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I'm developing some C/C++/Objective C static analysis utility which works with llvm bytecode files. Its basic idea is quite simple:
1. Utility executes clang/clang++ with arguments "-c -emit-llvm -femit-all-decls -g" to generate llvm bytecode file for tested source file.
2. If file was created it's being read by LLVM C bindings and checked. Problems related to some specific code points are reported with source references since there are debug metadata with source references.

I've had a prototype of my utility which worked fine, but recently I've updated Xcode to 6.1 and source references became missing.
To fix this I've tried to rebuild my tool and llvm static libraries with updated compiler, but it didn't solved my problem. I've tried to receive any hints from llvm, and the only thing I finally got is:

➜ bin ./llvm-dis test.bc
warning: ignoring debug info with an invalid version (600054001) in test.bc

So llvm-dis has shown me above warning and produced test.ll file which was stripped of any debug metadata attributes.

This is my simple test source file which I'm playing with:

int returnFive() {
    return 5;
}

and some info which may be helpful:

➜ bin clang --version
Apple LLVM version 6.0 (clang-600.0.54) (based on LLVM 3.5svn)
Target: x86_64-apple-darwin14.0.0
Thread model: posix
➜ bin ./llvm-config --version
3.5.0
➜ bin ./llvm-config --host-target
x86_64-apple-darwin14.0.0

For me this seems very compatible, but it isn't so maybe someone can give me any suggestions on how to resolve this?

okutane
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1 Answers1

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While I'm still not comfortable with the solution, I've hacked LLVM code and removed the call to llvm::UpgradeDebugInfo method from BitcodeReader::MaterializeModule code. Of course I may be punished for this if some truly incompatible LLVM compiler is used, but for now it works, furthermore not only clang from XCode can be used, but as well I can use Clang from LLVM release page which also produces "debug info with invalid version (0)".

okutane
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