> -----Original Message-----
> From: Richard Biener [mailto:[email protected]]
> Sent: Thursday, November 27, 2014 9:57 AM
> To: Ramana Radhakrishnan
> Cc: Thomas Preud'homme; 'Jonathan Wakely'; Jakub Jelinek; Tony Wang;
> [email protected]; [email protected]; aph-
> [email protected]; Richard Earnshaw; [email protected]
> Subject: Re: [Patch, ARM, ping1] Fix PR target/56846
>
> On Thu, 27 Nov 2014, Ramana Radhakrishnan wrote:
>
> >
> >
> > On 27/11/14 09:34, Richard Biener wrote:
> > > On Thu, 27 Nov 2014, Thomas Preud'homme wrote:
> > >
> > > > Thanks. Ccing release manager for their opinion.
> > >
> > > It doesn't look ARM specific and frankly I have not too much
> expertise
> > > in this area. The patch has been on trunk for more than two months
> > > though so I guess it is ok to backport.
> > >
> >
> > It is ARM specific because the whole thing sits in a #ifdef
> > __ARM_EABI_UNWINDER__ in eh_personality.cc.
>
> Ah, too little patch context then.
Sorry, my bad. Below is the patch that were sent by Tony at that time with 20
lines of context:
diff --git a/libstdc++-v3/libsupc++/eh_personality.cc
b/libstdc++-v3/libsupc++/eh_personality.cc
index f315a83..cb4467a 100644
--- a/libstdc++-v3/libsupc++/eh_personality.cc
+++ b/libstdc++-v3/libsupc++/eh_personality.cc
@@ -361,40 +361,46 @@ PERSONALITY_FUNCTION (int version,
found_cleanup,
found_handler
} found_type;
lsda_header_info info;
const unsigned char *language_specific_data;
const unsigned char *action_record;
const unsigned char *p;
_Unwind_Ptr landing_pad, ip;
int handler_switch_value;
void* thrown_ptr = 0;
bool foreign_exception;
int ip_before_insn = 0;
#ifdef __ARM_EABI_UNWINDER__
_Unwind_Action actions;
switch (state & _US_ACTION_MASK)
{
case _US_VIRTUAL_UNWIND_FRAME:
+ // If the unwind state pattern is
+ // _US_VIRTUAL_UNWIND_FRAME | _US_FORCE_UNWIND
+ // then we don't need to search for any handler as it is not a real
+ // exception. Just unwind the stack.
+ if (state & _US_FORCE_UNWIND)
+ CONTINUE_UNWINDING;
actions = _UA_SEARCH_PHASE;
break;
case _US_UNWIND_FRAME_STARTING:
actions = _UA_CLEANUP_PHASE;
if (!(state & _US_FORCE_UNWIND)
&& ue_header->barrier_cache.sp == _Unwind_GetGR(context,
UNWIND_STACK_REG))
actions |= _UA_HANDLER_FRAME;
break;
case _US_UNWIND_FRAME_RESUME:
CONTINUE_UNWINDING;
break;
default:
std::abort();
}
actions |= state & _US_FORCE_UNWIND;
Best regards,
Thomas
