[clang] [llvm] [Sema] Implement support for -Wformat-signedness (PR #74440)

[via llvm-commits]

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@@ -0,0 +1,107 @@
+// RUN: %clang_cc1 -std=c11 -fsyntax-only -verify -Wformat -Wformat-signedness %s
+
+int printf(const char *restrict format, ...);
+int scanf(const char * restrict, ...);
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apple-fcloutier wrote:

Please add tests with enum values:

```c
#include <limits.h>

enum foo {
	minus_one = -1,
	int_val = INT_MAX,
	unsigned_val = (unsigned)INT_MIN
};
```

https://github.com/llvm/llvm-project/pull/74440