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

[Alexander Richardson via cfe-commits]

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@@ -12,7 +12,7 @@
 // functions. We need to ensure that the return value is sign-extended in the
 // same way as GCC expects (since otherwise GCC-generated __builtin_isinf
 // returns true for finite 128-bit floating-point numbers).
-#ifdef __aarch64__
+#if defined(__aarch64__) || defined(__wasm__)
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arichardson wrote:

Agreed, please leave an explicit comment here for WASM. When I ran into this issue it was really difficult to track down, so I really appreciate having explicit comments that show the rational for the special cases.

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