Re: [RFC] pb unwinding from pthread_cond_wait on ppc-linux (RFA?)

[Joel Brobecker <brobecker at adacore dot com>]

> > I think that the reason that gdb-6.0 worked is a bit related to luck.
> > Here are the first few instructions of pthread_cond_timedwait():
> > 
> >     0x0ffe45b4 <pthread_cond_timedwait+0>:     stwu    r1,-128(r1)
> >     0x0ffe45b8 <pthread_cond_timedwait+4>:     mflr    r8
> >     0x0ffe45bc <pthread_cond_timedwait+8>:     lis     r7,15258
> >     0x0ffe45c0 <pthread_cond_timedwait+12>:    bl      0xffed01c
> >     0x0ffe45c4 <pthread_cond_timedwait+16>:    stw     r8,132(r1)
> 
> What's the bl actually calling?

(strange that the information appears to have gotten lost somewhere
during the copy/paste). According to GDB:

        bl      0xffed01c <stack_used+8>

But then, when I try to look deeper:

        (gdb) disass &stack_used
        Dump of assembler code for function stack_used:
        0x0ffed014 <stack_used+0>:      addic   r2,r2,-5280
        0x0ffed018 <stack_used+4>:      addic   r2,r2,-5280
        End of assembler dump.

ie, stack_used+8 does not exist... However:

        (gdb) x /10i 0xffed01c
        0xffed01c <stack_used+8>:       blrl
        0xffed020 <stack_used+12>:      .long 0x10f10
        0xffed024 <stack_used+16>:      .long 0x0
        0xffed028 <stack_used+20>:      .long 0x0
        0xffed02c <stack_used+24>:      twi     31,r30,-12756
        0xffed030 <stack_used+28>:      twi     31,r30,1928
        0xffed034 <stack_used+32>:      twi     31,r30,-24472
        0xffed038 <stack_used+36>:      twi     31,r30,-12280
        0xffed03c <stack_used+40>:      twi     31,r30,-11904
        0xffed040 <stack_used+44>:      twi     31,r30,-12276

Gah? Do I understand correctly that the code jumps to 0xffed01c
only to return back?

-- 
Joel