[LLVMdev] LLVM segmentation fault / need use Instruction instead of Instruction*

[Óscar Fuentes]

Alexandru Ionut Diaconescu <alexandruionutdiaconescu at gmail.com> writes:

> I was following your procedures and I isolated the problem. The problem are
> represented by the basic blocks with only one element.
>
>
> for (Function::iterator II = F.begin(), EE = F.end(); II != EE; ++II, ++ii)
> {
> BasicBlock* BB=II;
>
>
> if (BB->getTerminator())
>     {
>         Instruction* current = BB->getTerminator();
>
>         Instruction* previous;
>
>         errs()<<"AAA\n";
>         if(*current->getPrevNode()*)
>         {
>             errs()<<"BBB\n";
>             previous = current->getPrevNode();
>             ok=1;
>         }
>
>         if (ok){
>            errs()<<"CCC\n";
>               ........
>
>
> It does print AAA, but then I have the segfault. So when I am evaluating
> the *current->getPrevNode() *condition, I got the segfault.
> Do you know how can I solve this?

The documentation for BasickBlock::getTerminator says:

  /// getTerminator() - If this is a well formed basic block, then this returns
  /// a pointer to the terminator instruction.  If it is not, then you get a
  /// null pointer back.

Maybe BB is not well formed (it doesn't have proper terminator) and
BB->getTerminator returns NULL ?