The test were using the DXC driver in Clang, which adds the `--spirv-ext=` option. Turns out some buildbots are built without this flag support, meaning any test using this driver would fail with an 'unknown command line argument' error.
The test were using the DXC driver in Clang, which adds the `--spirv-ext=` option. Turns out some buildbots are built without this flag support, meaning any test using this driver would fail with an 'unknown command line argument' error.