[clang] [clang] Rewrite tests relying on shell environment variable features (PR #156904)

[Aiden Grossman via cfe-commits]

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@@ -10,7 +8,9 @@
 // RUN: echo "@subdir/cfg-s2" > %t/workdir/cfg-1
 // RUN: echo "-Wundefined-var-template" > %t/workdir/subdir/cfg-s2
 //
-// RUN: ( cd %t && %clang --config=workdir/cfg-1 -c -### %s 2>&1 | FileCheck %s -check-prefix CHECK-REL )
+// RUN: pushd %t
+// RUN: %clang --config=workdir/cfg-1 -c -### %s 2>&1 | FileCheck %s -check-prefix CHECK-REL
+// RUN: popd
 //
 // CHECK-REL: Configuration file: {{.*}}/workdir/cfg-1
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boomanaiden154 wrote:

It's failing due to the FileCheck lines using forward slashes, but Windows using backward slashes by default. (which is what you pointed out here but not something I realized until later). This test also requires symlinks. I'm just going to mark it unsupported since we aren't using any test coverage.

https://github.com/llvm/llvm-project/pull/156904