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

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@@ -39,3 +40,5 @@ extern void *__libunwind_cet_get_registers(unw_cursor_t *);
 extern void *__libunwind_cet_get_jump_target(void);
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EricWF wrote:

What is the problem with exposing these two declarations, even if they're not defined?

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