LLD warning after the LLVM15 switchover about archives not being ET_REL or LLVM bitcode

[mitchellh]

Zig Version

0.10.0-dev.4333+f5f28e0d2

Steps to Reproduce

I don't have a minimal test case, so this is more of a question at the moment. Ever since the LLVM15 merge, my C libraries building and then linking is emitting the following (one for each C library):

ld.lld: warning: /home/mitchellh/code/go/src/github.com/mitchellh/testproj/zig-cache/o/e90400f9bbd68db8d2168fd678ecf358/liblibpng.a: archive member '/home/mitchellh/code/go/src/github.com/mitchellh/testproj/zig-cache/o/c964bc1bea30b7769c1a8503666d8876/libz.a' is neither ET_REL nor LLVM bitcode

This warning doesn't seem to affect the actual behavior of the program at all, but I'm unsure how to fix it, and googling this exact error turns up only the LLD source code and the Mach project (another Zig project) 😄 So this appears to also be effecting the Mach project, which also builds and links a lot of C libraries!

I apologize using issues as a sort of question, but I'm unsure if this is a bug in the way Zig builds things or not.

This happens with both -fstage1 and without.

Expected Behavior

No warning.

Actual Behavior

Warning.

[matu3ba]

This looks related to #8531 or as a potential duplicate. Not sure, where tracking it is better.

[llogick]

lld/ELF/Driver.cpp ref

      auto magic = identify_magic(p.first.getBuffer());
      if (magic == file_magic::elf_relocatable)
        files.push_back(createObjFile(p.first, path, true));
      else if (magic == file_magic::bitcode)
        files.push_back(make<BitcodeFile>(p.first, path, p.second, true));
      else
        warn(path + ": archive member '" + p.first.getBufferIdentifier() +
             "' is neither ET_REL nor LLVM bitcode");

[mitchellh]

I don’t see this anymore, so I’m going to close this. I’m not sure what changed but given no one else has said anything I’ll just let it go.