[Bug target/28854] unwinder reports sentinel frame.

[ubizjak at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28854

--- Comment #5 from Uros Bizjak  2011-10-24 14:44:49 
UTC ---
Just FYI, this is due to the fact that _start from /usr/crt1.o has a FDE:

$ objdump --dwarf  /usr/lib/crt1.o 

/usr/lib/crt1.o: file format elf64-alpha

Contents of the .eh_frame section:

 0010  CIE
  Version:   1
  Augmentation:  "zR"
  Code alignment factor: 4
  Data alignment factor: -8
  Return address column: 15
  Augmentation data: 1b

  DW_CFA_def_cfa_register: r30
  DW_CFA_nop

0014 0010 0018 FDE cie= pc=..003c
  DW_CFA_advance_loc: 20 to 0014
  DW_CFA_def_cfa_register: r15

This FDE of _start function is discovered by uw_frame_state_for, and only after
this recursion

  if (context->ra == 0)
return _URC_END_OF_STACK;

is triggered.

So if there is a bug at all, it is in glibc - perhaps_start should not set FDE.

[Bug target/28854] unwinder reports sentinel frame.

[ubizjak at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28854

Uros Bizjak  changed:

   What|Removed |Added

 Status|UNCONFIRMED |RESOLVED
 Resolution||WONTFIX

--- Comment #4 from Uros Bizjak  2011-06-22 22:15:25 
UTC ---
(In reply to comment #3)
> please close this issue, my last alpha hardware died.

Wontfix.

[Bug target/28854] unwinder reports sentinel frame.

[pluto at agmk dot net]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28854

Pawel Sikora  changed:

   What|Removed |Added

  Known to fail||

--- Comment #3 from Pawel Sikora  2011-06-22 21:48:28 
UTC ---
please close this issue, my last alpha hardware died.

[Bug target/28854] unwinder reports sentinel frame.

[pluto at agmk dot net]

--- Comment #2 from pluto at agmk dot net  2006-11-07 14:14 ---
ping, please update status.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28854

[Bug target/28854] unwinder reports sentinel frame.

[pluto at agmk dot net]

--- Comment #1 from pluto at agmk dot net  2006-08-25 23:28 ---
the 0x12668 is a last valid return point.

0x00012630 <_start+0>:  br  gp,0x12634 <_start+4>
0x00012634 <_start+4>:  ldahgp,2(gp)
0x00012638 <_start+8>:  lda gp,-31092(gp)
0x0001263c <_start+12>: subqsp,0x10,sp
0x00012640 <_start+16>: mov 0,fp
0x00012644 <_start+20>: ldq a0,-32728(gp)
0x00012648 <_start+24>: ldl a1,16(sp)
0x0001264c <_start+28>: lda a2,24(sp)
0x00012650 <_start+32>: ldq a3,-32736(gp)
0x00012654 <_start+36>: ldq a4,-32752(gp)
0x00012658 <_start+40>: mov v0,a5
0x0001265c <_start+44>: stq sp,0(sp)
0x00012660 <_start+48>: ldq t12,-32720(gp)
0x00012664 <_start+52>: jsr ra,(t12),0x12668 <_start+56>
0x00012668 <_start+56>: halt
0x0001266c <_start+60>: unop


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28854