[clang] [sanitizer] Fix empty string in unsupported argument error for -fsanitize-trap (PR #136549)

[Thurston Dang via cfe-commits]

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@@ -259,6 +259,9 @@
 // RUN: not %clang --target=aarch64-linux -fsanitize=memtag -I +mte %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-SANMT-NOMT-1
 // CHECK-SANMT-NOMT-1: '-fsanitize=memtag-stack' requires hardware support (+memtag)
 
+// RUN: not %clang --target=aarch64-linux-android31 -fsanitize-trap=memtag -march=armv8-a+memtag -c %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-SANMT-TRAP
+// CHECK-SANMT-TRAP: error: unsupported argument 'memtag-stack,memtag-heap,memtag-globals' to option '-fsanitize-trap='
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thurstond wrote:

Optional: precommit this test to show that it currently prints
`unsupported argument '' to option '-fsanitize-trap='`

https://github.com/llvm/llvm-project/pull/136549