[clang] [lld] [llvm] Conditionalize use of POSIX features missing on WASI/WebAssembly (PR #92677)

[James Y Knight via cfe-commits]

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@@ -273,9 +273,19 @@ static bool printMarkupStackTrace(StringRef Argv0, void **StackTrace, int Depth,
 }
 
 // Include the platform-specific parts of this class.
-#ifdef LLVM_ON_UNIX
+#if defined(__wasi__)
+// WASI does not have signals.
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jyknight wrote:

Move these stubs to WASI/Signals.inc for consistency with the other platform support files.

https://github.com/llvm/llvm-project/pull/92677