  2 +-
 libc/src/math/logbf.h                 |  2 +-
 libc/src/math/logbl.h                 |  2 +-
 libc/src/math/lrint.h                 |  2 +-
 libc/src/math/lrintf.h                |  2 +-
 libc/src/math/lrintl.h                |  2 +-
 libc/src/math/lround.h                |  2 +-
 libc/src/math/lroundf.h               |  2 +-
 libc/src/math/lroundl.h               |  2 +-
 libc/src/math/modf.h                  |  2 +-
 libc/src/math/modff.h                 |  2 +-
 libc/src/math/modfl.h                 |  2 +-
 libc/src/math/nearbyint.h             |  2 +-
 libc/src/math/nearbyintf.h            |  2 +-
 libc/src/math/nearbyintl.h            |  2 +-
 libc/src/math/nextafter.h             |  2 +-
 libc/src/math/nextafterf.h            |  2 +-
 libc/src/math/nextafterl.h            |  2 +-
 libc/src/math/remainder.h             |  2 +-
 libc/src/math/remainderf.h            |  2 +-
 libc/src/math/remainderl.h            |  2 +-
 libc/src/math/remquo.h                |  2 +-
 libc/src/math/remquof.h               |  2 +-
 libc/src/math/remquol.h               |  2 +-
 libc/src/math/rint.h                  |  2 +-
 libc/src/math/rintf.h                 |  2 +-
 libc/src/math/rintl.h                 |  2 +-
 libc/src/math/round.h                 |  2 +-
 libc/src/math/roundf.h                |  2 +-
 libc/src/math/roundl.h                |  2 +-
 libc/src/math/sin.h                   |  2 +-
 libc/src/math/sincosf.h               |  2 +-
 libc/src/math/sinf.h                  |  2 +-
 libc/src/math/sqrt.h                  |  2 +-
 libc/src/math/sqrtf.h                 |  2 +-
 libc/src/math/sqrtl.h                 |  2 +-
 libc/src/math/tan.h                   |  2 +-
 libc/src/math/trunc.h                 |  2 +-
 libc/src/math/truncf.h                |  2 +-
 libc/src/math/truncl.h                |  2 +-
 87 files changed, 112 insertions(+), 104 deletions(-)

diff --git a/libc/src/math/ceil.h b/libc/src/math/ceil.h
index 98188de20e405..b1a7e9b0fb70a 100644
--- a/libc/src/math/ceil.h
+++ b/libc/src/math/ceil.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double ceil(double x);
+double ceil(double x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/ceilf.h b/libc/src/math/ceilf.h
index e8e64565052a6..6f2add587808d 100644
--- a/libc/src/math/ceilf.h
+++ b/libc/src/math/ceilf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float ceilf(float x);
+float ceilf(float x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/ceill.h b/libc/src/math/ceill.h
index 8bf4c565c7d3b..22184f4b55e3d 100644
--- a/libc/src/math/ceill.h
+++ b/libc/src/math/ceill.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double ceill(long double x);
+long double ceill(long double x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/copysign.h b/libc/src/math/copysign.h
index edffe1b082fe0..21929390c36e2 100644
--- a/libc/src/math/copysign.h
+++ b/libc/src/math/copysign.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double copysign(double x, double y);
+double copysign(double x, double y) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/copysignf.h b/libc/src/math/copysignf.h
index 5b7f1132252d6..5affaa796553a 100644
--- a/libc/src/math/copysignf.h
+++ b/libc/src/math/copysignf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float copysignf(float x, float y);
+float copysignf(float x, float y) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/copysignl.h b/libc/src/math/copysignl.h
index 4f48323c70141..e815c52708d38 100644
--- a/libc/src/math/copysignl.h
+++ b/libc/src/math/copysignl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double copysignl(long double x, long double y);
+long double copysignl(long double x, long double y) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/cos.h b/libc/src/math/cos.h
index aca1d6d1e2281..71cb5504caabb 100644
--- a/libc/src/math/cos.h
+++ b/libc/src/math/cos.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double cos(double x);
+double cos(double x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/cosf.h b/libc/src/math/cosf.h
index 1aaabe900ba88..f1b2e4f8b4a9a 100644
--- a/libc/src/math/cosf.h
+++ b/libc/src/math/cosf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float cosf(float x);
+float cosf(float x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/exp2f.h b/libc/src/math/exp2f.h
index c1f72b1b80fa8..9a7496d693331 100644
--- a/libc/src/math/exp2f.h
+++ b/libc/src/math/exp2f.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float exp2f(float x);
+float exp2f(float x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/expf.h b/libc/src/math/expf.h
index c61ce98e9ddcf..6dc96333d3d66 100644
--- a/libc/src/math/expf.h
+++ b/libc/src/math/expf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float expf(float x);
+float expf(float x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/expm1f.h b/libc/src/math/expm1f.h
index 2577e4a492980..d52fc9e1497e8 100644
--- a/libc/src/math/expm1f.h
+++ b/libc/src/math/expm1f.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float expm1f(float x);
+float expm1f(float x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/fabs.h b/libc/src/math/fabs.h
index 424d2e01646b0..e4894213e90bc 100644
--- a/libc/src/math/fabs.h
+++ b/libc/src/math/fabs.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double fabs(double x);
+double fabs(double x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/fabsf.h b/libc/src/math/fabsf.h
index 0ad97a027c6c8..0379397f9a95c 100644
--- a/libc/src/math/fabsf.h
+++ b/libc/src/math/fabsf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float fabsf(float x);
+float fabsf(float x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/fabsl.h b/libc/src/math/fabsl.h
index fa25b1ab564d7..5625dea600184 100644
--- a/libc/src/math/fabsl.h
+++ b/libc/src/math/fabsl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double fabsl(long double x);
+long double fabsl(long double x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/fdim.h b/libc/src/math/fdim.h
index f838c121e291c..1dbabb3e2980a 100644
--- a/libc/src/math/fdim.h
+++ b/libc/src/math/fdim.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double fdim(double x, double y);
+double fdim(double x, double y) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/fdimf.h b/libc/src/math/fdimf.h
index 50c586c49cc39..8e5a650875efb 100644
--- a/libc/src/math/fdimf.h
+++ b/libc/src/math/fdimf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float fdimf(float x, float y);
+float fdimf(float x, float y) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/fdiml.h b/libc/src/math/fdiml.h
index 6de261fe861a0..36b936054ec4c 100644
--- a/libc/src/math/fdiml.h
+++ b/libc/src/math/fdiml.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double fdiml(long double x, long double y);
+long double fdiml(long double x, long double y) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/floor.h b/libc/src/math/floor.h
index 88a76ebf7d805..7542f0f184f05 100644
--- a/libc/src/math/floor.h
+++ b/libc/src/math/floor.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double floor(double x);
+double floor(double x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/floorf.h b/libc/src/math/floorf.h
index 029df3ac5c9fe..2e4be43a63265 100644
--- a/libc/src/math/floorf.h
+++ b/libc/src/math/floorf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float floorf(float x);
+float floorf(float x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/floorl.h b/libc/src/math/floorl.h
index 224cc13ec6fa6..96895f54438d1 100644
--- a/libc/src/math/floorl.h
+++ b/libc/src/math/floorl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double floorl(long double x);
+long double floorl(long double x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/fma.h b/libc/src/math/fma.h
index fbc7f09ee2c74..f8346f604ba70 100644
--- a/libc/src/math/fma.h
+++ b/libc/src/math/fma.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double fma(double x, double y, double z);
+double fma(double x, double y, double z) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/fmaf.h b/libc/src/math/fmaf.h
index 48fbb65d66506..89463d4999595 100644
--- a/libc/src/math/fmaf.h
+++ b/libc/src/math/fmaf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float fmaf(float x, float y, float z);
+float fmaf(float x, float y, float z) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/fmax.h b/libc/src/math/fmax.h
index 9f057983d28bb..b9697c8ecb8b7 100644
--- a/libc/src/math/fmax.h
+++ b/libc/src/math/fmax.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double fmax(double x, double y);
+double fmax(double x, double y) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/fmaxf.h b/libc/src/math/fmaxf.h
index e37df5cf9565d..dfaebf014f40c 100644
--- a/libc/src/math/fmaxf.h
+++ b/libc/src/math/fmaxf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float fmaxf(float x, float y);
+float fmaxf(float x, float y) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/fmaxl.h b/libc/src/math/fmaxl.h
index 41d80ba4aa52c..78f52a8893de8 100644
--- a/libc/src/math/fmaxl.h
+++ b/libc/src/math/fmaxl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double fmaxl(long double x, long double y);
+long double fmaxl(long double x, long double y) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/fmin.h b/libc/src/math/fmin.h
index 52334ee8e4560..15c967f68120c 100644
--- a/libc/src/math/fmin.h
+++ b/libc/src/math/fmin.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double fmin(double x, double y);
+double fmin(double x, double y) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/fminf.h b/libc/src/math/fminf.h
index 62dad57d852aa..cf30993743874 100644
--- a/libc/src/math/fminf.h
+++ b/libc/src/math/fminf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float fminf(float x, float y);
+float fminf(float x, float y) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/fminl.h b/libc/src/math/fminl.h
index c19505c018283..eae2d0d607e51 100644
--- a/libc/src/math/fminl.h
+++ b/libc/src/math/fminl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double fminl(long double x, long double y);
+long double fminl(long double x, long double y) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/frexp.h b/libc/src/math/frexp.h
index 9258243188360..71fe10fd1532c 100644
--- a/libc/src/math/frexp.h
+++ b/libc/src/math/frexp.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double frexp(double x, int *exp);
+double frexp(double x, int *exp) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/frexpf.h b/libc/src/math/frexpf.h
index ed303d2c76dd5..534effa24b2e9 100644
--- a/libc/src/math/frexpf.h
+++ b/libc/src/math/frexpf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float frexpf(float x, int *exp);
+float frexpf(float x, int *exp) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/frexpl.h b/libc/src/math/frexpl.h
index 9f75c82b9034a..e5e96494a2b8f 100644
--- a/libc/src/math/frexpl.h
+++ b/libc/src/math/frexpl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double frexpl(long double x, int *exp);
+long double frexpl(long double x, int *exp) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/generic/math_utils.h b/libc/src/math/generic/math_utils.h
index 4afddb04d6e43..e96b36f3e974c 100644
--- a/libc/src/math/generic/math_utils.h
+++ b/libc/src/math/generic/math_utils.h
@@ -18,25 +18,29 @@
 
 namespace __llvm_libc {
 
-static inline uint32_t as_uint32_bits(float x) {
+static inline uint32_t as_uint32_bits(float x) noexcept {
   return *reinterpret_cast<uint32_t *>(&x);
 }
 
-static inline uint64_t as_uint64_bits(double x) {
+static inline uint64_t as_uint64_bits(double x) noexcept {
   return *reinterpret_cast<uint64_t *>(&x);
 }
 
-static inline float as_float(uint32_t x) {
+static inline float as_float(uint32_t x) noexcept {
   return *reinterpret_cast<float *>(&x);
 }
 
-static inline double as_double(uint64_t x) {
+static inline double as_double(uint64_t x) noexcept {
   return *reinterpret_cast<double *>(&x);
 }
 
-static inline uint32_t top12_bits(float x) { return as_uint32_bits(x) >> 20; }
+static inline uint32_t top12_bits(float x) noexcept {
+  return as_uint32_bits(x) >> 20;
+}
 
-static inline uint32_t top12_bits(double x) { return as_uint64_bits(x) >> 52; }
+static inline uint32_t top12_bits(double x) noexcept {
+  return as_uint64_bits(x) >> 52;
+}
 
 // Values to trigger underflow and overflow.
 template <typename T> struct XFlowValues;
@@ -53,17 +57,17 @@ template <> struct XFlowValues<double> {
   static const double may_underflow_value;
 };
 
-template <typename T> static inline T with_errno(T x, int err) {
+template <typename T> static inline T with_errno(T x, int err) noexcept {
   if (math_errhandling & MATH_ERRNO)
     errno = err; // NOLINT
   return x;
 }
 
-template <typename T> static inline void force_eval(T x) {
+template <typename T> static inline void force_eval(T x) noexcept {
   volatile T y UNUSED = x;
 }
 
-template <typename T> static inline T opt_barrier(T x) {
+template <typename T> static inline T opt_barrier(T x) noexcept {
   volatile T y = x;
   return y;
 }
@@ -77,28 +81,30 @@ template <typename T>
 using EnableIfFloatOrDouble = cpp::EnableIfType<IsFloatOrDouble<T>::Value, int>;
 
 template <typename T, EnableIfFloatOrDouble<T> = 0>
-T xflow(uint32_t sign, T y) {
+T xflow(uint32_t sign, T y) noexcept {
   // Underflow happens when two extremely small values are multiplied.
   // Likewise, overflow happens when two large values are multiplied.
   y = opt_barrier(sign ? -y : y) * y;
   return with_errno(y, ERANGE);
 }
 
-template <typename T, EnableIfFloatOrDouble<T> = 0> T overflow(uint32_t sign) {
+template <typename T, EnableIfFloatOrDouble<T> = 0>
+T overflow(uint32_t sign) noexcept {
   return xflow(sign, XFlowValues<T>::overflow_value);
 }
 
-template <typename T, EnableIfFloatOrDouble<T> = 0> T underflow(uint32_t sign) {
+template <typename T, EnableIfFloatOrDouble<T> = 0>
+T underflow(uint32_t sign) noexcept {
   return xflow(sign, XFlowValues<T>::underflow_value);
 }
 
 template <typename T, EnableIfFloatOrDouble<T> = 0>
-T may_underflow(uint32_t sign) {
+T may_underflow(uint32_t sign) noexcept {
   return xflow(sign, XFlowValues<T>::may_underflow_value);
 }
 
 template <typename T, EnableIfFloatOrDouble<T> = 0>
-static inline constexpr float invalid(T x) {
+static constexpr float invalid(T x) {
   T y = (x - x) / (x - x);
   return isnan(x) ? y : with_errno(y, EDOM);
 }
diff --git a/libc/src/math/generic/sincosf_utils.h b/libc/src/math/generic/sincosf_utils.h
index 8c54cb9c1d904..a6fbb18a9214e 100644
--- a/libc/src/math/generic/sincosf_utils.h
+++ b/libc/src/math/generic/sincosf_utils.h
@@ -36,7 +36,7 @@ extern const sincos_t __sincosf_table[2];
 extern const uint32_t __inv_pio4[];
 
 // Top 12 bits of the float representation with the sign bit cleared.
-static inline uint32_t abstop12(float x) {
+static inline uint32_t abstop12(float x) noexcept {
   return (as_uint32_bits(x) >> 20) & 0x7ff;
 }
 
@@ -44,7 +44,7 @@ static inline uint32_t abstop12(float x) {
 // polynomial P and store the results in SINP and COSP. N is the quadrant,
 // if odd the cosine and sine polynomials are swapped.
 static inline void sincosf_poly(double x, double x2, const sincos_t *p, int n,
-                                float *sinp, float *cosp) {
+                                float *sinp, float *cosp) noexcept {
   double x3, x4, x5, x6, s, c, c1, c2, s1;
 
   x4 = x2 * x2;
@@ -70,7 +70,8 @@ static inline void sincosf_poly(double x, double x2, const sincos_t *p, int n,
 
 // Return the sine of inputs X and X2 (X squared) using the polynomial P.
 // N is the quadrant, and if odd the cosine polynomial is used.
-static inline float sinf_poly(double x, double x2, const sincos_t *p, int n) {
+static inline float sinf_poly(double x, double x2, const sincos_t *p,
+                              int n) noexcept {
   double x3, x4, x6, x7, s, c, c1, c2, s1;
 
   if ((n & 1) == 0) {
@@ -98,7 +99,8 @@ static inline float sinf_poly(double x, double x2, const sincos_t *p, int n) {
 // The values for PI/2 and 2/PI are accessed via P. Since PI/2 as a double
 // is accurate to 55 bits and the worst-case cancellation happens at 6 * PI/4,
 // the result is accurate for |X| <= 120.0.
-static inline double reduce_fast(double x, const sincos_t *p, int *np) {
+static inline double reduce_fast(double x, const sincos_t *p,
+                                 int *np) noexcept {
   double r;
   // Use scaled float to int conversion with explicit rounding.
   // hpi_inv is prescaled by 2^24 so the quadrant ends up in bits 24..31.
@@ -116,7 +118,7 @@ static inline double reduce_fast(double x, const sincos_t *p, int *np) {
 // multiply computes the exact 2.62-bit fixed-point modulo. Since the result
 // can have at most 29 leading zeros after the binary point, the double
 // precision result is accurate to 33 bits.
-static inline double reduce_large(uint32_t xi, int *np) {
+static inline double reduce_large(uint32_t xi, int *np) noexcept {
   const uint32_t *arr = &__inv_pio4[(xi >> 26) & 15];
   int shift = (xi >> 23) & 7;
   uint64_t n, res0, res1, res2;
diff --git a/libc/src/math/hypot.h b/libc/src/math/hypot.h
index 6c901ee8f4c0c..5778813123a59 100644
--- a/libc/src/math/hypot.h
+++ b/libc/src/math/hypot.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double hypot(double x, double y);
+double hypot(double x, double y) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/hypotf.h b/libc/src/math/hypotf.h
index 084fd7f3ef814..a64fa211477ab 100644
--- a/libc/src/math/hypotf.h
+++ b/libc/src/math/hypotf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float hypotf(float x, float y);
+float hypotf(float x, float y) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/ilogb.h b/libc/src/math/ilogb.h
index 96672077865a9..951dd44d30837 100644
--- a/libc/src/math/ilogb.h
+++ b/libc/src/math/ilogb.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int ilogb(double x);
+int ilogb(double x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/ilogbf.h b/libc/src/math/ilogbf.h
index 1afb76a107c1c..d84c64f23b489 100644
--- a/libc/src/math/ilogbf.h
+++ b/libc/src/math/ilogbf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int ilogbf(float x);
+int ilogbf(float x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/ilogbl.h b/libc/src/math/ilogbl.h
index 4d1cc1995341b..24d9c5cb0da10 100644
--- a/libc/src/math/ilogbl.h
+++ b/libc/src/math/ilogbl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int ilogbl(long double x);
+int ilogbl(long double x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/ldexp.h b/libc/src/math/ldexp.h
index 74f9a600666fa..6a3f486102037 100644
--- a/libc/src/math/ldexp.h
+++ b/libc/src/math/ldexp.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double ldexp(double x, int exp);
+double ldexp(double x, int exp) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/ldexpf.h b/libc/src/math/ldexpf.h
index f30d60155f1fd..9a79f0cfda724 100644
--- a/libc/src/math/ldexpf.h
+++ b/libc/src/math/ldexpf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float ldexpf(float x, int exp);
+float ldexpf(float x, int exp) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/ldexpl.h b/libc/src/math/ldexpl.h
index bf8435b1a21d8..ac1c6664d45d9 100644
--- a/libc/src/math/ldexpl.h
+++ b/libc/src/math/ldexpl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double ldexpl(long double x, int exp);
+long double ldexpl(long double x, int exp) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/llrint.h b/libc/src/math/llrint.h
index 96bd7b8cc9e1c..8a9c37022c22e 100644
--- a/libc/src/math/llrint.h
+++ b/libc/src/math/llrint.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long long llrint(double x);
+long long llrint(double x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/llrintf.h b/libc/src/math/llrintf.h
index eecf380f5e94d..eedd748c15c78 100644
--- a/libc/src/math/llrintf.h
+++ b/libc/src/math/llrintf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long long llrintf(float x);
+long long llrintf(float x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/llrintl.h b/libc/src/math/llrintl.h
index 94dfba7080aa9..e6e5d46edf6a4 100644
--- a/libc/src/math/llrintl.h
+++ b/libc/src/math/llrintl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long long llrintl(long double x);
+long long llrintl(long double x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/llround.h b/libc/src/math/llround.h
index 5b2b7fc96df87..eae50a7d37dd7 100644
--- a/libc/src/math/llround.h
+++ b/libc/src/math/llround.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long long llround(double x);
+long long llround(double x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/llroundf.h b/libc/src/math/llroundf.h
index 65faad1e07a61..b65a8ddc0a285 100644
--- a/libc/src/math/llroundf.h
+++ b/libc/src/math/llroundf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long long llroundf(float x);
+long long llroundf(float x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/llroundl.h b/libc/src/math/llroundl.h
index f859485a730bd..7cdf620746b24 100644
--- a/libc/src/math/llroundl.h
+++ b/libc/src/math/llroundl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long long llroundl(long double x);
+long long llroundl(long double x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/logb.h b/libc/src/math/logb.h
index b875dcd702bab..6debaa8923632 100644
--- a/libc/src/math/logb.h
+++ b/libc/src/math/logb.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double logb(double x);
+double logb(double x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/logbf.h b/libc/src/math/logbf.h
index 46dcd3c91d628..7225b0252ad04 100644
--- a/libc/src/math/logbf.h
+++ b/libc/src/math/logbf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float logbf(float x);
+float logbf(float x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/logbl.h b/libc/src/math/logbl.h
index 3630e52c92d29..07d2aa6f83801 100644
--- a/libc/src/math/logbl.h
+++ b/libc/src/math/logbl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double logbl(long double x);
+long double logbl(long double x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/lrint.h b/libc/src/math/lrint.h
index 62df79a1de230..565cae847e3d4 100644
--- a/libc/src/math/lrint.h
+++ b/libc/src/math/lrint.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long lrint(double x);
+long lrint(double x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/lrintf.h b/libc/src/math/lrintf.h
index af5159437532b..604f53d76e5d3 100644
--- a/libc/src/math/lrintf.h
+++ b/libc/src/math/lrintf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long lrintf(float x);
+long lrintf(float x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/lrintl.h b/libc/src/math/lrintl.h
index 812acecadafad..e16070f7c220e 100644
--- a/libc/src/math/lrintl.h
+++ b/libc/src/math/lrintl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long lrintl(long double x);
+long lrintl(long double x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/lround.h b/libc/src/math/lround.h
index 8c555e816c8ba..78631d51562e3 100644
--- a/libc/src/math/lround.h
+++ b/libc/src/math/lround.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long lround(double x);
+long lround(double x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/lroundf.h b/libc/src/math/lroundf.h
index 3d318a7a2faba..19e31f1a156d1 100644
--- a/libc/src/math/lroundf.h
+++ b/libc/src/math/lroundf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long lroundf(float x);
+long lroundf(float x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/lroundl.h b/libc/src/math/lroundl.h
index a8b5aff0fcf38..b6116e80925ee 100644
--- a/libc/src/math/lroundl.h
+++ b/libc/src/math/lroundl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long lroundl(long double x);
+long lroundl(long double x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/modf.h b/libc/src/math/modf.h
index 1dc732f6e89ab..2816e1c53916f 100644
--- a/libc/src/math/modf.h
+++ b/libc/src/math/modf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double modf(double x, double *iptr);
+double modf(double x, double *iptr) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/modff.h b/libc/src/math/modff.h
index 21457e0d2e81a..36d5849836d54 100644
--- a/libc/src/math/modff.h
+++ b/libc/src/math/modff.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float modff(float x, float *iptr);
+float modff(float x, float *iptr) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/modfl.h b/libc/src/math/modfl.h
index ff89239c4bfde..44206211bdf2e 100644
--- a/libc/src/math/modfl.h
+++ b/libc/src/math/modfl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double modfl(long double x, long double *iptr);
+long double modfl(long double x, long double *iptr) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/nearbyint.h b/libc/src/math/nearbyint.h
index 957a06b979214..bde631c421549 100644
--- a/libc/src/math/nearbyint.h
+++ b/libc/src/math/nearbyint.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double nearbyint(double x);
+double nearbyint(double x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/nearbyintf.h b/libc/src/math/nearbyintf.h
index 3793f6bc1b881..9d1f42a905f1b 100644
--- a/libc/src/math/nearbyintf.h
+++ b/libc/src/math/nearbyintf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float nearbyintf(float x);
+float nearbyintf(float x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/nearbyintl.h b/libc/src/math/nearbyintl.h
index 7029e86a52114..8b896002e178b 100644
--- a/libc/src/math/nearbyintl.h
+++ b/libc/src/math/nearbyintl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double nearbyintl(long double x);
+long double nearbyintl(long double x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/nextafter.h b/libc/src/math/nextafter.h
index 1f6d24de5f2e0..89ff5cc4819b7 100644
--- a/libc/src/math/nextafter.h
+++ b/libc/src/math/nextafter.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double nextafter(double x, double y);
+double nextafter(double x, double y) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/nextafterf.h b/libc/src/math/nextafterf.h
index 8afac0e5f6a03..9ab90f26fa148 100644
--- a/libc/src/math/nextafterf.h
+++ b/libc/src/math/nextafterf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float nextafterf(float x, float y);
+float nextafterf(float x, float y) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/nextafterl.h b/libc/src/math/nextafterl.h
index 912877867dc21..14f652e9904b3 100644
--- a/libc/src/math/nextafterl.h
+++ b/libc/src/math/nextafterl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double nextafterl(long double x, long double y);
+long double nextafterl(long double x, long double y) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/remainder.h b/libc/src/math/remainder.h
index 8a720fc23b6be..924fc15ec6abb 100644
--- a/libc/src/math/remainder.h
+++ b/libc/src/math/remainder.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double remainder(double x, double y);
+double remainder(double x, double y) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/remainderf.h b/libc/src/math/remainderf.h
index 19a16d08a94d3..f177e5c7e08ea 100644
--- a/libc/src/math/remainderf.h
+++ b/libc/src/math/remainderf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float remainderf(float x, float y);
+float remainderf(float x, float y) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/remainderl.h b/libc/src/math/remainderl.h
index f2837635ab77c..2aeb09c2b56f8 100644
--- a/libc/src/math/remainderl.h
+++ b/libc/src/math/remainderl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double remainderl(long double x, long double y);
+long double remainderl(long double x, long double y) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/remquo.h b/libc/src/math/remquo.h
index cb753fee6ea0d..c4a0b686aca28 100644
--- a/libc/src/math/remquo.h
+++ b/libc/src/math/remquo.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double remquo(double x, double y, int *exp);
+double remquo(double x, double y, int *exp) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/remquof.h b/libc/src/math/remquof.h
index feb2e4f5e0dd5..53ae441acb475 100644
--- a/libc/src/math/remquof.h
+++ b/libc/src/math/remquof.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float remquof(float x, float y, int *exp);
+float remquof(float x, float y, int *exp) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/remquol.h b/libc/src/math/remquol.h
index d1b0e20fcc865..c50e3ec36faac 100644
--- a/libc/src/math/remquol.h
+++ b/libc/src/math/remquol.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double remquol(long double x, long double y, int *exp);
+long double remquol(long double x, long double y, int *exp) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/rint.h b/libc/src/math/rint.h
index e4910ad95a81c..f8b1a7612b527 100644
--- a/libc/src/math/rint.h
+++ b/libc/src/math/rint.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double rint(double x);
+double rint(double x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/rintf.h b/libc/src/math/rintf.h
index 0091ba3a8cd00..3de8f2703d4e7 100644
--- a/libc/src/math/rintf.h
+++ b/libc/src/math/rintf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float rintf(float x);
+float rintf(float x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/rintl.h b/libc/src/math/rintl.h
index 2bf095de76f88..93d45b394ab5f 100644
--- a/libc/src/math/rintl.h
+++ b/libc/src/math/rintl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double rintl(long double x);
+long double rintl(long double x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/round.h b/libc/src/math/round.h
index bb09ea4a77c53..b0378a577e2f2 100644
--- a/libc/src/math/round.h
+++ b/libc/src/math/round.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double round(double x);
+double round(double x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/roundf.h b/libc/src/math/roundf.h
index 6bab35adf781a..8d39f4267ed61 100644
--- a/libc/src/math/roundf.h
+++ b/libc/src/math/roundf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float roundf(float x);
+float roundf(float x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/roundl.h b/libc/src/math/roundl.h
index 43fb63e231de4..0b3aced3b2fa5 100644
--- a/libc/src/math/roundl.h
+++ b/libc/src/math/roundl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double roundl(long double x);
+long double roundl(long double x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/sin.h b/libc/src/math/sin.h
index f3919c46df603..43dbe80fdb91c 100644
--- a/libc/src/math/sin.h
+++ b/libc/src/math/sin.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double sin(double x);
+double sin(double x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/sincosf.h b/libc/src/math/sincosf.h
index 47ef983f4385f..430f6f6417ae4 100644
--- a/libc/src/math/sincosf.h
+++ b/libc/src/math/sincosf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-void sincosf(float x, float *sinx, float *cosx);
+void sincosf(float x, float *sinx, float *cosx) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/sinf.h b/libc/src/math/sinf.h
index e63db04c51b5d..8e6b4f3dc0c30 100644
--- a/libc/src/math/sinf.h
+++ b/libc/src/math/sinf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float sinf(float x);
+float sinf(float x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/sqrt.h b/libc/src/math/sqrt.h
index 2390e07b5dce5..26dc527e8a5c0 100644
--- a/libc/src/math/sqrt.h
+++ b/libc/src/math/sqrt.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double sqrt(double x);
+double sqrt(double x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/sqrtf.h b/libc/src/math/sqrtf.h
index d1d06f3adfa8e..6ab9dbe208d7d 100644
--- a/libc/src/math/sqrtf.h
+++ b/libc/src/math/sqrtf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float sqrtf(float x);
+float sqrtf(float x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/sqrtl.h b/libc/src/math/sqrtl.h
index 5fbfa14507147..a033849d77c85 100644
--- a/libc/src/math/sqrtl.h
+++ b/libc/src/math/sqrtl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double sqrtl(long double x);
+long double sqrtl(long double x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/tan.h b/libc/src/math/tan.h
index 05366db52ff87..6e733be6746ff 100644
--- a/libc/src/math/tan.h
+++ b/libc/src/math/tan.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double tan(double x);
+double tan(double x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/trunc.h b/libc/src/math/trunc.h
index f7fed01f30d25..dba5d37d027f8 100644
--- a/libc/src/math/trunc.h
+++ b/libc/src/math/trunc.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double trunc(double x);
+double trunc(double x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/truncf.h b/libc/src/math/truncf.h
index b4f1cd7ea72f6..83f93b9dbf354 100644
--- a/libc/src/math/truncf.h
+++ b/libc/src/math/truncf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float truncf(float x);
+float truncf(float x) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/truncl.h b/libc/src/math/truncl.h
index 2a78ffaa3c5ef..4b005c1e696ad 100644
--- a/libc/src/math/truncl.h
+++ b/libc/src/math/truncl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double truncl(long double x);
+long double truncl(long double x) noexcept;
 
 } // namespace __llvm_libc
 

From 857d6ccbc48c5b549b828c7cd15c963517acd188 Mon Sep 17 00:00:00 2001
From: Alfonso Gregory <83477269+gAlfonso-bit@users.noreply.github.com>
Date: Mon, 26 Jul 2021 12:01:22 -0400
Subject: [PATCH 06/17] stdlib and signal

---
 libc/config/linux/x86_64/syscall.h.inc | 159 +++++++++++++------------
 libc/src/signal/linux/sigaction.cpp    |   2 +-
 libc/src/signal/linux/sigaddset.cpp    |   4 +-
 libc/src/signal/linux/sigdelset.cpp    |   4 +-
 libc/src/signal/linux/sigemptyset.cpp  |   2 +-
 libc/src/signal/linux/sigfillset.cpp   |   2 +-
 libc/src/signal/linux/signal.h         |   4 +-
 libc/src/signal/raise.h                |   2 +-
 libc/src/signal/sigaction.h            |   2 +-
 libc/src/signal/sigaddset.h            |   2 +-
 libc/src/signal/sigdelset.h            |   2 +-
 libc/src/signal/sigemptyset.h          |   2 +-
 libc/src/signal/sigfillset.h           |   2 +-
 libc/src/signal/signal.h               |   2 +-
 libc/src/signal/sigprocmask.h          |   2 +-
 libc/src/stdio/FILE.h                  |   2 +-
 libc/src/stdio/fwrite.cpp              |   4 +-
 libc/src/stdio/fwrite.h                |   2 +-
 libc/src/stdlib/abort.cpp              |   2 +-
 libc/src/stdlib/abs.h                  |   2 +-
 libc/src/stdlib/labs.h                 |   2 +-
 libc/src/stdlib/linux/_Exit.cpp        |   2 +-
 libc/src/stdlib/llabs.h                |   2 +-
 23 files changed, 106 insertions(+), 105 deletions(-)

diff --git a/libc/config/linux/x86_64/syscall.h.inc b/libc/config/linux/x86_64/syscall.h.inc
index ee3b5e5bfc0d7..de34d8ed21625 100644
--- a/libc/config/linux/x86_64/syscall.h.inc
+++ b/libc/config/linux/x86_64/syscall.h.inc
@@ -14,92 +14,93 @@
 
 namespace __llvm_libc {
 
-__attribute__((always_inline)) inline long syscall(long __number) {
-  long retcode;
-  LIBC_INLINE_ASM("syscall"
-                  : "=a"(retcode)
-                  : "a"(__number)
-                  : SYSCALL_CLOBBER_LIST);
-  return retcode;
-}
+  __attribute__((always_inline)) inline long syscall(long __number) noexcept {
+    long retcode;
+    LIBC_INLINE_ASM("syscall"
+                    : "=a"(retcode)
+                    : "a"(__number)
+                    : SYSCALL_CLOBBER_LIST);
+    return retcode;
+  }
 
-__attribute__((always_inline)) inline long syscall(long __number, long __arg1) {
-  long retcode;
-  LIBC_INLINE_ASM("syscall"
-                  : "=a"(retcode)
-                  : "a"(__number), "D"(__arg1)
-                  : SYSCALL_CLOBBER_LIST);
-  return retcode;
-}
+  __attribute__((always_inline)) inline long syscall(long __number,
+                                                     long __arg1) noexcept {
+    long retcode;
+    LIBC_INLINE_ASM("syscall"
+                    : "=a"(retcode)
+                    : "a"(__number), "D"(__arg1)
+                    : SYSCALL_CLOBBER_LIST);
+    return retcode;
+  }
 
-__attribute__((always_inline)) inline long syscall(long __number, long __arg1,
-                                                   long __arg2) {
-  long retcode;
-  LIBC_INLINE_ASM("syscall"
-                  : "=a"(retcode)
-                  : "a"(__number), "D"(__arg1), "S"(__arg2)
-                  : SYSCALL_CLOBBER_LIST);
-  return retcode;
-}
+  __attribute__((always_inline)) inline long syscall(long __number, long __arg1,
+                                                     long __arg2) noexcept {
+    long retcode;
+    LIBC_INLINE_ASM("syscall"
+                    : "=a"(retcode)
+                    : "a"(__number), "D"(__arg1), "S"(__arg2)
+                    : SYSCALL_CLOBBER_LIST);
+    return retcode;
+  }
 
-__attribute__((always_inline)) inline long syscall(long __number, long __arg1,
-                                                   long __arg2, long __arg3) {
-  long retcode;
-  LIBC_INLINE_ASM("syscall"
-                  : "=a"(retcode)
-                  : "a"(__number), "D"(__arg1), "S"(__arg2), "d"(__arg3)
-                  : SYSCALL_CLOBBER_LIST);
-  return retcode;
-}
+  __attribute__((always_inline)) inline long syscall(
+      long __number, long __arg1, long __arg2, long __arg3) noexcept {
+    long retcode;
+    LIBC_INLINE_ASM("syscall"
+                    : "=a"(retcode)
+                    : "a"(__number), "D"(__arg1), "S"(__arg2), "d"(__arg3)
+                    : SYSCALL_CLOBBER_LIST);
+    return retcode;
+  }
 
-__attribute__((always_inline)) inline long
-syscall(long __number, long __arg1, long __arg2, long __arg3, long __arg4) {
-  long retcode;
-  register long r10 __asm__("r10") = __arg4;
-  LIBC_INLINE_ASM("syscall"
-                  : "=a"(retcode)
-                  : "a"(__number), "D"(__arg1), "S"(__arg2), "d"(__arg3),
-                    "r"(r10)
-                  : SYSCALL_CLOBBER_LIST);
-  return retcode;
-}
+  __attribute__((always_inline)) inline long syscall(long __number, long __arg1,
+                                                     long __arg2, long __arg3,
+                                                     long __arg4) noexcept {
+    long retcode;
+    register long r10 __asm__("r10") = __arg4;
+    LIBC_INLINE_ASM("syscall"
+                    : "=a"(retcode)
+                    : "a"(__number), "D"(__arg1), "S"(__arg2), "d"(__arg3),
+                      "r"(r10)
+                    : SYSCALL_CLOBBER_LIST);
+    return retcode;
+  }
 
-__attribute__((always_inline)) inline long syscall(long __number, long __arg1,
-                                                   long __arg2, long __arg3,
-                                                   long __arg4, long __arg5) {
-  long retcode;
-  register long r10 __asm__("r10") = __arg4;
-  register long r8 __asm__("r8") = __arg5;
-  LIBC_INLINE_ASM("syscall"
-                  : "=a"(retcode)
-                  : "a"(__number), "D"(__arg1), "S"(__arg2), "d"(__arg3),
-                    "r"(r10), "r"(r8)
-                  : SYSCALL_CLOBBER_LIST);
-  return retcode;
-}
+  __attribute__((always_inline)) inline long syscall(
+      long __number, long __arg1, long __arg2, long __arg3, long __arg4,
+      long __arg5) noexcept {
+    long retcode;
+    register long r10 __asm__("r10") = __arg4;
+    register long r8 __asm__("r8") = __arg5;
+    LIBC_INLINE_ASM("syscall"
+                    : "=a"(retcode)
+                    : "a"(__number), "D"(__arg1), "S"(__arg2), "d"(__arg3),
+                      "r"(r10), "r"(r8)
+                    : SYSCALL_CLOBBER_LIST);
+    return retcode;
+  }
 
-__attribute__((always_inline)) inline long syscall(long __number, long __arg1,
-                                                   long __arg2, long __arg3,
-                                                   long __arg4, long __arg5,
-                                                   long __arg6) {
-  long retcode;
-  register long r10 __asm__("r10") = __arg4;
-  register long r8 __asm__("r8") = __arg5;
-  register long r9 __asm__("r9") = __arg6;
-  LIBC_INLINE_ASM("syscall"
-                  : "=a"(retcode)
-                  : "a"(__number), "D"(__arg1), "S"(__arg2), "d"(__arg3),
-                    "r"(r10), "r"(r8), "r"(r9)
-                  : SYSCALL_CLOBBER_LIST);
-  return retcode;
-}
-
-template <typename... Ts>
-__attribute__((always_inline)) inline long syscall(long __number, Ts... ts) {
-  static_assert(sizeof...(Ts) <= 6, "Too many arguments for syscall");
-  return syscall(__number, (long)ts...);
-}
+  __attribute__((always_inline)) inline long syscall(
+      long __number, long __arg1, long __arg2, long __arg3, long __arg4,
+      long __arg5, long __arg6) noexcept {
+    long retcode;
+    register long r10 __asm__("r10") = __arg4;
+    register long r8 __asm__("r8") = __arg5;
+    register long r9 __asm__("r9") = __arg6;
+    LIBC_INLINE_ASM("syscall"
+                    : "=a"(retcode)
+                    : "a"(__number), "D"(__arg1), "S"(__arg2), "d"(__arg3),
+                      "r"(r10), "r"(r8), "r"(r9)
+                    : SYSCALL_CLOBBER_LIST);
+    return retcode;
+  }
 
+  template <typename... Ts>
+  __attribute__((always_inline)) inline long syscall(long __number,
+                                                     Ts... ts) noexcept {
+    static_assert(sizeof...(Ts) <= 6, "Too many arguments for syscall");
+    return syscall(__number, static_cast<long>(ts...));
+  }
 
 #undef SYSCALL_CLOBBER_LIST
 
diff --git a/libc/src/signal/linux/sigaction.cpp b/libc/src/signal/linux/sigaction.cpp
index 602fc71bf390c..8ecda77d6f8d3 100644
--- a/libc/src/signal/linux/sigaction.cpp
+++ b/libc/src/signal/linux/sigaction.cpp
@@ -21,7 +21,7 @@ namespace __llvm_libc {
 extern "C" void __restore_rt();
 
 template <typename T, typename V>
-static void copySigaction(T &dest, const V &source) {
+static void copySigaction(T &dest, const V &source) noexcept {
   dest.sa_handler = source.sa_handler;
   dest.sa_mask = source.sa_mask;
   dest.sa_flags = source.sa_flags;
diff --git a/libc/src/signal/linux/sigaddset.cpp b/libc/src/signal/linux/sigaddset.cpp
index bc51ef67e0b3a..a7732645dea9a 100644
--- a/libc/src/signal/linux/sigaddset.cpp
+++ b/libc/src/signal/linux/sigaddset.cpp
@@ -15,8 +15,8 @@
 
 namespace __llvm_libc {
 
-LLVM_LIBC_FUNCTION(int, sigaddset, (sigset_t * set, int signum)) {
-  if (!set || (unsigned)(signum - 1) >= (8 * sizeof(sigset_t))) {
+LLVM_LIBC_FUNCTION(int, sigaddset, (sigset_t * set, int signum)) noexcept {
+  if (!set || static_cast<unsigned>(signum - 1) >= (8 * sizeof(sigset_t))) {
     llvmlibc_errno = EINVAL;
     return -1;
   }
diff --git a/libc/src/signal/linux/sigdelset.cpp b/libc/src/signal/linux/sigdelset.cpp
index f870f71560074..60b84a3f9865f 100644
--- a/libc/src/signal/linux/sigdelset.cpp
+++ b/libc/src/signal/linux/sigdelset.cpp
@@ -15,8 +15,8 @@
 
 namespace __llvm_libc {
 
-LLVM_LIBC_FUNCTION(int, sigdelset, (sigset_t * set, int signum)) {
-  if (!set || (unsigned)(signum - 1) >= (8 * sizeof(sigset_t))) {
+LLVM_LIBC_FUNCTION(int, sigdelset, (sigset_t * set, int signum)) noexcept {
+  if (!set || static_cast<unsigned>(signum - 1) >= (8 * sizeof(sigset_t))) {
     llvmlibc_errno = EINVAL;
     return -1;
   }
diff --git a/libc/src/signal/linux/sigemptyset.cpp b/libc/src/signal/linux/sigemptyset.cpp
index bce5fea7c963b..542e2f8635b3f 100644
--- a/libc/src/signal/linux/sigemptyset.cpp
+++ b/libc/src/signal/linux/sigemptyset.cpp
@@ -15,7 +15,7 @@
 
 namespace __llvm_libc {
 
-LLVM_LIBC_FUNCTION(int, sigemptyset, (sigset_t * set)) {
+LLVM_LIBC_FUNCTION(int, sigemptyset, (sigset_t * set)) noexcept {
   if (!set) {
     llvmlibc_errno = EINVAL;
     return -1;
diff --git a/libc/src/signal/linux/sigfillset.cpp b/libc/src/signal/linux/sigfillset.cpp
index 1b908f1992640..1377263c7b17b 100644
--- a/libc/src/signal/linux/sigfillset.cpp
+++ b/libc/src/signal/linux/sigfillset.cpp
@@ -15,7 +15,7 @@
 
 namespace __llvm_libc {
 
-LLVM_LIBC_FUNCTION(int, sigfillset, (sigset_t * set)) {
+LLVM_LIBC_FUNCTION(int, sigfillset, (sigset_t * set)) noexcept {
   if (!set) {
     llvmlibc_errno = EINVAL;
     return -1;
diff --git a/libc/src/signal/linux/signal.h b/libc/src/signal/linux/signal.h
index 89b471b4079e4..d9687952713bd 100644
--- a/libc/src/signal/linux/signal.h
+++ b/libc/src/signal/linux/signal.h
@@ -35,7 +35,7 @@ struct Sigset {
 
 constexpr static Sigset all = Sigset::fullset();
 
-static inline int block_all_signals(Sigset &set) {
+static inline int block_all_signals(Sigset &set) noexcept {
   sigset_t nativeSigset = all;
   sigset_t oldSet = set;
   int ret = __llvm_libc::syscall(SYS_rt_sigprocmask, SIG_BLOCK, &nativeSigset,
@@ -44,7 +44,7 @@ static inline int block_all_signals(Sigset &set) {
   return ret;
 }
 
-static inline int restore_signals(const Sigset &set) {
+static inline int restore_signals(const Sigset &set) noexcept {
   sigset_t nativeSigset = set;
   return __llvm_libc::syscall(SYS_rt_sigprocmask, SIG_SETMASK, &nativeSigset,
                               nullptr, sizeof(sigset_t));
diff --git a/libc/src/signal/raise.h b/libc/src/signal/raise.h
index 00fd4c8fbda99..d477fca998090 100644
--- a/libc/src/signal/raise.h
+++ b/libc/src/signal/raise.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-int raise(int sig);
+int raise(int sig) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/signal/sigaction.h b/libc/src/signal/sigaction.h
index 105ab1b250cc6..c72902cd79946 100644
--- a/libc/src/signal/sigaction.h
+++ b/libc/src/signal/sigaction.h
@@ -15,7 +15,7 @@
 namespace __llvm_libc {
 
 int sigaction(int signal, const struct __sigaction *__restrict libc_new,
-              struct __sigaction *__restrict libc_old);
+              struct __sigaction *__restrict libc_old) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/signal/sigaddset.h b/libc/src/signal/sigaddset.h
index 40cec9f00c647..7eb76ccc92439 100644
--- a/libc/src/signal/sigaddset.h
+++ b/libc/src/signal/sigaddset.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-int sigaddset(sigset_t *set, int signum);
+int sigaddset(sigset_t *set, int signum) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/signal/sigdelset.h b/libc/src/signal/sigdelset.h
index a005d9c0aa138..c055d34010f35 100644
--- a/libc/src/signal/sigdelset.h
+++ b/libc/src/signal/sigdelset.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-int sigdelset(sigset_t *set, int signum);
+int sigdelset(sigset_t *set, int signum) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/signal/sigemptyset.h b/libc/src/signal/sigemptyset.h
index 0651c7302f992..7d418a06ade7e 100644
--- a/libc/src/signal/sigemptyset.h
+++ b/libc/src/signal/sigemptyset.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-int sigemptyset(sigset_t *set);
+int sigemptyset(sigset_t *set) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/signal/sigfillset.h b/libc/src/signal/sigfillset.h
index ed3612ce4ed5a..af60fb86694eb 100644
--- a/libc/src/signal/sigfillset.h
+++ b/libc/src/signal/sigfillset.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-int sigfillset(sigset_t *set);
+int sigfillset(sigset_t *set) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/signal/signal.h b/libc/src/signal/signal.h
index 4315497e2cf8c..bd10c6d61de4f 100644
--- a/libc/src/signal/signal.h
+++ b/libc/src/signal/signal.h
@@ -15,7 +15,7 @@ namespace __llvm_libc {
 
 using sighandler_t = __sighandler_t;
 
-sighandler_t signal(int signum, sighandler_t handler);
+sighandler_t signal(int signum, sighandler_t handler) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/signal/sigprocmask.h b/libc/src/signal/sigprocmask.h
index 353c0c84b38a1..41a79f6a5706c 100644
--- a/libc/src/signal/sigprocmask.h
+++ b/libc/src/signal/sigprocmask.h
@@ -14,7 +14,7 @@
 namespace __llvm_libc {
 
 int sigprocmask(int how, const sigset_t *__restrict set,
-                sigset_t *__restrict oldset);
+                sigset_t *__restrict oldset) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/stdio/FILE.h b/libc/src/stdio/FILE.h
index 54bc9b2c87311..7051838af4945 100644
--- a/libc/src/stdio/FILE.h
+++ b/libc/src/stdio/FILE.h
@@ -19,7 +19,7 @@ struct FILE {
 
   using write_function_t = size_t(FILE *, const char *, size_t);
 
-  write_function_t *write;
+  write_function_t *write noexcept;
 };
 
 } // namespace __llvm_libc
diff --git a/libc/src/stdio/fwrite.cpp b/libc/src/stdio/fwrite.cpp
index 80cf50ca376e4..d54aad2ec0934 100644
--- a/libc/src/stdio/fwrite.cpp
+++ b/libc/src/stdio/fwrite.cpp
@@ -14,13 +14,13 @@
 namespace __llvm_libc {
 
 size_t fwrite_unlocked(const void *__restrict ptr, size_t size, size_t nmeb,
-                       __llvm_libc::FILE *__restrict stream) {
+                       __llvm_libc::FILE *__restrict stream) noexcept {
   return stream->write(stream, reinterpret_cast<const char *>(ptr),
                        size * nmeb);
 }
 
 size_t fwrite(const void *__restrict ptr, size_t size, size_t nmeb,
-              __llvm_libc::FILE *__restrict stream) {
+              __llvm_libc::FILE *__restrict stream) noexcept {
   __llvm_libc::mtx_lock(&stream->lock);
   size_t written = fwrite_unlocked(ptr, size, nmeb, stream);
   __llvm_libc::mtx_unlock(&stream->lock);
diff --git a/libc/src/stdio/fwrite.h b/libc/src/stdio/fwrite.h
index 8a71ca105bb08..7dd03da033434 100644
--- a/libc/src/stdio/fwrite.h
+++ b/libc/src/stdio/fwrite.h
@@ -15,7 +15,7 @@
 namespace __llvm_libc {
 
 size_t fwrite(const void *__restrict ptr, size_t size, size_t nmeb,
-              __llvm_libc::FILE *__restrict stream);
+              __llvm_libc::FILE *__restrict stream) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/stdlib/abort.cpp b/libc/src/stdlib/abort.cpp
index 1da81611273de..0dfab6ebbeded 100644
--- a/libc/src/stdlib/abort.cpp
+++ b/libc/src/stdlib/abort.cpp
@@ -14,7 +14,7 @@
 
 namespace __llvm_libc {
 
-LLVM_LIBC_FUNCTION(void, abort, ()) {
+[[noreturn]] LLVM_LIBC_FUNCTION(void, abort, ()) {
   // TODO: When sigprocmask and sigaction land:
   // Unblock SIGABRT, raise it, if it was ignored or the handler returned,
   // change its action to SIG_DFL, raise it again.
diff --git a/libc/src/stdlib/abs.h b/libc/src/stdlib/abs.h
index 42ef7f885ed65..d7fc1fd91f522 100644
--- a/libc/src/stdlib/abs.h
+++ b/libc/src/stdlib/abs.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int abs(int n);
+int abs(int n) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/stdlib/labs.h b/libc/src/stdlib/labs.h
index 0f0ea99dc22a7..5d52ca9701de6 100644
--- a/libc/src/stdlib/labs.h
+++ b/libc/src/stdlib/labs.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long labs(long n);
+long labs(long n) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/stdlib/linux/_Exit.cpp b/libc/src/stdlib/linux/_Exit.cpp
index 7fdd60ffe9bc6..89b223b35a6ba 100644
--- a/libc/src/stdlib/linux/_Exit.cpp
+++ b/libc/src/stdlib/linux/_Exit.cpp
@@ -14,7 +14,7 @@
 
 namespace __llvm_libc {
 
-LLVM_LIBC_FUNCTION(void, _Exit, (int status)) {
+[[noreturn]] LLVM_LIBC_FUNCTION(void, _Exit, (int status)) {
   for (;;) {
     __llvm_libc::syscall(SYS_exit_group, status);
     __llvm_libc::syscall(SYS_exit, status);
diff --git a/libc/src/stdlib/llabs.h b/libc/src/stdlib/llabs.h
index f173431a14f15..fcbe64ca45682 100644
--- a/libc/src/stdlib/llabs.h
+++ b/libc/src/stdlib/llabs.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long long llabs(long long n);
+long long llabs(long long n) noexcept;
 
 } // namespace __llvm_libc
 

From 690324b85eb3af5f5c114433b6a69a54e2fa7523 Mon Sep 17 00:00:00 2001
From: Alfonso Gregory <83477269+gAlfonso-bit@users.noreply.github.com>
Date: Mon, 26 Jul 2021 12:47:41 -0400
Subject: [PATCH 07/17] Done

---
 libc/src/sys/mman/mmap.h                      |  3 +-
 libc/src/sys/mman/munmap.h                    |  2 +-
 libc/src/threads/call_once.h                  |  2 +-
 libc/src/threads/linux/thrd_create.cpp        |  2 +-
 .../linux/x86_64/thread_start_args.h.in       |  2 +-
 libc/src/threads/mtx_init.h                   |  2 +-
 libc/src/threads/mtx_lock.h                   |  2 +-
 libc/src/threads/mtx_unlock.h                 |  2 +-
 libc/src/threads/thrd_create.h                |  2 +-
 libc/src/threads/thrd_join.h                  |  2 +-
 libc/src/time/asctime.h                       |  2 +-
 libc/src/time/asctime_r.h                     |  2 +-
 libc/src/time/gmtime.h                        |  2 +-
 libc/src/time/gmtime_r.h                      |  2 +-
 libc/src/time/mktime.h                        |  2 +-
 libc/src/time/time_utils.h                    |  8 +--
 libc/src/unistd/write.h                       |  2 +-
 libc/utils/CPP/Array.h                        |  2 +-
 libc/utils/CPP/ArrayRef.h                     | 26 +++++----
 libc/utils/FPUtil/BasicOperations.h           |  6 +-
 .../FPUtil/DivisionAndRemainderOperations.h   |  2 +-
 libc/utils/FPUtil/FPBits.h                    | 40 +++++++------
 libc/utils/FPUtil/Hypot.h                     |  8 +--
 libc/utils/FPUtil/LongDoubleBitsX86.h         | 40 +++++++------
 libc/utils/FPUtil/ManipulationFunctions.h     | 14 ++---
 libc/utils/FPUtil/NearestIntegerOperations.h  | 16 +++---
 libc/utils/FPUtil/NextAfterLongDoubleX86.h    |  2 +-
 libc/utils/FPUtil/NormalFloat.h               | 12 ++--
 libc/utils/FPUtil/PolyEval.h                  | 12 ++--
 libc/utils/FPUtil/Sqrt.h                      | 15 +++--
 libc/utils/FPUtil/SqrtLongDoubleX86.h         |  5 +-
 llvm/include/llvm/Support/Compiler.h          |  4 +-
 llvm/lib/TableGen/Error.cpp                   | 57 +++++++++++--------
 33 files changed, 166 insertions(+), 136 deletions(-)

diff --git a/libc/src/sys/mman/mmap.h b/libc/src/sys/mman/mmap.h
index c7aa404f65857..1cae4a7983d9d 100644
--- a/libc/src/sys/mman/mmap.h
+++ b/libc/src/sys/mman/mmap.h
@@ -13,7 +13,8 @@
 
 namespace __llvm_libc {
 
-void *mmap(void *addr, size_t size, int prot, int flags, int fd, off_t offset);
+void *mmap(void *addr, size_t size, int prot, int flags, int fd,
+           off_t offset) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/sys/mman/munmap.h b/libc/src/sys/mman/munmap.h
index ba272dc45e15f..72cd7508be9d0 100644
--- a/libc/src/sys/mman/munmap.h
+++ b/libc/src/sys/mman/munmap.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-int munmap(void *addr, size_t size);
+int munmap(void *addr, size_t size) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/threads/call_once.h b/libc/src/threads/call_once.h
index f6602df68197c..a4a8363594097 100644
--- a/libc/src/threads/call_once.h
+++ b/libc/src/threads/call_once.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-void call_once(once_flag *flag, __call_once_func_t func);
+void call_once(once_flag *flag, __call_once_func_t func) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/threads/linux/thrd_create.cpp b/libc/src/threads/linux/thrd_create.cpp
index 8b68f2a48688d..449b4a4f25f98 100644
--- a/libc/src/threads/linux/thrd_create.cpp
+++ b/libc/src/threads/linux/thrd_create.cpp
@@ -30,7 +30,7 @@ struct StartArgs {
   void *arg;
 };
 
-static __attribute__((noinline)) void start_thread() {
+static __attribute__((noinline)) void start_thread() noexcept {
   StartArgs *start_args = reinterpret_cast<StartArgs *>(get_start_args_addr());
   __llvm_libc::syscall(SYS_exit, start_args->thread->__retval =
                                      start_args->func(start_args->arg));
diff --git a/libc/src/threads/linux/x86_64/thread_start_args.h.in b/libc/src/threads/linux/x86_64/thread_start_args.h.in
index 36365b98bb214..43e04ce4d34d5 100644
--- a/libc/src/threads/linux/x86_64/thread_start_args.h.in
+++ b/libc/src/threads/linux/x86_64/thread_start_args.h.in
@@ -10,7 +10,7 @@
 
 namespace __llvm_libc {
 
-__attribute__((always_inline)) inline uintptr_t get_start_args_addr() {
+__attribute__((always_inline)) inline uintptr_t get_start_args_addr() noexcept {
   // NOTE: For __builtin_frame_address to work reliably across compilers,
   // architectures and various optimization levels, the TU including this file
   // should be compiled with -fno-omit-frame-pointer.
diff --git a/libc/src/threads/mtx_init.h b/libc/src/threads/mtx_init.h
index 7eed5ece6d5e7..a7302746a8ef5 100644
--- a/libc/src/threads/mtx_init.h
+++ b/libc/src/threads/mtx_init.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-int mtx_init(mtx_t *mutex, int type);
+int mtx_init(mtx_t *mutex, int type) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/threads/mtx_lock.h b/libc/src/threads/mtx_lock.h
index 5086f773f0fe6..6afd9d6da5ad4 100644
--- a/libc/src/threads/mtx_lock.h
+++ b/libc/src/threads/mtx_lock.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-int mtx_lock(mtx_t *mutex);
+int mtx_lock(mtx_t *mutex) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/threads/mtx_unlock.h b/libc/src/threads/mtx_unlock.h
index 55f0b4a7a6655..a28679993b495 100644
--- a/libc/src/threads/mtx_unlock.h
+++ b/libc/src/threads/mtx_unlock.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-int mtx_unlock(mtx_t *mutex);
+int mtx_unlock(mtx_t *mutex) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/threads/thrd_create.h b/libc/src/threads/thrd_create.h
index d2bb7dfad41c5..859d2cbec7eb0 100644
--- a/libc/src/threads/thrd_create.h
+++ b/libc/src/threads/thrd_create.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-int thrd_create(thrd_t *thread, thrd_start_t func, void *arg);
+int thrd_create(thrd_t *thread, thrd_start_t func, void *arg) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/threads/thrd_join.h b/libc/src/threads/thrd_join.h
index fc36503dc521c..fa9f6ebc0a806 100644
--- a/libc/src/threads/thrd_join.h
+++ b/libc/src/threads/thrd_join.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-int thrd_join(thrd_t *thread, int *retval);
+int thrd_join(thrd_t *thread, int *retval) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/time/asctime.h b/libc/src/time/asctime.h
index 9d75b40148afd..c0c6bfa258794 100644
--- a/libc/src/time/asctime.h
+++ b/libc/src/time/asctime.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-char *asctime(const struct tm *timeptr);
+char *asctime(const struct tm *timeptr) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/time/asctime_r.h b/libc/src/time/asctime_r.h
index 8521e782a509d..56c75826bf4bc 100644
--- a/libc/src/time/asctime_r.h
+++ b/libc/src/time/asctime_r.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-char *asctime_r(const struct tm *timeptr, char *buffer);
+char *asctime_r(const struct tm *timeptr, char *buffer) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/time/gmtime.h b/libc/src/time/gmtime.h
index 8891a8c917ac5..7203c743fc02b 100644
--- a/libc/src/time/gmtime.h
+++ b/libc/src/time/gmtime.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-struct tm *gmtime(const time_t *timer);
+struct tm *gmtime(const time_t *timer) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/time/gmtime_r.h b/libc/src/time/gmtime_r.h
index 8e9fc94b5ceed..9476b6d82353d 100644
--- a/libc/src/time/gmtime_r.h
+++ b/libc/src/time/gmtime_r.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-struct tm *gmtime_r(const time_t *timer, struct tm *result);
+struct tm *gmtime_r(const time_t *timer, struct tm *result) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/time/mktime.h b/libc/src/time/mktime.h
index ecd604c12fc35..b153cd24937a6 100644
--- a/libc/src/time/mktime.h
+++ b/libc/src/time/mktime.h
@@ -14,7 +14,7 @@
 
 namespace __llvm_libc {
 
-time_t mktime(struct tm *t1);
+time_t mktime(struct tm *t1) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/time/time_utils.h b/libc/src/time/time_utils.h
index c1c7735f49060..327a6538a170c 100644
--- a/libc/src/time/time_utils.h
+++ b/libc/src/time/time_utils.h
@@ -68,15 +68,15 @@ struct TimeConstants {
 extern int64_t UpdateFromSeconds(int64_t total_seconds, struct tm *tm);
 
 // POSIX.1-2017 requires this.
-static inline time_t OutOfRange() {
+static inline time_t OutOfRange() noexcept {
   llvmlibc_errno = EOVERFLOW;
   return static_cast<time_t>(-1);
 }
 
-static inline void InvalidValue() { llvmlibc_errno = EINVAL; }
+static inline void InvalidValue() noexcept { llvmlibc_errno = EINVAL; }
 
 static inline char *asctime(const struct tm *timeptr, char *buffer,
-                            size_t bufferLength) {
+                            size_t bufferLength) noexcept {
   if (timeptr == nullptr || buffer == nullptr) {
     InvalidValue();
     return nullptr;
@@ -114,7 +114,7 @@ static inline char *asctime(const struct tm *timeptr, char *buffer,
 }
 
 static inline struct tm *gmtime_internal(const time_t *timer,
-                                         struct tm *result) {
+                                         struct tm *result) noexcept {
   int64_t seconds = *timer;
   // Update the tm structure's year, month, day, etc. from seconds.
   if (UpdateFromSeconds(seconds, result) < 0) {
diff --git a/libc/src/unistd/write.h b/libc/src/unistd/write.h
index d69c10a66f0f1..0ad6981645604 100644
--- a/libc/src/unistd/write.h
+++ b/libc/src/unistd/write.h
@@ -14,7 +14,7 @@
 
 namespace __llvm_libc {
 
-ssize_t write(int fd, const void *buf, size_t count);
+ssize_t write(int fd, const void *buf, size_t count) noexcept;
 
 } // namespace __llvm_libc
 
diff --git a/libc/utils/CPP/Array.h b/libc/utils/CPP/Array.h
index c774a9f793d8c..9085ebd66f054 100644
--- a/libc/utils/CPP/Array.h
+++ b/libc/utils/CPP/Array.h
@@ -43,7 +43,7 @@ template <class T, size_t N> struct Array {
   constexpr const_iterator begin() const { return Data; }
 
   constexpr iterator end() { return Data + N; }
-  const_iterator end() const { return Data + N; }
+  const_iterator end() const noexcept { return Data + N; }
 };
 
 } // namespace cpp
diff --git a/libc/utils/CPP/ArrayRef.h b/libc/utils/CPP/ArrayRef.h
index cad7db9d3b663..9df6b7d7e2c4e 100644
--- a/libc/utils/CPP/ArrayRef.h
+++ b/libc/utils/CPP/ArrayRef.h
@@ -50,44 +50,46 @@ template <typename QualifiedT> class ArrayRefBase {
   template <size_t N>
   constexpr ArrayRefBase(QualifiedT (&Arr)[N]) : Data(Arr), Length(N) {}
 
-  QualifiedT *data() const { return Data; }
-  size_t size() const { return Length; }
+  QualifiedT *data() const noexcept { return Data; }
+  size_t size() const noexcept { return Length; }
 
-  auto begin() const { return data(); }
-  auto end() const { return data() + size(); }
+  auto begin() const noexcept { return data(); }
+  auto end() const noexcept { return data() + size(); }
 
-  bool empty() const { return size() == 0; }
+  bool empty() const noexcept { return size() == 0; }
 
   auto operator[](size_t Index) const { return data()[Index]; }
 
   // slice(n, m) - Chop off the first N elements of the array, and keep M
   // elements in the array.
-  auto slice(size_t N, size_t M) const { return ArrayRefBase(data() + N, M); }
+  auto slice(size_t N, size_t M) const noexcept {
+    return ArrayRefBase(data() + N, M);
+  }
   // slice(n) - Chop off the first N elements of the array.
-  auto slice(size_t N) const { return slice(N, size() - N); }
+  auto slice(size_t N) const noexcept { return slice(N, size() - N); }
 
   // Drop the first \p N elements of the array.
-  auto drop_front(size_t N = 1) const { return slice(N, size() - N); }
+  auto drop_front(size_t N = 1) const noexcept { return slice(N, size() - N); }
 
   // Drop the last \p N elements of the array.
-  auto drop_back(size_t N = 1) const { return slice(0, size() - N); }
+  auto drop_back(size_t N = 1) const noexcept { return slice(0, size() - N); }
 
   // Return a copy of *this with only the first \p N elements.
-  auto take_front(size_t N = 1) const {
+  auto take_front(size_t N = 1) const noexcept {
     if (N >= size())
       return *this;
     return drop_back(size() - N);
   }
 
   // Return a copy of *this with only the last \p N elements.
-  auto take_back(size_t N = 1) const {
+  auto take_back(size_t N = 1) const noexcept {
     if (N >= size())
       return *this;
     return drop_front(size() - N);
   }
 
   // equals - Check for element-wise equality.
-  bool equals(ArrayRefBase<QualifiedT> RHS) const {
+  bool equals(ArrayRefBase<QualifiedT> RHS) const noexcept {
     if (Length != RHS.Length)
       return false;
     auto First1 = begin();
diff --git a/libc/utils/FPUtil/BasicOperations.h b/libc/utils/FPUtil/BasicOperations.h
index 43ccd12fdb70e..877119dea5e69 100644
--- a/libc/utils/FPUtil/BasicOperations.h
+++ b/libc/utils/FPUtil/BasicOperations.h
@@ -18,7 +18,7 @@ namespace fputil {
 
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T abs(T x) {
+static inline T abs(T x) noexcept {
   FPBits<T> bits(x);
   bits.setSign(0);
   return T(bits);
@@ -26,7 +26,7 @@ static inline T abs(T x) {
 
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T fmin(T x, T y) {
+static inline T fmin(T x, T y) noexcept {
   FPBits<T> bitx(x), bity(y);
 
   if (bitx.isNaN()) {
@@ -45,7 +45,7 @@ static inline T fmin(T x, T y) {
 
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T fmax(T x, T y) {
+static inline T fmax(T x, T y) noexcept {
   FPBits<T> bitx(x), bity(y);
 
   if (bitx.isNaN()) {
diff --git a/libc/utils/FPUtil/DivisionAndRemainderOperations.h b/libc/utils/FPUtil/DivisionAndRemainderOperations.h
index d23a8daabbe63..9493b408b547a 100644
--- a/libc/utils/FPUtil/DivisionAndRemainderOperations.h
+++ b/libc/utils/FPUtil/DivisionAndRemainderOperations.h
@@ -24,7 +24,7 @@ static constexpr int quotientLSBBits = 3;
 // to evaluate the quotient and remainder.
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T remquo(T x, T y, int &q) {
+static inline T remquo(T x, T y, int &q) noexcept {
   FPBits<T> xbits(x), ybits(y);
   if (xbits.isNaN())
     return x;
diff --git a/libc/utils/FPUtil/FPBits.h b/libc/utils/FPUtil/FPBits.h
index 9ee870dc9983d..fca93cfc04081 100644
--- a/libc/utils/FPUtil/FPBits.h
+++ b/libc/utils/FPUtil/FPBits.h
@@ -48,32 +48,34 @@ template <typename T> union FPBits {
 
   UIntType bits;
 
-  void setMantissa(UIntType mantVal) {
+  void setMantissa(UIntType mantVal) noexcept {
     mantVal &= (FloatProp::mantissaMask);
     bits &= ~(FloatProp::mantissaMask);
     bits |= mantVal;
   }
 
-  UIntType getMantissa() const { return bits & FloatProp::mantissaMask; }
+  UIntType getMantissa() const noexcept {
+    return bits & FloatProp::mantissaMask;
+  }
 
-  void setUnbiasedExponent(UIntType expVal) {
+  void setUnbiasedExponent(UIntType expVal) noexcept {
     expVal = (expVal << (FloatProp::mantissaWidth)) & FloatProp::exponentMask;
     bits &= ~(FloatProp::exponentMask);
     bits |= expVal;
   }
 
-  uint16_t getUnbiasedExponent() const {
+  uint16_t getUnbiasedExponent() const noexcept {
     return uint16_t((bits & FloatProp::exponentMask) >>
                     (FloatProp::mantissaWidth));
   }
 
-  void setSign(bool signVal) {
+  void setSign(bool signVal) noexcept {
     bits &= ~(FloatProp::signMask);
     UIntType sign = UIntType(signVal) << (FloatProp::bitWidth - 1);
     bits |= sign;
   }
 
-  bool getSign() const {
+  bool getSign() const noexcept {
     return ((bits & FloatProp::signMask) >> (FloatProp::bitWidth - 1));
   }
   T val;
@@ -106,43 +108,47 @@ template <typename T> union FPBits {
 
   explicit operator T() { return val; }
 
-  UIntType uintval() const { return bits; }
+  UIntType uintval() const noexcept { return bits; }
 
-  int getExponent() const { return int(getUnbiasedExponent()) - exponentBias; }
+  int getExponent() const noexcept {
+    return int(getUnbiasedExponent()) - exponentBias;
+  }
 
-  bool isZero() const {
+  bool isZero() const noexcept {
     return getMantissa() == 0 && getUnbiasedExponent() == 0;
   }
 
-  bool isInf() const {
+  bool isInf() const noexcept {
     return getMantissa() == 0 && getUnbiasedExponent() == maxExponent;
   }
 
-  bool isNaN() const {
+  bool isNaN() const noexcept {
     return getUnbiasedExponent() == maxExponent && getMantissa() != 0;
   }
 
-  bool isInfOrNaN() const { return getUnbiasedExponent() == maxExponent; }
+  bool isInfOrNaN() const noexcept {
+    return getUnbiasedExponent() == maxExponent;
+  }
 
-  static FPBits<T> zero() { return FPBits(); }
+  static FPBits<T> zero() noexcept { return FPBits(); }
 
-  static FPBits<T> negZero() {
+  static FPBits<T> negZero() noexcept {
     return FPBits(UIntType(1) << (sizeof(UIntType) * 8 - 1));
   }
 
-  static FPBits<T> inf() {
+  static FPBits<T> inf() noexcept {
     FPBits<T> bits;
     bits.setUnbiasedExponent(maxExponent);
     return bits;
   }
 
-  static FPBits<T> negInf() {
+  static FPBits<T> negInf() noexcept {
     FPBits<T> bits = inf();
     bits.setSign(1);
     return bits;
   }
 
-  static T buildNaN(UIntType v) {
+  static T buildNaN(UIntType v) noexcept {
     FPBits<T> bits = inf();
     bits.setMantissa(v);
     return T(bits);
diff --git a/libc/utils/FPUtil/Hypot.h b/libc/utils/FPUtil/Hypot.h
index 8d108a74761de..a3983dafc6ce8 100644
--- a/libc/utils/FPUtil/Hypot.h
+++ b/libc/utils/FPUtil/Hypot.h
@@ -18,10 +18,10 @@ namespace fputil {
 
 namespace internal {
 
-template <typename T> static inline T findLeadingOne(T mant, int &shift_length);
+template <typename T> static inline T findLeadingOne(T mant, int &shift_length) noexcept;
 
 template <>
-inline uint32_t findLeadingOne<uint32_t>(uint32_t mant, int &shift_length) {
+inline uint32_t findLeadingOne<uint32_t>(uint32_t mant, int &shift_length) noexcept {
   shift_length = 0;
   constexpr int nsteps = 5;
   constexpr uint32_t bounds[nsteps] = {1 << 16, 1 << 8, 1 << 4, 1 << 2, 1 << 1};
@@ -36,7 +36,7 @@ inline uint32_t findLeadingOne<uint32_t>(uint32_t mant, int &shift_length) {
 }
 
 template <>
-inline uint64_t findLeadingOne<uint64_t>(uint64_t mant, int &shift_length) {
+inline uint64_t findLeadingOne<uint64_t>(uint64_t mant, int &shift_length) noexcept {
   shift_length = 0;
   constexpr int nsteps = 6;
   constexpr uint64_t bounds[nsteps] = {1ULL << 32, 1ULL << 16, 1ULL << 8,
@@ -117,7 +117,7 @@ template <> struct DoubleLength<uint64_t> { using Type = __uint128_t; };
 //
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T hypot(T x, T y) {
+static inline T hypot(T x, T y) noexcept {
   using FPBits_t = FPBits<T>;
   using UIntType = typename FPBits<T>::UIntType;
   using DUIntType = typename DoubleLength<UIntType>::Type;
diff --git a/libc/utils/FPUtil/LongDoubleBitsX86.h b/libc/utils/FPUtil/LongDoubleBitsX86.h
index ce7fdb1b0fa8a..04c155b48a41f 100644
--- a/libc/utils/FPUtil/LongDoubleBitsX86.h
+++ b/libc/utils/FPUtil/LongDoubleBitsX86.h
@@ -43,43 +43,45 @@ template <> union FPBits<long double> {
 
   UIntType bits;
 
-  void setMantissa(UIntType mantVal) {
+  void setMantissa(UIntType mantVal) noexcept {
     mantVal &= (FloatProp::mantissaMask);
     bits &= ~(FloatProp::mantissaMask);
     bits |= mantVal;
   }
 
-  UIntType getMantissa() const { return bits & FloatProp::mantissaMask; }
+  UIntType getMantissa() const noexcept {
+    return bits & FloatProp::mantissaMask;
+  }
 
-  void setUnbiasedExponent(UIntType expVal) {
+  void setUnbiasedExponent(UIntType expVal) noexcept {
     expVal = (expVal << (FloatProp::bitWidth - 1 - FloatProp::exponentWidth)) &
              FloatProp::exponentMask;
     bits &= ~(FloatProp::exponentMask);
     bits |= expVal;
   }
 
-  uint16_t getUnbiasedExponent() const {
+  uint16_t getUnbiasedExponent() const noexcept {
     return uint16_t((bits & FloatProp::exponentMask) >>
                     (FloatProp::bitWidth - 1 - FloatProp::exponentWidth));
   }
 
-  void setImplicitBit(bool implicitVal) {
+  void setImplicitBit(bool implicitVal) noexcept {
     bits &= ~(UIntType(1) << FloatProp::mantissaWidth);
     bits |= (UIntType(implicitVal) << FloatProp::mantissaWidth);
   }
 
-  bool getImplicitBit() const {
+  bool getImplicitBit() const noexcept {
     return ((bits & (UIntType(1) << FloatProp::mantissaWidth)) >>
             FloatProp::mantissaWidth);
   }
 
-  void setSign(bool signVal) {
+  void setSign(bool signVal) noexcept {
     bits &= ~(FloatProp::signMask);
     UIntType sign1 = UIntType(signVal) << (FloatProp::bitWidth - 1);
     bits |= sign1;
   }
 
-  bool getSign() const {
+  bool getSign() const noexcept {
     return ((bits & FloatProp::signMask) >> (FloatProp::bitWidth - 1));
   }
 
@@ -106,23 +108,23 @@ template <> union FPBits<long double> {
     return bits & mask;
   }
 
-  int getExponent() const {
+  int getExponent() const noexcept {
     if (getUnbiasedExponent() == 0)
       return int(1) - exponentBias;
     return int(getUnbiasedExponent()) - exponentBias;
   }
 
-  bool isZero() const {
+  bool isZero() const noexcept {
     return getUnbiasedExponent() == 0 && getMantissa() == 0 &&
            getImplicitBit() == 0;
   }
 
-  bool isInf() const {
+  bool isInf() const noexcept {
     return getUnbiasedExponent() == maxExponent && getMantissa() == 0 &&
            getImplicitBit() == 1;
   }
 
-  bool isNaN() const {
+  bool isNaN() const noexcept {
     if (getUnbiasedExponent() == maxExponent) {
       return (getImplicitBit() == 0) || getMantissa() != 0;
     } else if (getUnbiasedExponent() != 0) {
@@ -131,29 +133,31 @@ template <> union FPBits<long double> {
     return false;
   }
 
-  bool isInfOrNaN() const {
+  bool isInfOrNaN() const noexcept {
     return (getUnbiasedExponent() == maxExponent) ||
            (getUnbiasedExponent() != 0 && getImplicitBit() == 0);
   }
 
   // Methods below this are used by tests.
 
-  static FPBits<long double> zero() { return FPBits<long double>(0.0l); }
+  static FPBits<long double> zero() noexcept {
+    return FPBits<long double>(0.0l);
+  }
 
-  static FPBits<long double> negZero() {
+  static FPBits<long double> negZero() noexcept {
     FPBits<long double> bits(0.0l);
     bits.setSign(1);
     return bits;
   }
 
-  static FPBits<long double> inf() {
+  static FPBits<long double> inf() noexcept {
     FPBits<long double> bits(0.0l);
     bits.setUnbiasedExponent(maxExponent);
     bits.setImplicitBit(1);
     return bits;
   }
 
-  static FPBits<long double> negInf() {
+  static FPBits<long double> negInf() noexcept {
     FPBits<long double> bits(0.0l);
     bits.setUnbiasedExponent(maxExponent);
     bits.setImplicitBit(1);
@@ -161,7 +165,7 @@ template <> union FPBits<long double> {
     return bits;
   }
 
-  static long double buildNaN(UIntType v) {
+  static long double buildNaN(UIntType v) noexcept {
     FPBits<long double> bits(0.0l);
     bits.setUnbiasedExponent(maxExponent);
     bits.setImplicitBit(1);
diff --git a/libc/utils/FPUtil/ManipulationFunctions.h b/libc/utils/FPUtil/ManipulationFunctions.h
index 545e5f0f24288..ee06166c46b1a 100644
--- a/libc/utils/FPUtil/ManipulationFunctions.h
+++ b/libc/utils/FPUtil/ManipulationFunctions.h
@@ -24,7 +24,7 @@ namespace fputil {
 
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T frexp(T x, int &exp) {
+static inline T frexp(T x, int &exp) noexcept {
   FPBits<T> bits(x);
   if (bits.isInfOrNaN())
     return x;
@@ -41,7 +41,7 @@ static inline T frexp(T x, int &exp) {
 
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T modf(T x, T &iptr) {
+static inline T modf(T x, T &iptr) noexcept {
   FPBits<T> bits(x);
   if (bits.isZero() || bits.isNaN()) {
     iptr = x;
@@ -63,7 +63,7 @@ static inline T modf(T x, T &iptr) {
 
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T copysign(T x, T y) {
+static inline T copysign(T x, T y) noexcept {
   FPBits<T> xbits(x);
   xbits.setSign(FPBits<T>(y).getSign());
   return T(xbits);
@@ -71,7 +71,7 @@ static inline T copysign(T x, T y) {
 
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline int ilogb(T x) {
+static inline int ilogb(T x) noexcept {
   // TODO: Raise appropriate floating point exceptions and set errno to the
   // an appropriate error value wherever relevant.
   FPBits<T> bits(x);
@@ -100,7 +100,7 @@ static inline int ilogb(T x) {
 
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T logb(T x) {
+static inline T logb(T x) noexcept {
   FPBits<T> bits(x);
   if (bits.isZero()) {
     // TODO(Floating point exception): Raise div-by-zero exception.
@@ -119,7 +119,7 @@ static inline T logb(T x) {
 
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T ldexp(T x, int exp) {
+static inline T ldexp(T x, int exp) noexcept {
   FPBits<T> bits(x);
   if (bits.isZero() || bits.isInfOrNaN() || exp == 0)
     return x;
@@ -146,7 +146,7 @@ static inline T ldexp(T x, int exp) {
 
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T nextafter(T from, T to) {
+static inline T nextafter(T from, T to) noexcept {
   FPBits<T> fromBits(from);
   if (fromBits.isNaN())
     return from;
diff --git a/libc/utils/FPUtil/NearestIntegerOperations.h b/libc/utils/FPUtil/NearestIntegerOperations.h
index 8dc4e23ce75c1..cc0b5142197ba 100644
--- a/libc/utils/FPUtil/NearestIntegerOperations.h
+++ b/libc/utils/FPUtil/NearestIntegerOperations.h
@@ -24,7 +24,7 @@ namespace fputil {
 
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T trunc(T x) {
+static inline T trunc(T x) noexcept {
   FPBits<T> bits(x);
 
   // If x is infinity or NaN, return it.
@@ -56,7 +56,7 @@ static inline T trunc(T x) {
 
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T ceil(T x) {
+static inline T ceil(T x) noexcept {
   FPBits<T> bits(x);
 
   // If x is infinity NaN or zero, return it.
@@ -95,7 +95,7 @@ static inline T ceil(T x) {
 
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T floor(T x) {
+static inline T floor(T x) noexcept {
   FPBits<T> bits(x);
   if (bits.getSign()) {
     return -ceil(-x);
@@ -106,7 +106,7 @@ static inline T floor(T x) {
 
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T round(T x) {
+static inline T round(T x) noexcept {
   using UIntType = typename FPBits<T>::UIntType;
   FPBits<T> bits(x);
 
@@ -158,7 +158,7 @@ static inline T round(T x) {
 
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T roundUsingCurrentRoundingMode(T x) {
+static inline T roundUsingCurrentRoundingMode(T x) noexcept {
   using UIntType = typename FPBits<T>::UIntType;
   FPBits<T> bits(x);
 
@@ -240,7 +240,7 @@ template <typename F, typename I,
           cpp::EnableIfType<cpp::IsFloatingPointType<F>::Value &&
                                 cpp::IsIntegral<I>::Value,
                             int> = 0>
-static inline I roundedFloatToSignedInteger(F x) {
+static inline I roundedFloatToSignedInteger(F x) noexcept {
   constexpr I IntegerMin = (I(1) << (sizeof(I) * 8 - 1));
   constexpr I IntegerMax = -(IntegerMin + 1);
   FPBits<F> bits(x);
@@ -284,7 +284,7 @@ template <typename F, typename I,
           cpp::EnableIfType<cpp::IsFloatingPointType<F>::Value &&
                                 cpp::IsIntegral<I>::Value,
                             int> = 0>
-static inline I roundToSignedInteger(F x) {
+static inline I roundToSignedInteger(F x) noexcept {
   return internal::roundedFloatToSignedInteger<F, I>(round(x));
 }
 
@@ -292,7 +292,7 @@ template <typename F, typename I,
           cpp::EnableIfType<cpp::IsFloatingPointType<F>::Value &&
                                 cpp::IsIntegral<I>::Value,
                             int> = 0>
-static inline I roundToSignedIntegerUsingCurrentRoundingMode(F x) {
+static inline I roundToSignedIntegerUsingCurrentRoundingMode(F x) noexcept {
   return internal::roundedFloatToSignedInteger<F, I>(
       roundUsingCurrentRoundingMode(x));
 }
diff --git a/libc/utils/FPUtil/NextAfterLongDoubleX86.h b/libc/utils/FPUtil/NextAfterLongDoubleX86.h
index 80ca9ad084cb2..ea91c02140ffa 100644
--- a/libc/utils/FPUtil/NextAfterLongDoubleX86.h
+++ b/libc/utils/FPUtil/NextAfterLongDoubleX86.h
@@ -16,7 +16,7 @@
 namespace __llvm_libc {
 namespace fputil {
 
-static inline long double nextafter(long double from, long double to) {
+static inline long double nextafter(long double from, long double to) noexcept {
   using FPBits = FPBits<long double>;
   FPBits fromBits(from);
   if (fromBits.isNaN())
diff --git a/libc/utils/FPUtil/NormalFloat.h b/libc/utils/FPUtil/NormalFloat.h
index 2d50e88db9167..024d3e6f8f0d2 100644
--- a/libc/utils/FPUtil/NormalFloat.h
+++ b/libc/utils/FPUtil/NormalFloat.h
@@ -45,7 +45,7 @@ template <typename T> struct NormalFloat {
   bool sign;
 
   NormalFloat(int32_t e, UIntType m, bool s)
-      : exponent(e), mantissa(m), sign(s) {
+      : exponent(e), mantissa(m), sign(s) noexcept {
     if (mantissa >= one)
       return;
 
@@ -61,7 +61,7 @@ template <typename T> struct NormalFloat {
   // Compares this normalized number with another normalized number.
   // Returns -1 is this number is less than |other|, 0 if this number is equal
   // to |other|, and 1 if this number is greater than |other|.
-  int cmp(const NormalFloat<T> &other) const {
+  int cmp(const NormalFloat<T> &other) const noexcept {
     if (sign != other.sign)
       return sign ? -1 : 1;
 
@@ -82,7 +82,7 @@ template <typename T> struct NormalFloat {
   // Returns a new normalized floating point number which is equal in value
   // to this number multiplied by 2^e. That is:
   //     new = this *  2^e
-  NormalFloat<T> mul2(int e) const {
+  NormalFloat<T> mul2(int e) const noexcept {
     NormalFloat<T> result = *this;
     result.exponent += e;
     return result;
@@ -138,7 +138,7 @@ template <typename T> struct NormalFloat {
   }
 
 private:
-  void initFromBits(FPBits<T> bits) {
+  void initFromBits(FPBits<T> bits) noexcept {
     sign = bits.getSign();
 
     if (bits.isInfOrNaN() || bits.isZero()) {
@@ -160,7 +160,7 @@ template <typename T> struct NormalFloat {
     }
   }
 
-  unsigned evaluateNormalizationShift(UIntType m) {
+  unsigned evaluateNormalizationShift(UIntType m) noexcept {
     unsigned shift = 0;
     for (; (one & m) == 0 && (shift < MantissaWidth<T>::value);
          m <<= 1, ++shift)
@@ -171,7 +171,7 @@ template <typename T> struct NormalFloat {
 
 #ifdef SPECIAL_X86_LONG_DOUBLE
 template <>
-inline void NormalFloat<long double>::initFromBits(FPBits<long double> bits) {
+inline void NormalFloat<long double>::initFromBits(FPBits<long double> bits) noexcept {
   sign = bits.getSign();
 
   if (bits.isInfOrNaN() || bits.isZero()) {
diff --git a/libc/utils/FPUtil/PolyEval.h b/libc/utils/FPUtil/PolyEval.h
index ce8377fe895a1..313f57bcd032c 100644
--- a/libc/utils/FPUtil/PolyEval.h
+++ b/libc/utils/FPUtil/PolyEval.h
@@ -24,10 +24,12 @@
 namespace __llvm_libc {
 namespace fputil {
 
-template <typename T> static inline T polyeval(T x, T a0) { return a0; }
+template <typename T> static inline T polyeval(T x, T a0) noexcept {
+  return a0;
+}
 
 template <typename T, typename... Ts>
-static inline T polyeval(T x, T a0, Ts... a) {
+static inline T polyeval(T x, T a0, Ts... a) noexcept {
   return fma(x, polyeval(x, a...), a0);
 }
 
@@ -39,10 +41,12 @@ static inline T polyeval(T x, T a0, Ts... a) {
 namespace __llvm_libc {
 namespace fputil {
 
-template <typename T> static inline T polyeval(T x, T a0) { return a0; }
+template <typename T> static inline T polyeval(T x, T a0) noexcept {
+  return a0;
+}
 
 template <typename T, typename... Ts>
-static inline T polyeval(T x, T a0, Ts... a) {
+static inline T polyeval(T x, T a0, Ts... a) noexcept {
   return x * polyeval(x, a...) + a0;
 }
 
diff --git a/libc/utils/FPUtil/Sqrt.h b/libc/utils/FPUtil/Sqrt.h
index b977bc2ef8773..a15a0eb4cf9cb 100644
--- a/libc/utils/FPUtil/Sqrt.h
+++ b/libc/utils/FPUtil/Sqrt.h
@@ -21,9 +21,10 @@ namespace internal {
 
 template <typename T>
 static inline void normalize(int &exponent,
-                             typename FPBits<T>::UIntType &mantissa);
+                             typename FPBits<T>::UIntType &mantissa) noexcept;
 
-template <> inline void normalize<float>(int &exponent, uint32_t &mantissa) {
+template <>
+inline void normalize<float>(int &exponent, uint32_t &mantissa) noexcept {
   // Use binary search to shift the leading 1 bit.
   // With MantissaWidth<float> = 23, it will take
   // ceil(log2(23)) = 5 steps checking the mantissa bits as followed:
@@ -45,7 +46,8 @@ template <> inline void normalize<float>(int &exponent, uint32_t &mantissa) {
   }
 }
 
-template <> inline void normalize<double>(int &exponent, uint64_t &mantissa) {
+template <>
+inline void normalize<double>(int &exponent, uint64_t &mantissa) noexcept {
   // Use binary search to shift the leading 1 bit similar to float.
   // With MantissaWidth<double> = 52, it will take
   // ceil(log2(52)) = 6 steps checking the mantissa bits.
@@ -64,12 +66,13 @@ template <> inline void normalize<double>(int &exponent, uint64_t &mantissa) {
 
 #ifdef LONG_DOUBLE_IS_DOUBLE
 template <>
-inline void normalize<long double>(int &exponent, uint64_t &mantissa) {
+inline void normalize<long double>(int &exponent, uint64_t &mantissa) noexcept {
   normalize<double>(exponent, mantissa);
 }
 #elif !defined(SPECIAL_X86_LONG_DOUBLE)
 template <>
-inline void normalize<long double>(int &exponent, __uint128_t &mantissa) {
+inline void normalize<long double>(int &exponent,
+                                   __uint128_t &mantissa) noexcept {
   // Use binary search to shift the leading 1 bit similar to float.
   // With MantissaWidth<long double> = 112, it will take
   // ceil(log2(112)) = 7 steps checking the mantissa bits.
@@ -95,7 +98,7 @@ inline void normalize<long double>(int &exponent, __uint128_t &mantissa) {
 // Shift-and-add algorithm.
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T sqrt(T x) {
+static inline T sqrt(T x) noexcept {
   using UIntType = typename FPBits<T>::UIntType;
   constexpr UIntType One = UIntType(1) << MantissaWidth<T>::value;
 
diff --git a/libc/utils/FPUtil/SqrtLongDoubleX86.h b/libc/utils/FPUtil/SqrtLongDoubleX86.h
index 58326183678b8..2b21647550f3c 100644
--- a/libc/utils/FPUtil/SqrtLongDoubleX86.h
+++ b/libc/utils/FPUtil/SqrtLongDoubleX86.h
@@ -20,7 +20,8 @@ namespace fputil {
 namespace internal {
 
 template <>
-inline void normalize<long double>(int &exponent, __uint128_t &mantissa) {
+inline void normalize<long double>(int &exponent,
+                                   __uint128_t &mantissa) noexcept {
   // Use binary search to shift the leading 1 bit similar to float.
   // With MantissaWidth<long double> = 63, it will take
   // ceil(log2(63)) = 6 steps checking the mantissa bits.
@@ -42,7 +43,7 @@ inline void normalize<long double>(int &exponent, __uint128_t &mantissa) {
 
 // Correctly rounded SQRT with round to nearest, ties to even.
 // Shift-and-add algorithm.
-template <> inline long double sqrt<long double, 0>(long double x) {
+template <> inline long double sqrt<long double, 0>(long double x) noexcept {
   using UIntType = typename FPBits<long double>::UIntType;
   constexpr UIntType One = UIntType(1)
                            << int(MantissaWidth<long double>::value);
diff --git a/llvm/include/llvm/Support/Compiler.h b/llvm/include/llvm/Support/Compiler.h
index 57052b596edbe..ec90f75719470 100644
--- a/llvm/include/llvm/Support/Compiler.h
+++ b/llvm/include/llvm/Support/Compiler.h
@@ -246,8 +246,10 @@
 #define LLVM_ATTRIBUTE_NORETURN __attribute__((noreturn))
 #elif defined(_MSC_VER)
 #define LLVM_ATTRIBUTE_NORETURN __declspec(noreturn)
+#elif __cplusplus
+#define LLVM_ATTRIBUTE_NORETURN [[noreturn]]
 #else
-#define LLVM_ATTRIBUTE_NORETURN
+#define LLVM_ATTRIBUTE_NORETURN _Noreturn
 #endif
 
 #if __has_attribute(returns_nonnull) || LLVM_GNUC_PREREQ(4, 9, 0)
diff --git a/llvm/lib/TableGen/Error.cpp b/llvm/lib/TableGen/Error.cpp
index 6104573b4b25b..cf7c4dd129499 100644
--- a/llvm/lib/TableGen/Error.cpp
+++ b/llvm/lib/TableGen/Error.cpp
@@ -11,11 +11,11 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "llvm/TableGen/Error.h"
 #include "llvm/ADT/Twine.h"
-#include "llvm/Support/raw_ostream.h"
 #include "llvm/Support/Signals.h"
 #include "llvm/Support/WithColor.h"
-#include "llvm/TableGen/Error.h"
+#include "llvm/Support/raw_ostream.h"
 #include "llvm/TableGen/Record.h"
 #include <cstdlib>
 
@@ -25,7 +25,7 @@ SourceMgr SrcMgr;
 unsigned ErrorsPrinted = 0;
 
 static void PrintMessage(ArrayRef<SMLoc> Loc, SourceMgr::DiagKind Kind,
-                         const Twine &Msg) {
+                         const Twine &Msg) noexcept {
   // Count the total number of errors printed.
   // This is used to exit with an error code if there were any errors.
   if (Kind == SourceMgr::DK_Error)
@@ -42,24 +42,23 @@ static void PrintMessage(ArrayRef<SMLoc> Loc, SourceMgr::DiagKind Kind,
 
 // Functions to print notes.
 
-void PrintNote(const Twine &Msg) {
-  WithColor::note() << Msg << "\n";
-}
+void PrintNote(const Twine &Msg) noexcept { WithColor::note() << Msg << "\n"; }
 
-void PrintNote(ArrayRef<SMLoc> NoteLoc, const Twine &Msg) {
+void PrintNote(ArrayRef<SMLoc> NoteLoc, const Twine &Msg) noexcept {
   PrintMessage(NoteLoc, SourceMgr::DK_Note, Msg);
 }
 
 // Functions to print fatal notes.
 
-void PrintFatalNote(const Twine &Msg) {
+LLVM_ATTRIBUTE_NORETURN void PrintFatalNote(const Twine &Msg) noexcept {
   PrintNote(Msg);
   // The following call runs the file cleanup handlers.
   sys::RunInterruptHandlers();
   std::exit(1);
 }
 
-void PrintFatalNote(ArrayRef<SMLoc> NoteLoc, const Twine &Msg) {
+LLVM_ATTRIBUTE_NORETURN void PrintFatalNote(ArrayRef<SMLoc> NoteLoc,
+                                 const Twine &Msg) noexcept {
   PrintNote(NoteLoc, Msg);
   // The following call runs the file cleanup handlers.
   sys::RunInterruptHandlers();
@@ -68,7 +67,7 @@ void PrintFatalNote(ArrayRef<SMLoc> NoteLoc, const Twine &Msg) {
 
 // This method takes a Record and uses the source location
 // stored in it.
-void PrintFatalNote(const Record *Rec, const Twine &Msg) {
+LLVM_ATTRIBUTE_NORETURN void PrintFatalNote(const Record *Rec, const Twine &Msg) noexcept {
   PrintNote(Rec->getLoc(), Msg);
   // The following call runs the file cleanup handlers.
   sys::RunInterruptHandlers();
@@ -77,7 +76,8 @@ void PrintFatalNote(const Record *Rec, const Twine &Msg) {
 
 // This method takes a RecordVal and uses the source location
 // stored in it.
-void PrintFatalNote(const RecordVal *RecVal, const Twine &Msg) {
+LLVM_ATTRIBUTE_NORETURN void PrintFatalNote(const RecordVal *RecVal,
+                                 const Twine &Msg) noexcept {
   PrintNote(RecVal->getLoc(), Msg);
   // The following call runs the file cleanup handlers.
   sys::RunInterruptHandlers();
@@ -86,50 +86,55 @@ void PrintFatalNote(const RecordVal *RecVal, const Twine &Msg) {
 
 // Functions to print warnings.
 
-void PrintWarning(const Twine &Msg) { WithColor::warning() << Msg << "\n"; }
+void PrintWarning(const Twine &Msg) noexcept {
+  WithColor::warning() << Msg << "\n";
+}
 
-void PrintWarning(ArrayRef<SMLoc> WarningLoc, const Twine &Msg) {
+void PrintWarning(ArrayRef<SMLoc> WarningLoc, const Twine &Msg) noexcept {
   PrintMessage(WarningLoc, SourceMgr::DK_Warning, Msg);
 }
 
-void PrintWarning(const char *Loc, const Twine &Msg) {
+void PrintWarning(const char *Loc, const Twine &Msg) noexcept {
   SrcMgr.PrintMessage(SMLoc::getFromPointer(Loc), SourceMgr::DK_Warning, Msg);
 }
 
 // Functions to print errors.
 
-void PrintError(const Twine &Msg) { WithColor::error() << Msg << "\n"; }
+void PrintError(const Twine &Msg) noexcept {
+  WithColor::error() << Msg << "\n";
+}
 
-void PrintError(ArrayRef<SMLoc> ErrorLoc, const Twine &Msg) {
+void PrintError(ArrayRef<SMLoc> ErrorLoc, const Twine &Msg) noexcept {
   PrintMessage(ErrorLoc, SourceMgr::DK_Error, Msg);
 }
 
-void PrintError(const char *Loc, const Twine &Msg) {
+void PrintError(const char *Loc, const Twine &Msg) noexcept {
   SrcMgr.PrintMessage(SMLoc::getFromPointer(Loc), SourceMgr::DK_Error, Msg);
 }
 
 // This method takes a Record and uses the source location
 // stored in it.
-void PrintError(const Record *Rec, const Twine &Msg) {
+void PrintError(const Record *Rec, const Twine &Msg) noexcept {
   PrintMessage(Rec->getLoc(), SourceMgr::DK_Error, Msg);
 }
 
 // This method takes a RecordVal and uses the source location
 // stored in it.
-void PrintError(const RecordVal *RecVal, const Twine &Msg) {
+void PrintError(const RecordVal *RecVal, const Twine &Msg) noexcept {
   PrintMessage(RecVal->getLoc(), SourceMgr::DK_Error, Msg);
 }
 
 // Functions to print fatal errors.
 
-void PrintFatalError(const Twine &Msg) {
+[[noreturn]] void PrintFatalError(const Twine &Msg) noexcept {
   PrintError(Msg);
   // The following call runs the file cleanup handlers.
   sys::RunInterruptHandlers();
   std::exit(1);
 }
 
-void PrintFatalError(ArrayRef<SMLoc> ErrorLoc, const Twine &Msg) {
+[[noreturn]] void PrintFatalError(ArrayRef<SMLoc> ErrorLoc,
+                                  const Twine &Msg) noexcept {
   PrintError(ErrorLoc, Msg);
   // The following call runs the file cleanup handlers.
   sys::RunInterruptHandlers();
@@ -138,7 +143,8 @@ void PrintFatalError(ArrayRef<SMLoc> ErrorLoc, const Twine &Msg) {
 
 // This method takes a Record and uses the source location
 // stored in it.
-void PrintFatalError(const Record *Rec, const Twine &Msg) {
+[[noreturn]] void PrintFatalError(const Record *Rec,
+                                  const Twine &Msg) noexcept {
   PrintError(Rec->getLoc(), Msg);
   // The following call runs the file cleanup handlers.
   sys::RunInterruptHandlers();
@@ -147,7 +153,8 @@ void PrintFatalError(const Record *Rec, const Twine &Msg) {
 
 // This method takes a RecordVal and uses the source location
 // stored in it.
-void PrintFatalError(const RecordVal *RecVal, const Twine &Msg) {
+[[noreturn]] void PrintFatalError(const RecordVal *RecVal,
+                                  const Twine &Msg) noexcept {
   PrintError(RecVal->getLoc(), Msg);
   // The following call runs the file cleanup handlers.
   sys::RunInterruptHandlers();
@@ -156,9 +163,9 @@ void PrintFatalError(const RecordVal *RecVal, const Twine &Msg) {
 
 // Check an assertion: Obtain the condition value and be sure it is true.
 // If not, print a nonfatal error along with the message.
-void CheckAssert(SMLoc Loc, Init *Condition, Init *Message) {
+void CheckAssert(SMLoc Loc, Init *Condition, Init *Message) noexcept {
   auto *CondValue = dyn_cast_or_null<IntInit>(
-                        Condition->convertInitializerTo(IntRecTy::get()));
+      Condition->convertInitializerTo(IntRecTy::get()));
   if (!CondValue)
     PrintError(Loc, "assert condition must of type bit, bits, or int.");
   else if (!CondValue->getValue()) {

From a287b4d1ac7756ca224b28a5aea38c2f5a8d579f Mon Sep 17 00:00:00 2001
From: Alfonso Gregory <83477269+gAlfonso-bit@users.noreply.github.com>
Date: Mon, 26 Jul 2021 13:28:33 -0400
Subject: [PATCH 08/17] Revert "math"

This reverts commit ca034214fcc63fe50d909dacb909fc51a7960b32.
---
 libc/src/math/ceil.h                  |  2 +-
 libc/src/math/ceilf.h                 |  2 +-
 libc/src/math/ceill.h                 |  2 +-
 libc/src/math/copysign.h              |  2 +-
 libc/src/math/copysignf.h             |  2 +-
 libc/src/math/copysignl.h             |  2 +-
 libc/src/math/cos.h                   |  2 +-
 libc/src/math/cosf.h                  |  2 +-
 libc/src/math/exp2f.h                 |  2 +-
 libc/src/math/expf.h                  |  2 +-
 libc/src/math/expm1f.h                |  2 +-
 libc/src/math/fabs.h                  |  2 +-
 libc/src/math/fabsf.h                 |  2 +-
 libc/src/math/fabsl.h                 |  2 +-
 libc/src/math/fdim.h                  |  2 +-
 libc/src/math/fdimf.h                 |  2 +-
 libc/src/math/fdiml.h                 |  2 +-
 libc/src/math/floor.h                 |  2 +-
 libc/src/math/floorf.h                |  2 +-
 libc/src/math/floorl.h                |  2 +-
 libc/src/math/fma.h                   |  2 +-
 libc/src/math/fmaf.h                  |  2 +-
 libc/src/math/fmax.h                  |  2 +-
 libc/src/math/fmaxf.h                 |  2 +-
 libc/src/math/fmaxl.h                 |  2 +-
 libc/src/math/fmin.h                  |  2 +-
 libc/src/math/fminf.h                 |  2 +-
 libc/src/math/fminl.h                 |  2 +-
 libc/src/math/frexp.h                 |  2 +-
 libc/src/math/frexpf.h                |  2 +-
 libc/src/math/frexpl.h                |  2 +-
 libc/src/math/generic/math_utils.h    | 34 +++++++++++----------------
 libc/src/math/generic/sincosf_utils.h | 12 ++++------
 libc/src/math/hypot.h                 |  2 +-
 libc/src/math/hypotf.h                |  2 +-
 libc/src/math/ilogb.h                 |  2 +-
 libc/src/math/ilogbf.h                |  2 +-
 libc/src/math/ilogbl.h                |  2 +-
 libc/src/math/ldexp.h                 |  2 +-
 libc/src/math/ldexpf.h                |  2 +-
 libc/src/math/ldexpl.h                |  2 +-
 libc/src/math/llrint.h                |  2 +-
 libc/src/math/llrintf.h               |  2 +-
 libc/src/math/llrintl.h               |  2 +-
 libc/src/math/llround.h               |  2 +-
 libc/src/math/llroundf.h              |  2 +-
 libc/src/math/llroundl.h              |  2 +-
 libc/src/math/logb.h                  |  2 +-
 libc/src/math/logbf.h                 |  2 +-
 libc/src/math/logbl.h                 |  2 +-
 libc/src/math/lrint.h                 |  2 +-
 libc/src/math/lrintf.h                |  2 +-
 libc/src/math/lrintl.h                |  2 +-
 libc/src/math/lround.h                |  2 +-
 libc/src/math/lroundf.h               |  2 +-
 libc/src/math/lroundl.h               |  2 +-
 libc/src/math/modf.h                  |  2 +-
 libc/src/math/modff.h                 |  2 +-
 libc/src/math/modfl.h                 |  2 +-
 libc/src/math/nearbyint.h             |  2 +-
 libc/src/math/nearbyintf.h            |  2 +-
 libc/src/math/nearbyintl.h            |  2 +-
 libc/src/math/nextafter.h             |  2 +-
 libc/src/math/nextafterf.h            |  2 +-
 libc/src/math/nextafterl.h            |  2 +-
 libc/src/math/remainder.h             |  2 +-
 libc/src/math/remainderf.h            |  2 +-
 libc/src/math/remainderl.h            |  2 +-
 libc/src/math/remquo.h                |  2 +-
 libc/src/math/remquof.h               |  2 +-
 libc/src/math/remquol.h               |  2 +-
 libc/src/math/rint.h                  |  2 +-
 libc/src/math/rintf.h                 |  2 +-
 libc/src/math/rintl.h                 |  2 +-
 libc/src/math/round.h                 |  2 +-
 libc/src/math/roundf.h                |  2 +-
 libc/src/math/roundl.h                |  2 +-
 libc/src/math/sin.h                   |  2 +-
 libc/src/math/sincosf.h               |  2 +-
 libc/src/math/sinf.h                  |  2 +-
 libc/src/math/sqrt.h                  |  2 +-
 libc/src/math/sqrtf.h                 |  2 +-
 libc/src/math/sqrtl.h                 |  2 +-
 libc/src/math/tan.h                   |  2 +-
 libc/src/math/trunc.h                 |  2 +-
 libc/src/math/truncf.h                |  2 +-
 libc/src/math/truncl.h                |  2 +-
 87 files changed, 104 insertions(+), 112 deletions(-)

diff --git a/libc/src/math/ceil.h b/libc/src/math/ceil.h
index b1a7e9b0fb70a..98188de20e405 100644
--- a/libc/src/math/ceil.h
+++ b/libc/src/math/ceil.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double ceil(double x) noexcept;
+double ceil(double x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/ceilf.h b/libc/src/math/ceilf.h
index 6f2add587808d..e8e64565052a6 100644
--- a/libc/src/math/ceilf.h
+++ b/libc/src/math/ceilf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float ceilf(float x) noexcept;
+float ceilf(float x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/ceill.h b/libc/src/math/ceill.h
index 22184f4b55e3d..8bf4c565c7d3b 100644
--- a/libc/src/math/ceill.h
+++ b/libc/src/math/ceill.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double ceill(long double x) noexcept;
+long double ceill(long double x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/copysign.h b/libc/src/math/copysign.h
index 21929390c36e2..edffe1b082fe0 100644
--- a/libc/src/math/copysign.h
+++ b/libc/src/math/copysign.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double copysign(double x, double y) noexcept;
+double copysign(double x, double y);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/copysignf.h b/libc/src/math/copysignf.h
index 5affaa796553a..5b7f1132252d6 100644
--- a/libc/src/math/copysignf.h
+++ b/libc/src/math/copysignf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float copysignf(float x, float y) noexcept;
+float copysignf(float x, float y);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/copysignl.h b/libc/src/math/copysignl.h
index e815c52708d38..4f48323c70141 100644
--- a/libc/src/math/copysignl.h
+++ b/libc/src/math/copysignl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double copysignl(long double x, long double y) noexcept;
+long double copysignl(long double x, long double y);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/cos.h b/libc/src/math/cos.h
index 71cb5504caabb..aca1d6d1e2281 100644
--- a/libc/src/math/cos.h
+++ b/libc/src/math/cos.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double cos(double x) noexcept;
+double cos(double x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/cosf.h b/libc/src/math/cosf.h
index f1b2e4f8b4a9a..1aaabe900ba88 100644
--- a/libc/src/math/cosf.h
+++ b/libc/src/math/cosf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float cosf(float x) noexcept;
+float cosf(float x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/exp2f.h b/libc/src/math/exp2f.h
index 9a7496d693331..c1f72b1b80fa8 100644
--- a/libc/src/math/exp2f.h
+++ b/libc/src/math/exp2f.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float exp2f(float x) noexcept;
+float exp2f(float x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/expf.h b/libc/src/math/expf.h
index 6dc96333d3d66..c61ce98e9ddcf 100644
--- a/libc/src/math/expf.h
+++ b/libc/src/math/expf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float expf(float x) noexcept;
+float expf(float x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/expm1f.h b/libc/src/math/expm1f.h
index d52fc9e1497e8..2577e4a492980 100644
--- a/libc/src/math/expm1f.h
+++ b/libc/src/math/expm1f.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float expm1f(float x) noexcept;
+float expm1f(float x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/fabs.h b/libc/src/math/fabs.h
index e4894213e90bc..424d2e01646b0 100644
--- a/libc/src/math/fabs.h
+++ b/libc/src/math/fabs.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double fabs(double x) noexcept;
+double fabs(double x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/fabsf.h b/libc/src/math/fabsf.h
index 0379397f9a95c..0ad97a027c6c8 100644
--- a/libc/src/math/fabsf.h
+++ b/libc/src/math/fabsf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float fabsf(float x) noexcept;
+float fabsf(float x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/fabsl.h b/libc/src/math/fabsl.h
index 5625dea600184..fa25b1ab564d7 100644
--- a/libc/src/math/fabsl.h
+++ b/libc/src/math/fabsl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double fabsl(long double x) noexcept;
+long double fabsl(long double x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/fdim.h b/libc/src/math/fdim.h
index 1dbabb3e2980a..f838c121e291c 100644
--- a/libc/src/math/fdim.h
+++ b/libc/src/math/fdim.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double fdim(double x, double y) noexcept;
+double fdim(double x, double y);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/fdimf.h b/libc/src/math/fdimf.h
index 8e5a650875efb..50c586c49cc39 100644
--- a/libc/src/math/fdimf.h
+++ b/libc/src/math/fdimf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float fdimf(float x, float y) noexcept;
+float fdimf(float x, float y);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/fdiml.h b/libc/src/math/fdiml.h
index 36b936054ec4c..6de261fe861a0 100644
--- a/libc/src/math/fdiml.h
+++ b/libc/src/math/fdiml.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double fdiml(long double x, long double y) noexcept;
+long double fdiml(long double x, long double y);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/floor.h b/libc/src/math/floor.h
index 7542f0f184f05..88a76ebf7d805 100644
--- a/libc/src/math/floor.h
+++ b/libc/src/math/floor.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double floor(double x) noexcept;
+double floor(double x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/floorf.h b/libc/src/math/floorf.h
index 2e4be43a63265..029df3ac5c9fe 100644
--- a/libc/src/math/floorf.h
+++ b/libc/src/math/floorf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float floorf(float x) noexcept;
+float floorf(float x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/floorl.h b/libc/src/math/floorl.h
index 96895f54438d1..224cc13ec6fa6 100644
--- a/libc/src/math/floorl.h
+++ b/libc/src/math/floorl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double floorl(long double x) noexcept;
+long double floorl(long double x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/fma.h b/libc/src/math/fma.h
index f8346f604ba70..fbc7f09ee2c74 100644
--- a/libc/src/math/fma.h
+++ b/libc/src/math/fma.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double fma(double x, double y, double z) noexcept;
+double fma(double x, double y, double z);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/fmaf.h b/libc/src/math/fmaf.h
index 89463d4999595..48fbb65d66506 100644
--- a/libc/src/math/fmaf.h
+++ b/libc/src/math/fmaf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float fmaf(float x, float y, float z) noexcept;
+float fmaf(float x, float y, float z);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/fmax.h b/libc/src/math/fmax.h
index b9697c8ecb8b7..9f057983d28bb 100644
--- a/libc/src/math/fmax.h
+++ b/libc/src/math/fmax.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double fmax(double x, double y) noexcept;
+double fmax(double x, double y);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/fmaxf.h b/libc/src/math/fmaxf.h
index dfaebf014f40c..e37df5cf9565d 100644
--- a/libc/src/math/fmaxf.h
+++ b/libc/src/math/fmaxf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float fmaxf(float x, float y) noexcept;
+float fmaxf(float x, float y);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/fmaxl.h b/libc/src/math/fmaxl.h
index 78f52a8893de8..41d80ba4aa52c 100644
--- a/libc/src/math/fmaxl.h
+++ b/libc/src/math/fmaxl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double fmaxl(long double x, long double y) noexcept;
+long double fmaxl(long double x, long double y);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/fmin.h b/libc/src/math/fmin.h
index 15c967f68120c..52334ee8e4560 100644
--- a/libc/src/math/fmin.h
+++ b/libc/src/math/fmin.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double fmin(double x, double y) noexcept;
+double fmin(double x, double y);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/fminf.h b/libc/src/math/fminf.h
index cf30993743874..62dad57d852aa 100644
--- a/libc/src/math/fminf.h
+++ b/libc/src/math/fminf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float fminf(float x, float y) noexcept;
+float fminf(float x, float y);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/fminl.h b/libc/src/math/fminl.h
index eae2d0d607e51..c19505c018283 100644
--- a/libc/src/math/fminl.h
+++ b/libc/src/math/fminl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double fminl(long double x, long double y) noexcept;
+long double fminl(long double x, long double y);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/frexp.h b/libc/src/math/frexp.h
index 71fe10fd1532c..9258243188360 100644
--- a/libc/src/math/frexp.h
+++ b/libc/src/math/frexp.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double frexp(double x, int *exp) noexcept;
+double frexp(double x, int *exp);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/frexpf.h b/libc/src/math/frexpf.h
index 534effa24b2e9..ed303d2c76dd5 100644
--- a/libc/src/math/frexpf.h
+++ b/libc/src/math/frexpf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float frexpf(float x, int *exp) noexcept;
+float frexpf(float x, int *exp);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/frexpl.h b/libc/src/math/frexpl.h
index e5e96494a2b8f..9f75c82b9034a 100644
--- a/libc/src/math/frexpl.h
+++ b/libc/src/math/frexpl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double frexpl(long double x, int *exp) noexcept;
+long double frexpl(long double x, int *exp);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/generic/math_utils.h b/libc/src/math/generic/math_utils.h
index e96b36f3e974c..4afddb04d6e43 100644
--- a/libc/src/math/generic/math_utils.h
+++ b/libc/src/math/generic/math_utils.h
@@ -18,29 +18,25 @@
 
 namespace __llvm_libc {
 
-static inline uint32_t as_uint32_bits(float x) noexcept {
+static inline uint32_t as_uint32_bits(float x) {
   return *reinterpret_cast<uint32_t *>(&x);
 }
 
-static inline uint64_t as_uint64_bits(double x) noexcept {
+static inline uint64_t as_uint64_bits(double x) {
   return *reinterpret_cast<uint64_t *>(&x);
 }
 
-static inline float as_float(uint32_t x) noexcept {
+static inline float as_float(uint32_t x) {
   return *reinterpret_cast<float *>(&x);
 }
 
-static inline double as_double(uint64_t x) noexcept {
+static inline double as_double(uint64_t x) {
   return *reinterpret_cast<double *>(&x);
 }
 
-static inline uint32_t top12_bits(float x) noexcept {
-  return as_uint32_bits(x) >> 20;
-}
+static inline uint32_t top12_bits(float x) { return as_uint32_bits(x) >> 20; }
 
-static inline uint32_t top12_bits(double x) noexcept {
-  return as_uint64_bits(x) >> 52;
-}
+static inline uint32_t top12_bits(double x) { return as_uint64_bits(x) >> 52; }
 
 // Values to trigger underflow and overflow.
 template <typename T> struct XFlowValues;
@@ -57,17 +53,17 @@ template <> struct XFlowValues<double> {
   static const double may_underflow_value;
 };
 
-template <typename T> static inline T with_errno(T x, int err) noexcept {
+template <typename T> static inline T with_errno(T x, int err) {
   if (math_errhandling & MATH_ERRNO)
     errno = err; // NOLINT
   return x;
 }
 
-template <typename T> static inline void force_eval(T x) noexcept {
+template <typename T> static inline void force_eval(T x) {
   volatile T y UNUSED = x;
 }
 
-template <typename T> static inline T opt_barrier(T x) noexcept {
+template <typename T> static inline T opt_barrier(T x) {
   volatile T y = x;
   return y;
 }
@@ -81,30 +77,28 @@ template <typename T>
 using EnableIfFloatOrDouble = cpp::EnableIfType<IsFloatOrDouble<T>::Value, int>;
 
 template <typename T, EnableIfFloatOrDouble<T> = 0>
-T xflow(uint32_t sign, T y) noexcept {
+T xflow(uint32_t sign, T y) {
   // Underflow happens when two extremely small values are multiplied.
   // Likewise, overflow happens when two large values are multiplied.
   y = opt_barrier(sign ? -y : y) * y;
   return with_errno(y, ERANGE);
 }
 
-template <typename T, EnableIfFloatOrDouble<T> = 0>
-T overflow(uint32_t sign) noexcept {
+template <typename T, EnableIfFloatOrDouble<T> = 0> T overflow(uint32_t sign) {
   return xflow(sign, XFlowValues<T>::overflow_value);
 }
 
-template <typename T, EnableIfFloatOrDouble<T> = 0>
-T underflow(uint32_t sign) noexcept {
+template <typename T, EnableIfFloatOrDouble<T> = 0> T underflow(uint32_t sign) {
   return xflow(sign, XFlowValues<T>::underflow_value);
 }
 
 template <typename T, EnableIfFloatOrDouble<T> = 0>
-T may_underflow(uint32_t sign) noexcept {
+T may_underflow(uint32_t sign) {
   return xflow(sign, XFlowValues<T>::may_underflow_value);
 }
 
 template <typename T, EnableIfFloatOrDouble<T> = 0>
-static constexpr float invalid(T x) {
+static inline constexpr float invalid(T x) {
   T y = (x - x) / (x - x);
   return isnan(x) ? y : with_errno(y, EDOM);
 }
diff --git a/libc/src/math/generic/sincosf_utils.h b/libc/src/math/generic/sincosf_utils.h
index a6fbb18a9214e..8c54cb9c1d904 100644
--- a/libc/src/math/generic/sincosf_utils.h
+++ b/libc/src/math/generic/sincosf_utils.h
@@ -36,7 +36,7 @@ extern const sincos_t __sincosf_table[2];
 extern const uint32_t __inv_pio4[];
 
 // Top 12 bits of the float representation with the sign bit cleared.
-static inline uint32_t abstop12(float x) noexcept {
+static inline uint32_t abstop12(float x) {
   return (as_uint32_bits(x) >> 20) & 0x7ff;
 }
 
@@ -44,7 +44,7 @@ static inline uint32_t abstop12(float x) noexcept {
 // polynomial P and store the results in SINP and COSP. N is the quadrant,
 // if odd the cosine and sine polynomials are swapped.
 static inline void sincosf_poly(double x, double x2, const sincos_t *p, int n,
-                                float *sinp, float *cosp) noexcept {
+                                float *sinp, float *cosp) {
   double x3, x4, x5, x6, s, c, c1, c2, s1;
 
   x4 = x2 * x2;
@@ -70,8 +70,7 @@ static inline void sincosf_poly(double x, double x2, const sincos_t *p, int n,
 
 // Return the sine of inputs X and X2 (X squared) using the polynomial P.
 // N is the quadrant, and if odd the cosine polynomial is used.
-static inline float sinf_poly(double x, double x2, const sincos_t *p,
-                              int n) noexcept {
+static inline float sinf_poly(double x, double x2, const sincos_t *p, int n) {
   double x3, x4, x6, x7, s, c, c1, c2, s1;
 
   if ((n & 1) == 0) {
@@ -99,8 +98,7 @@ static inline float sinf_poly(double x, double x2, const sincos_t *p,
 // The values for PI/2 and 2/PI are accessed via P. Since PI/2 as a double
 // is accurate to 55 bits and the worst-case cancellation happens at 6 * PI/4,
 // the result is accurate for |X| <= 120.0.
-static inline double reduce_fast(double x, const sincos_t *p,
-                                 int *np) noexcept {
+static inline double reduce_fast(double x, const sincos_t *p, int *np) {
   double r;
   // Use scaled float to int conversion with explicit rounding.
   // hpi_inv is prescaled by 2^24 so the quadrant ends up in bits 24..31.
@@ -118,7 +116,7 @@ static inline double reduce_fast(double x, const sincos_t *p,
 // multiply computes the exact 2.62-bit fixed-point modulo. Since the result
 // can have at most 29 leading zeros after the binary point, the double
 // precision result is accurate to 33 bits.
-static inline double reduce_large(uint32_t xi, int *np) noexcept {
+static inline double reduce_large(uint32_t xi, int *np) {
   const uint32_t *arr = &__inv_pio4[(xi >> 26) & 15];
   int shift = (xi >> 23) & 7;
   uint64_t n, res0, res1, res2;
diff --git a/libc/src/math/hypot.h b/libc/src/math/hypot.h
index 5778813123a59..6c901ee8f4c0c 100644
--- a/libc/src/math/hypot.h
+++ b/libc/src/math/hypot.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double hypot(double x, double y) noexcept;
+double hypot(double x, double y);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/hypotf.h b/libc/src/math/hypotf.h
index a64fa211477ab..084fd7f3ef814 100644
--- a/libc/src/math/hypotf.h
+++ b/libc/src/math/hypotf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float hypotf(float x, float y) noexcept;
+float hypotf(float x, float y);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/ilogb.h b/libc/src/math/ilogb.h
index 951dd44d30837..96672077865a9 100644
--- a/libc/src/math/ilogb.h
+++ b/libc/src/math/ilogb.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int ilogb(double x) noexcept;
+int ilogb(double x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/ilogbf.h b/libc/src/math/ilogbf.h
index d84c64f23b489..1afb76a107c1c 100644
--- a/libc/src/math/ilogbf.h
+++ b/libc/src/math/ilogbf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int ilogbf(float x) noexcept;
+int ilogbf(float x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/ilogbl.h b/libc/src/math/ilogbl.h
index 24d9c5cb0da10..4d1cc1995341b 100644
--- a/libc/src/math/ilogbl.h
+++ b/libc/src/math/ilogbl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int ilogbl(long double x) noexcept;
+int ilogbl(long double x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/ldexp.h b/libc/src/math/ldexp.h
index 6a3f486102037..74f9a600666fa 100644
--- a/libc/src/math/ldexp.h
+++ b/libc/src/math/ldexp.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double ldexp(double x, int exp) noexcept;
+double ldexp(double x, int exp);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/ldexpf.h b/libc/src/math/ldexpf.h
index 9a79f0cfda724..f30d60155f1fd 100644
--- a/libc/src/math/ldexpf.h
+++ b/libc/src/math/ldexpf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float ldexpf(float x, int exp) noexcept;
+float ldexpf(float x, int exp);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/ldexpl.h b/libc/src/math/ldexpl.h
index ac1c6664d45d9..bf8435b1a21d8 100644
--- a/libc/src/math/ldexpl.h
+++ b/libc/src/math/ldexpl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double ldexpl(long double x, int exp) noexcept;
+long double ldexpl(long double x, int exp);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/llrint.h b/libc/src/math/llrint.h
index 8a9c37022c22e..96bd7b8cc9e1c 100644
--- a/libc/src/math/llrint.h
+++ b/libc/src/math/llrint.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long long llrint(double x) noexcept;
+long long llrint(double x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/llrintf.h b/libc/src/math/llrintf.h
index eedd748c15c78..eecf380f5e94d 100644
--- a/libc/src/math/llrintf.h
+++ b/libc/src/math/llrintf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long long llrintf(float x) noexcept;
+long long llrintf(float x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/llrintl.h b/libc/src/math/llrintl.h
index e6e5d46edf6a4..94dfba7080aa9 100644
--- a/libc/src/math/llrintl.h
+++ b/libc/src/math/llrintl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long long llrintl(long double x) noexcept;
+long long llrintl(long double x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/llround.h b/libc/src/math/llround.h
index eae50a7d37dd7..5b2b7fc96df87 100644
--- a/libc/src/math/llround.h
+++ b/libc/src/math/llround.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long long llround(double x) noexcept;
+long long llround(double x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/llroundf.h b/libc/src/math/llroundf.h
index b65a8ddc0a285..65faad1e07a61 100644
--- a/libc/src/math/llroundf.h
+++ b/libc/src/math/llroundf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long long llroundf(float x) noexcept;
+long long llroundf(float x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/llroundl.h b/libc/src/math/llroundl.h
index 7cdf620746b24..f859485a730bd 100644
--- a/libc/src/math/llroundl.h
+++ b/libc/src/math/llroundl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long long llroundl(long double x) noexcept;
+long long llroundl(long double x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/logb.h b/libc/src/math/logb.h
index 6debaa8923632..b875dcd702bab 100644
--- a/libc/src/math/logb.h
+++ b/libc/src/math/logb.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double logb(double x) noexcept;
+double logb(double x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/logbf.h b/libc/src/math/logbf.h
index 7225b0252ad04..46dcd3c91d628 100644
--- a/libc/src/math/logbf.h
+++ b/libc/src/math/logbf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float logbf(float x) noexcept;
+float logbf(float x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/logbl.h b/libc/src/math/logbl.h
index 07d2aa6f83801..3630e52c92d29 100644
--- a/libc/src/math/logbl.h
+++ b/libc/src/math/logbl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double logbl(long double x) noexcept;
+long double logbl(long double x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/lrint.h b/libc/src/math/lrint.h
index 565cae847e3d4..62df79a1de230 100644
--- a/libc/src/math/lrint.h
+++ b/libc/src/math/lrint.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long lrint(double x) noexcept;
+long lrint(double x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/lrintf.h b/libc/src/math/lrintf.h
index 604f53d76e5d3..af5159437532b 100644
--- a/libc/src/math/lrintf.h
+++ b/libc/src/math/lrintf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long lrintf(float x) noexcept;
+long lrintf(float x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/lrintl.h b/libc/src/math/lrintl.h
index e16070f7c220e..812acecadafad 100644
--- a/libc/src/math/lrintl.h
+++ b/libc/src/math/lrintl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long lrintl(long double x) noexcept;
+long lrintl(long double x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/lround.h b/libc/src/math/lround.h
index 78631d51562e3..8c555e816c8ba 100644
--- a/libc/src/math/lround.h
+++ b/libc/src/math/lround.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long lround(double x) noexcept;
+long lround(double x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/lroundf.h b/libc/src/math/lroundf.h
index 19e31f1a156d1..3d318a7a2faba 100644
--- a/libc/src/math/lroundf.h
+++ b/libc/src/math/lroundf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long lroundf(float x) noexcept;
+long lroundf(float x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/lroundl.h b/libc/src/math/lroundl.h
index b6116e80925ee..a8b5aff0fcf38 100644
--- a/libc/src/math/lroundl.h
+++ b/libc/src/math/lroundl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long lroundl(long double x) noexcept;
+long lroundl(long double x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/modf.h b/libc/src/math/modf.h
index 2816e1c53916f..1dc732f6e89ab 100644
--- a/libc/src/math/modf.h
+++ b/libc/src/math/modf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double modf(double x, double *iptr) noexcept;
+double modf(double x, double *iptr);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/modff.h b/libc/src/math/modff.h
index 36d5849836d54..21457e0d2e81a 100644
--- a/libc/src/math/modff.h
+++ b/libc/src/math/modff.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float modff(float x, float *iptr) noexcept;
+float modff(float x, float *iptr);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/modfl.h b/libc/src/math/modfl.h
index 44206211bdf2e..ff89239c4bfde 100644
--- a/libc/src/math/modfl.h
+++ b/libc/src/math/modfl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double modfl(long double x, long double *iptr) noexcept;
+long double modfl(long double x, long double *iptr);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/nearbyint.h b/libc/src/math/nearbyint.h
index bde631c421549..957a06b979214 100644
--- a/libc/src/math/nearbyint.h
+++ b/libc/src/math/nearbyint.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double nearbyint(double x) noexcept;
+double nearbyint(double x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/nearbyintf.h b/libc/src/math/nearbyintf.h
index 9d1f42a905f1b..3793f6bc1b881 100644
--- a/libc/src/math/nearbyintf.h
+++ b/libc/src/math/nearbyintf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float nearbyintf(float x) noexcept;
+float nearbyintf(float x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/nearbyintl.h b/libc/src/math/nearbyintl.h
index 8b896002e178b..7029e86a52114 100644
--- a/libc/src/math/nearbyintl.h
+++ b/libc/src/math/nearbyintl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double nearbyintl(long double x) noexcept;
+long double nearbyintl(long double x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/nextafter.h b/libc/src/math/nextafter.h
index 89ff5cc4819b7..1f6d24de5f2e0 100644
--- a/libc/src/math/nextafter.h
+++ b/libc/src/math/nextafter.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double nextafter(double x, double y) noexcept;
+double nextafter(double x, double y);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/nextafterf.h b/libc/src/math/nextafterf.h
index 9ab90f26fa148..8afac0e5f6a03 100644
--- a/libc/src/math/nextafterf.h
+++ b/libc/src/math/nextafterf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float nextafterf(float x, float y) noexcept;
+float nextafterf(float x, float y);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/nextafterl.h b/libc/src/math/nextafterl.h
index 14f652e9904b3..912877867dc21 100644
--- a/libc/src/math/nextafterl.h
+++ b/libc/src/math/nextafterl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double nextafterl(long double x, long double y) noexcept;
+long double nextafterl(long double x, long double y);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/remainder.h b/libc/src/math/remainder.h
index 924fc15ec6abb..8a720fc23b6be 100644
--- a/libc/src/math/remainder.h
+++ b/libc/src/math/remainder.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double remainder(double x, double y) noexcept;
+double remainder(double x, double y);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/remainderf.h b/libc/src/math/remainderf.h
index f177e5c7e08ea..19a16d08a94d3 100644
--- a/libc/src/math/remainderf.h
+++ b/libc/src/math/remainderf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float remainderf(float x, float y) noexcept;
+float remainderf(float x, float y);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/remainderl.h b/libc/src/math/remainderl.h
index 2aeb09c2b56f8..f2837635ab77c 100644
--- a/libc/src/math/remainderl.h
+++ b/libc/src/math/remainderl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double remainderl(long double x, long double y) noexcept;
+long double remainderl(long double x, long double y);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/remquo.h b/libc/src/math/remquo.h
index c4a0b686aca28..cb753fee6ea0d 100644
--- a/libc/src/math/remquo.h
+++ b/libc/src/math/remquo.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double remquo(double x, double y, int *exp) noexcept;
+double remquo(double x, double y, int *exp);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/remquof.h b/libc/src/math/remquof.h
index 53ae441acb475..feb2e4f5e0dd5 100644
--- a/libc/src/math/remquof.h
+++ b/libc/src/math/remquof.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float remquof(float x, float y, int *exp) noexcept;
+float remquof(float x, float y, int *exp);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/remquol.h b/libc/src/math/remquol.h
index c50e3ec36faac..d1b0e20fcc865 100644
--- a/libc/src/math/remquol.h
+++ b/libc/src/math/remquol.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double remquol(long double x, long double y, int *exp) noexcept;
+long double remquol(long double x, long double y, int *exp);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/rint.h b/libc/src/math/rint.h
index f8b1a7612b527..e4910ad95a81c 100644
--- a/libc/src/math/rint.h
+++ b/libc/src/math/rint.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double rint(double x) noexcept;
+double rint(double x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/rintf.h b/libc/src/math/rintf.h
index 3de8f2703d4e7..0091ba3a8cd00 100644
--- a/libc/src/math/rintf.h
+++ b/libc/src/math/rintf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float rintf(float x) noexcept;
+float rintf(float x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/rintl.h b/libc/src/math/rintl.h
index 93d45b394ab5f..2bf095de76f88 100644
--- a/libc/src/math/rintl.h
+++ b/libc/src/math/rintl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double rintl(long double x) noexcept;
+long double rintl(long double x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/round.h b/libc/src/math/round.h
index b0378a577e2f2..bb09ea4a77c53 100644
--- a/libc/src/math/round.h
+++ b/libc/src/math/round.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double round(double x) noexcept;
+double round(double x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/roundf.h b/libc/src/math/roundf.h
index 8d39f4267ed61..6bab35adf781a 100644
--- a/libc/src/math/roundf.h
+++ b/libc/src/math/roundf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float roundf(float x) noexcept;
+float roundf(float x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/roundl.h b/libc/src/math/roundl.h
index 0b3aced3b2fa5..43fb63e231de4 100644
--- a/libc/src/math/roundl.h
+++ b/libc/src/math/roundl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double roundl(long double x) noexcept;
+long double roundl(long double x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/sin.h b/libc/src/math/sin.h
index 43dbe80fdb91c..f3919c46df603 100644
--- a/libc/src/math/sin.h
+++ b/libc/src/math/sin.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double sin(double x) noexcept;
+double sin(double x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/sincosf.h b/libc/src/math/sincosf.h
index 430f6f6417ae4..47ef983f4385f 100644
--- a/libc/src/math/sincosf.h
+++ b/libc/src/math/sincosf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-void sincosf(float x, float *sinx, float *cosx) noexcept;
+void sincosf(float x, float *sinx, float *cosx);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/sinf.h b/libc/src/math/sinf.h
index 8e6b4f3dc0c30..e63db04c51b5d 100644
--- a/libc/src/math/sinf.h
+++ b/libc/src/math/sinf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float sinf(float x) noexcept;
+float sinf(float x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/sqrt.h b/libc/src/math/sqrt.h
index 26dc527e8a5c0..2390e07b5dce5 100644
--- a/libc/src/math/sqrt.h
+++ b/libc/src/math/sqrt.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double sqrt(double x) noexcept;
+double sqrt(double x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/sqrtf.h b/libc/src/math/sqrtf.h
index 6ab9dbe208d7d..d1d06f3adfa8e 100644
--- a/libc/src/math/sqrtf.h
+++ b/libc/src/math/sqrtf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float sqrtf(float x) noexcept;
+float sqrtf(float x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/sqrtl.h b/libc/src/math/sqrtl.h
index a033849d77c85..5fbfa14507147 100644
--- a/libc/src/math/sqrtl.h
+++ b/libc/src/math/sqrtl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double sqrtl(long double x) noexcept;
+long double sqrtl(long double x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/tan.h b/libc/src/math/tan.h
index 6e733be6746ff..05366db52ff87 100644
--- a/libc/src/math/tan.h
+++ b/libc/src/math/tan.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double tan(double x) noexcept;
+double tan(double x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/trunc.h b/libc/src/math/trunc.h
index dba5d37d027f8..f7fed01f30d25 100644
--- a/libc/src/math/trunc.h
+++ b/libc/src/math/trunc.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-double trunc(double x) noexcept;
+double trunc(double x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/truncf.h b/libc/src/math/truncf.h
index 83f93b9dbf354..b4f1cd7ea72f6 100644
--- a/libc/src/math/truncf.h
+++ b/libc/src/math/truncf.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-float truncf(float x) noexcept;
+float truncf(float x);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/math/truncl.h b/libc/src/math/truncl.h
index 4b005c1e696ad..2a78ffaa3c5ef 100644
--- a/libc/src/math/truncl.h
+++ b/libc/src/math/truncl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long double truncl(long double x) noexcept;
+long double truncl(long double x);
 
 } // namespace __llvm_libc
 

From fa4c372ea8afdcf314cbdacf61f6e81461d76ffe Mon Sep 17 00:00:00 2001
From: Alfonso Gregory <83477269+gAlfonso-bit@users.noreply.github.com>
Date: Mon, 26 Jul 2021 13:29:02 -0400
Subject: [PATCH 09/17] Revert "Round 2"

This reverts commit b565df0ded41ce4667f10cfc0601cfeb6e212ced.
---
 libc/src/errno/__errno_location.h   |  2 +-
 libc/src/fenv/feclearexcept.h       |  2 +-
 libc/src/fenv/fegetenv.h            |  2 +-
 libc/src/fenv/fegetexceptflag.h     |  2 +-
 libc/src/fenv/fegetround.h          |  2 +-
 libc/src/fenv/feholdexcept.h        |  2 +-
 libc/src/fenv/feraiseexcept.h       |  2 +-
 libc/src/fenv/fesetenv.h            |  2 +-
 libc/src/fenv/fesetexceptflag.h     |  2 +-
 libc/src/fenv/fesetround.h          |  2 +-
 libc/src/fenv/fetestexcept.h        |  2 +-
 libc/src/fenv/feupdateenv.h         |  2 +-
 libc/utils/FPUtil/x86_64/FEnvImpl.h | 45 ++++++++++++++---------------
 libc/utils/FPUtil/x86_64/FMA.h      |  8 ++---
 14 files changed, 38 insertions(+), 39 deletions(-)

diff --git a/libc/src/errno/__errno_location.h b/libc/src/errno/__errno_location.h
index edc98535f63ef..20be3fcf812ae 100644
--- a/libc/src/errno/__errno_location.h
+++ b/libc/src/errno/__errno_location.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int *__errno_location() noexcept;
+int *__errno_location();
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/fenv/feclearexcept.h b/libc/src/fenv/feclearexcept.h
index 3266db3050ab7..fa771cee32a18 100644
--- a/libc/src/fenv/feclearexcept.h
+++ b/libc/src/fenv/feclearexcept.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int feclearexcept(int) noexcept;
+int feclearexcept(int);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/fenv/fegetenv.h b/libc/src/fenv/fegetenv.h
index 3849a9bbd88ee..e1001682a42bb 100644
--- a/libc/src/fenv/fegetenv.h
+++ b/libc/src/fenv/fegetenv.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-int fegetenv(fenv_t *) noexcept;
+int fegetenv(fenv_t *);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/fenv/fegetexceptflag.h b/libc/src/fenv/fegetexceptflag.h
index e173b4b722cf4..20913cb7a22f8 100644
--- a/libc/src/fenv/fegetexceptflag.h
+++ b/libc/src/fenv/fegetexceptflag.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-int fegetexceptflag(fexcept_t *, int excepts) noexcept;
+int fegetexceptflag(fexcept_t *, int excepts);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/fenv/fegetround.h b/libc/src/fenv/fegetround.h
index 7934dea2beaf5..1bc79cbf5a6c4 100644
--- a/libc/src/fenv/fegetround.h
+++ b/libc/src/fenv/fegetround.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int fegetround() noexcept;
+int fegetround();
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/fenv/feholdexcept.h b/libc/src/fenv/feholdexcept.h
index 5ac71e1d1c65b..cfb86b54ff49e 100644
--- a/libc/src/fenv/feholdexcept.h
+++ b/libc/src/fenv/feholdexcept.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-int feholdexcept(fenv_t *) noexcept;
+int feholdexcept(fenv_t *);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/fenv/feraiseexcept.h b/libc/src/fenv/feraiseexcept.h
index 446b255243eba..5c9eacf462d49 100644
--- a/libc/src/fenv/feraiseexcept.h
+++ b/libc/src/fenv/feraiseexcept.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int feraiseexcept(int) noexcept;
+int feraiseexcept(int);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/fenv/fesetenv.h b/libc/src/fenv/fesetenv.h
index fc6d612f193a2..316ecee41996e 100644
--- a/libc/src/fenv/fesetenv.h
+++ b/libc/src/fenv/fesetenv.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-int fesetenv(const fenv_t *) noexcept;
+int fesetenv(const fenv_t *);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/fenv/fesetexceptflag.h b/libc/src/fenv/fesetexceptflag.h
index 05dfe59a8e54b..0e6497abafaed 100644
--- a/libc/src/fenv/fesetexceptflag.h
+++ b/libc/src/fenv/fesetexceptflag.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-int fesetexceptflag(const fexcept_t *, int excepts) noexcept;
+int fesetexceptflag(const fexcept_t *, int excepts);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/fenv/fesetround.h b/libc/src/fenv/fesetround.h
index 6ad8c24f045d6..148a5eabcf3d5 100644
--- a/libc/src/fenv/fesetround.h
+++ b/libc/src/fenv/fesetround.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int fesetround(int) noexcept;
+int fesetround(int);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/fenv/fetestexcept.h b/libc/src/fenv/fetestexcept.h
index f67796343ae63..fb3e4045dd6b0 100644
--- a/libc/src/fenv/fetestexcept.h
+++ b/libc/src/fenv/fetestexcept.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int fetestexcept(int) noexcept;
+int fetestexcept(int);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/fenv/feupdateenv.h b/libc/src/fenv/feupdateenv.h
index 9e2d6cec67e69..1599c01ebddff 100644
--- a/libc/src/fenv/feupdateenv.h
+++ b/libc/src/fenv/feupdateenv.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-int feupdateenv(const fenv_t *) noexcept;
+int feupdateenv(const fenv_t *);
 
 } // namespace __llvm_libc
 
diff --git a/libc/utils/FPUtil/x86_64/FEnvImpl.h b/libc/utils/FPUtil/x86_64/FEnvImpl.h
index f628d3211bb4b..fae74bb5da9bc 100644
--- a/libc/utils/FPUtil/x86_64/FEnvImpl.h
+++ b/libc/utils/FPUtil/x86_64/FEnvImpl.h
@@ -61,7 +61,7 @@ static constexpr uint16_t MXCSRExceptionContolBitPoistion = 7;
 
 // Exception flags are individual bits in the corresponding registers.
 // So, we just OR the bit values to get the full set of exceptions.
-static constexpr uint16_t getStatusValueForExcept(int excepts) {
+static inline uint16_t getStatusValueForExcept(int excepts) {
   // We will make use of the fact that exception control bits are single
   // bit flags in the control registers.
   return (excepts & FE_INVALID ? ExceptionFlags::Invalid : 0) |
@@ -74,7 +74,7 @@ static constexpr uint16_t getStatusValueForExcept(int excepts) {
          (excepts & FE_INEXACT ? ExceptionFlags::Inexact : 0);
 }
 
-static constexpr int exceptionStatusToMacro(uint16_t status) {
+static inline int exceptionStatusToMacro(uint16_t status) {
   return (status & ExceptionFlags::Invalid ? FE_INVALID : 0) |
 #ifdef __FE_DENORM
          (status & ExceptionFlags::Denormal ? __FE_DENORM : 0) |
@@ -107,54 +107,53 @@ static_assert(
     sizeof(fenv_t) == sizeof(FPState),
     "Internal floating point state does not match the public fenv_t type.");
 
-static inline uint16_t getX87ControlWord() noexcept {
+static inline uint16_t getX87ControlWord() {
   uint16_t w;
   __asm__ __volatile__("fnstcw %0" : "=m"(w)::);
   SANITIZER_MEMORY_INITIALIZED(&w, sizeof(w));
   return w;
 }
 
-static inline void writeX87ControlWord(uint16_t w) noexcept {
+static inline void writeX87ControlWord(uint16_t w) {
   __asm__ __volatile__("fldcw %0" : : "m"(w) :);
 }
 
-static inline uint16_t getX87StatusWord() noexcept {
+static inline uint16_t getX87StatusWord() {
   uint16_t w;
   __asm__ __volatile__("fnstsw %0" : "=m"(w)::);
   SANITIZER_MEMORY_INITIALIZED(&w, sizeof(w));
   return w;
 }
 
-static inline void clearX87Exceptions() noexcept {
+static inline void clearX87Exceptions() {
   __asm__ __volatile__("fnclex" : : :);
 }
 
-static inline uint32_t getMXCSR() noexcept {
+static inline uint32_t getMXCSR() {
   uint32_t w;
   __asm__ __volatile__("stmxcsr %0" : "=m"(w)::);
   SANITIZER_MEMORY_INITIALIZED(&w, sizeof(w));
   return w;
 }
 
-static inline void writeMXCSR(uint32_t w) noexcept {
+static inline void writeMXCSR(uint32_t w) {
   __asm__ __volatile__("ldmxcsr %0" : : "m"(w) :);
 }
 
-static inline void getX87StateDescriptor(X87StateDescriptor &s) noexcept {
+static inline void getX87StateDescriptor(X87StateDescriptor &s) {
   __asm__ __volatile__("fnstenv %0" : "=m"(s));
   SANITIZER_MEMORY_INITIALIZED(&s, sizeof(s));
 }
 
-static inline void
-writeX87StateDescriptor(const X87StateDescriptor &s) noexcept {
+static inline void writeX87StateDescriptor(const X87StateDescriptor &s) {
   __asm__ __volatile__("fldenv %0" : : "m"(s) :);
 }
 
-static inline void fwait() noexcept { __asm__ __volatile__("fwait"); }
+static inline void fwait() { __asm__ __volatile__("fwait"); }
 
 } // namespace internal
 
-static inline int enableExcept(int excepts) noexcept {
+static inline int enableExcept(int excepts) {
   // In the x87 control word and in MXCSR, an exception is blocked
   // if the corresponding bit is set. That is the reason for all the
   // bit-flip operations below as we need to turn the bits to zero
@@ -181,7 +180,7 @@ static inline int enableExcept(int excepts) noexcept {
   return internal::exceptionStatusToMacro(oldExcepts);
 }
 
-static inline int disableExcept(int excepts) noexcept {
+static inline int disableExcept(int excepts) {
   // In the x87 control word and in MXCSR, an exception is blocked
   // if the corresponding bit is set.
 
@@ -201,7 +200,7 @@ static inline int disableExcept(int excepts) noexcept {
   return internal::exceptionStatusToMacro(oldExcepts);
 }
 
-static inline int clearExcept(int excepts) noexcept {
+static inline int clearExcept(int excepts) {
   internal::X87StateDescriptor state;
   internal::getX87StateDescriptor(state);
   state.StatusWord &= ~internal::getStatusValueForExcept(excepts);
@@ -213,7 +212,7 @@ static inline int clearExcept(int excepts) noexcept {
   return 0;
 }
 
-static inline int testExcept(int excepts) noexcept {
+static inline int testExcept(int excepts) {
   uint16_t statusValue = internal::getStatusValueForExcept(excepts);
   // Check both x87 status word and MXCSR.
   return internal::exceptionStatusToMacro(
@@ -222,7 +221,7 @@ static inline int testExcept(int excepts) noexcept {
 }
 
 // Sets the exception flags but does not trigger the exception handler.
-static inline int setExcept(int excepts) noexcept {
+static inline int setExcept(int excepts) {
   uint16_t statusValue = internal::getStatusValueForExcept(excepts);
   internal::X87StateDescriptor state;
   internal::getX87StateDescriptor(state);
@@ -236,7 +235,7 @@ static inline int setExcept(int excepts) noexcept {
   return 0;
 }
 
-static inline int raiseExcept(int excepts) noexcept {
+static inline int raiseExcept(int excepts) {
   uint16_t statusValue = internal::getStatusValueForExcept(excepts);
 
   // We set the status flag for exception one at a time and call the
@@ -252,7 +251,7 @@ static inline int raiseExcept(int excepts) noexcept {
   // ensure that the writes by the exception handler are maintained
   // when raising the next exception.
 
-  auto raiseHelper = [](uint16_t singleExceptFlag) {
+  auto raiseHelper = [](uint16_t  singleExceptFlag) {
     internal::X87StateDescriptor state;
     internal::getX87StateDescriptor(state);
     state.StatusWord |= singleExceptFlag;
@@ -284,7 +283,7 @@ static inline int raiseExcept(int excepts) noexcept {
   return 0;
 }
 
-static inline int getRound() noexcept {
+static inline int getRound() {
   uint16_t bitValue =
       (internal::getMXCSR() >> internal::MXCSRRoundingControlBitPosition) & 0x3;
   switch (bitValue) {
@@ -301,7 +300,7 @@ static inline int getRound() noexcept {
   }
 }
 
-static inline int setRound(int mode) noexcept {
+static inline int setRound(int mode) {
   uint16_t bitValue;
   switch (mode) {
   case FE_TONEAREST:
@@ -340,14 +339,14 @@ static inline int setRound(int mode) noexcept {
 }
 
 #if !(defined(_WIN32))
-static inline int getEnv(fenv_t *envp) noexcept {
+static inline int getEnv(fenv_t *envp) {
   internal::FPState *state = reinterpret_cast<internal::FPState *>(envp);
   internal::getX87StateDescriptor(state->X87Status);
   state->MXCSR = internal::getMXCSR();
   return 0;
 }
 
-static inline int setEnv(const fenv_t *envp) noexcept {
+static inline int setEnv(const fenv_t *envp) {
   const internal::FPState *state =
       reinterpret_cast<const internal::FPState *>(envp);
   internal::writeX87StateDescriptor(state->X87Status);
diff --git a/libc/utils/FPUtil/x86_64/FMA.h b/libc/utils/FPUtil/x86_64/FMA.h
index 0f38e837cbca5..e1bc806e4ac8b 100644
--- a/libc/utils/FPUtil/x86_64/FMA.h
+++ b/libc/utils/FPUtil/x86_64/FMA.h
@@ -15,8 +15,8 @@ namespace __llvm_libc {
 namespace fputil {
 
 template <typename T>
-static inline cpp::EnableIfType<cpp::IsSame<T, float>::Value, T>
-fma(T x, T y, T z) noexcept {
+static inline cpp::EnableIfType<cpp::IsSame<T, float>::Value, T> fma(T x, T y,
+                                                                     T z) {
   float result = x;
   __asm__ __volatile__("vfmadd213ss %x2, %x1, %x0"
                        : "+x"(result)
@@ -25,8 +25,8 @@ fma(T x, T y, T z) noexcept {
 }
 
 template <typename T>
-static inline cpp::EnableIfType<cpp::IsSame<T, double>::Value, T>
-fma(T x, T y, T z) noexcept {
+static inline cpp::EnableIfType<cpp::IsSame<T, double>::Value, T> fma(T x, T y,
+                                                                      T z) {
   double result = x;
   __asm__ __volatile__("vfmadd213sd %x2, %x1, %x0"
                        : "+x"(result)

From a112a6ecb6b39d3723492e6806901cd6a1e57972 Mon Sep 17 00:00:00 2001
From: Alfonso Gregory <83477269+gAlfonso-bit@users.noreply.github.com>
Date: Mon, 26 Jul 2021 13:29:47 -0400
Subject: [PATCH 10/17] OK

---
 libc/utils/FPUtil/x86_64/FEnvImpl.h | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/libc/utils/FPUtil/x86_64/FEnvImpl.h b/libc/utils/FPUtil/x86_64/FEnvImpl.h
index fae74bb5da9bc..e235d83fb2354 100644
--- a/libc/utils/FPUtil/x86_64/FEnvImpl.h
+++ b/libc/utils/FPUtil/x86_64/FEnvImpl.h
@@ -61,7 +61,7 @@ static constexpr uint16_t MXCSRExceptionContolBitPoistion = 7;
 
 // Exception flags are individual bits in the corresponding registers.
 // So, we just OR the bit values to get the full set of exceptions.
-static inline uint16_t getStatusValueForExcept(int excepts) {
+static constexpr uint16_t getStatusValueForExcept(int excepts) {
   // We will make use of the fact that exception control bits are single
   // bit flags in the control registers.
   return (excepts & FE_INVALID ? ExceptionFlags::Invalid : 0) |
@@ -74,7 +74,7 @@ static inline uint16_t getStatusValueForExcept(int excepts) {
          (excepts & FE_INEXACT ? ExceptionFlags::Inexact : 0);
 }
 
-static inline int exceptionStatusToMacro(uint16_t status) {
+static constexpr int exceptionStatusToMacro(uint16_t status) {
   return (status & ExceptionFlags::Invalid ? FE_INVALID : 0) |
 #ifdef __FE_DENORM
          (status & ExceptionFlags::Denormal ? __FE_DENORM : 0) |
@@ -251,7 +251,7 @@ static inline int raiseExcept(int excepts) {
   // ensure that the writes by the exception handler are maintained
   // when raising the next exception.
 
-  auto raiseHelper = [](uint16_t  singleExceptFlag) {
+  auto raiseHelper = [](uint16_t singleExceptFlag) {
     internal::X87StateDescriptor state;
     internal::getX87StateDescriptor(state);
     state.StatusWord |= singleExceptFlag;

From 1e4eba0170602cbcd761eb8b1f0f5ade54d0f6c7 Mon Sep 17 00:00:00 2001
From: Alfonso Gregory <83477269+gAlfonso-bit@users.noreply.github.com>
Date: Mon, 26 Jul 2021 13:30:30 -0400
Subject: [PATCH 11/17] Revert "stdlib and signal"

This reverts commit 857d6ccbc48c5b549b828c7cd15c963517acd188.
---
 libc/config/linux/x86_64/syscall.h.inc | 159 ++++++++++++-------------
 libc/src/signal/linux/sigaction.cpp    |   2 +-
 libc/src/signal/linux/sigaddset.cpp    |   4 +-
 libc/src/signal/linux/sigdelset.cpp    |   4 +-
 libc/src/signal/linux/sigemptyset.cpp  |   2 +-
 libc/src/signal/linux/sigfillset.cpp   |   2 +-
 libc/src/signal/linux/signal.h         |   4 +-
 libc/src/signal/raise.h                |   2 +-
 libc/src/signal/sigaction.h            |   2 +-
 libc/src/signal/sigaddset.h            |   2 +-
 libc/src/signal/sigdelset.h            |   2 +-
 libc/src/signal/sigemptyset.h          |   2 +-
 libc/src/signal/sigfillset.h           |   2 +-
 libc/src/signal/signal.h               |   2 +-
 libc/src/signal/sigprocmask.h          |   2 +-
 libc/src/stdio/FILE.h                  |   2 +-
 libc/src/stdio/fwrite.cpp              |   4 +-
 libc/src/stdio/fwrite.h                |   2 +-
 libc/src/stdlib/abort.cpp              |   2 +-
 libc/src/stdlib/abs.h                  |   2 +-
 libc/src/stdlib/labs.h                 |   2 +-
 libc/src/stdlib/linux/_Exit.cpp        |   2 +-
 libc/src/stdlib/llabs.h                |   2 +-
 23 files changed, 105 insertions(+), 106 deletions(-)

diff --git a/libc/config/linux/x86_64/syscall.h.inc b/libc/config/linux/x86_64/syscall.h.inc
index de34d8ed21625..ee3b5e5bfc0d7 100644
--- a/libc/config/linux/x86_64/syscall.h.inc
+++ b/libc/config/linux/x86_64/syscall.h.inc
@@ -14,93 +14,92 @@
 
 namespace __llvm_libc {
 
-  __attribute__((always_inline)) inline long syscall(long __number) noexcept {
-    long retcode;
-    LIBC_INLINE_ASM("syscall"
-                    : "=a"(retcode)
-                    : "a"(__number)
-                    : SYSCALL_CLOBBER_LIST);
-    return retcode;
-  }
+__attribute__((always_inline)) inline long syscall(long __number) {
+  long retcode;
+  LIBC_INLINE_ASM("syscall"
+                  : "=a"(retcode)
+                  : "a"(__number)
+                  : SYSCALL_CLOBBER_LIST);
+  return retcode;
+}
 
-  __attribute__((always_inline)) inline long syscall(long __number,
-                                                     long __arg1) noexcept {
-    long retcode;
-    LIBC_INLINE_ASM("syscall"
-                    : "=a"(retcode)
-                    : "a"(__number), "D"(__arg1)
-                    : SYSCALL_CLOBBER_LIST);
-    return retcode;
-  }
+__attribute__((always_inline)) inline long syscall(long __number, long __arg1) {
+  long retcode;
+  LIBC_INLINE_ASM("syscall"
+                  : "=a"(retcode)
+                  : "a"(__number), "D"(__arg1)
+                  : SYSCALL_CLOBBER_LIST);
+  return retcode;
+}
 
-  __attribute__((always_inline)) inline long syscall(long __number, long __arg1,
-                                                     long __arg2) noexcept {
-    long retcode;
-    LIBC_INLINE_ASM("syscall"
-                    : "=a"(retcode)
-                    : "a"(__number), "D"(__arg1), "S"(__arg2)
-                    : SYSCALL_CLOBBER_LIST);
-    return retcode;
-  }
+__attribute__((always_inline)) inline long syscall(long __number, long __arg1,
+                                                   long __arg2) {
+  long retcode;
+  LIBC_INLINE_ASM("syscall"
+                  : "=a"(retcode)
+                  : "a"(__number), "D"(__arg1), "S"(__arg2)
+                  : SYSCALL_CLOBBER_LIST);
+  return retcode;
+}
 
-  __attribute__((always_inline)) inline long syscall(
-      long __number, long __arg1, long __arg2, long __arg3) noexcept {
-    long retcode;
-    LIBC_INLINE_ASM("syscall"
-                    : "=a"(retcode)
-                    : "a"(__number), "D"(__arg1), "S"(__arg2), "d"(__arg3)
-                    : SYSCALL_CLOBBER_LIST);
-    return retcode;
-  }
+__attribute__((always_inline)) inline long syscall(long __number, long __arg1,
+                                                   long __arg2, long __arg3) {
+  long retcode;
+  LIBC_INLINE_ASM("syscall"
+                  : "=a"(retcode)
+                  : "a"(__number), "D"(__arg1), "S"(__arg2), "d"(__arg3)
+                  : SYSCALL_CLOBBER_LIST);
+  return retcode;
+}
 
-  __attribute__((always_inline)) inline long syscall(long __number, long __arg1,
-                                                     long __arg2, long __arg3,
-                                                     long __arg4) noexcept {
-    long retcode;
-    register long r10 __asm__("r10") = __arg4;
-    LIBC_INLINE_ASM("syscall"
-                    : "=a"(retcode)
-                    : "a"(__number), "D"(__arg1), "S"(__arg2), "d"(__arg3),
-                      "r"(r10)
-                    : SYSCALL_CLOBBER_LIST);
-    return retcode;
-  }
+__attribute__((always_inline)) inline long
+syscall(long __number, long __arg1, long __arg2, long __arg3, long __arg4) {
+  long retcode;
+  register long r10 __asm__("r10") = __arg4;
+  LIBC_INLINE_ASM("syscall"
+                  : "=a"(retcode)
+                  : "a"(__number), "D"(__arg1), "S"(__arg2), "d"(__arg3),
+                    "r"(r10)
+                  : SYSCALL_CLOBBER_LIST);
+  return retcode;
+}
 
-  __attribute__((always_inline)) inline long syscall(
-      long __number, long __arg1, long __arg2, long __arg3, long __arg4,
-      long __arg5) noexcept {
-    long retcode;
-    register long r10 __asm__("r10") = __arg4;
-    register long r8 __asm__("r8") = __arg5;
-    LIBC_INLINE_ASM("syscall"
-                    : "=a"(retcode)
-                    : "a"(__number), "D"(__arg1), "S"(__arg2), "d"(__arg3),
-                      "r"(r10), "r"(r8)
-                    : SYSCALL_CLOBBER_LIST);
-    return retcode;
-  }
+__attribute__((always_inline)) inline long syscall(long __number, long __arg1,
+                                                   long __arg2, long __arg3,
+                                                   long __arg4, long __arg5) {
+  long retcode;
+  register long r10 __asm__("r10") = __arg4;
+  register long r8 __asm__("r8") = __arg5;
+  LIBC_INLINE_ASM("syscall"
+                  : "=a"(retcode)
+                  : "a"(__number), "D"(__arg1), "S"(__arg2), "d"(__arg3),
+                    "r"(r10), "r"(r8)
+                  : SYSCALL_CLOBBER_LIST);
+  return retcode;
+}
 
-  __attribute__((always_inline)) inline long syscall(
-      long __number, long __arg1, long __arg2, long __arg3, long __arg4,
-      long __arg5, long __arg6) noexcept {
-    long retcode;
-    register long r10 __asm__("r10") = __arg4;
-    register long r8 __asm__("r8") = __arg5;
-    register long r9 __asm__("r9") = __arg6;
-    LIBC_INLINE_ASM("syscall"
-                    : "=a"(retcode)
-                    : "a"(__number), "D"(__arg1), "S"(__arg2), "d"(__arg3),
-                      "r"(r10), "r"(r8), "r"(r9)
-                    : SYSCALL_CLOBBER_LIST);
-    return retcode;
-  }
+__attribute__((always_inline)) inline long syscall(long __number, long __arg1,
+                                                   long __arg2, long __arg3,
+                                                   long __arg4, long __arg5,
+                                                   long __arg6) {
+  long retcode;
+  register long r10 __asm__("r10") = __arg4;
+  register long r8 __asm__("r8") = __arg5;
+  register long r9 __asm__("r9") = __arg6;
+  LIBC_INLINE_ASM("syscall"
+                  : "=a"(retcode)
+                  : "a"(__number), "D"(__arg1), "S"(__arg2), "d"(__arg3),
+                    "r"(r10), "r"(r8), "r"(r9)
+                  : SYSCALL_CLOBBER_LIST);
+  return retcode;
+}
+
+template <typename... Ts>
+__attribute__((always_inline)) inline long syscall(long __number, Ts... ts) {
+  static_assert(sizeof...(Ts) <= 6, "Too many arguments for syscall");
+  return syscall(__number, (long)ts...);
+}
 
-  template <typename... Ts>
-  __attribute__((always_inline)) inline long syscall(long __number,
-                                                     Ts... ts) noexcept {
-    static_assert(sizeof...(Ts) <= 6, "Too many arguments for syscall");
-    return syscall(__number, static_cast<long>(ts...));
-  }
 
 #undef SYSCALL_CLOBBER_LIST
 
diff --git a/libc/src/signal/linux/sigaction.cpp b/libc/src/signal/linux/sigaction.cpp
index 8ecda77d6f8d3..602fc71bf390c 100644
--- a/libc/src/signal/linux/sigaction.cpp
+++ b/libc/src/signal/linux/sigaction.cpp
@@ -21,7 +21,7 @@ namespace __llvm_libc {
 extern "C" void __restore_rt();
 
 template <typename T, typename V>
-static void copySigaction(T &dest, const V &source) noexcept {
+static void copySigaction(T &dest, const V &source) {
   dest.sa_handler = source.sa_handler;
   dest.sa_mask = source.sa_mask;
   dest.sa_flags = source.sa_flags;
diff --git a/libc/src/signal/linux/sigaddset.cpp b/libc/src/signal/linux/sigaddset.cpp
index a7732645dea9a..bc51ef67e0b3a 100644
--- a/libc/src/signal/linux/sigaddset.cpp
+++ b/libc/src/signal/linux/sigaddset.cpp
@@ -15,8 +15,8 @@
 
 namespace __llvm_libc {
 
-LLVM_LIBC_FUNCTION(int, sigaddset, (sigset_t * set, int signum)) noexcept {
-  if (!set || static_cast<unsigned>(signum - 1) >= (8 * sizeof(sigset_t))) {
+LLVM_LIBC_FUNCTION(int, sigaddset, (sigset_t * set, int signum)) {
+  if (!set || (unsigned)(signum - 1) >= (8 * sizeof(sigset_t))) {
     llvmlibc_errno = EINVAL;
     return -1;
   }
diff --git a/libc/src/signal/linux/sigdelset.cpp b/libc/src/signal/linux/sigdelset.cpp
index 60b84a3f9865f..f870f71560074 100644
--- a/libc/src/signal/linux/sigdelset.cpp
+++ b/libc/src/signal/linux/sigdelset.cpp
@@ -15,8 +15,8 @@
 
 namespace __llvm_libc {
 
-LLVM_LIBC_FUNCTION(int, sigdelset, (sigset_t * set, int signum)) noexcept {
-  if (!set || static_cast<unsigned>(signum - 1) >= (8 * sizeof(sigset_t))) {
+LLVM_LIBC_FUNCTION(int, sigdelset, (sigset_t * set, int signum)) {
+  if (!set || (unsigned)(signum - 1) >= (8 * sizeof(sigset_t))) {
     llvmlibc_errno = EINVAL;
     return -1;
   }
diff --git a/libc/src/signal/linux/sigemptyset.cpp b/libc/src/signal/linux/sigemptyset.cpp
index 542e2f8635b3f..bce5fea7c963b 100644
--- a/libc/src/signal/linux/sigemptyset.cpp
+++ b/libc/src/signal/linux/sigemptyset.cpp
@@ -15,7 +15,7 @@
 
 namespace __llvm_libc {
 
-LLVM_LIBC_FUNCTION(int, sigemptyset, (sigset_t * set)) noexcept {
+LLVM_LIBC_FUNCTION(int, sigemptyset, (sigset_t * set)) {
   if (!set) {
     llvmlibc_errno = EINVAL;
     return -1;
diff --git a/libc/src/signal/linux/sigfillset.cpp b/libc/src/signal/linux/sigfillset.cpp
index 1377263c7b17b..1b908f1992640 100644
--- a/libc/src/signal/linux/sigfillset.cpp
+++ b/libc/src/signal/linux/sigfillset.cpp
@@ -15,7 +15,7 @@
 
 namespace __llvm_libc {
 
-LLVM_LIBC_FUNCTION(int, sigfillset, (sigset_t * set)) noexcept {
+LLVM_LIBC_FUNCTION(int, sigfillset, (sigset_t * set)) {
   if (!set) {
     llvmlibc_errno = EINVAL;
     return -1;
diff --git a/libc/src/signal/linux/signal.h b/libc/src/signal/linux/signal.h
index d9687952713bd..89b471b4079e4 100644
--- a/libc/src/signal/linux/signal.h
+++ b/libc/src/signal/linux/signal.h
@@ -35,7 +35,7 @@ struct Sigset {
 
 constexpr static Sigset all = Sigset::fullset();
 
-static inline int block_all_signals(Sigset &set) noexcept {
+static inline int block_all_signals(Sigset &set) {
   sigset_t nativeSigset = all;
   sigset_t oldSet = set;
   int ret = __llvm_libc::syscall(SYS_rt_sigprocmask, SIG_BLOCK, &nativeSigset,
@@ -44,7 +44,7 @@ static inline int block_all_signals(Sigset &set) noexcept {
   return ret;
 }
 
-static inline int restore_signals(const Sigset &set) noexcept {
+static inline int restore_signals(const Sigset &set) {
   sigset_t nativeSigset = set;
   return __llvm_libc::syscall(SYS_rt_sigprocmask, SIG_SETMASK, &nativeSigset,
                               nullptr, sizeof(sigset_t));
diff --git a/libc/src/signal/raise.h b/libc/src/signal/raise.h
index d477fca998090..00fd4c8fbda99 100644
--- a/libc/src/signal/raise.h
+++ b/libc/src/signal/raise.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-int raise(int sig) noexcept;
+int raise(int sig);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/signal/sigaction.h b/libc/src/signal/sigaction.h
index c72902cd79946..105ab1b250cc6 100644
--- a/libc/src/signal/sigaction.h
+++ b/libc/src/signal/sigaction.h
@@ -15,7 +15,7 @@
 namespace __llvm_libc {
 
 int sigaction(int signal, const struct __sigaction *__restrict libc_new,
-              struct __sigaction *__restrict libc_old) noexcept;
+              struct __sigaction *__restrict libc_old);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/signal/sigaddset.h b/libc/src/signal/sigaddset.h
index 7eb76ccc92439..40cec9f00c647 100644
--- a/libc/src/signal/sigaddset.h
+++ b/libc/src/signal/sigaddset.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-int sigaddset(sigset_t *set, int signum) noexcept;
+int sigaddset(sigset_t *set, int signum);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/signal/sigdelset.h b/libc/src/signal/sigdelset.h
index c055d34010f35..a005d9c0aa138 100644
--- a/libc/src/signal/sigdelset.h
+++ b/libc/src/signal/sigdelset.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-int sigdelset(sigset_t *set, int signum) noexcept;
+int sigdelset(sigset_t *set, int signum);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/signal/sigemptyset.h b/libc/src/signal/sigemptyset.h
index 7d418a06ade7e..0651c7302f992 100644
--- a/libc/src/signal/sigemptyset.h
+++ b/libc/src/signal/sigemptyset.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-int sigemptyset(sigset_t *set) noexcept;
+int sigemptyset(sigset_t *set);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/signal/sigfillset.h b/libc/src/signal/sigfillset.h
index af60fb86694eb..ed3612ce4ed5a 100644
--- a/libc/src/signal/sigfillset.h
+++ b/libc/src/signal/sigfillset.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-int sigfillset(sigset_t *set) noexcept;
+int sigfillset(sigset_t *set);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/signal/signal.h b/libc/src/signal/signal.h
index bd10c6d61de4f..4315497e2cf8c 100644
--- a/libc/src/signal/signal.h
+++ b/libc/src/signal/signal.h
@@ -15,7 +15,7 @@ namespace __llvm_libc {
 
 using sighandler_t = __sighandler_t;
 
-sighandler_t signal(int signum, sighandler_t handler) noexcept;
+sighandler_t signal(int signum, sighandler_t handler);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/signal/sigprocmask.h b/libc/src/signal/sigprocmask.h
index 41a79f6a5706c..353c0c84b38a1 100644
--- a/libc/src/signal/sigprocmask.h
+++ b/libc/src/signal/sigprocmask.h
@@ -14,7 +14,7 @@
 namespace __llvm_libc {
 
 int sigprocmask(int how, const sigset_t *__restrict set,
-                sigset_t *__restrict oldset) noexcept;
+                sigset_t *__restrict oldset);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/stdio/FILE.h b/libc/src/stdio/FILE.h
index 7051838af4945..54bc9b2c87311 100644
--- a/libc/src/stdio/FILE.h
+++ b/libc/src/stdio/FILE.h
@@ -19,7 +19,7 @@ struct FILE {
 
   using write_function_t = size_t(FILE *, const char *, size_t);
 
-  write_function_t *write noexcept;
+  write_function_t *write;
 };
 
 } // namespace __llvm_libc
diff --git a/libc/src/stdio/fwrite.cpp b/libc/src/stdio/fwrite.cpp
index d54aad2ec0934..80cf50ca376e4 100644
--- a/libc/src/stdio/fwrite.cpp
+++ b/libc/src/stdio/fwrite.cpp
@@ -14,13 +14,13 @@
 namespace __llvm_libc {
 
 size_t fwrite_unlocked(const void *__restrict ptr, size_t size, size_t nmeb,
-                       __llvm_libc::FILE *__restrict stream) noexcept {
+                       __llvm_libc::FILE *__restrict stream) {
   return stream->write(stream, reinterpret_cast<const char *>(ptr),
                        size * nmeb);
 }
 
 size_t fwrite(const void *__restrict ptr, size_t size, size_t nmeb,
-              __llvm_libc::FILE *__restrict stream) noexcept {
+              __llvm_libc::FILE *__restrict stream) {
   __llvm_libc::mtx_lock(&stream->lock);
   size_t written = fwrite_unlocked(ptr, size, nmeb, stream);
   __llvm_libc::mtx_unlock(&stream->lock);
diff --git a/libc/src/stdio/fwrite.h b/libc/src/stdio/fwrite.h
index 7dd03da033434..8a71ca105bb08 100644
--- a/libc/src/stdio/fwrite.h
+++ b/libc/src/stdio/fwrite.h
@@ -15,7 +15,7 @@
 namespace __llvm_libc {
 
 size_t fwrite(const void *__restrict ptr, size_t size, size_t nmeb,
-              __llvm_libc::FILE *__restrict stream) noexcept;
+              __llvm_libc::FILE *__restrict stream);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/stdlib/abort.cpp b/libc/src/stdlib/abort.cpp
index 0dfab6ebbeded..1da81611273de 100644
--- a/libc/src/stdlib/abort.cpp
+++ b/libc/src/stdlib/abort.cpp
@@ -14,7 +14,7 @@
 
 namespace __llvm_libc {
 
-[[noreturn]] LLVM_LIBC_FUNCTION(void, abort, ()) {
+LLVM_LIBC_FUNCTION(void, abort, ()) {
   // TODO: When sigprocmask and sigaction land:
   // Unblock SIGABRT, raise it, if it was ignored or the handler returned,
   // change its action to SIG_DFL, raise it again.
diff --git a/libc/src/stdlib/abs.h b/libc/src/stdlib/abs.h
index d7fc1fd91f522..42ef7f885ed65 100644
--- a/libc/src/stdlib/abs.h
+++ b/libc/src/stdlib/abs.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int abs(int n) noexcept;
+int abs(int n);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/stdlib/labs.h b/libc/src/stdlib/labs.h
index 5d52ca9701de6..0f0ea99dc22a7 100644
--- a/libc/src/stdlib/labs.h
+++ b/libc/src/stdlib/labs.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long labs(long n) noexcept;
+long labs(long n);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/stdlib/linux/_Exit.cpp b/libc/src/stdlib/linux/_Exit.cpp
index 89b223b35a6ba..7fdd60ffe9bc6 100644
--- a/libc/src/stdlib/linux/_Exit.cpp
+++ b/libc/src/stdlib/linux/_Exit.cpp
@@ -14,7 +14,7 @@
 
 namespace __llvm_libc {
 
-[[noreturn]] LLVM_LIBC_FUNCTION(void, _Exit, (int status)) {
+LLVM_LIBC_FUNCTION(void, _Exit, (int status)) {
   for (;;) {
     __llvm_libc::syscall(SYS_exit_group, status);
     __llvm_libc::syscall(SYS_exit, status);
diff --git a/libc/src/stdlib/llabs.h b/libc/src/stdlib/llabs.h
index fcbe64ca45682..f173431a14f15 100644
--- a/libc/src/stdlib/llabs.h
+++ b/libc/src/stdlib/llabs.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-long long llabs(long long n) noexcept;
+long long llabs(long long n);
 
 } // namespace __llvm_libc
 

From a6bc6686b3cad065b59ccd4a604076e18200d804 Mon Sep 17 00:00:00 2001
From: Alfonso Gregory <83477269+gAlfonso-bit@users.noreply.github.com>
Date: Mon, 26 Jul 2021 13:31:31 -0400
Subject: [PATCH 12/17] Revert "Done"

This reverts commit 690324b85eb3af5f5c114433b6a69a54e2fa7523.
---
 libc/src/sys/mman/mmap.h                      |  3 +-
 libc/src/sys/mman/munmap.h                    |  2 +-
 libc/src/threads/call_once.h                  |  2 +-
 libc/src/threads/linux/thrd_create.cpp        |  2 +-
 .../linux/x86_64/thread_start_args.h.in       |  2 +-
 libc/src/threads/mtx_init.h                   |  2 +-
 libc/src/threads/mtx_lock.h                   |  2 +-
 libc/src/threads/mtx_unlock.h                 |  2 +-
 libc/src/threads/thrd_create.h                |  2 +-
 libc/src/threads/thrd_join.h                  |  2 +-
 libc/src/time/asctime.h                       |  2 +-
 libc/src/time/asctime_r.h                     |  2 +-
 libc/src/time/gmtime.h                        |  2 +-
 libc/src/time/gmtime_r.h                      |  2 +-
 libc/src/time/mktime.h                        |  2 +-
 libc/src/time/time_utils.h                    |  8 +--
 libc/src/unistd/write.h                       |  2 +-
 libc/utils/CPP/Array.h                        |  2 +-
 libc/utils/CPP/ArrayRef.h                     | 26 ++++-----
 libc/utils/FPUtil/BasicOperations.h           |  6 +-
 .../FPUtil/DivisionAndRemainderOperations.h   |  2 +-
 libc/utils/FPUtil/FPBits.h                    | 40 ++++++-------
 libc/utils/FPUtil/Hypot.h                     |  8 +--
 libc/utils/FPUtil/LongDoubleBitsX86.h         | 40 ++++++-------
 libc/utils/FPUtil/ManipulationFunctions.h     | 14 ++---
 libc/utils/FPUtil/NearestIntegerOperations.h  | 16 +++---
 libc/utils/FPUtil/NextAfterLongDoubleX86.h    |  2 +-
 libc/utils/FPUtil/NormalFloat.h               | 12 ++--
 libc/utils/FPUtil/PolyEval.h                  | 12 ++--
 libc/utils/FPUtil/Sqrt.h                      | 15 ++---
 libc/utils/FPUtil/SqrtLongDoubleX86.h         |  5 +-
 llvm/include/llvm/Support/Compiler.h          |  4 +-
 llvm/lib/TableGen/Error.cpp                   | 57 ++++++++-----------
 33 files changed, 136 insertions(+), 166 deletions(-)

diff --git a/libc/src/sys/mman/mmap.h b/libc/src/sys/mman/mmap.h
index 1cae4a7983d9d..c7aa404f65857 100644
--- a/libc/src/sys/mman/mmap.h
+++ b/libc/src/sys/mman/mmap.h
@@ -13,8 +13,7 @@
 
 namespace __llvm_libc {
 
-void *mmap(void *addr, size_t size, int prot, int flags, int fd,
-           off_t offset) noexcept;
+void *mmap(void *addr, size_t size, int prot, int flags, int fd, off_t offset);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/sys/mman/munmap.h b/libc/src/sys/mman/munmap.h
index 72cd7508be9d0..ba272dc45e15f 100644
--- a/libc/src/sys/mman/munmap.h
+++ b/libc/src/sys/mman/munmap.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-int munmap(void *addr, size_t size) noexcept;
+int munmap(void *addr, size_t size);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/threads/call_once.h b/libc/src/threads/call_once.h
index a4a8363594097..f6602df68197c 100644
--- a/libc/src/threads/call_once.h
+++ b/libc/src/threads/call_once.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-void call_once(once_flag *flag, __call_once_func_t func) noexcept;
+void call_once(once_flag *flag, __call_once_func_t func);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/threads/linux/thrd_create.cpp b/libc/src/threads/linux/thrd_create.cpp
index 449b4a4f25f98..8b68f2a48688d 100644
--- a/libc/src/threads/linux/thrd_create.cpp
+++ b/libc/src/threads/linux/thrd_create.cpp
@@ -30,7 +30,7 @@ struct StartArgs {
   void *arg;
 };
 
-static __attribute__((noinline)) void start_thread() noexcept {
+static __attribute__((noinline)) void start_thread() {
   StartArgs *start_args = reinterpret_cast<StartArgs *>(get_start_args_addr());
   __llvm_libc::syscall(SYS_exit, start_args->thread->__retval =
                                      start_args->func(start_args->arg));
diff --git a/libc/src/threads/linux/x86_64/thread_start_args.h.in b/libc/src/threads/linux/x86_64/thread_start_args.h.in
index 43e04ce4d34d5..36365b98bb214 100644
--- a/libc/src/threads/linux/x86_64/thread_start_args.h.in
+++ b/libc/src/threads/linux/x86_64/thread_start_args.h.in
@@ -10,7 +10,7 @@
 
 namespace __llvm_libc {
 
-__attribute__((always_inline)) inline uintptr_t get_start_args_addr() noexcept {
+__attribute__((always_inline)) inline uintptr_t get_start_args_addr() {
   // NOTE: For __builtin_frame_address to work reliably across compilers,
   // architectures and various optimization levels, the TU including this file
   // should be compiled with -fno-omit-frame-pointer.
diff --git a/libc/src/threads/mtx_init.h b/libc/src/threads/mtx_init.h
index a7302746a8ef5..7eed5ece6d5e7 100644
--- a/libc/src/threads/mtx_init.h
+++ b/libc/src/threads/mtx_init.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-int mtx_init(mtx_t *mutex, int type) noexcept;
+int mtx_init(mtx_t *mutex, int type);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/threads/mtx_lock.h b/libc/src/threads/mtx_lock.h
index 6afd9d6da5ad4..5086f773f0fe6 100644
--- a/libc/src/threads/mtx_lock.h
+++ b/libc/src/threads/mtx_lock.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-int mtx_lock(mtx_t *mutex) noexcept;
+int mtx_lock(mtx_t *mutex);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/threads/mtx_unlock.h b/libc/src/threads/mtx_unlock.h
index a28679993b495..55f0b4a7a6655 100644
--- a/libc/src/threads/mtx_unlock.h
+++ b/libc/src/threads/mtx_unlock.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-int mtx_unlock(mtx_t *mutex) noexcept;
+int mtx_unlock(mtx_t *mutex);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/threads/thrd_create.h b/libc/src/threads/thrd_create.h
index 859d2cbec7eb0..d2bb7dfad41c5 100644
--- a/libc/src/threads/thrd_create.h
+++ b/libc/src/threads/thrd_create.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-int thrd_create(thrd_t *thread, thrd_start_t func, void *arg) noexcept;
+int thrd_create(thrd_t *thread, thrd_start_t func, void *arg);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/threads/thrd_join.h b/libc/src/threads/thrd_join.h
index fa9f6ebc0a806..fc36503dc521c 100644
--- a/libc/src/threads/thrd_join.h
+++ b/libc/src/threads/thrd_join.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-int thrd_join(thrd_t *thread, int *retval) noexcept;
+int thrd_join(thrd_t *thread, int *retval);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/time/asctime.h b/libc/src/time/asctime.h
index c0c6bfa258794..9d75b40148afd 100644
--- a/libc/src/time/asctime.h
+++ b/libc/src/time/asctime.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-char *asctime(const struct tm *timeptr) noexcept;
+char *asctime(const struct tm *timeptr);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/time/asctime_r.h b/libc/src/time/asctime_r.h
index 56c75826bf4bc..8521e782a509d 100644
--- a/libc/src/time/asctime_r.h
+++ b/libc/src/time/asctime_r.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-char *asctime_r(const struct tm *timeptr, char *buffer) noexcept;
+char *asctime_r(const struct tm *timeptr, char *buffer);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/time/gmtime.h b/libc/src/time/gmtime.h
index 7203c743fc02b..8891a8c917ac5 100644
--- a/libc/src/time/gmtime.h
+++ b/libc/src/time/gmtime.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-struct tm *gmtime(const time_t *timer) noexcept;
+struct tm *gmtime(const time_t *timer);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/time/gmtime_r.h b/libc/src/time/gmtime_r.h
index 9476b6d82353d..8e9fc94b5ceed 100644
--- a/libc/src/time/gmtime_r.h
+++ b/libc/src/time/gmtime_r.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-struct tm *gmtime_r(const time_t *timer, struct tm *result) noexcept;
+struct tm *gmtime_r(const time_t *timer, struct tm *result);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/time/mktime.h b/libc/src/time/mktime.h
index b153cd24937a6..ecd604c12fc35 100644
--- a/libc/src/time/mktime.h
+++ b/libc/src/time/mktime.h
@@ -14,7 +14,7 @@
 
 namespace __llvm_libc {
 
-time_t mktime(struct tm *t1) noexcept;
+time_t mktime(struct tm *t1);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/time/time_utils.h b/libc/src/time/time_utils.h
index 327a6538a170c..c1c7735f49060 100644
--- a/libc/src/time/time_utils.h
+++ b/libc/src/time/time_utils.h
@@ -68,15 +68,15 @@ struct TimeConstants {
 extern int64_t UpdateFromSeconds(int64_t total_seconds, struct tm *tm);
 
 // POSIX.1-2017 requires this.
-static inline time_t OutOfRange() noexcept {
+static inline time_t OutOfRange() {
   llvmlibc_errno = EOVERFLOW;
   return static_cast<time_t>(-1);
 }
 
-static inline void InvalidValue() noexcept { llvmlibc_errno = EINVAL; }
+static inline void InvalidValue() { llvmlibc_errno = EINVAL; }
 
 static inline char *asctime(const struct tm *timeptr, char *buffer,
-                            size_t bufferLength) noexcept {
+                            size_t bufferLength) {
   if (timeptr == nullptr || buffer == nullptr) {
     InvalidValue();
     return nullptr;
@@ -114,7 +114,7 @@ static inline char *asctime(const struct tm *timeptr, char *buffer,
 }
 
 static inline struct tm *gmtime_internal(const time_t *timer,
-                                         struct tm *result) noexcept {
+                                         struct tm *result) {
   int64_t seconds = *timer;
   // Update the tm structure's year, month, day, etc. from seconds.
   if (UpdateFromSeconds(seconds, result) < 0) {
diff --git a/libc/src/unistd/write.h b/libc/src/unistd/write.h
index 0ad6981645604..d69c10a66f0f1 100644
--- a/libc/src/unistd/write.h
+++ b/libc/src/unistd/write.h
@@ -14,7 +14,7 @@
 
 namespace __llvm_libc {
 
-ssize_t write(int fd, const void *buf, size_t count) noexcept;
+ssize_t write(int fd, const void *buf, size_t count);
 
 } // namespace __llvm_libc
 
diff --git a/libc/utils/CPP/Array.h b/libc/utils/CPP/Array.h
index 9085ebd66f054..c774a9f793d8c 100644
--- a/libc/utils/CPP/Array.h
+++ b/libc/utils/CPP/Array.h
@@ -43,7 +43,7 @@ template <class T, size_t N> struct Array {
   constexpr const_iterator begin() const { return Data; }
 
   constexpr iterator end() { return Data + N; }
-  const_iterator end() const noexcept { return Data + N; }
+  const_iterator end() const { return Data + N; }
 };
 
 } // namespace cpp
diff --git a/libc/utils/CPP/ArrayRef.h b/libc/utils/CPP/ArrayRef.h
index 9df6b7d7e2c4e..cad7db9d3b663 100644
--- a/libc/utils/CPP/ArrayRef.h
+++ b/libc/utils/CPP/ArrayRef.h
@@ -50,46 +50,44 @@ template <typename QualifiedT> class ArrayRefBase {
   template <size_t N>
   constexpr ArrayRefBase(QualifiedT (&Arr)[N]) : Data(Arr), Length(N) {}
 
-  QualifiedT *data() const noexcept { return Data; }
-  size_t size() const noexcept { return Length; }
+  QualifiedT *data() const { return Data; }
+  size_t size() const { return Length; }
 
-  auto begin() const noexcept { return data(); }
-  auto end() const noexcept { return data() + size(); }
+  auto begin() const { return data(); }
+  auto end() const { return data() + size(); }
 
-  bool empty() const noexcept { return size() == 0; }
+  bool empty() const { return size() == 0; }
 
   auto operator[](size_t Index) const { return data()[Index]; }
 
   // slice(n, m) - Chop off the first N elements of the array, and keep M
   // elements in the array.
-  auto slice(size_t N, size_t M) const noexcept {
-    return ArrayRefBase(data() + N, M);
-  }
+  auto slice(size_t N, size_t M) const { return ArrayRefBase(data() + N, M); }
   // slice(n) - Chop off the first N elements of the array.
-  auto slice(size_t N) const noexcept { return slice(N, size() - N); }
+  auto slice(size_t N) const { return slice(N, size() - N); }
 
   // Drop the first \p N elements of the array.
-  auto drop_front(size_t N = 1) const noexcept { return slice(N, size() - N); }
+  auto drop_front(size_t N = 1) const { return slice(N, size() - N); }
 
   // Drop the last \p N elements of the array.
-  auto drop_back(size_t N = 1) const noexcept { return slice(0, size() - N); }
+  auto drop_back(size_t N = 1) const { return slice(0, size() - N); }
 
   // Return a copy of *this with only the first \p N elements.
-  auto take_front(size_t N = 1) const noexcept {
+  auto take_front(size_t N = 1) const {
     if (N >= size())
       return *this;
     return drop_back(size() - N);
   }
 
   // Return a copy of *this with only the last \p N elements.
-  auto take_back(size_t N = 1) const noexcept {
+  auto take_back(size_t N = 1) const {
     if (N >= size())
       return *this;
     return drop_front(size() - N);
   }
 
   // equals - Check for element-wise equality.
-  bool equals(ArrayRefBase<QualifiedT> RHS) const noexcept {
+  bool equals(ArrayRefBase<QualifiedT> RHS) const {
     if (Length != RHS.Length)
       return false;
     auto First1 = begin();
diff --git a/libc/utils/FPUtil/BasicOperations.h b/libc/utils/FPUtil/BasicOperations.h
index 877119dea5e69..43ccd12fdb70e 100644
--- a/libc/utils/FPUtil/BasicOperations.h
+++ b/libc/utils/FPUtil/BasicOperations.h
@@ -18,7 +18,7 @@ namespace fputil {
 
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T abs(T x) noexcept {
+static inline T abs(T x) {
   FPBits<T> bits(x);
   bits.setSign(0);
   return T(bits);
@@ -26,7 +26,7 @@ static inline T abs(T x) noexcept {
 
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T fmin(T x, T y) noexcept {
+static inline T fmin(T x, T y) {
   FPBits<T> bitx(x), bity(y);
 
   if (bitx.isNaN()) {
@@ -45,7 +45,7 @@ static inline T fmin(T x, T y) noexcept {
 
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T fmax(T x, T y) noexcept {
+static inline T fmax(T x, T y) {
   FPBits<T> bitx(x), bity(y);
 
   if (bitx.isNaN()) {
diff --git a/libc/utils/FPUtil/DivisionAndRemainderOperations.h b/libc/utils/FPUtil/DivisionAndRemainderOperations.h
index 9493b408b547a..d23a8daabbe63 100644
--- a/libc/utils/FPUtil/DivisionAndRemainderOperations.h
+++ b/libc/utils/FPUtil/DivisionAndRemainderOperations.h
@@ -24,7 +24,7 @@ static constexpr int quotientLSBBits = 3;
 // to evaluate the quotient and remainder.
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T remquo(T x, T y, int &q) noexcept {
+static inline T remquo(T x, T y, int &q) {
   FPBits<T> xbits(x), ybits(y);
   if (xbits.isNaN())
     return x;
diff --git a/libc/utils/FPUtil/FPBits.h b/libc/utils/FPUtil/FPBits.h
index fca93cfc04081..9ee870dc9983d 100644
--- a/libc/utils/FPUtil/FPBits.h
+++ b/libc/utils/FPUtil/FPBits.h
@@ -48,34 +48,32 @@ template <typename T> union FPBits {
 
   UIntType bits;
 
-  void setMantissa(UIntType mantVal) noexcept {
+  void setMantissa(UIntType mantVal) {
     mantVal &= (FloatProp::mantissaMask);
     bits &= ~(FloatProp::mantissaMask);
     bits |= mantVal;
   }
 
-  UIntType getMantissa() const noexcept {
-    return bits & FloatProp::mantissaMask;
-  }
+  UIntType getMantissa() const { return bits & FloatProp::mantissaMask; }
 
-  void setUnbiasedExponent(UIntType expVal) noexcept {
+  void setUnbiasedExponent(UIntType expVal) {
     expVal = (expVal << (FloatProp::mantissaWidth)) & FloatProp::exponentMask;
     bits &= ~(FloatProp::exponentMask);
     bits |= expVal;
   }
 
-  uint16_t getUnbiasedExponent() const noexcept {
+  uint16_t getUnbiasedExponent() const {
     return uint16_t((bits & FloatProp::exponentMask) >>
                     (FloatProp::mantissaWidth));
   }
 
-  void setSign(bool signVal) noexcept {
+  void setSign(bool signVal) {
     bits &= ~(FloatProp::signMask);
     UIntType sign = UIntType(signVal) << (FloatProp::bitWidth - 1);
     bits |= sign;
   }
 
-  bool getSign() const noexcept {
+  bool getSign() const {
     return ((bits & FloatProp::signMask) >> (FloatProp::bitWidth - 1));
   }
   T val;
@@ -108,47 +106,43 @@ template <typename T> union FPBits {
 
   explicit operator T() { return val; }
 
-  UIntType uintval() const noexcept { return bits; }
+  UIntType uintval() const { return bits; }
 
-  int getExponent() const noexcept {
-    return int(getUnbiasedExponent()) - exponentBias;
-  }
+  int getExponent() const { return int(getUnbiasedExponent()) - exponentBias; }
 
-  bool isZero() const noexcept {
+  bool isZero() const {
     return getMantissa() == 0 && getUnbiasedExponent() == 0;
   }
 
-  bool isInf() const noexcept {
+  bool isInf() const {
     return getMantissa() == 0 && getUnbiasedExponent() == maxExponent;
   }
 
-  bool isNaN() const noexcept {
+  bool isNaN() const {
     return getUnbiasedExponent() == maxExponent && getMantissa() != 0;
   }
 
-  bool isInfOrNaN() const noexcept {
-    return getUnbiasedExponent() == maxExponent;
-  }
+  bool isInfOrNaN() const { return getUnbiasedExponent() == maxExponent; }
 
-  static FPBits<T> zero() noexcept { return FPBits(); }
+  static FPBits<T> zero() { return FPBits(); }
 
-  static FPBits<T> negZero() noexcept {
+  static FPBits<T> negZero() {
     return FPBits(UIntType(1) << (sizeof(UIntType) * 8 - 1));
   }
 
-  static FPBits<T> inf() noexcept {
+  static FPBits<T> inf() {
     FPBits<T> bits;
     bits.setUnbiasedExponent(maxExponent);
     return bits;
   }
 
-  static FPBits<T> negInf() noexcept {
+  static FPBits<T> negInf() {
     FPBits<T> bits = inf();
     bits.setSign(1);
     return bits;
   }
 
-  static T buildNaN(UIntType v) noexcept {
+  static T buildNaN(UIntType v) {
     FPBits<T> bits = inf();
     bits.setMantissa(v);
     return T(bits);
diff --git a/libc/utils/FPUtil/Hypot.h b/libc/utils/FPUtil/Hypot.h
index a3983dafc6ce8..8d108a74761de 100644
--- a/libc/utils/FPUtil/Hypot.h
+++ b/libc/utils/FPUtil/Hypot.h
@@ -18,10 +18,10 @@ namespace fputil {
 
 namespace internal {
 
-template <typename T> static inline T findLeadingOne(T mant, int &shift_length) noexcept;
+template <typename T> static inline T findLeadingOne(T mant, int &shift_length);
 
 template <>
-inline uint32_t findLeadingOne<uint32_t>(uint32_t mant, int &shift_length) noexcept {
+inline uint32_t findLeadingOne<uint32_t>(uint32_t mant, int &shift_length) {
   shift_length = 0;
   constexpr int nsteps = 5;
   constexpr uint32_t bounds[nsteps] = {1 << 16, 1 << 8, 1 << 4, 1 << 2, 1 << 1};
@@ -36,7 +36,7 @@ inline uint32_t findLeadingOne<uint32_t>(uint32_t mant, int &shift_length) noexc
 }
 
 template <>
-inline uint64_t findLeadingOne<uint64_t>(uint64_t mant, int &shift_length) noexcept {
+inline uint64_t findLeadingOne<uint64_t>(uint64_t mant, int &shift_length) {
   shift_length = 0;
   constexpr int nsteps = 6;
   constexpr uint64_t bounds[nsteps] = {1ULL << 32, 1ULL << 16, 1ULL << 8,
@@ -117,7 +117,7 @@ template <> struct DoubleLength<uint64_t> { using Type = __uint128_t; };
 //
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T hypot(T x, T y) noexcept {
+static inline T hypot(T x, T y) {
   using FPBits_t = FPBits<T>;
   using UIntType = typename FPBits<T>::UIntType;
   using DUIntType = typename DoubleLength<UIntType>::Type;
diff --git a/libc/utils/FPUtil/LongDoubleBitsX86.h b/libc/utils/FPUtil/LongDoubleBitsX86.h
index 04c155b48a41f..ce7fdb1b0fa8a 100644
--- a/libc/utils/FPUtil/LongDoubleBitsX86.h
+++ b/libc/utils/FPUtil/LongDoubleBitsX86.h
@@ -43,45 +43,43 @@ template <> union FPBits<long double> {
 
   UIntType bits;
 
-  void setMantissa(UIntType mantVal) noexcept {
+  void setMantissa(UIntType mantVal) {
     mantVal &= (FloatProp::mantissaMask);
     bits &= ~(FloatProp::mantissaMask);
     bits |= mantVal;
   }
 
-  UIntType getMantissa() const noexcept {
-    return bits & FloatProp::mantissaMask;
-  }
+  UIntType getMantissa() const { return bits & FloatProp::mantissaMask; }
 
-  void setUnbiasedExponent(UIntType expVal) noexcept {
+  void setUnbiasedExponent(UIntType expVal) {
     expVal = (expVal << (FloatProp::bitWidth - 1 - FloatProp::exponentWidth)) &
              FloatProp::exponentMask;
     bits &= ~(FloatProp::exponentMask);
     bits |= expVal;
   }
 
-  uint16_t getUnbiasedExponent() const noexcept {
+  uint16_t getUnbiasedExponent() const {
     return uint16_t((bits & FloatProp::exponentMask) >>
                     (FloatProp::bitWidth - 1 - FloatProp::exponentWidth));
   }
 
-  void setImplicitBit(bool implicitVal) noexcept {
+  void setImplicitBit(bool implicitVal) {
     bits &= ~(UIntType(1) << FloatProp::mantissaWidth);
     bits |= (UIntType(implicitVal) << FloatProp::mantissaWidth);
   }
 
-  bool getImplicitBit() const noexcept {
+  bool getImplicitBit() const {
     return ((bits & (UIntType(1) << FloatProp::mantissaWidth)) >>
             FloatProp::mantissaWidth);
   }
 
-  void setSign(bool signVal) noexcept {
+  void setSign(bool signVal) {
     bits &= ~(FloatProp::signMask);
     UIntType sign1 = UIntType(signVal) << (FloatProp::bitWidth - 1);
     bits |= sign1;
   }
 
-  bool getSign() const noexcept {
+  bool getSign() const {
     return ((bits & FloatProp::signMask) >> (FloatProp::bitWidth - 1));
   }
 
@@ -108,23 +106,23 @@ template <> union FPBits<long double> {
     return bits & mask;
   }
 
-  int getExponent() const noexcept {
+  int getExponent() const {
     if (getUnbiasedExponent() == 0)
       return int(1) - exponentBias;
     return int(getUnbiasedExponent()) - exponentBias;
   }
 
-  bool isZero() const noexcept {
+  bool isZero() const {
     return getUnbiasedExponent() == 0 && getMantissa() == 0 &&
            getImplicitBit() == 0;
   }
 
-  bool isInf() const noexcept {
+  bool isInf() const {
     return getUnbiasedExponent() == maxExponent && getMantissa() == 0 &&
            getImplicitBit() == 1;
   }
 
-  bool isNaN() const noexcept {
+  bool isNaN() const {
     if (getUnbiasedExponent() == maxExponent) {
       return (getImplicitBit() == 0) || getMantissa() != 0;
     } else if (getUnbiasedExponent() != 0) {
@@ -133,31 +131,29 @@ template <> union FPBits<long double> {
     return false;
   }
 
-  bool isInfOrNaN() const noexcept {
+  bool isInfOrNaN() const {
     return (getUnbiasedExponent() == maxExponent) ||
            (getUnbiasedExponent() != 0 && getImplicitBit() == 0);
   }
 
   // Methods below this are used by tests.
 
-  static FPBits<long double> zero() noexcept {
-    return FPBits<long double>(0.0l);
-  }
+  static FPBits<long double> zero() { return FPBits<long double>(0.0l); }
 
-  static FPBits<long double> negZero() noexcept {
+  static FPBits<long double> negZero() {
     FPBits<long double> bits(0.0l);
     bits.setSign(1);
     return bits;
   }
 
-  static FPBits<long double> inf() noexcept {
+  static FPBits<long double> inf() {
     FPBits<long double> bits(0.0l);
     bits.setUnbiasedExponent(maxExponent);
     bits.setImplicitBit(1);
     return bits;
   }
 
-  static FPBits<long double> negInf() noexcept {
+  static FPBits<long double> negInf() {
     FPBits<long double> bits(0.0l);
     bits.setUnbiasedExponent(maxExponent);
     bits.setImplicitBit(1);
@@ -165,7 +161,7 @@ template <> union FPBits<long double> {
     return bits;
   }
 
-  static long double buildNaN(UIntType v) noexcept {
+  static long double buildNaN(UIntType v) {
     FPBits<long double> bits(0.0l);
     bits.setUnbiasedExponent(maxExponent);
     bits.setImplicitBit(1);
diff --git a/libc/utils/FPUtil/ManipulationFunctions.h b/libc/utils/FPUtil/ManipulationFunctions.h
index ee06166c46b1a..545e5f0f24288 100644
--- a/libc/utils/FPUtil/ManipulationFunctions.h
+++ b/libc/utils/FPUtil/ManipulationFunctions.h
@@ -24,7 +24,7 @@ namespace fputil {
 
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T frexp(T x, int &exp) noexcept {
+static inline T frexp(T x, int &exp) {
   FPBits<T> bits(x);
   if (bits.isInfOrNaN())
     return x;
@@ -41,7 +41,7 @@ static inline T frexp(T x, int &exp) noexcept {
 
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T modf(T x, T &iptr) noexcept {
+static inline T modf(T x, T &iptr) {
   FPBits<T> bits(x);
   if (bits.isZero() || bits.isNaN()) {
     iptr = x;
@@ -63,7 +63,7 @@ static inline T modf(T x, T &iptr) noexcept {
 
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T copysign(T x, T y) noexcept {
+static inline T copysign(T x, T y) {
   FPBits<T> xbits(x);
   xbits.setSign(FPBits<T>(y).getSign());
   return T(xbits);
@@ -71,7 +71,7 @@ static inline T copysign(T x, T y) noexcept {
 
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline int ilogb(T x) noexcept {
+static inline int ilogb(T x) {
   // TODO: Raise appropriate floating point exceptions and set errno to the
   // an appropriate error value wherever relevant.
   FPBits<T> bits(x);
@@ -100,7 +100,7 @@ static inline int ilogb(T x) noexcept {
 
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T logb(T x) noexcept {
+static inline T logb(T x) {
   FPBits<T> bits(x);
   if (bits.isZero()) {
     // TODO(Floating point exception): Raise div-by-zero exception.
@@ -119,7 +119,7 @@ static inline T logb(T x) noexcept {
 
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T ldexp(T x, int exp) noexcept {
+static inline T ldexp(T x, int exp) {
   FPBits<T> bits(x);
   if (bits.isZero() || bits.isInfOrNaN() || exp == 0)
     return x;
@@ -146,7 +146,7 @@ static inline T ldexp(T x, int exp) noexcept {
 
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T nextafter(T from, T to) noexcept {
+static inline T nextafter(T from, T to) {
   FPBits<T> fromBits(from);
   if (fromBits.isNaN())
     return from;
diff --git a/libc/utils/FPUtil/NearestIntegerOperations.h b/libc/utils/FPUtil/NearestIntegerOperations.h
index cc0b5142197ba..8dc4e23ce75c1 100644
--- a/libc/utils/FPUtil/NearestIntegerOperations.h
+++ b/libc/utils/FPUtil/NearestIntegerOperations.h
@@ -24,7 +24,7 @@ namespace fputil {
 
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T trunc(T x) noexcept {
+static inline T trunc(T x) {
   FPBits<T> bits(x);
 
   // If x is infinity or NaN, return it.
@@ -56,7 +56,7 @@ static inline T trunc(T x) noexcept {
 
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T ceil(T x) noexcept {
+static inline T ceil(T x) {
   FPBits<T> bits(x);
 
   // If x is infinity NaN or zero, return it.
@@ -95,7 +95,7 @@ static inline T ceil(T x) noexcept {
 
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T floor(T x) noexcept {
+static inline T floor(T x) {
   FPBits<T> bits(x);
   if (bits.getSign()) {
     return -ceil(-x);
@@ -106,7 +106,7 @@ static inline T floor(T x) noexcept {
 
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T round(T x) noexcept {
+static inline T round(T x) {
   using UIntType = typename FPBits<T>::UIntType;
   FPBits<T> bits(x);
 
@@ -158,7 +158,7 @@ static inline T round(T x) noexcept {
 
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T roundUsingCurrentRoundingMode(T x) noexcept {
+static inline T roundUsingCurrentRoundingMode(T x) {
   using UIntType = typename FPBits<T>::UIntType;
   FPBits<T> bits(x);
 
@@ -240,7 +240,7 @@ template <typename F, typename I,
           cpp::EnableIfType<cpp::IsFloatingPointType<F>::Value &&
                                 cpp::IsIntegral<I>::Value,
                             int> = 0>
-static inline I roundedFloatToSignedInteger(F x) noexcept {
+static inline I roundedFloatToSignedInteger(F x) {
   constexpr I IntegerMin = (I(1) << (sizeof(I) * 8 - 1));
   constexpr I IntegerMax = -(IntegerMin + 1);
   FPBits<F> bits(x);
@@ -284,7 +284,7 @@ template <typename F, typename I,
           cpp::EnableIfType<cpp::IsFloatingPointType<F>::Value &&
                                 cpp::IsIntegral<I>::Value,
                             int> = 0>
-static inline I roundToSignedInteger(F x) noexcept {
+static inline I roundToSignedInteger(F x) {
   return internal::roundedFloatToSignedInteger<F, I>(round(x));
 }
 
@@ -292,7 +292,7 @@ template <typename F, typename I,
           cpp::EnableIfType<cpp::IsFloatingPointType<F>::Value &&
                                 cpp::IsIntegral<I>::Value,
                             int> = 0>
-static inline I roundToSignedIntegerUsingCurrentRoundingMode(F x) noexcept {
+static inline I roundToSignedIntegerUsingCurrentRoundingMode(F x) {
   return internal::roundedFloatToSignedInteger<F, I>(
       roundUsingCurrentRoundingMode(x));
 }
diff --git a/libc/utils/FPUtil/NextAfterLongDoubleX86.h b/libc/utils/FPUtil/NextAfterLongDoubleX86.h
index ea91c02140ffa..80ca9ad084cb2 100644
--- a/libc/utils/FPUtil/NextAfterLongDoubleX86.h
+++ b/libc/utils/FPUtil/NextAfterLongDoubleX86.h
@@ -16,7 +16,7 @@
 namespace __llvm_libc {
 namespace fputil {
 
-static inline long double nextafter(long double from, long double to) noexcept {
+static inline long double nextafter(long double from, long double to) {
   using FPBits = FPBits<long double>;
   FPBits fromBits(from);
   if (fromBits.isNaN())
diff --git a/libc/utils/FPUtil/NormalFloat.h b/libc/utils/FPUtil/NormalFloat.h
index 024d3e6f8f0d2..2d50e88db9167 100644
--- a/libc/utils/FPUtil/NormalFloat.h
+++ b/libc/utils/FPUtil/NormalFloat.h
@@ -45,7 +45,7 @@ template <typename T> struct NormalFloat {
   bool sign;
 
   NormalFloat(int32_t e, UIntType m, bool s)
-      : exponent(e), mantissa(m), sign(s) noexcept {
+      : exponent(e), mantissa(m), sign(s) {
     if (mantissa >= one)
       return;
 
@@ -61,7 +61,7 @@ template <typename T> struct NormalFloat {
   // Compares this normalized number with another normalized number.
   // Returns -1 is this number is less than |other|, 0 if this number is equal
   // to |other|, and 1 if this number is greater than |other|.
-  int cmp(const NormalFloat<T> &other) const noexcept {
+  int cmp(const NormalFloat<T> &other) const {
     if (sign != other.sign)
       return sign ? -1 : 1;
 
@@ -82,7 +82,7 @@ template <typename T> struct NormalFloat {
   // Returns a new normalized floating point number which is equal in value
   // to this number multiplied by 2^e. That is:
   //     new = this *  2^e
-  NormalFloat<T> mul2(int e) const noexcept {
+  NormalFloat<T> mul2(int e) const {
     NormalFloat<T> result = *this;
     result.exponent += e;
     return result;
@@ -138,7 +138,7 @@ template <typename T> struct NormalFloat {
   }
 
 private:
-  void initFromBits(FPBits<T> bits) noexcept {
+  void initFromBits(FPBits<T> bits) {
     sign = bits.getSign();
 
     if (bits.isInfOrNaN() || bits.isZero()) {
@@ -160,7 +160,7 @@ template <typename T> struct NormalFloat {
     }
   }
 
-  unsigned evaluateNormalizationShift(UIntType m) noexcept {
+  unsigned evaluateNormalizationShift(UIntType m) {
     unsigned shift = 0;
     for (; (one & m) == 0 && (shift < MantissaWidth<T>::value);
          m <<= 1, ++shift)
@@ -171,7 +171,7 @@ template <typename T> struct NormalFloat {
 
 #ifdef SPECIAL_X86_LONG_DOUBLE
 template <>
-inline void NormalFloat<long double>::initFromBits(FPBits<long double> bits) noexcept {
+inline void NormalFloat<long double>::initFromBits(FPBits<long double> bits) {
   sign = bits.getSign();
 
   if (bits.isInfOrNaN() || bits.isZero()) {
diff --git a/libc/utils/FPUtil/PolyEval.h b/libc/utils/FPUtil/PolyEval.h
index 313f57bcd032c..ce8377fe895a1 100644
--- a/libc/utils/FPUtil/PolyEval.h
+++ b/libc/utils/FPUtil/PolyEval.h
@@ -24,12 +24,10 @@
 namespace __llvm_libc {
 namespace fputil {
 
-template <typename T> static inline T polyeval(T x, T a0) noexcept {
-  return a0;
-}
+template <typename T> static inline T polyeval(T x, T a0) { return a0; }
 
 template <typename T, typename... Ts>
-static inline T polyeval(T x, T a0, Ts... a) noexcept {
+static inline T polyeval(T x, T a0, Ts... a) {
   return fma(x, polyeval(x, a...), a0);
 }
 
@@ -41,12 +39,10 @@ static inline T polyeval(T x, T a0, Ts... a) noexcept {
 namespace __llvm_libc {
 namespace fputil {
 
-template <typename T> static inline T polyeval(T x, T a0) noexcept {
-  return a0;
-}
+template <typename T> static inline T polyeval(T x, T a0) { return a0; }
 
 template <typename T, typename... Ts>
-static inline T polyeval(T x, T a0, Ts... a) noexcept {
+static inline T polyeval(T x, T a0, Ts... a) {
   return x * polyeval(x, a...) + a0;
 }
 
diff --git a/libc/utils/FPUtil/Sqrt.h b/libc/utils/FPUtil/Sqrt.h
index a15a0eb4cf9cb..b977bc2ef8773 100644
--- a/libc/utils/FPUtil/Sqrt.h
+++ b/libc/utils/FPUtil/Sqrt.h
@@ -21,10 +21,9 @@ namespace internal {
 
 template <typename T>
 static inline void normalize(int &exponent,
-                             typename FPBits<T>::UIntType &mantissa) noexcept;
+                             typename FPBits<T>::UIntType &mantissa);
 
-template <>
-inline void normalize<float>(int &exponent, uint32_t &mantissa) noexcept {
+template <> inline void normalize<float>(int &exponent, uint32_t &mantissa) {
   // Use binary search to shift the leading 1 bit.
   // With MantissaWidth<float> = 23, it will take
   // ceil(log2(23)) = 5 steps checking the mantissa bits as followed:
@@ -46,8 +45,7 @@ inline void normalize<float>(int &exponent, uint32_t &mantissa) noexcept {
   }
 }
 
-template <>
-inline void normalize<double>(int &exponent, uint64_t &mantissa) noexcept {
+template <> inline void normalize<double>(int &exponent, uint64_t &mantissa) {
   // Use binary search to shift the leading 1 bit similar to float.
   // With MantissaWidth<double> = 52, it will take
   // ceil(log2(52)) = 6 steps checking the mantissa bits.
@@ -66,13 +64,12 @@ inline void normalize<double>(int &exponent, uint64_t &mantissa) noexcept {
 
 #ifdef LONG_DOUBLE_IS_DOUBLE
 template <>
-inline void normalize<long double>(int &exponent, uint64_t &mantissa) noexcept {
+inline void normalize<long double>(int &exponent, uint64_t &mantissa) {
   normalize<double>(exponent, mantissa);
 }
 #elif !defined(SPECIAL_X86_LONG_DOUBLE)
 template <>
-inline void normalize<long double>(int &exponent,
-                                   __uint128_t &mantissa) noexcept {
+inline void normalize<long double>(int &exponent, __uint128_t &mantissa) {
   // Use binary search to shift the leading 1 bit similar to float.
   // With MantissaWidth<long double> = 112, it will take
   // ceil(log2(112)) = 7 steps checking the mantissa bits.
@@ -98,7 +95,7 @@ inline void normalize<long double>(int &exponent,
 // Shift-and-add algorithm.
 template <typename T,
           cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T sqrt(T x) noexcept {
+static inline T sqrt(T x) {
   using UIntType = typename FPBits<T>::UIntType;
   constexpr UIntType One = UIntType(1) << MantissaWidth<T>::value;
 
diff --git a/libc/utils/FPUtil/SqrtLongDoubleX86.h b/libc/utils/FPUtil/SqrtLongDoubleX86.h
index 2b21647550f3c..58326183678b8 100644
--- a/libc/utils/FPUtil/SqrtLongDoubleX86.h
+++ b/libc/utils/FPUtil/SqrtLongDoubleX86.h
@@ -20,8 +20,7 @@ namespace fputil {
 namespace internal {
 
 template <>
-inline void normalize<long double>(int &exponent,
-                                   __uint128_t &mantissa) noexcept {
+inline void normalize<long double>(int &exponent, __uint128_t &mantissa) {
   // Use binary search to shift the leading 1 bit similar to float.
   // With MantissaWidth<long double> = 63, it will take
   // ceil(log2(63)) = 6 steps checking the mantissa bits.
@@ -43,7 +42,7 @@ inline void normalize<long double>(int &exponent,
 
 // Correctly rounded SQRT with round to nearest, ties to even.
 // Shift-and-add algorithm.
-template <> inline long double sqrt<long double, 0>(long double x) noexcept {
+template <> inline long double sqrt<long double, 0>(long double x) {
   using UIntType = typename FPBits<long double>::UIntType;
   constexpr UIntType One = UIntType(1)
                            << int(MantissaWidth<long double>::value);
diff --git a/llvm/include/llvm/Support/Compiler.h b/llvm/include/llvm/Support/Compiler.h
index ec90f75719470..57052b596edbe 100644
--- a/llvm/include/llvm/Support/Compiler.h
+++ b/llvm/include/llvm/Support/Compiler.h
@@ -246,10 +246,8 @@
 #define LLVM_ATTRIBUTE_NORETURN __attribute__((noreturn))
 #elif defined(_MSC_VER)
 #define LLVM_ATTRIBUTE_NORETURN __declspec(noreturn)
-#elif __cplusplus
-#define LLVM_ATTRIBUTE_NORETURN [[noreturn]]
 #else
-#define LLVM_ATTRIBUTE_NORETURN _Noreturn
+#define LLVM_ATTRIBUTE_NORETURN
 #endif
 
 #if __has_attribute(returns_nonnull) || LLVM_GNUC_PREREQ(4, 9, 0)
diff --git a/llvm/lib/TableGen/Error.cpp b/llvm/lib/TableGen/Error.cpp
index cf7c4dd129499..6104573b4b25b 100644
--- a/llvm/lib/TableGen/Error.cpp
+++ b/llvm/lib/TableGen/Error.cpp
@@ -11,11 +11,11 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include "llvm/TableGen/Error.h"
 #include "llvm/ADT/Twine.h"
+#include "llvm/Support/raw_ostream.h"
 #include "llvm/Support/Signals.h"
 #include "llvm/Support/WithColor.h"
-#include "llvm/Support/raw_ostream.h"
+#include "llvm/TableGen/Error.h"
 #include "llvm/TableGen/Record.h"
 #include <cstdlib>
 
@@ -25,7 +25,7 @@ SourceMgr SrcMgr;
 unsigned ErrorsPrinted = 0;
 
 static void PrintMessage(ArrayRef<SMLoc> Loc, SourceMgr::DiagKind Kind,
-                         const Twine &Msg) noexcept {
+                         const Twine &Msg) {
   // Count the total number of errors printed.
   // This is used to exit with an error code if there were any errors.
   if (Kind == SourceMgr::DK_Error)
@@ -42,23 +42,24 @@ static void PrintMessage(ArrayRef<SMLoc> Loc, SourceMgr::DiagKind Kind,
 
 // Functions to print notes.
 
-void PrintNote(const Twine &Msg) noexcept { WithColor::note() << Msg << "\n"; }
+void PrintNote(const Twine &Msg) {
+  WithColor::note() << Msg << "\n";
+}
 
-void PrintNote(ArrayRef<SMLoc> NoteLoc, const Twine &Msg) noexcept {
+void PrintNote(ArrayRef<SMLoc> NoteLoc, const Twine &Msg) {
   PrintMessage(NoteLoc, SourceMgr::DK_Note, Msg);
 }
 
 // Functions to print fatal notes.
 
-LLVM_ATTRIBUTE_NORETURN void PrintFatalNote(const Twine &Msg) noexcept {
+void PrintFatalNote(const Twine &Msg) {
   PrintNote(Msg);
   // The following call runs the file cleanup handlers.
   sys::RunInterruptHandlers();
   std::exit(1);
 }
 
-LLVM_ATTRIBUTE_NORETURN void PrintFatalNote(ArrayRef<SMLoc> NoteLoc,
-                                 const Twine &Msg) noexcept {
+void PrintFatalNote(ArrayRef<SMLoc> NoteLoc, const Twine &Msg) {
   PrintNote(NoteLoc, Msg);
   // The following call runs the file cleanup handlers.
   sys::RunInterruptHandlers();
@@ -67,7 +68,7 @@ LLVM_ATTRIBUTE_NORETURN void PrintFatalNote(ArrayRef<SMLoc> NoteLoc,
 
 // This method takes a Record and uses the source location
 // stored in it.
-LLVM_ATTRIBUTE_NORETURN void PrintFatalNote(const Record *Rec, const Twine &Msg) noexcept {
+void PrintFatalNote(const Record *Rec, const Twine &Msg) {
   PrintNote(Rec->getLoc(), Msg);
   // The following call runs the file cleanup handlers.
   sys::RunInterruptHandlers();
@@ -76,8 +77,7 @@ LLVM_ATTRIBUTE_NORETURN void PrintFatalNote(const Record *Rec, const Twine &Msg)
 
 // This method takes a RecordVal and uses the source location
 // stored in it.
-LLVM_ATTRIBUTE_NORETURN void PrintFatalNote(const RecordVal *RecVal,
-                                 const Twine &Msg) noexcept {
+void PrintFatalNote(const RecordVal *RecVal, const Twine &Msg) {
   PrintNote(RecVal->getLoc(), Msg);
   // The following call runs the file cleanup handlers.
   sys::RunInterruptHandlers();
@@ -86,55 +86,50 @@ LLVM_ATTRIBUTE_NORETURN void PrintFatalNote(const RecordVal *RecVal,
 
 // Functions to print warnings.
 
-void PrintWarning(const Twine &Msg) noexcept {
-  WithColor::warning() << Msg << "\n";
-}
+void PrintWarning(const Twine &Msg) { WithColor::warning() << Msg << "\n"; }
 
-void PrintWarning(ArrayRef<SMLoc> WarningLoc, const Twine &Msg) noexcept {
+void PrintWarning(ArrayRef<SMLoc> WarningLoc, const Twine &Msg) {
   PrintMessage(WarningLoc, SourceMgr::DK_Warning, Msg);
 }
 
-void PrintWarning(const char *Loc, const Twine &Msg) noexcept {
+void PrintWarning(const char *Loc, const Twine &Msg) {
   SrcMgr.PrintMessage(SMLoc::getFromPointer(Loc), SourceMgr::DK_Warning, Msg);
 }
 
 // Functions to print errors.
 
-void PrintError(const Twine &Msg) noexcept {
-  WithColor::error() << Msg << "\n";
-}
+void PrintError(const Twine &Msg) { WithColor::error() << Msg << "\n"; }
 
-void PrintError(ArrayRef<SMLoc> ErrorLoc, const Twine &Msg) noexcept {
+void PrintError(ArrayRef<SMLoc> ErrorLoc, const Twine &Msg) {
   PrintMessage(ErrorLoc, SourceMgr::DK_Error, Msg);
 }
 
-void PrintError(const char *Loc, const Twine &Msg) noexcept {
+void PrintError(const char *Loc, const Twine &Msg) {
   SrcMgr.PrintMessage(SMLoc::getFromPointer(Loc), SourceMgr::DK_Error, Msg);
 }
 
 // This method takes a Record and uses the source location
 // stored in it.
-void PrintError(const Record *Rec, const Twine &Msg) noexcept {
+void PrintError(const Record *Rec, const Twine &Msg) {
   PrintMessage(Rec->getLoc(), SourceMgr::DK_Error, Msg);
 }
 
 // This method takes a RecordVal and uses the source location
 // stored in it.
-void PrintError(const RecordVal *RecVal, const Twine &Msg) noexcept {
+void PrintError(const RecordVal *RecVal, const Twine &Msg) {
   PrintMessage(RecVal->getLoc(), SourceMgr::DK_Error, Msg);
 }
 
 // Functions to print fatal errors.
 
-[[noreturn]] void PrintFatalError(const Twine &Msg) noexcept {
+void PrintFatalError(const Twine &Msg) {
   PrintError(Msg);
   // The following call runs the file cleanup handlers.
   sys::RunInterruptHandlers();
   std::exit(1);
 }
 
-[[noreturn]] void PrintFatalError(ArrayRef<SMLoc> ErrorLoc,
-                                  const Twine &Msg) noexcept {
+void PrintFatalError(ArrayRef<SMLoc> ErrorLoc, const Twine &Msg) {
   PrintError(ErrorLoc, Msg);
   // The following call runs the file cleanup handlers.
   sys::RunInterruptHandlers();
@@ -143,8 +138,7 @@ void PrintError(const RecordVal *RecVal, const Twine &Msg) noexcept {
 
 // This method takes a Record and uses the source location
 // stored in it.
-[[noreturn]] void PrintFatalError(const Record *Rec,
-                                  const Twine &Msg) noexcept {
+void PrintFatalError(const Record *Rec, const Twine &Msg) {
   PrintError(Rec->getLoc(), Msg);
   // The following call runs the file cleanup handlers.
   sys::RunInterruptHandlers();
@@ -153,8 +147,7 @@ void PrintError(const RecordVal *RecVal, const Twine &Msg) noexcept {
 
 // This method takes a RecordVal and uses the source location
 // stored in it.
-[[noreturn]] void PrintFatalError(const RecordVal *RecVal,
-                                  const Twine &Msg) noexcept {
+void PrintFatalError(const RecordVal *RecVal, const Twine &Msg) {
   PrintError(RecVal->getLoc(), Msg);
   // The following call runs the file cleanup handlers.
   sys::RunInterruptHandlers();
@@ -163,9 +156,9 @@ void PrintError(const RecordVal *RecVal, const Twine &Msg) noexcept {
 
 // Check an assertion: Obtain the condition value and be sure it is true.
 // If not, print a nonfatal error along with the message.
-void CheckAssert(SMLoc Loc, Init *Condition, Init *Message) noexcept {
+void CheckAssert(SMLoc Loc, Init *Condition, Init *Message) {
   auto *CondValue = dyn_cast_or_null<IntInit>(
-      Condition->convertInitializerTo(IntRecTy::get()));
+                        Condition->convertInitializerTo(IntRecTy::get()));
   if (!CondValue)
     PrintError(Loc, "assert condition must of type bit, bits, or int.");
   else if (!CondValue->getValue()) {

From abaaed473edffc1fbc2dddfa8785a146bfc29eb4 Mon Sep 17 00:00:00 2001
From: Alfonso Gregory <83477269+gAlfonso-bit@users.noreply.github.com>
Date: Mon, 26 Jul 2021 13:31:39 -0400
Subject: [PATCH 13/17] OK

---
 llvm/include/llvm/Support/Compiler.h | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/llvm/include/llvm/Support/Compiler.h b/llvm/include/llvm/Support/Compiler.h
index 57052b596edbe..ec90f75719470 100644
--- a/llvm/include/llvm/Support/Compiler.h
+++ b/llvm/include/llvm/Support/Compiler.h
@@ -246,8 +246,10 @@
 #define LLVM_ATTRIBUTE_NORETURN __attribute__((noreturn))
 #elif defined(_MSC_VER)
 #define LLVM_ATTRIBUTE_NORETURN __declspec(noreturn)
+#elif __cplusplus
+#define LLVM_ATTRIBUTE_NORETURN [[noreturn]]
 #else
-#define LLVM_ATTRIBUTE_NORETURN
+#define LLVM_ATTRIBUTE_NORETURN _Noreturn
 #endif
 
 #if __has_attribute(returns_nonnull) || LLVM_GNUC_PREREQ(4, 9, 0)

From a93e9b919c0fc4ac42fe3457da2d3fde30c82e01 Mon Sep 17 00:00:00 2001
From: Alfonso Gregory <83477269+gAlfonso-bit@users.noreply.github.com>
Date: Mon, 26 Jul 2021 13:34:15 -0400
Subject: [PATCH 14/17] Fix

---
 libc/src/__support/common.h | 4 ++--
 libc/src/ctype/isalpha.h    | 2 +-
 libc/src/ctype/isascii.h    | 2 +-
 libc/src/ctype/isblank.h    | 2 +-
 libc/src/ctype/iscntrl.h    | 2 +-
 libc/src/ctype/isdigit.h    | 2 +-
 libc/src/ctype/isgraph.h    | 2 +-
 libc/src/ctype/islower.h    | 2 +-
 libc/src/ctype/isprint.h    | 2 +-
 libc/src/ctype/ispunct.h    | 2 +-
 libc/src/ctype/isspace.h    | 2 +-
 libc/src/ctype/isupper.h    | 2 +-
 libc/src/ctype/isxdigit.h   | 2 +-
 libc/src/ctype/toascii.h    | 2 +-
 libc/src/ctype/tolower.h    | 2 +-
 libc/src/ctype/toupper.h    | 2 +-
 16 files changed, 17 insertions(+), 17 deletions(-)

diff --git a/libc/src/__support/common.h b/libc/src/__support/common.h
index b5cd66ae52ca9..53a63fc2e9173 100644
--- a/libc/src/__support/common.h
+++ b/libc/src/__support/common.h
@@ -24,9 +24,9 @@
   LLVM_LIBC_FUNCTION_ATTR decltype(__llvm_libc::name)                          \
       __##name##_impl__ __asm__(#name);                                        \
   decltype(__llvm_libc::name) name [[gnu::alias(#name)]];                      \
-  type __##name##_impl__ arglist noexcept
+  type __##name##_impl__ arglist
 #else
-#define LLVM_LIBC_FUNCTION(type, name, arglist) type name arglist noexcept
+#define LLVM_LIBC_FUNCTION(type, name, arglist) type name arglist
 #endif
 
 namespace __llvm_libc {
diff --git a/libc/src/ctype/isalpha.h b/libc/src/ctype/isalpha.h
index c1f1f9e9ed054..d5697a39e9aa5 100644
--- a/libc/src/ctype/isalpha.h
+++ b/libc/src/ctype/isalpha.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int isalpha(int c) noexcept;
+int isalpha(int c);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/ctype/isascii.h b/libc/src/ctype/isascii.h
index ce328f2a2467e..7e31b3c6ca4dd 100644
--- a/libc/src/ctype/isascii.h
+++ b/libc/src/ctype/isascii.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-int isascii(int c) noexcept;
+int isascii(int c);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/ctype/isblank.h b/libc/src/ctype/isblank.h
index ac706d60588f9..0554322d08251 100644
--- a/libc/src/ctype/isblank.h
+++ b/libc/src/ctype/isblank.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int isblank(int c) noexcept;
+int isblank(int c);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/ctype/iscntrl.h b/libc/src/ctype/iscntrl.h
index 676123e269d47..26f094053a28a 100644
--- a/libc/src/ctype/iscntrl.h
+++ b/libc/src/ctype/iscntrl.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int iscntrl(int c) noexcept;
+int iscntrl(int c);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/ctype/isdigit.h b/libc/src/ctype/isdigit.h
index a0d1aa4d8181b..32a76235e0592 100644
--- a/libc/src/ctype/isdigit.h
+++ b/libc/src/ctype/isdigit.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int isdigit(int c) noexcept;
+int isdigit(int c);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/ctype/isgraph.h b/libc/src/ctype/isgraph.h
index 9eb47aa3d9372..421d0ffc4488b 100644
--- a/libc/src/ctype/isgraph.h
+++ b/libc/src/ctype/isgraph.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int isgraph(int c) noexcept;
+int isgraph(int c);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/ctype/islower.h b/libc/src/ctype/islower.h
index 7905506ad05cc..7643542fb7a99 100644
--- a/libc/src/ctype/islower.h
+++ b/libc/src/ctype/islower.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int islower(int c) noexcept;
+int islower(int c);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/ctype/isprint.h b/libc/src/ctype/isprint.h
index 97daf4b908b1d..17ed56ef25340 100644
--- a/libc/src/ctype/isprint.h
+++ b/libc/src/ctype/isprint.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int isprint(int c) noexcept;
+int isprint(int c);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/ctype/ispunct.h b/libc/src/ctype/ispunct.h
index 265524d65711b..23cc08a0bac9c 100644
--- a/libc/src/ctype/ispunct.h
+++ b/libc/src/ctype/ispunct.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int ispunct(int c) noexcept;
+int ispunct(int c);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/ctype/isspace.h b/libc/src/ctype/isspace.h
index ef49dea7462df..d919e9e7d972b 100644
--- a/libc/src/ctype/isspace.h
+++ b/libc/src/ctype/isspace.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int isspace(int c) noexcept;
+int isspace(int c);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/ctype/isupper.h b/libc/src/ctype/isupper.h
index 83a9df3044c57..7a1f2270943a9 100644
--- a/libc/src/ctype/isupper.h
+++ b/libc/src/ctype/isupper.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int isupper(int c) noexcept;
+int isupper(int c);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/ctype/isxdigit.h b/libc/src/ctype/isxdigit.h
index 16a12c1afdd42..a332ecc1018ff 100644
--- a/libc/src/ctype/isxdigit.h
+++ b/libc/src/ctype/isxdigit.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int isxdigit(int c) noexcept;
+int isxdigit(int c);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/ctype/toascii.h b/libc/src/ctype/toascii.h
index 59bac6770b844..c3f48a38d84c9 100644
--- a/libc/src/ctype/toascii.h
+++ b/libc/src/ctype/toascii.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int toascii(int c) noexcept;
+int toascii(int c);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/ctype/tolower.h b/libc/src/ctype/tolower.h
index d88be0e6f9551..97e675c558252 100644
--- a/libc/src/ctype/tolower.h
+++ b/libc/src/ctype/tolower.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int tolower(int c) noexcept;
+int tolower(int c);
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/ctype/toupper.h b/libc/src/ctype/toupper.h
index eac891d4d5949..a21b0cf79d955 100644
--- a/libc/src/ctype/toupper.h
+++ b/libc/src/ctype/toupper.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-int toupper(int c) noexcept;
+int toupper(int c);
 
 } // namespace __llvm_libc
 

From d1c9efd4c442c03364015e6503895192e4cd5b4c Mon Sep 17 00:00:00 2001
From: Alfonso Gregory <83477269+gAlfonso-bit@users.noreply.github.com>
Date: Mon, 26 Jul 2021 13:34:18 -0400
Subject: [PATCH 15/17] Revert "Update memchr.h"

This reverts commit dbc6ac1e9b10131092a426413e2034782d8cd9b0.
---
 libc/src/string/memchr.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libc/src/string/memchr.h b/libc/src/string/memchr.h
index 98246cb4ea032..369475305236d 100644
--- a/libc/src/string/memchr.h
+++ b/libc/src/string/memchr.h
@@ -13,7 +13,7 @@
 
 namespace __llvm_libc {
 
-void *memchr(const void *src, int c, size_t n) noexcept;
+void *memchr(const void *src, int c, size_t n);
 
 } // namespace __llvm_libc
 

From 165785068daad11652cc7f8394e352b4c1adc658 Mon Sep 17 00:00:00 2001
From: Alfonso Gregory <83477269+gAlfonso-bit@users.noreply.github.com>
Date: Mon, 26 Jul 2021 13:47:12 -0400
Subject: [PATCH 16/17] Fix

---
 libc/src/stdlib/abort.h     |  2 +-
 libc/src/string/memmove.cpp |  2 +-
 libc/utils/HdrGen/Command.h |  2 +-
 llvm/lib/TableGen/Error.cpp | 10 ++++------
 4 files changed, 7 insertions(+), 9 deletions(-)

diff --git a/libc/src/stdlib/abort.h b/libc/src/stdlib/abort.h
index 17f9544816632..4878fb9bbb45d 100644
--- a/libc/src/stdlib/abort.h
+++ b/libc/src/stdlib/abort.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-[[noreturn]] void abort();
+LLVM_ATTRIBUTE_NORETURN void abort();
 
 } // namespace __llvm_libc
 
diff --git a/libc/src/string/memmove.cpp b/libc/src/string/memmove.cpp
index 3e5b493e0f7f2..ebbe4643e7da6 100644
--- a/libc/src/string/memmove.cpp
+++ b/libc/src/string/memmove.cpp
@@ -16,7 +16,7 @@
 namespace __llvm_libc {
 
 static inline void move_byte_forward(char *dest_m, const char *src_m,
-                                     size_t count) noexcept {
+                                     size_t count) {
   for (size_t offset = 0; count; --count, ++offset)
     dest_m[offset] = src_m[offset];
 }
diff --git a/libc/utils/HdrGen/Command.h b/libc/utils/HdrGen/Command.h
index edc40298d97d9..4303a2204d156 100644
--- a/libc/utils/HdrGen/Command.h
+++ b/libc/utils/HdrGen/Command.h
@@ -36,7 +36,7 @@ class Command {
   public:
     ErrorReporter(llvm::SMLoc L, llvm::SourceMgr &SM) : Loc(L), SrcMgr(SM) {}
 
-    void printFatalError(llvm::Twine Msg) const {
+    LLVM_ATTRIBUTE_NORETURN void printFatalError(llvm::Twine Msg) const {
       SrcMgr.PrintMessage(Loc, llvm::SourceMgr::DK_Error, Msg);
       std::exit(1);
     }
diff --git a/llvm/lib/TableGen/Error.cpp b/llvm/lib/TableGen/Error.cpp
index 6104573b4b25b..ccec8992db54c 100644
--- a/llvm/lib/TableGen/Error.cpp
+++ b/llvm/lib/TableGen/Error.cpp
@@ -11,11 +11,11 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "llvm/TableGen/Error.h"
 #include "llvm/ADT/Twine.h"
-#include "llvm/Support/raw_ostream.h"
 #include "llvm/Support/Signals.h"
 #include "llvm/Support/WithColor.h"
-#include "llvm/TableGen/Error.h"
+#include "llvm/Support/raw_ostream.h"
 #include "llvm/TableGen/Record.h"
 #include <cstdlib>
 
@@ -42,9 +42,7 @@ static void PrintMessage(ArrayRef<SMLoc> Loc, SourceMgr::DiagKind Kind,
 
 // Functions to print notes.
 
-void PrintNote(const Twine &Msg) {
-  WithColor::note() << Msg << "\n";
-}
+void PrintNote(const Twine &Msg) { WithColor::note() << Msg << "\n"; }
 
 void PrintNote(ArrayRef<SMLoc> NoteLoc, const Twine &Msg) {
   PrintMessage(NoteLoc, SourceMgr::DK_Note, Msg);
@@ -158,7 +156,7 @@ void PrintFatalError(const RecordVal *RecVal, const Twine &Msg) {
 // If not, print a nonfatal error along with the message.
 void CheckAssert(SMLoc Loc, Init *Condition, Init *Message) {
   auto *CondValue = dyn_cast_or_null<IntInit>(
-                        Condition->convertInitializerTo(IntRecTy::get()));
+      Condition->convertInitializerTo(IntRecTy::get()));
   if (!CondValue)
     PrintError(Loc, "assert condition must of type bit, bits, or int.");
   else if (!CondValue->getValue()) {

From 4b3cb0e385e23be8878f30d506fe73ee381c7a78 Mon Sep 17 00:00:00 2001
From: Alfonso Gregory <83477269+gAlfonso-bit@users.noreply.github.com>
Date: Mon, 26 Jul 2021 13:55:11 -0400
Subject: [PATCH 17/17] Fixup

---
 libc/src/__support/integer_operations.h | 3 ++-
 libc/src/assert/__assert_fail.cpp       | 8 ++++----
 libc/src/stdlib/abort.h                 | 2 +-
 libc/utils/HdrGen/Command.h             | 2 +-
 4 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/libc/src/__support/integer_operations.h b/libc/src/__support/integer_operations.h
index f52c11a4a97e7..4c13bb86e2d87 100644
--- a/libc/src/__support/integer_operations.h
+++ b/libc/src/__support/integer_operations.h
@@ -14,7 +14,8 @@
 namespace __llvm_libc {
 
 template <typename T>
-static constexpr inline cpp::EnableIfType<cpp::IsIntegral<T>::Value, T> integerAbs(T n) {
+static constexpr cpp::EnableIfType<cpp::IsIntegral<T>::Value, T>
+integerAbs(T n) {
   return (n < 0) ? -n : n;
 }
 
diff --git a/libc/src/assert/__assert_fail.cpp b/libc/src/assert/__assert_fail.cpp
index 5ccb96dc4af47..8bb76cd430d2e 100644
--- a/libc/src/assert/__assert_fail.cpp
+++ b/libc/src/assert/__assert_fail.cpp
@@ -18,16 +18,16 @@ namespace __llvm_libc {
 // This is just a temporary solution to make assert available to internal
 // llvm libc code. In the future writeToStderr will not exist and __assert_fail
 // will call fprintf(stderr, ...).
-static void writeToStderr(const char *s) noexcept {
+static void writeToStderr(const char *s) {
   size_t length = 0;
   for (const char *curr = s; *curr; ++curr)
     ++length;
   __llvm_libc::syscall(SYS_write, 2, s, length);
 }
 
-[[noreturn]] LLVM_LIBC_FUNCTION(void, __assert_fail,
-                                (const char *assertion, const char *file,
-                                 unsigned line, const char *function)) {
+LLVM_LIBC_FUNCTION(void, __assert_fail,
+                   (const char *assertion, const char *file, unsigned line,
+                    const char *function)) {
   writeToStderr(file);
   writeToStderr(": Assertion failed: '");
   writeToStderr(assertion);
diff --git a/libc/src/stdlib/abort.h b/libc/src/stdlib/abort.h
index 4878fb9bbb45d..17f9544816632 100644
--- a/libc/src/stdlib/abort.h
+++ b/libc/src/stdlib/abort.h
@@ -11,7 +11,7 @@
 
 namespace __llvm_libc {
 
-LLVM_ATTRIBUTE_NORETURN void abort();
+[[noreturn]] void abort();
 
 } // namespace __llvm_libc
 
diff --git a/libc/utils/HdrGen/Command.h b/libc/utils/HdrGen/Command.h
index 4303a2204d156..895f472c3ad32 100644
--- a/libc/utils/HdrGen/Command.h
+++ b/libc/utils/HdrGen/Command.h
@@ -36,7 +36,7 @@ class Command {
   public:
     ErrorReporter(llvm::SMLoc L, llvm::SourceMgr &SM) : Loc(L), SrcMgr(SM) {}
 
-    LLVM_ATTRIBUTE_NORETURN void printFatalError(llvm::Twine Msg) const {
+    [[noreturn]] void printFatalError(llvm::Twine Msg) const {
       SrcMgr.PrintMessage(Loc, llvm::SourceMgr::DK_Error, Msg);
       std::exit(1);
     }