[LLVMdev] RFC: Patch for CFA on Darwin

[Bill Wendling]

Hi Anton,

> > The reason for it: when going to calculate the CFA in LLVM, the
> > original code was adding an offset of type i32 to a pointer. This is
> > fine if pointers are 32-bits, but we get an assert if the types are
> > different. By converting the cfa_offset to a pointer, we get it to be
> > that size.
> Please ignore my prev. e-mail. The code breaks at least 32-bit stuff.
> The arg of eh_dwarf_cfa is i32, how it can be pointer?
>
The built-in dwarf_cfa doesn't take an argument. It returns a pointer.
But there's an offset associated with the CFA. So it looks like LLVM
is taking the pointer and adding the offset to it to synthesize what
GCC is doing. I was running it on a 64-bit machine (I didn't know that
EH was broken on it), so that's why I had these problems. I thought
that there could be 32-bit pointers on a 32-bit system, but maybe I'm
wrong? :-)

-bw