Re: [patch 3.4/3.5] libffi & libjava port for hppa-linux

[Andrew Haley <aph at redhat dot com>]

Andrew Haley writes:
 > fRandolph Chung writes:
 >  > > Yup.  Well, sorta: MD_FALLBACK_FRAME_STATE_FOR copies saved registers
 >  > > from the signal frame to _Unwind_FrameState and then sets things up so
 >  > > that the _next_ time uw_frame_state_for() is called, it returns the
 >  > > context of the point at which the signal was triggered.
 >  > 
 >  > sorry, i still don't understand.
 >  > 
 >  > in the case where you have 3 frames:
 >  > 
 >  > 3 [ sighandler ]
 >  > 2 [ sig frame  ]
 >  > 1 [ try-catch  ]
 >  > 
 >  > if the signal is triggered from the try-catch frame, and an exception is
 >  > thrown from the sighandler, how many times is uw_frame_state_for()
 >  > called? 
 > 
 > It's impossible to say.  Throwing an exception in turn generats more
 > frames.
 > 
 >  > i should mention that this case doesn't work on x86 either (with
 >  > g++-3.3). it works for libjava because there is always some more frames
 >  > between try-catch and the signal frame.

I meant to say: no, this is not the case.  There is not always some
more frames between try-catch and the signal frame.  If a signal is
delivered in a try {} block, for instance.

Andrew.