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

[via cfe-commits]

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@@ -15,6 +15,7 @@
 
 #include <__libunwind_config.h>
 
+#ifndef __wasm__
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trcrsired wrote:

it does not compile. all the definitions are not defined

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