[clang-tools-extra] [clang-tidy] Add `modernize-use-bit-cast` check (PR #189962)

[Yanzuo Liu via cfe-commits]

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@@ -0,0 +1,22 @@
+// RUN: %check_clang_tidy -std=c++20-or-later %s modernize-use-bit-cast %t
+
+void *memcpy(void *To, const void *From, int Size);
+
+namespace std {
+void *memcpy(void *To, const void *From, __SIZE_TYPE__ Size);
+}
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zwuis wrote:

Move it to `clang-tools-extra/test/clang-tidy/checkers/Inputs/Headers/std/cstddef` and `clang-tools-extra/test/clang-tidy/checkers/Inputs/Headers/std/stddef.h`, then `#include <cstddef>`.

https://github.com/llvm/llvm-project/pull/189962