Pass through file-compilation-dir to the ClangImporter.

[rmaz]

This change passes through the -file-compilation-dir flag to the ClangImporter instance as -ffile-compilation-dir. When used in conjunction with llvm/llvm-project#67744 this will allow for setting the compilation directory of pcm files using the -file-compilation-dir flag.

[adrian-prantl]

This looks reasonable, but can you add a test case?

[rmaz]

This looks reasonable, but can you add a test case?

I had trouble thinking what we could test. Until llvm/llvm-project#67744 is merged into the swift llvm branch there will be no observable behaviour change. Should I put up a PR for that first on apple/llvm-project?

[adrian-prantl]

I think that would be best — you'll want to cherry-pick it to stable/20230725 which aligns with rebranch, which will become the new main soon.

[rmaz]

Cherry-pick over here: swiftlang/llvm-project#7546

which aligns with rebranch, which will become the new main soon.

So I should sit on this until the rebranch is done then update with a test?

[adrian-prantl]

Yeah, or land this on the rebranch branch before then.

[rmaz]

@swift-ci Please test

[rmaz]

@swift-ci Please test Windows platform

[drodriguez]

@shahmishal, @compnerd : the comment 4 hours ago left "Swift Test Windows Platform" in "Expected - Waiting for status to be reported". I don't know if you are still tracking those or not.

[shahmishal]

@swift-ci Please test Windows platform