[clang] [clang][sema] Add nonnull attribute to builtin format functions (PR #158626)

[via cfe-commits]

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@@ -0,0 +1,74 @@
+// RUN: %clang_cc1 -fsyntax-only -verify -Wnonnull -Wno-format-security %s
+
+#include <stdarg.h>
+#include <stddef.h>
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Sirraide wrote:

```suggestion
typedef __SIZE_TYPE__ size_t;
```
Clang tests should generally never include stdlib headers. If you need definitions from those headers, define them yourself (for `size_t` in particular, you can do `typedef __SIZE_TYPE__ size_t`).

https://github.com/llvm/llvm-project/pull/158626