[compiler-rt] Silence warnings about large stack frames in ReadBinaryName

[mstorsjo]

Summary

The disabling of the warning also needs to cover ReadLongProcessName, which ends up inlining the function and producing a separate warning about stack size.

Other cases of the same were silenced similarly in D91853.

[rnk]

I dug back to 2014 to find out why we have this flag: rG167c15a98feb898c13eca325678b73d0c59dffa2 Unfortunately, it seems there is no rationale. I'm guessing it's carried over from TSan, which has this flag. TSan uses sanitizer_common, so if tsan cares about frame size, then sanitizer_common does. The TSan warning flag comes from rG06379b35373e0ca9561c130284104fbdf0295f79, but again, no rationale or link to a review thread. =/

Instead of disabling the warning and adding ifdefs, maybe it's better to just fix the warning with InternalMmapVector<wchar_t>. The vast majority of uses of kMaxPathLength are for local InternalScopedString variables.

[mstorsjo]

In D97579#2594982, @rnk wrote:

I dug back to 2014 to find out why we have this flag: rG167c15a98feb898c13eca325678b73d0c59dffa2 Unfortunately, it seems there is no rationale. I'm guessing it's carried over from TSan, which has this flag. TSan uses sanitizer_common, so if tsan cares about frame size, then sanitizer_common does. The TSan warning flag comes from rG06379b35373e0ca9561c130284104fbdf0295f79, but again, no rationale or link to a review thread. =/

Instead of disabling the warning and adding ifdefs, maybe it's better to just fix the warning with InternalMmapVector<wchar_t>. The vast majority of uses of kMaxPathLength are for local InternalScopedString variables.

Thanks for digging in! I've added a couple similar ones before - I can undo those and use InternalMmapVector<> for those too - but I don't (yet) have a setup where I can easily run the sanitizer tests - do you happen to have that? I'll post an alternative patch with that in any case.

[mstorsjo]

Superseded by D97726.

compiler-rt/lib/sanitizer_common/sanitizer_win.cpp

     case EXCEPTION_INT_DIVIDE_BY_ZERO:
       return "int-divide-by-zero";
     case EXCEPTION_INT_OVERFLOW:
       return "int-overflow";
   }
   return "unknown exception";
 }
 
+#ifdef __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wframe-larger-than="
+#endif
 uptr ReadBinaryName(/*out*/char *buf, uptr buf_len) {
   if (buf_len == 0)
     return 0;
 
   // Get the UTF-16 path and convert to UTF-8.
   wchar_t binname_utf16[kMaxPathLength];
   int binname_utf16_len =
       GetModuleFileNameW(NULL, binname_utf16, ARRAY_SIZE(binname_utf16));
   if (binname_utf16_len == 0) {
     buf[0] = '\0';
     return 0;
   }
   int binary_name_len = ::WideCharToMultiByte(
       CP_UTF8, 0, binname_utf16, binname_utf16_len, buf, buf_len, NULL, NULL);
   if ((unsigned)binary_name_len == buf_len)
     --binary_name_len;
   buf[binary_name_len] = '\0';
   return binary_name_len;
 }
 
 uptr ReadLongProcessName(/*out*/char *buf, uptr buf_len) {
   return ReadBinaryName(buf, buf_len);
 }
+#ifdef __clang__
+#pragma clang diagnostic pop
+#endif
 
 void CheckVMASize() {
   // Do nothing.
 }
 
 void InitializePlatformEarly() {
   // Do nothing.
 }