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

[James Y Knight via cfe-commits]

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@@ -508,6 +512,9 @@ static bool is_local_impl(struct STATVFS &Vfs) {
 #elif defined(__EMSCRIPTEN__)
   // Emscripten doesn't currently support remote filesystem mounts.
   return true;
+#elif defined(__wasi__)
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jyknight wrote:

`__EMSCRIPTEN__ || __wasi__` is effectively equal `__wasm__`; merge clauses?

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