[clang] [clang][test][OpenMP] Fix test assumptions of libomp and clang paths (PR #125891)

[Jordan Rupprecht via cfe-commits]

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@@ -1,49 +1,49 @@
 // REQUIRES: x86-registered-target, amdgpu-registered-target
 
 // Fail on invalid ROCm Path.
-// RUN:   not %clang -### --target=x86_64-unknown-linux-gnu -fopenmp --offload-arch=gfx908:xnack+ -fsanitize=address -fgpu-sanitize -nogpuinc --rocm-path=%S/Inputs/rocm-invalid  %s 2>&1 \
+// RUN:   not %clang -no-canonical-prefixes -### --target=x86_64-unknown-linux-gnu -fopenmp=libomp --offload-arch=gfx908:xnack+ -fsanitize=address -fgpu-sanitize -nogpuinc --rocm-path=%S/Inputs/rocm-invalid  %s 2>&1 \
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rupprecht wrote:

Yes, that's right.

BTW, it's actually quite common that tests uses explicit `fopenmp=` values:
* https://github.com/llvm/llvm-project/blob/d9a7498aa24a35bdd95fd20a5c63e9495b6669f6/clang/test/Driver/openmp-offload-gpu.c#L8
* https://github.com/llvm/llvm-project/blob/d9a7498aa24a35bdd95fd20a5c63e9495b6669f6/clang/test/Driver/aix-ld.c#L1024
* https://github.com/llvm/llvm-project/blob/d9a7498aa24a35bdd95fd20a5c63e9495b6669f6/clang/test/Driver/openmp-offload-jit.c#L3
* etc

See also https://github.com/llvm/llvm-project/commit/a5098e5f27badc3ba16533418accd2e17641e4e4

https://github.com/llvm/llvm-project/pull/125891