Hip wrapper

[scheibelp]

Used by spack/spack-packages#4411

Pipelines there fully passed with latest commit (d6cc6b2) 2b8ef4e (additional commit after that is for cleanup)

[scheibelp]

Question: should cxxflags attribute from compiler definitions (in packages.yaml) be added when detected language is HIP? or should there be a separate hipflags entry that adds flags to hip invocations. See https://github.com/spack/compiler-wrapper/blob/main/cc.sh#L789

Also, note that if it were processed like cxxflags: it would not work to add -x hip (because that gets placed after the source file, which is apparently important to amdclang++).

[haampie]

Did you check what CMake does? They implemented it twice, so presumably the second time they learned from mistakes from the past. See https://cmake.org/cmake/help/latest/variable/CMAKE_LANG_FLAGS.html#variable:CMAKE_%3CLANG%3E_FLAGS and various other pages, or sources.

Edit: I did that:

• CMake passes -x hip, it's not extension based; we should do the same, otherwise the compiler wrapper may at some point need compiler+version specific parsing in case the real compiler changes behavior.
• CMAKE_HIP_FLAGS_INIT is dervied from HIPFLAGS
• CXXFLAGS is unrelated to HIPFLAGS.

That makes sense cause it's a different language.

This is the case for ~5 years, so I would say let's do -x hip only and fix upstream packages if needed, or deprecate them if too difficult.