scudo: fix __attribute__((format))

[dvyukov]

Summary

The attribute should be in the header on declaration.
It's almost pointless in the source file.

Depends on D107977.

[pcc]

Note that this is the legacy copy of Scudo. Looks like scudo/standalone has the same problem (see ScopedString::Append and Printf in compiler-rt/lib/scudo/standalone/string_utils.cpp).

[dvyukov]

In D107978#2942511, @pcc wrote:

Note that this is the legacy copy of Scudo. Looks like scudo/standalone has the same problem (see ScopedString::Append and Printf in compiler-rt/lib/scudo/standalone/string_utils.cpp).

Thanks. I've added https://reviews.llvm.org/D108014 to the series.

compiler-rt/lib/scudo/scudo_utils.h

 template <class Dest, class Source>
 inline Dest bit_cast(const Source& source) {
   static_assert(sizeof(Dest) == sizeof(Source), "Sizes are not equal!");
   Dest dest;
   memcpy(&dest, &source, sizeof(dest));
   return dest;
 }
 
-void NORETURN dieWithMessage(const char *Format, ...);
+void dieWithMessage(const char *Format, ...) NORETURN FORMAT(1, 2);
 
 bool hasHardwareCRC32();
 
 }  // namespace __scudo
 
 #endif  // SCUDO_UTILS_H_

compiler-rt/lib/scudo/scudo_utils.cpp

 
 extern int VSNPrintf(char *buff, int buff_length, const char *format,
                      va_list args);
 
 }  // namespace __sanitizer
 
 namespace __scudo {
 
-FORMAT(1, 2) void NORETURN dieWithMessage(const char *Format, ...) {
+void dieWithMessage(const char *Format, ...) {
   static const char ScudoError[] = "Scudo ERROR: ";
   static constexpr uptr PrefixSize = sizeof(ScudoError) - 1;
   // Our messages are tiny, 256 characters is more than enough.
   char Message[256];
   va_list Args;
   va_start(Args, Format);
   internal_memcpy(Message, ScudoError, PrefixSize);
   VSNPrintf(Message + PrefixSize, sizeof(Message) - PrefixSize, Format, Args);