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

[James Y Knight via cfe-commits]

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@@ -13,8 +13,17 @@
 #include "llvm/Support/Signals.h"
 #include "llvm/Support/thread.h"
 #include <cassert>
+#if !defined(__wasi__)
+#include <csignal>
+#endif
+#if LLVM_ENABLE_THREADS
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jyknight wrote:

This is unfortunate; there's no reason (in theory) that mutex shouldn't work fine in single-threaded mode.

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