Menu
I'm debugging an application write in ansi C, a multiple threads program.
Sometime, in the main thread cause a SIGSEGV fault.
(gdb) backtrace full
#0 0x0000000000000000 in ?? ()
No symbol table info available.
#1 0x0000000000000000 in ?? ()
No symbol table info available.
(gdb) info registers
rax 0x1 1
rbx 0x0 0
rcx 0x0 0
rdx 0x2 2
rsi 0x458e7aa0 1166965408
rdi 0x0 0
rbp 0x0 0x0
rsp 0x458e7b60 0x458e7b60
r8 0x458e7b20 1166965536
r9 0x0 0
r10 0x0 0
r11 0x206 518
r12 0x2aaaac400e70 46912522686064
r13 0x2aaaac514090 46912523813008
r14 0x1 1
r15 0x18505f10 407920400
rip 0x0 0
eflags 0x10206 [ PF IF RF ]
cs 0x33 51
ss 0x2b 43
ds 0x0 0
es 0x0 0
fs 0x63 99
gs 0x0 0
fctrl 0x37f 895
fstat 0x0 0
ftag 0xffff 65535
fiseg 0x0 0
fioff 0x0 0
foseg 0x0 0
fooff 0x0 0
fop 0x0 0
mxcsr 0x1f80 [ IM DM ZM OM UM PM ]
(gdb)
This information is from core file, I'm not very family with debug in Linux environment, Is there anything I can do to find where's the problem?
Edit: all of source files are compiled with flag as follow
gcc -O0 -g3 -Wall -c -fmessage-length=0 -MMD -MP -MF"src/redisconnector.d" -MT"src/redisconnector.d" -o"src/redisconnector.o" "../src/redisconnector.c"
490
A backtrace is a list of the function calls that are currently active in a thread. The usual way to inspect a backtrace of a program is to use an external debugger such as gdb. However, sometimes it is useful to obtain a backtrace programmatically from within a program, e.g., for the purposes of logging or diagnostics.
SigSegV means a signal for memory access violation, trying to read or write from/to a memory area that your process does not have access to. These are not C or C++ exceptions and you can't catch signals.
A backtrace is the series of currently active function calls for the program. Each item in the array pointed to by buffer is of type void *, and is the return address from the corresponding stack frame. The size argument specifies the maximum number of addresses that can be stored in buffer.
Your RIP points to 0. It's probably caused by a stack overflow. Your RBP is also 0, so the backtrace gdb command will tell you nothing.
187
Recompile the application with "-g" option;
Use Gdb not with core files, but to run entire application:
gdb --args ./application application_options
then "run" command of gdb.
Running from gdb will detect SIGSEGV, and gdb will be focused on failed thread.
38
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With
