[clang] [libunwind] [libunwind][WebAssembly] Make libunwind compilable (PR #92192)

[Anton Korobeynikov via cfe-commits]

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@@ -20,7 +20,7 @@
   .text
 #endif
 
-#if !defined(__USING_SJLJ_EXCEPTIONS__)
+#if !defined(__USING_SJLJ_EXCEPTIONS__) && !defined(__wasm__)
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asl wrote:

Ok. Then does the clang change really belong here? `LIBUNWIND_USES_WASM_EXCEPTIONS` also seems to be unused.

https://github.com/llvm/llvm-project/pull/92192