------- Comment #2 from freddyz77 at tin dot it 2006-01-06 09:14 -------
Well, I don't know why but looking more deeply I still don't understand
$ gdb /opt/gcc42/libexec/gcc/i686-pc-linux-gnu/4.2.0/cc1
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This GDB was configured as "i386-redhat-linux-gnu"...Using host libthread_db
library "/lib/libthread_db.so.1".
(gdb) r --help
Starting program: /opt/gcc42/libexec/gcc/i686-pc-linux-gnu/4.2.0/cc1 --help
Reading symbols from shared object read from target memory...done.
Loaded system supplied DSO at 0xb9f000
The following options are language-independent:
Program received signal SIGSEGV, Segmentation fault.
0x083580bd in print_filtered_help (flag=536870912) at ../.././gcc/opts.c:1301
1301 memset (printed, 0, cl_options_count);
(gdb) list
1296 if (flag == CL_COMMON || flag == CL_TARGET)
1297 {
1298 filter = flag;
1299 if (!printed)
1300 printed = xmalloc (cl_options_count);
1301 memset (printed, 0, cl_options_count);
1302 }
1303 else
1304 {
1305 /* Don't print COMMON options twice. */
(gdb) info registers
eax 0x9aeb988 162445704
ecx 0x9aeb980 162445696
edx 0x0 0
ebx 0x24e 590
esp 0xbfbaa5b0 0xbfbaa5b0
ebp 0xbfbab9a0 0xbfbab9a0
esi 0x0 0
edi 0x20400001 541065217
eip 0x83580bd 0x83580bd
eflags 0x10246 66118
cs 0x73 115
ss 0x7b 123
ds 0x7b 123
es 0x7b 123
fs 0x0 0
gs 0x33 51
(gdb) disas 0x83580bd
Dump of assembler code for function print_filtered_help:
0x08357f40 <print_filtered_help+0>: push %ebp
0x08357f41 <print_filtered_help+1>: push %edi
0x08357f42 <print_filtered_help+2>: push %esi
0x08357f43 <print_filtered_help+3>: push %ebx
...
0x083580aa <print_filtered_help+362>: je 0x83581a5
<print_filtered_help+613>
0x083580b0 <print_filtered_help+368>: mov 0x85a641c,%ebx
0x083580b6 <print_filtered_help+374>: mov 0x85f5940,%eax
0x083580bb <print_filtered_help+379>: xor %edx,%edx
0x083580bd <print_filtered_help+381>: mov %ebx,0x85a641c
0x083580c3 <print_filtered_help+387>: mov %ebx,0x8(%esp)
0x083580c7 <print_filtered_help+391>: mov %edx,0x4(%esp)
0x083580cb <print_filtered_help+395>: mov %eax,(%esp)
0x083580ce <print_filtered_help+398>: call 0x8049afc
0x083580d3 <print_filtered_help+403>: test %ebx,%ebx
0x083580d5 <print_filtered_help+405>: je 0x8358081
<print_filtered_help+321>
0x083580d7 <print_filtered_help+407>: mov 0x10(%esp),%edx
0x083580db <print_filtered_help+411>: mov %edx,0x14(%esp)
0x083580df <print_filtered_help+415>: xor %esi,%esi
0x083580e1 <print_filtered_help+417>: xor %ebx,%ebx
0x083580e3 <print_filtered_help+419>: jmp 0x83580f1
<print_filtered_help+433>
0x083580e5 <print_filtered_help+421>: inc %esi
0x083580e6 <print_filtered_help+422>: add $0x1c,%ebx
0x083580e9 <print_filtered_help+425>: cmp 0x85a641c,%esi
0x083580ef <print_filtered_help+431>: je 0x8358081
<print_filtered_help+321>
0x083580f1 <print_filtered_help+433>: mov 0x85a642c(%ebx),%edx
0x083580f7 <print_filtered_help+439>: mov 0x14(%esp),%eax
...
0x0835814e <print_filtered_help+526>: call 0x804955c
---Type <return> to continue, or q <return> to quit---q
Quit
(gdb) x/4b 0x85a641c
0x85a641c <cl_options_count>: 0x4e 0x02 0x00 0x00
(gdb)
The program stop at memset so why this
mov %ebx,0x85a641c
should happen??? I cannot find any assigment to this variable however assembly
write into this variable...
freddy77
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25636
