LLVM 15 library is broken

[lerno]

brew gist-logs <formula> link OR brew config AND brew doctor output

Spaceman:temp lerno$ brew gist-logs llvm
Error: No logs.

Verification

• I ran brew update and am still able to reproduce my issue.
• I have resolved all warnings from brew doctor and that did not fix my problem.

What were you trying to do (and why)?

Linking to LLVM 15 to compile a compiler.

What happened (include all command output)?

Linking fails due the compiler being a different version than the one LLVM is compiled with:

ld: in /usr/local/opt/llvm/lib/libLLVMTarget.a(Target.cpp.o), could not parse object file
 /usr/local/opt/llvm/lib/libLLVMTarget.a(Target.cpp.o): 'Not an int attribute
 (Producer: 'LLVM15.0.1' Reader: 'LLVM APPLE_1_1316.0.21.2.5_0')', using libLTO 
 version 'LLVM version 13.1.6, (clang-1316.0.21.2.5)' for architecture x86_64

What did you expect to happen?

Compile the program. Just like it does for all previous brew versions, like llvm@14, llvm@13 etc.

Step-by-step reproduction instructions (by running brew commands)

brew install llvm

Then link with libLLVMTarget.a using Clang 13.

The problem is that LLVM@15 is compiled with the thinLTO option. That makes the library compiler version dependent. And worse, dependent on a later compiler version than is normally installed on MacOS is XCode is used.

The solution is simple: remove the thinLTO directive.

[carlocab]

Will be fixed in #112154.

[carlocab]

Should be fixed now. Do

brew update && brew reinstall llvm

[lerno]

Works, thank you!