[compiler-rt] [libcxx] [libcxxabi] [libunwind] [libunwind][libcxx][libcxxabi][compiler-rt-builtins] Fix Exception Handling build for wasm (PR #79667)

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@@ -12,6 +12,7 @@
 #include <libunwind.h>
 
 #include "config.h"
+#ifndef __wasm__
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trcrsired wrote:

> I feel like we could detect `__wasm__` or similar in CMake. And it feels like the right tool, though maybe not the most trivial to implement.

Tbh i would always avoid wrapping around cmake, if platform macro works out.

https://github.com/llvm/llvm-project/pull/79667