[clang] Check for unsupported target options even with -Qunused-arguments (PR #141698)

[Fangrui Song via cfe-commits]

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@@ -27,3 +27,10 @@
 // RUN: not %clang --target=x86_64 -### -mhtm -lc %s 2>&1 \
 // RUN:   | FileCheck %s -check-prefix=UNSUP_OPT
 // UNSUP_OPT: error: unsupported option
+
+
+// RUN: not %clang -c --target=aarch64-- -mfpu=crypto-neon-fp-armv8 %s 2>&1 | \
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MaskRay wrote:

This RUN line without -Qunused-arguments doesn't add test coverage. It can be removed

https://github.com/llvm/llvm-project/pull/141698