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

[via cfe-commits]

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@@ -12,6 +12,7 @@
 #ifndef __LIBUNWIND_EXT__
 #define __LIBUNWIND_EXT__
 
+#ifndef __wasm__
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trcrsired wrote:

wasm has its own exception handling mechanism. i do not know why __USING_WASM_EXCEPTION__ is not defined, because the author of the code did not change the upstream code correctly i guess.

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