[Flang] [Driver] ResourceDir changes cause lit failures on AIX

[madanial0]

ResourceDir changes from #90886, change the ResourceDir from: ~/build/lib/clang/19 to ~/build/bin/.. which cause linking issues on AIX as ppc builtins are not found in ~/build/bin/../lib/aix/libclang_rt.builtins-powerpc64.a which were previously accessible in ~/build/lib/clang/19/lib/aix/libclang_rt.builtins-powerpc64.a. This causes issues with the following 2 lit test cases:

  Flang :: Driver/ctofortran.f90
  Flang :: Driver/exec.f90

Does this happen for any other platforms besides AIX? Is there a functional reason behind the change for ResourceDir in flang? I saw @mjklemm comments about "have it point to where the MODULE files live." but it seems there was some functionality associated with the ResourceDir. It might seem that we may need another ResourceDir for flang.

[llvmbot]

@llvm/issue-subscribers-flang-driver

Author: None (madanial0)

ResourceDir changes from https://github.com//pull/90886, change the ResourceDir from: `~/build/lib/clang/19` to `~/build/bin/..` which cause linking issues on AIX as ppc builtins are not found in `~/build/bin/../lib/aix/libclang_rt.builtins-powerpc64.a` which were previously accessible in `~/build/lib/clang/19/lib/aix/libclang_rt.builtins-powerpc64.a`. This causes issues with the following 2 lit test cases: ``` Flang :: Driver/ctofortran.f90 Flang :: Driver/exec.f90 ``` Does this happen for any other platforms besides AIX? Is there a functional reason behind the change for ResourceDir in flang? I saw @mjklemm comments about "have it point to where the MODULE files live." but it seems there was some functionality associated with the ResourceDir. It might seem that we may need another `ResourceDir` for flang.

[mjklemm]

It seems kind of wrong that Flang tries to find its resources in a subfolder of Clang. Maybe the failing parts should be moved to the new location instead.

I'd like to also note, that Flang did not have the notion of a resource dir at all and so, it falsely abused Clang's resource dir (more by accident that by design). So, I mildly argue for creating a similar resource dir structure also for Flang.

[kkwli]

libclang_rt.builtins.*.a is built in compiler-rt. Since flang shares the driver with clang, it inherits the path from there as far as I understand. I agree that it is kind of strange to pick up something from the clang directory. Since libclang_rt.builtins.*.a is shared between, perhaps we need to put the library in a different directory. Just a thought.