[clang] [analyzer] Fix security.VAList false positives with C23 va_start (PR #192024)

[Björn Svensson via cfe-commits]

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@@ -0,0 +1,16 @@
+// Like the compiler, the static analyzer treats some functions differently if
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bjosv wrote:

I don't see that we do. This header is also very similar to `system-header-simulator-for-valist.h`‎, except the difference what `va_start` is.


https://github.com/llvm/llvm-project/pull/192024