[clang] [lld] [llvm] [mlir] [LLVM][Windows] Elide `PrettyStackTrace` output for usage errors (PR #140956)

[Matt Arsenault via cfe-commits]

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@@ -1,15 +1,26 @@
-; REQUIRES: x86, non-root-user
-;; Not supported on windows since we use permissions to deny the creation
-; UNSUPPORTED: system-windows
+;; The output is OS-specific, so this test is limited to Windows.
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arsenm wrote:

Switching a test from "not windows" to "only windows" is suspicious. Is it just the error message phrasing? Can you follow the pattern of other tests that depend on error strings, e.g. llvm/test/tools/llvm-ar/error-opening-permission.test

https://github.com/llvm/llvm-project/pull/140956