[LLVMdev] Type::removeAbstractTypeUser crash when freeing module from ExecutionEngine

[Wesley Smith]

ok, let me try again.  When a type is added to
StructLayoutMap::LayoutInfo as a key, where is its refcount
incremented?  There seems to be an edge case where the Type is left in
the LayoutInfo map, but is freed due to a 0 refcount.  I have this
problem in both 2.8 and 2.9.

thanks
wes

On Sun, May 29, 2011 at 7:07 PM, Wesley Smith <wesley.hoke at gmail.com> wrote:
> hi list,
> I've got a situation where I'm constantly adding and removing Modules
> from an ExecutionEngine.  When removing a module and the jitstate is
> freed, clean up of the StructLayoutMap ends up trying to access a Type
> instance was was already freed by the removal of another Module.  In
> trying to debug this, it basically comes down to a Type instance
> serving as key in StructLayoutMap::LayoutInfo that shouldn't be there
> (or the Type key shouldn't have been freed although its refcount is
> 0).
>
> I've been scouring the code to find the point where types are added to
> StructLayoutMap::LayoutInfo but can't find it.  Looking in
> TargetData.cpp shows no code that actually adds entries to the map
> AFAICT and since StructLayoutMap is declared in the .cpp I don't see
> how it could be done anywhere else.  anyone know which line of code
> adds types/info pairs to StructLayoutMap::LayoutInfo?
>
> thanks in advance,
> wes
>