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

[Roland McGrath via llvm-commits]

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@@ -16,4 +19,13 @@ void die(const char *Message) {
   __sanitizer_log_write(Message, strlen(Message));
   __builtin_trap();
 }
+
+void dieWithErrorCode(const char *Message, int64_t ErrorCode) {
+  size_t buffer_size = strlen(Message) + 48;
+  char *buffer = static_cast<char *>(alloca(buffer_size));
+  snprintf(buffer, buffer_size, "%s (Error Code: %" PRId64 ")", Message,
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frobtech wrote:

This could use `zx_status_get_string(static_cast<zx_status_t>(ErrorCode))` to yield a canonical string instead of just the number, but the number is fine too.  (Note that this is the `ZX_ERR_FOO` name, equivalent to the POSIX `EFOO` name as used in C programs, not the human-readable text like `strerror`).


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