[LLVMdev] Crash in opt.cpp:739 when loading custom pass (only on system-wide debug install of llvm)

[Maciej Piechotka]

On Wed, 2013-12-25 at 05:33 +0100, Maciej Piechotka wrote:
> Hi,
> 
> I'm trying to write custom pass. However opt started crashed in opt.cpp.
> After debugging it looks like PassInf->NormalCtor points to unmapped
> memory (rest of struct contains correct data about my pass) - it pointed
> high in user memory (0x756e672e006e6f69).
> 
> It happens only when I tried to install debug version of llvm
> system-wide (I've check that it wasn't caused by stale .a files). When I
> used the local install (via cmake to $HOME) or release it works[1].
> 
> My system is Gentoo, 64 bit. To bootstrap I've used gcc 4.8.2.
> 
> Any idea what might be a cause of it (my build system is practically
> copied from documentation[2])?
> 
> Best regards
> 
> PS. The difference seems to be in system-wide install only
> optimized/assertions/expensive-checks flags (I'm using Gentoo ebuild).
> 
> [1] The problem with local install is that it cause problems with clang
> (probably because of some incompatibilities between released version
> clang was compiled against and debug version it's loading) and release
> version don't have debug flags support etc.
> [2] http://llvm.org/docs/CMake.html#developing-llvm-pass-out-of-source

When I tried to manually rewrite the RegisterPass:

struct RegisterMyPass {
  RegisterMyPass();
};

llvm::Pass *create_my_pass() {
  return new vallvm::MyPass();
}

RegisterMyPass::RegisterMyPass() {
  static llvm::PassInfo info(...,
    ...,
    &vallvm::MyPass::ID,
    create_my_pass,
    false, false);
  if (info.getNormalCtor() == create_closure_capture) {
    llvm::errs() << "???\n";
    info.setNormalCtor(create_closure_capture);
    if (info.getNormalCtor() == create_closure_capture) {
      llvm::errs() << "???\n";
    }
  }
  llvm::PassRegistry::getPassRegistry()->registerPass(info);
}

With debug built it prints "???" twice. 

Regards
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