Re: [Qemu-devel] gcc auto-omit-frame-pointer vs msvc longjmp

[asmwarrior]

On 2011-10-20 23:34, Kai Tietz wrote:
> Hi,
> 
> For trunk-version I have a tentative patch for this issue.  On 4.6.x
> and older branches this doesn't work, as here we can't differenciate
> that easy between ms- and sysv-abi.
> 
> But could somebody give this patch a try?
> 
> Regards,
> Kai
> 
> ChangeLog
> 
>          * config/i386/i386.c (ix86_frame_pointer_required): Enforce use of
>          frame-pointer for 32-bit ms-abi, if setjmp is used.
> 
> Index: i386.c
> ===================================================================
> --- i386.c      (revision 180099)
> +++ i386.c      (working copy)
> @@ -8391,6 +8391,10 @@
>     if (SUBTARGET_FRAME_POINTER_REQUIRED)
>       return true;
> 
> +  /* For older 32-bit runtimes setjmp requires valid frame-pointer.  */
> +  if (TARGET_32BIT_MS_ABI&&  cfun->calls_setjmp)
> +    return true;
> +
>     /* In ix86_option_override_internal, TARGET_OMIT_LEAF_FRAME_POINTER
>        turns off the frame pointer by default.  Turn it back on now if
>        we've not got a leaf function.  */
> 

I just see two related links about this issue:

see:
http://stackoverflow.com/questions/5887552/setjmp-and-omit-frame-pointer

and

http://connect.microsoft.com/VisualStudio/feedback/details/666704/visual-c-generates-incorrect-code-with-omit-frame-pointer-and-setjmp

I'm not sure microsoft has fix this issue.

asmwarrior
ollydbg from codeblocks' forum