[LLVMdev] Strange Multiple Inheritance Errors Using LLVM 2.7

[John Criswell]

Dear All,

I'm currently upgrading SAFECode to the LLVM 2.7 API.  I'm getting some 
strange errors in LLVM Passes that use analysis groups and multiple 
inheritance.

To create analysis groups in LLVM 2.6, I would first create a base class 
for the analysis group and then another class that inherited from both 
ModulePass and the analysis group base class.  That worked in LLVM 2.6, 
but now in LLVM 2.7 I'm getting strange behavior.  In particular, I'm 
seeing the wrong functions called when virtual methods of my passes are 
called.  For example, when a SAFECode pass would call the getDSGraph() 
method of the PoolAllocateSimple pass, the releaseMemory() method would 
be called instead.

Has anyone else seen this really bizarre behavior or know what might be 
causing it?  Eliminating multiple inheritance seems to fix the problem, 
but it seems to introduce other problems when chaining analysis passes 
of the same group together.

I see this behavior both on Mac OS X and Linux.

-- John T.