[clang] [Clang] Added clang diagnostic when snprintf/vsnprintf uses sizeof(de… (PR #170637)

[Oliver Hunt via cfe-commits]

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@@ -188,3 +188,12 @@ void strcpy_and_friends() {
   strndup(FOO, sizeof(FOO)); // \
       // expected-warning {{'strndup' call operates on objects of type 'const char' while the size is based on a different type 'const char *'}} expected-note{{did you mean to provide an explicit length?}}
 }
+
+extern "C" int snprintf(char* buffer, __SIZE_TYPE__ buf_size, const char* format, ...);
+extern "C" void* malloc(unsigned size);
+
+void check_prints(){
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ojhunt wrote:

Hooray! Paranoid testing for the win! :D

https://github.com/llvm/llvm-project/pull/170637