gdb breakpoint on pthread_create

Question

I am trying to set a breakpoint in linux in gdb for a program creating threads. I would like to set a breakpoint on thread creation, but unfortunately pthread_create is a versioned symbol, and I can't get its full name.

If I type:

catch thread_start

I get

Catch of thread_start not yet implemented

How is the best way to catch thread creation in gdb for this situation?

Answer 1

Try this:

(gdb) b __pthread_create_2_1

Or build your own GDB with this patch applied.

Or try the latest pre-release GDB here, which should allow you to do "catch syscall clone"

Answer 2

OK, so in case I didn't really understand you, or my first answer wasn't helpful, do this:

(gdb) info func pthread_create
All functions matching regular expression "pthread_create":

Non-debugging symbols:
0x080485e0  pthread_create
0x080485e0  pthread_create@plt
0x00786590  __pthread_create_2_1
0x00786590  pthread_create@@GLIBC_2.1
0x00786ee0  __pthread_create_2_0
0x00786ee0  pthread_create@GLIBC_2.0

Now pick the symbol that you think is the right one, and set a breakpoint there. Don't pick the ones that have "@" in them, but one of the ones that has digits and underscores, such as 1__pthread_create_2_1.