% gdb /scratch/tmp/ashish/objs/scratch/tmp/ashish/ghc/work/ghc-7.0.3-boot/lib/ghc-7.0.3/ghc
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This GDB was configured as "amd64-marcel-freebsd"...
(gdb) core-file  /scratch/tmp/ashish/distfiles/ghc-7.0.3/testsuite/tests/ghc-regress/ghc.core
Core was generated by `ghc'.
Program terminated with signal 11, Segmentation fault.
Reading symbols from /lib/libthr.so.3...done.
Loaded symbols for /lib/libthr.so.3
Reading symbols from /lib/libncursesw.so.8...done.
Loaded symbols for /lib/libncursesw.so.8
Reading symbols from /usr/lib/librt.so.1...done.
Loaded symbols for /usr/lib/librt.so.1
Reading symbols from /lib/libutil.so.9...done.
Loaded symbols for /lib/libutil.so.9
Reading symbols from /usr/local/lib/libiconv.so.3...done.
Loaded symbols for /usr/local/lib/libiconv.so.3
Reading symbols from /usr/local/lib/libgmp.so.10...done.
Loaded symbols for /usr/local/lib/libgmp.so.10
Reading symbols from /lib/libm.so.5...done.
Loaded symbols for /lib/libm.so.5
Reading symbols from /lib/libc.so.7...done.
Loaded symbols for /lib/libc.so.7
Reading symbols from /libexec/ld-elf.so.1...done.
Loaded symbols for /libexec/ld-elf.so.1
#0  0x0000000801efb6bd in _rtld_atfork_pre () from /libexec/ld-elf.so.1
[New Thread 803807c00 (LWP 107597/ghc)]
[New Thread 803807800 (LWP 107085/ghc)]
[New Thread 803807400 (LWP 100063/ghc)]
(gdb) bt
#0  0x0000000801efb6bd in _rtld_atfork_pre () from /libexec/ld-elf.so.1
#1  0x0000000801efed79 in _rtld_atfork_pre () from /libexec/ld-elf.so.1
#2  0x0000000801ef156d in _rtld_error () from /libexec/ld-elf.so.1
#3  0x0000000801ef4c53 in dlopen () from /libexec/ld-elf.so.1
#4  0x00000008021470a7 in pthread_attr_get_np () from /lib/libthr.so.3
#5  0x00000008021471db in pthread_exit () from /lib/libthr.so.3
#6  0x000000080213c22c in pthread_getprio () from /lib/libthr.so.3
#7  0x0000000000000000 in ?? ()
Cannot access memory at address 0x7fffffbfe000
(gdb) disassemble 0x00000008021470a7
Dump of assembler code for function pthread_attr_get_np:
.........
.........
---Type <return> to continue, or q <return> to quit---
0x0000000802147074 <pthread_attr_get_np+1300>:  callq  0x802146da0 <pthread_attr_get_np+576>
0x0000000802147079 <pthread_attr_get_np+1305>:  movl   $0x0,0xf8(%rbp)
0x0000000802147083 <pthread_attr_get_np+1315>:  xor    %edx,%edx
0x0000000802147085 <pthread_attr_get_np+1317>:  mov    %rbx,%rsi
0x0000000802147088 <pthread_attr_get_np+1320>:  mov    $0x2,%edi
0x000000080214708d <pthread_attr_get_np+1325>:  callq  0x80213b0dc <__sys_sigprocmask@plt>
0x0000000802147092 <pthread_attr_get_np+1330>:  jmp    0x80214701d <pthread_attr_get_np+1213>
0x0000000802147094 <pthread_attr_get_np+1332>:  lea    0xd79(%rip),%rsi        # 0x802147e14 <__error+2372>
0x000000080214709b <pthread_attr_get_np+1339>:  mov    $0xfffffffffffffffe,%rdi
0x00000008021470a2 <pthread_attr_get_np+1346>:  callq  0x80213b2ec <dlsym@plt>
0x00000008021470a7 <pthread_attr_get_np+1351>:  test   %rax,%rax
0x00000008021470aa <pthread_attr_get_np+1354>:  je     0x802147113 <pthread_attr_get_np+1459>
0x00000008021470ac <pthread_attr_get_np+1356>:  lea    0x80(%rsp),%rsi
0x00000008021470b4 <pthread_attr_get_np+1364>:  mov    %rax,%rdi
0x00000008021470b7 <pthread_attr_get_np+1367>:  callq  0x80213b25c <dladdr@plt>
0x00000008021470bc <pthread_attr_get_np+1372>:  test   %eax,%eax
0x00000008021470be <pthread_attr_get_np+1374>:  je     0x802147113 <pthread_attr_get_np+1459>
0x00000008021470c0 <pthread_attr_get_np+1376>:  mov    0x80(%rsp),%rdi
(gdb) x/s 0x802147e14
0x802147e14 <__error+2372>:      "_Unwind_ForcedUnwind"