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

[via cfe-commits]

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@@ -45,8 +45,11 @@ void lld::unlinkAsync(StringRef path) {
   if (!sys::fs::exists(path) || !sys::fs::is_regular_file(path))
     return;
 
+// If threads are disabled, remove the file synchronously.
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whitequark wrote:

I'm sorry, I don't quite understand. Are you asking me to change `ThreadPoolStrategy::ThreadsRequested` to be a constant? I could do that but it seems like an invasive change. Looking at other uses of `ThreadsRequested`, it looks like many of them are guarded in essentially the same way as what this patch introduces, e.g. here:

https://github.com/llvm/llvm-project/blob/6441df3b5930ff9f8b3b9af6fd5d2684cf9a337b/llvm/lib/Support/Parallel.cpp#L196-L201

or here:

https://github.com/llvm/llvm-project/blob/6441df3b5930ff9f8b3b9af6fd5d2684cf9a337b/llvm/lib/Support/Parallel.cpp#L227-L230



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