Rollup merge of #140521 - RalfJung:oob-error, r=saethlin

interpret: better error message for out-of-bounds pointer arithmetic and accesses

Fixes #93881
r? `@saethlin`

Author: matthiaskrgr

compiler/rustc_const_eval/messages.ftl

@@ -12,6 +12,27 @@ const_eval_already_reported =
 const_eval_assume_false =
     `assume` called with `false`
 
+const_eval_bad_pointer_op = {$operation ->
+  [MemoryAccess] memory access failed
+  [InboundsPointerArithmetic] in-bounds pointer arithmetic failed
+  *[Dereferenceable] pointer not dereferenceable
+}
+const_eval_bad_pointer_op_attempting = {const_eval_bad_pointer_op}: {$operation ->
+    [MemoryAccess] attempting to access {$inbounds_size ->
+            [1] 1 byte
+            *[x] {$inbounds_size} bytes
+        }
+    [InboundsPointerArithmetic] attempting to offset pointer by {$inbounds_size ->
+            [1] 1 byte
+            *[x] {$inbounds_size} bytes
+        }
+    *[Dereferenceable] pointer must {$inbounds_size ->
+            [0] point to some allocation
+            [1] be dereferenceable for 1 byte
+            *[x] be dereferenceable for {$inbounds_size} bytes
+        }
+    }
+
 const_eval_bounds_check_failed =
     indexing out of bounds: the len is {$len} but the index is {$index}
 const_eval_call_nonzero_intrinsic =
@@ -39,9 +60,9 @@ const_eval_copy_nonoverlapping_overlapping =
     `copy_nonoverlapping` called on overlapping ranges
 
 const_eval_dangling_int_pointer =
-    {$bad_pointer_message}: {const_eval_expected_inbounds_pointer}, but got {$pointer} which is a dangling pointer (it has no provenance)
+    {const_eval_bad_pointer_op_attempting}, but got {$pointer} which is a dangling pointer (it has no provenance)
 const_eval_dangling_null_pointer =
-    {$bad_pointer_message}: {const_eval_expected_inbounds_pointer}, but got a null pointer
+    {const_eval_bad_pointer_op_attempting}, but got null pointer
 
 const_eval_dangling_ptr_in_final = encountered dangling pointer in final value of {const_eval_intern_kind}
 const_eval_dead_local =
@@ -77,21 +98,6 @@ const_eval_error = {$error_kind ->
 const_eval_exact_div_has_remainder =
     exact_div: {$a} cannot be divided by {$b} without remainder
 
-const_eval_expected_inbounds_pointer =
-    expected a pointer to {$inbounds_size_abs ->
-        [0] some allocation
-        *[x] {$inbounds_size_is_neg ->
-            [false] {$inbounds_size_abs ->
-                    [1] 1 byte of memory
-                    *[x] {$inbounds_size_abs} bytes of memory
-                }
-            *[true] the end of {$inbounds_size_abs ->
-                    [1] 1 byte of memory
-                    *[x] {$inbounds_size_abs} bytes of memory
-                }
-        }
-    }
-
 const_eval_extern_static =
     cannot access extern static `{$did}`
 const_eval_extern_type_field = `extern type` field does not have a known offset
@@ -111,7 +117,6 @@ const_eval_frame_note_inner = inside {$where_ ->
 
 const_eval_frame_note_last = the failure occurred here
 
-const_eval_in_bounds_test = out-of-bounds pointer use
 const_eval_incompatible_calling_conventions =
     calling a function with calling convention {$callee_conv} using calling convention {$caller_conv}
 
@@ -206,7 +211,6 @@ const_eval_long_running =
 
 const_eval_max_num_nodes_in_const = maximum number of nodes exceeded in constant {$global_const_id}
 
-const_eval_memory_access_test = memory access failed
 const_eval_memory_exhausted =
     tried to allocate more memory than available to compiler
 
@@ -287,8 +291,6 @@ const_eval_offset_from_out_of_bounds =
     `{$name}` called on two different pointers where the memory range between them is not in-bounds of an allocation
 const_eval_offset_from_overflow =
     `{$name}` called when first pointer is too far ahead of second
-const_eval_offset_from_test =
-    out-of-bounds `offset_from` origin
 const_eval_offset_from_underflow =
     `{$name}` called when first pointer is too far before second
 const_eval_offset_from_unsigned_overflow =
@@ -312,27 +314,25 @@ const_eval_partial_pointer_overwrite =
     unable to overwrite parts of a pointer in memory at {$ptr}
 const_eval_pointer_arithmetic_overflow =
     overflowing pointer arithmetic: the total offset in bytes does not fit in an `isize`
-const_eval_pointer_arithmetic_test = out-of-bounds pointer arithmetic
+
 const_eval_pointer_out_of_bounds =
-    {$bad_pointer_message}: {const_eval_expected_inbounds_pointer}, but got {$pointer} {$ptr_offset_is_neg ->
-        [true] which points to before the beginning of the allocation
-        *[false] {$inbounds_size_is_neg ->
-            [true] {$ptr_offset_abs ->
-                [0] which is at the beginning of the allocation
-                *[other] which does not have enough space to the beginning of the allocation
-            }
-            *[false] {$alloc_size_minus_ptr_offset ->
-                [0] which is at or beyond the end of the allocation of size {$alloc_size ->
+    {const_eval_bad_pointer_op_attempting}, but got {$pointer} which {$inbounds_size_is_neg ->
+        [false] {$alloc_size_minus_ptr_offset ->
+                [0] is at or beyond the end of the allocation of size {$alloc_size ->
                     [1] 1 byte
                     *[x] {$alloc_size} bytes
                 }
-                [1] which is only 1 byte from the end of the allocation
-                *[x] which is only {$alloc_size_minus_ptr_offset} bytes from the end of the allocation
+                [1] is only 1 byte from the end of the allocation
+                *[x] is only {$alloc_size_minus_ptr_offset} bytes from the end of the allocation
+            }
+        *[true] {$ptr_offset_abs ->
+                [0] is at the beginning of the allocation
+                *[other] is only {$ptr_offset_abs} bytes from the beginning of the allocation
             }
-        }
     }
+
 const_eval_pointer_use_after_free =
-    {$bad_pointer_message}: {$alloc_id} has been freed, so this pointer is dangling
+    {const_eval_bad_pointer_op}: {$alloc_id} has been freed, so this pointer is dangling
 const_eval_ptr_as_bytes_1 =
     this code performed an operation that depends on the underlying bytes representing a pointer
 const_eval_ptr_as_bytes_2 =

compiler/rustc_const_eval/src/errors.rs

@@ -5,15 +5,14 @@ use either::Either;
 use rustc_abi::WrappingRange;
 use rustc_errors::codes::*;
 use rustc_errors::{
-    Diag, DiagArgValue, DiagCtxtHandle, DiagMessage, Diagnostic, EmissionGuarantee, Level,
-    MultiSpan, Subdiagnostic,
+    Diag, DiagArgValue, DiagMessage, Diagnostic, EmissionGuarantee, Level, MultiSpan, Subdiagnostic,
 };
 use rustc_hir::ConstContext;
 use rustc_macros::{Diagnostic, LintDiagnostic, Subdiagnostic};
 use rustc_middle::mir::interpret::{
-    CheckInAllocMsg, CtfeProvenance, ExpectedKind, InterpErrorKind, InvalidMetaKind,
-    InvalidProgramInfo, Misalignment, Pointer, PointerKind, ResourceExhaustionInfo,
-    UndefinedBehaviorInfo, UnsupportedOpInfo, ValidationErrorInfo,
+    CtfeProvenance, ExpectedKind, InterpErrorKind, InvalidMetaKind, InvalidProgramInfo,
+    Misalignment, Pointer, PointerKind, ResourceExhaustionInfo, UndefinedBehaviorInfo,
+    UnsupportedOpInfo, ValidationErrorInfo,
 };
 use rustc_middle::ty::{self, Mutability, Ty};
 use rustc_span::{Span, Symbol};
@@ -498,19 +497,6 @@ pub trait ReportErrorExt {
     }
 }
 
-fn bad_pointer_message(msg: CheckInAllocMsg, dcx: DiagCtxtHandle<'_>) -> String {
-    use crate::fluent_generated::*;
-
-    let msg = match msg {
-        CheckInAllocMsg::MemoryAccessTest => const_eval_memory_access_test,
-        CheckInAllocMsg::PointerArithmeticTest => const_eval_pointer_arithmetic_test,
-        CheckInAllocMsg::OffsetFromTest => const_eval_offset_from_test,
-        CheckInAllocMsg::InboundsTest => const_eval_in_bounds_test,
-    };
-
-    dcx.eagerly_translate_to_string(msg, [].into_iter())
-}
-
 impl<'a> ReportErrorExt for UndefinedBehaviorInfo<'a> {
     fn diagnostic_message(&self) -> DiagMessage {
         use UndefinedBehaviorInfo::*;
@@ -564,7 +550,6 @@ impl<'a> ReportErrorExt for UndefinedBehaviorInfo<'a> {
 
     fn add_args<G: EmissionGuarantee>(self, diag: &mut Diag<'_, G>) {
         use UndefinedBehaviorInfo::*;
-        let dcx = diag.dcx;
         match self {
             Ub(_) => {}
             Custom(custom) => {
@@ -612,12 +597,10 @@ impl<'a> ReportErrorExt for UndefinedBehaviorInfo<'a> {
                 diag.arg("vtable_dyn_type", vtable_dyn_type.to_string());
             }
             PointerUseAfterFree(alloc_id, msg) => {
-                diag.arg("alloc_id", alloc_id)
-                    .arg("bad_pointer_message", bad_pointer_message(msg, dcx));
+                diag.arg("alloc_id", alloc_id).arg("operation", format!("{:?}", msg));
             }
             PointerOutOfBounds { alloc_id, alloc_size, ptr_offset, inbounds_size, msg } => {
                 diag.arg("alloc_size", alloc_size.bytes());
-                diag.arg("bad_pointer_message", bad_pointer_message(msg, dcx));
                 diag.arg("pointer", {
                     let mut out = format!("{:?}", alloc_id);
                     if ptr_offset > 0 {
@@ -627,14 +610,17 @@ impl<'a> ReportErrorExt for UndefinedBehaviorInfo<'a> {
                     }
                     out
                 });
+                diag.arg("inbounds_size", inbounds_size);
                 diag.arg("inbounds_size_is_neg", inbounds_size < 0);
                 diag.arg("inbounds_size_abs", inbounds_size.unsigned_abs());
+                diag.arg("ptr_offset", ptr_offset);
                 diag.arg("ptr_offset_is_neg", ptr_offset < 0);
                 diag.arg("ptr_offset_abs", ptr_offset.unsigned_abs());
                 diag.arg(
                     "alloc_size_minus_ptr_offset",
                     alloc_size.bytes().saturating_sub(ptr_offset as u64),
                 );
+                diag.arg("operation", format!("{:?}", msg));
             }
             DanglingIntPointer { addr, inbounds_size, msg } => {
                 if addr != 0 {
@@ -644,9 +630,10 @@ impl<'a> ReportErrorExt for UndefinedBehaviorInfo<'a> {
                     );
                 }
 
+                diag.arg("inbounds_size", inbounds_size);
                 diag.arg("inbounds_size_is_neg", inbounds_size < 0);
                 diag.arg("inbounds_size_abs", inbounds_size.unsigned_abs());
-                diag.arg("bad_pointer_message", bad_pointer_message(msg, dcx));
+                diag.arg("operation", format!("{:?}", msg));
             }
             AlignmentCheckFailed(Misalignment { required, has }, msg) => {
                 diag.arg("required", required.bytes());