llvm dev - Sep 2011 - [LLVMdev] Segmentation fault while adding an addtional argument

Hi, all

I am trying to write a function pass to replace a old function to a new
function like:
int haha(int a) {  } ==> int haha(int a, char *IO) {   }

The below is a part of my code and generate segmentation fault. Can you help
me to fix it?
Thanks,
Shawn

    // Since we have now created the new function, splice the body of the
old
    // function right into the new function, leaving the old rotting hulk of
the
    // function empty.
    NF->getBasicBlockList().splice(NF->begin(), F.getBasicBlockList());

    Value *Globals = NF->arg_end();
    Globals->setName("globals");

=========================================================150       
Globals->setName("globals");
(gdb)

Program received signal SIGSEGV, Segmentation fault.
0x08591311 in llvm::StringRef::operator[] (this=0xbfffeca0, Index=0)
    at /home/skim/Etc/LLVM/llvm/include/llvm/ADT/StringRef.h:181
181          return Data[Index];
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On Tue, Sep 20, 2011 at 5:05 PM, Shawn Kim <shawn.subscribe at gmail.com>
wrote:
> Hi, all
>
> I am trying to write a function pass to replace a old function to a new
> function like:
> int haha(int a) {  } ==> int haha(int a, char *IO) {   }
>
> The below is a part of my code and generate segmentation fault. Can you
help
> me to fix it?
> Thanks,
> Shawn
>
>     // Since we have now created the new function, splice the body of the
> old
>     // function right into the new function, leaving the old rotting hulk
of
> the
>     // function empty.
>     NF->getBasicBlockList().splice(NF->begin(),
F.getBasicBlockList());
>
>     Value *Globals = NF->arg_end();
>     Globals->setName("globals");
You can't dereference arg_end... you might want to read up a bit on
C++ iterators.

-Eli