[compiler-rt] Log errno (or fuchsia equivalent) on map failures (PR #95391)

[Vitaly Buka via llvm-commits]

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@@ -12,17 +12,28 @@
 #include "gwp_asan/definitions.h"
 
 #include <stddef.h>
+#include <stdint.h>
 
 namespace gwp_asan {
 // Terminates in a platform-specific way with `Message`.
 void die(const char *Message);
+void dieWithErrorCode(const char *Message, int64_t ErrorCode);
 
 // Checks that `Condition` is true, otherwise dies with `Message`.
-GWP_ASAN_ALWAYS_INLINE void Check(bool Condition, const char *Message) {
+GWP_ASAN_ALWAYS_INLINE void check(bool Condition, const char *Message) {
   if (Condition)
     return;
   die(Message);
 }
+
+// Checks that `Condition` is true, otherwise dies with `Message` (including
+// errno at the end).
+GWP_ASAN_ALWAYS_INLINE void
+checkWithErrorCode(bool Condition, const char *Message, int64_t ErrorCode) {
+  if (Condition)
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vitalybuka wrote:

you may want `LIKELY` annotation
it makes noticable perf difference on hot code.


https://github.com/llvm/llvm-project/pull/95391