Update libcxxabi to llvm-12 (#14288)

Followup to #14280

Changes from upstream can be seen at:
llvm/llvm-project@llvmorg-12.0.0...emscripten-core:emscripten-libs-12.0.0

Fixes: #14244

Author: sbc100

ChangeLog.md

@@ -20,6 +20,7 @@ See docs/process.md for more on how version tagging works.
 
 2.0.23
 ------
+- libcxxabi updated to llvm-12. (#14288)
 - libcxx updated to llvm-12. (#14249)
 - compiler-rt updated to llvm-12. (#14280)
 

system/lib/libcxxabi/include/__cxxabi_config.h

@@ -18,6 +18,19 @@
 #define __has_attribute(_attribute_) 0
 #endif
 
+#if defined(__clang__)
+#  define _LIBCXXABI_COMPILER_CLANG
+#  ifndef __apple_build_version__
+#    define _LIBCXXABI_CLANG_VER (__clang_major__ * 100 + __clang_minor__)
+#  endif
+#elif defined(__GNUC__)
+#  define _LIBCXXABI_COMPILER_GCC
+#elif defined(_MSC_VER)
+#  define _LIBCXXABI_COMPILER_MSVC
+#elif defined(__IBMCPP__)
+#  define _LIBCXXABI_COMPILER_IBM
+#endif
+
 #if defined(_WIN32)
  #if defined(_LIBCXXABI_DISABLE_VISIBILITY_ANNOTATIONS)
   #define _LIBCXXABI_HIDDEN
@@ -53,7 +66,7 @@
  #endif
 #endif
 
-#if defined(_WIN32)
+#if defined(_LIBCXXABI_COMPILER_MSVC)
 #define _LIBCXXABI_WEAK
 #else
 #define _LIBCXXABI_WEAK __attribute__((__weak__))
@@ -72,8 +85,16 @@
 #endif
 
 // wasm32 follows the arm32 ABI convention of using 32-bit guard.
-#if defined(__arm__) || defined(__wasm32__)
+#if defined(__arm__) || defined(__wasm32__) || defined(__ARM64_ARCH_8_32__)
 #  define _LIBCXXABI_GUARD_ABI_ARM
 #endif
 
+#if defined(_LIBCXXABI_COMPILER_CLANG)
+#  if !__has_feature(cxx_exceptions)
+#    define _LIBCXXABI_NO_EXCEPTIONS
+#  endif
+#elif defined(_LIBCXXABI_COMPILER_GCC) && !__EXCEPTIONS
+#  define _LIBCXXABI_NO_EXCEPTIONS
+#endif
+
 #endif // ____CXXABI_CONFIG_H

system/lib/libcxxabi/include/cxxabi.h

@@ -21,6 +21,7 @@
 
 #define _LIBCPPABI_VERSION 1002
 #define _LIBCXXABI_NORETURN  __attribute__((noreturn))
+#define _LIBCXXABI_ALWAYS_COLD __attribute__((cold))
 
 #ifdef __cplusplus
 
@@ -82,13 +83,13 @@ extern _LIBCXXABI_FUNC_VIS _LIBCXXABI_NORETURN void __cxa_deleted_virtual(void);
 
 // 3.3.2 One-time Construction API
 #if defined(_LIBCXXABI_GUARD_ABI_ARM)
-extern _LIBCXXABI_FUNC_VIS int __cxa_guard_acquire(uint32_t *);
-extern _LIBCXXABI_FUNC_VIS void __cxa_guard_release(uint32_t *);
-extern _LIBCXXABI_FUNC_VIS void __cxa_guard_abort(uint32_t *);
+extern _LIBCXXABI_FUNC_VIS _LIBCXXABI_ALWAYS_COLD int __cxa_guard_acquire(uint32_t *);
+extern _LIBCXXABI_FUNC_VIS _LIBCXXABI_ALWAYS_COLD void __cxa_guard_release(uint32_t *);
+extern _LIBCXXABI_FUNC_VIS _LIBCXXABI_ALWAYS_COLD void __cxa_guard_abort(uint32_t *);
 #else
-extern _LIBCXXABI_FUNC_VIS int __cxa_guard_acquire(uint64_t *);
-extern _LIBCXXABI_FUNC_VIS void __cxa_guard_release(uint64_t *);
-extern _LIBCXXABI_FUNC_VIS void __cxa_guard_abort(uint64_t *);
+extern _LIBCXXABI_FUNC_VIS _LIBCXXABI_ALWAYS_COLD int __cxa_guard_acquire(uint64_t *);
+extern _LIBCXXABI_FUNC_VIS _LIBCXXABI_ALWAYS_COLD void __cxa_guard_release(uint64_t *);
+extern _LIBCXXABI_FUNC_VIS _LIBCXXABI_ALWAYS_COLD void __cxa_guard_abort(uint64_t *);
 #endif
 
 // 3.3.3 Array Construction and Destruction API
@@ -140,9 +141,9 @@ __cxa_vec_cctor(void *dest_array, void *src_array, size_t element_count,
                 void (*destructor)(void *));
 
 // 3.3.5.3 Runtime API
-extern _LIBCXXABI_FUNC_VIS int __cxa_atexit(void (*f)(void *), void *p,
-                                            void *d);
-extern _LIBCXXABI_FUNC_VIS int __cxa_finalize(void *);
+// These functions are part of the C++ ABI, but they are not defined in libc++abi:
+//    int __cxa_atexit(void (*)(void *), void *, void *);
+//    void __cxa_finalize(void *);
 
 // 3.4 Demangler API
 extern _LIBCXXABI_FUNC_VIS char *__cxa_demangle(const char *mangled_name,

system/lib/libcxxabi/readme.txt

@@ -1,7 +1,7 @@
 llvm's libcxxabi
 ----------------
 
-These files are from the llvm-project based on release 10.0.0.
+These files are from the llvm-project based on release 12.0.0.
 
 We maintain a local fork of llvm-project that contains any emscripten
 specific patches:
@@ -10,8 +10,8 @@ specific patches:
 
 The current patch is based on:
 
-tag: llvmorg-10.0.0
-git: d32170dbd5b0d54436537b6b75beaf44324e0c28
+tag: llvmorg-12.0.0
+git: d28af7c654d8db0b68c175db5ce212d74fb5e9bc
 
 Update Instructions
 -------------------

system/lib/libcxxabi/src/CMakeLists.txt

@@ -7,7 +7,6 @@ set(LIBCXXABI_SOURCES
   cxa_exception_storage.cpp
   cxa_guard.cpp
   cxa_handlers.cpp
-  cxa_unexpected.cpp
   cxa_vector.cpp
   cxa_virtual.cpp
   # C++ STL files
@@ -21,7 +20,9 @@ set(LIBCXXABI_SOURCES
 )
 
 if (LIBCXXABI_ENABLE_NEW_DELETE_DEFINITIONS)
-  list(APPEND LIBCXXABI_SOURCES stdlib_new_delete.cpp)
+  list(APPEND LIBCXXABI_SOURCES
+    stdlib_new_delete.cpp
+  )
 endif()
 
 if (LIBCXXABI_ENABLE_EXCEPTIONS)
@@ -60,6 +61,10 @@ if (LIBCXXABI_HAS_CXA_THREAD_ATEXIT_IMPL)
   add_definitions(-DHAVE___CXA_THREAD_ATEXIT_IMPL)
 endif()
 
+if (LIBCXXABI_ENABLE_FORGIVING_DYNAMIC_CAST)
+  add_definitions(-D_LIBCXXABI_FORGIVING_DYNAMIC_CAST)
+endif()
+
 if (APPLE)
   add_library_flags_if(LIBCXXABI_HAS_SYSTEM_LIB System)
 else()
@@ -95,6 +100,9 @@ if (MINGW)
   # MINGW_LIBRARIES is defined in config-ix.cmake
   list(APPEND LIBCXXABI_LIBRARIES ${MINGW_LIBRARIES})
 endif()
+if (ANDROID AND ANDROID_PLATFORM_LEVEL LESS 21)
+  list(APPEND LIBCXXABI_LIBRARIES android_support)
+endif()
 
 if (NOT LIBCXXABI_USE_COMPILER_RT)
   add_library_flags_if(LIBCXXABI_HAS_GCC_LIB gcc)
@@ -128,6 +136,17 @@ if ( APPLE )
       add_link_flags("-Wl,-rpath,${LIBDIR}")
     endif()
   endif()
+
+  # Make sure we link in CrashReporterClient if we find it -- it's used by
+  # abort() on Apple platforms when building the system dylib.
+  find_library(CrashReporterClient NAMES libCrashReporterClient.a
+                                   PATHS "${CMAKE_OSX_SYSROOT}/usr/local/lib")
+  if (CrashReporterClient)
+    message(STATUS "Linking with CrashReporterClient at ${CrashReporterClient}")
+    add_library_flags("${CrashReporterClient}")
+  else()
+    message(STATUS "Could not find CrashReporterClient, not linking against it")
+  endif()
 endif()
 
 split_list(LIBCXXABI_COMPILE_FLAGS)
@@ -143,18 +162,9 @@ if (NOT TARGET pstl::ParallelSTL)
   message(STATUS "Could not find ParallelSTL, libc++abi will not attempt to use it but the build may fail if the libc++ in use needs it to be available.")
 endif()
 
-if ("${CMAKE_OSX_ARCHITECTURES}" MATCHES "^(armv6|armv7|armv7s)$")
-  set(LIBCXXABI_USE_SJLJ_EXCEPTIONS ON)
-else()
-  set(LIBCXXABI_USE_SJLJ_EXCEPTIONS OFF)
-endif()
-
 # Build the shared library.
 if (LIBCXXABI_ENABLE_SHARED)
   add_library(cxxabi_shared SHARED ${LIBCXXABI_SOURCES} ${LIBCXXABI_HEADERS})
-  if(COMMAND llvm_setup_rpath)
-    llvm_setup_rpath(cxxabi_shared)
-  endif()
   target_link_libraries(cxxabi_shared PRIVATE ${LIBCXXABI_SHARED_LIBRARIES} ${LIBCXXABI_LIBRARIES})
   if (TARGET pstl::ParallelSTL)
     target_link_libraries(cxxabi_shared PUBLIC pstl::ParallelSTL)
@@ -164,9 +174,9 @@ if (LIBCXXABI_ENABLE_SHARED)
                           CXX_EXTENSIONS
                             OFF
                           CXX_STANDARD
-                            11
+                            20
                           CXX_STANDARD_REQUIRED
-                            ON
+                            OFF
                           COMPILE_FLAGS
                             "${LIBCXXABI_COMPILE_FLAGS}"
                           LINK_FLAGS
@@ -189,18 +199,32 @@ if (LIBCXXABI_ENABLE_SHARED)
     list(APPEND LIBCXXABI_INSTALL_TARGETS "cxxabi_shared")
   endif()
 
+  add_library(cxxabi-reexports INTERFACE)
+
   # -exported_symbols_list is only available on Apple platforms
   if (APPLE)
-    target_link_libraries(cxxabi_shared PRIVATE "-Wl,-exported_symbols_list,${CMAKE_CURRENT_SOURCE_DIR}/../lib/itanium-base.exp")
+    function(export_symbols file)
+      target_link_libraries(cxxabi_shared PRIVATE "-Wl,-exported_symbols_list,${file}")
+    endfunction()
+    function(reexport_symbols file)
+      export_symbols("${file}")
+      target_link_libraries(cxxabi-reexports INTERFACE "-Wl,-reexported_symbols_list,${file}")
+    endfunction()
+
+    export_symbols("${CMAKE_CURRENT_SOURCE_DIR}/../lib/itanium-base.exp")
 
     if (LIBCXXABI_ENABLE_NEW_DELETE_DEFINITIONS)
-      target_link_libraries(cxxabi_shared PRIVATE "-Wl,-exported_symbols_list,${CMAKE_CURRENT_SOURCE_DIR}/../lib/new-delete.exp")
+      reexport_symbols("${CMAKE_CURRENT_SOURCE_DIR}/../lib/new-delete.exp")
     endif()
 
-    if (LIBCXXABI_USE_SJLJ_EXCEPTIONS)
-      target_link_libraries(cxxabi_shared PRIVATE "-Wl,-exported_symbols_list,${CMAKE_CURRENT_SOURCE_DIR}/../lib/personality-sjlj.exp")
-    else()
-      target_link_libraries(cxxabi_shared PRIVATE "-Wl,-exported_symbols_list,${CMAKE_CURRENT_SOURCE_DIR}/../lib/personality-v0.exp")
+    if (LIBCXXABI_ENABLE_EXCEPTIONS)
+      reexport_symbols("${CMAKE_CURRENT_SOURCE_DIR}/../lib/exceptions.exp")
+
+      if ("${CMAKE_OSX_ARCHITECTURES}" MATCHES "^(armv6|armv7|armv7s)$")
+        reexport_symbols("${CMAKE_CURRENT_SOURCE_DIR}/../lib/personality-sjlj.exp")
+      else()
+        reexport_symbols("${CMAKE_CURRENT_SOURCE_DIR}/../lib/personality-v0.exp")
+      endif()
     endif()
   endif()
 endif()
@@ -217,9 +241,9 @@ if (LIBCXXABI_ENABLE_STATIC)
                           CXX_EXTENSIONS
                             OFF
                           CXX_STANDARD
-                            11
+                            20
                           CXX_STANDARD_REQUIRED
-                            ON
+                            OFF
                           COMPILE_FLAGS
                             "${LIBCXXABI_COMPILE_FLAGS}"
                           LINK_FLAGS
@@ -255,10 +279,10 @@ if (LIBCXXABI_ENABLE_STATIC)
     set(MERGE_ARCHIVES_LIBTOOL "--use-libtool" "--libtool" "${CMAKE_LIBTOOL}")
   endif()
 
-  # Merge the the libc++abi.a and libunwind.a into one.
+  # Merge the libc++abi.a and libunwind.a into one.
   if(LIBCXXABI_USE_LLVM_UNWINDER AND LIBCXXABI_STATICALLY_LINK_UNWINDER_IN_STATIC_LIBRARY)
     add_custom_command(TARGET cxxabi_static POST_BUILD
-      COMMAND ${PYTHON_EXECUTABLE} ${LIBCXXABI_LIBCXX_PATH}/utils/merge_archives.py
+      COMMAND ${Python3_EXECUTABLE} ${LIBCXXABI_LIBCXX_PATH}/utils/merge_archives.py
       ARGS
         -o "$<TARGET_LINKER_FILE:cxxabi_static>"
         --ar "${CMAKE_AR}"
@@ -292,7 +316,4 @@ if (NOT CMAKE_CONFIGURATION_TYPES AND LIBCXXABI_INSTALL_LIBRARY)
             -DCMAKE_INSTALL_COMPONENT=cxxabi
             -DCMAKE_INSTALL_DO_STRIP=1
             -P "${LIBCXXABI_BINARY_DIR}/cmake_install.cmake")
-
-  # TODO: This is a legacy target name and should be removed at some point.
-  add_custom_target(install-libcxxabi DEPENDS install-cxxabi)
 endif()

system/lib/libcxxabi/src/abort_message.cpp

@@ -12,74 +12,76 @@
 #include "abort_message.h"
 
 #ifdef __BIONIC__
-#include <android/api-level.h>
-#if __ANDROID_API__ >= 21
-#include <syslog.h>
-extern "C" void android_set_abort_message(const char* msg);
-#else
-#include <assert.h>
-#endif // __ANDROID_API__ >= 21
+#   include <android/api-level.h>
+#   if __ANDROID_API__ >= 21
+#       include <syslog.h>
+        extern "C" void android_set_abort_message(const char* msg);
+#   else
+#       include <assert.h>
+#   endif // __ANDROID_API__ >= 21
 #endif // __BIONIC__
 
-#ifdef __APPLE__
-#   if defined(__has_include) && __has_include(<CrashReporterClient.h>)
-#       define HAVE_CRASHREPORTERCLIENT_H
-#       include <CrashReporterClient.h>
-#   endif
+#if defined(__APPLE__) && __has_include(<CrashReporterClient.h>)
+#   include <CrashReporterClient.h>
+#   define _LIBCXXABI_USE_CRASHREPORTER_CLIENT
 #endif
 
 void abort_message(const char* format, ...)
 {
-    // write message to stderr
+    // Write message to stderr. We do this before formatting into a
+    // variable-size buffer so that we still get some information if
+    // formatting into the variable-sized buffer fails.
 #if !defined(NDEBUG) || !defined(LIBCXXABI_BAREMETAL)
-#ifdef __APPLE__
-    fprintf(stderr, "libc++abi.dylib: ");
-#endif
+    {
 #if defined(__EMSCRIPTEN__) && defined(NDEBUG)
-    // Just trap in a non-debug build. These internal libcxxabi assertions are
-    // very rare, and it's not worth linking in vfprintf stdio support or
-    // even minimal logging for them, as we'll have a proper call stack, which
-    // will show a call into "abort_message", and can help debugging. (In a
-    // debug build that won't be inlined.)
-    __builtin_trap();
+        // Just trap in a non-debug build. These internal libcxxabi assertions are
+        // very rare, and it's not worth linking in vfprintf stdio support or
+        // even minimal logging for them, as we'll have a proper call stack, which
+        // will show a call into "abort_message", and can help debugging. (In a
+        // debug build that won't be inlined.)
+        __builtin_trap();
 #else
+        fprintf(stderr, "libc++abi: ");
+        va_list list;
+        va_start(list, format);
+        vfprintf(stderr, format, list);
+        va_end(list);
+        fprintf(stderr, "\n");
+#endif
+    }
+#endif
+
+    // Format the arguments into an allocated buffer. We leak the buffer on
+    // purpose, since we're about to abort() anyway.
+#if defined(_LIBCXXABI_USE_CRASHREPORTER_CLIENT)
+    char* buffer;
     va_list list;
     va_start(list, format);
-    vfprintf(stderr, format, list);
+    vasprintf(&buffer, format, list);
     va_end(list);
-    fprintf(stderr, "\n");
-#endif // EMSCRIPTEN
-#endif
 
-#if defined(__APPLE__) && defined(HAVE_CRASHREPORTERCLIENT_H)
-    // record message in crash report
-    char* buffer;
-    va_list list2;
-    va_start(list2, format);
-    vasprintf(&buffer, format, list2);
-    va_end(list2);
     CRSetCrashLogMessage(buffer);
 #elif defined(__BIONIC__)
     char* buffer;
-    va_list list2;
-    va_start(list2, format);
-    vasprintf(&buffer, format, list2);
-    va_end(list2);
+    va_list list;
+    va_start(list, format);
+    vasprintf(&buffer, format, list);
+    va_end(list);
 
-#if __ANDROID_API__ >= 21
+#   if __ANDROID_API__ >= 21
     // Show error in tombstone.
     android_set_abort_message(buffer);
 
     // Show error in logcat.
     openlog("libc++abi", 0, 0);
     syslog(LOG_CRIT, "%s", buffer);
     closelog();
-#else
+#   else
     // The good error reporting wasn't available in Android until L. Since we're
     // about to abort anyway, just call __assert2, which will log _somewhere_
     // (tombstone and/or logcat) in older releases.
     __assert2(__FILE__, __LINE__, __func__, buffer);
-#endif // __ANDROID_API__ >= 21
+#   endif // __ANDROID_API__ >= 21
 #endif // __BIONIC__
 
     abort();