[compiler-rt] [asan] Avoid -Wpointer-bool-conversion warning by explicitly casting (PR #164906)

[Thurston Dang via llvm-commits]

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@@ -58,15 +58,15 @@ namespace __asan {
 
 static inline uptr MaybeRealStrnlen(const char *s, uptr maxlen) {
 #if SANITIZER_INTERCEPT_STRNLEN
-  if (REAL(strnlen))
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thurstond wrote:

I'm worried there might be edge cases where REAL(strnlen) is defined to be zero but not a pointer.

https://github.com/llvm/llvm-project/pull/164906