[clang] [OpenCL][NFC] test get_image_height with -finclude-default-header (PR #176683)

[Sven van Haastregt via cfe-commits]

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@@ -0,0 +1,118 @@
+// RUN: %clang_cc1 %s -triple spir64 -cl-std=CL2.0 -finclude-default-header -verify -pedantic -fsyntax-only
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svenvh wrote:

Parsing the full `opencl-c.h` header takes time, so I think these two RUN lines will add significantly to the runtime of `check-clang`.

I wonder why the old `opencl-c.h` header is still important to your use case, and whether switching to `-fdeclare-opencl-builtins` is an option?  `-fdeclare-opencl-builtins` should be much faster.

https://github.com/llvm/llvm-project/pull/176683