[libunwind] [libunwind] Enable wasm target for exceptions (PR #168449)

[Heejin Ahn via cfe-commits]

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@@ -254,6 +254,8 @@ aliasname:                                                                     \
 #define NO_EXEC_STACK_DIRECTIVE
 
 // clang-format on
+#elif defined(__wasm__)
+
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aheejin wrote:

In which case wasm needs to include this file?

https://github.com/llvm/llvm-project/pull/168449