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

[Louis Dionne via cfe-commits]

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@@ -10,14 +10,11 @@
 //
 //===----------------------------------------------------------------------===//
 
+#if __STDC_VERSION__ < 202311L
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ldionne wrote:

This change seems unrelated to the rest of the patch.

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