$ gdb  ./tests/.libs/Gtest-resume-sig
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Reading symbols from ./tests/.libs/Gtest-resume-sig...done.
(gdb) b handler
Breakpoint 1 at 0x401032: file Gtest-resume-sig.c, line 75.
(gdb) r
Starting program: /public/hplibunwind/tests/.libs/Gtest-resume-sig 
[New LWP 1 of process 788]
sending SIGUSR1 IP=4014ec

Thread 2 received signal SIGUSR1, User defined signal 1.
0x00007f7ff703bf9a in kill () from /usr/lib/libc.so.12
(gdb) signal SIGUSR1
Continuing with signal SIGUSR1.

Thread 2 hit Breakpoint 1, handler (sig=30) at Gtest-resume-sig.c:75
75      {
(gdb) bt
#0  handler (sig=30) at Gtest-resume-sig.c:75
#1  0x00007f7ff70a3530 in _opendir (name=<optimized out>) at /usr/src/lib/libc/gen/opendir.c:72
#2  0x000000000000001e in ?? ()
#3  0x0000000000000000 in ?? ()
(gdb) disassemble 0x00007f7ff70a3530
Dump of assembler code for function __sigtramp_siginfo_2:
   0x00007f7ff70a3530 <+0>:     mov    %r15,%rdi
   0x00007f7ff70a3533 <+3>:     mov    $0x134,%rax
   0x00007f7ff70a353a <+10>:    syscall 
   0x00007f7ff70a353c <+12>:    mov    $0xffffffffffffffff,%rdi
   0x00007f7ff70a3543 <+19>:    mov    $0x1,%rax
   0x00007f7ff70a354a <+26>:    syscall 
End of assembler dump. 
(gdb) info frame 
Stack level 0, frame at 0x7f7fffffe2a0:
 rip = 0x401032 in handler (Gtest-resume-sig.c:75); saved rip = 0x7f7ff70a3530
 called by frame at 0x7f7fffffe2a8
 source language c.
 Arglist at 0x7f7fffffe290, args: sig=30
 Locals at 0x7f7fffffe290, Previous frame's sp is 0x7f7fffffe2a0
 Saved registers:
  rip at 0x7f7fffffe298
(gdb) f 1
#1  0x00007f7ff70a3530 in _opendir (name=<optimized out>) at /usr/src/lib/libc/gen/opendir.c:72
72              return (__opendir2(name, DTF_HIDEW|DTF_NODUP));
(gdb) info frame
Stack level 1, frame at 0x7f7fffffe2a8:
 rip = 0x7f7ff70a3530 in _opendir (/usr/src/lib/libc/gen/opendir.c:72); saved rip = 0x1e
 called by frame at 0x7f7fffffe2b0, caller of frame at 0x7f7fffffe2a0
 source language c.
 Arglist at 0x7f7fffffe298, args: name=<optimized out>
 Locals at 0x7f7fffffe298, Previous frame's sp is 0x7f7fffffe2a8
 Saved registers:
  rbx at 0x7f7fffffe298, rip at 0x7f7fffffe2a0
(gdb)