Line number of segmentation fault

debugging gcc gdb segmentation-fault
Rohit picture Rohit · Feb 3, 2009 · Viewed 96.5k times · Source

Is there any gcc option I can set that will give me the line number of the segmentation fault?

I know I can:

  1. Debug line by line
  2. Put printfs in the code to narrow down.

Edits:

  1. bt / where on gdb give No stack.
  2. Helpful suggestion

Answer

rck picture rck · Feb 3, 2009

I don't know of a gcc option, but you should be able to run the application with gdb and then when it crashes, type where to take a look at the stack when it exited, which should get you close.

$ gdb blah
(gdb) run
(gdb) where

Edit for completeness:

You should also make sure to build the application with debug flags on using the -g gcc option to include line numbers in the executable.

Another option is to use the bt (backtrace) command.

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