[Gdb] Re: cannot debug any threaded/fork program

[Ricardo Nabinger Sanchez]

Quoting  Ricardo Nabinger Sanchez <address@hidden>
Sent on  Tue, 24 Aug 2004 17:47:25 -0300

> I'm trying to debug a program which has 3 threads (pthreads).  the main
> problem is that gdb doesn't detect the threads, althought it stops if I
> set a breakpoint and some of the threads reach it, but then gdb seems to
> lost control and the debugging session gets unreliable.

additionally, if I rearrange my code in order to the main process do the
thread creation and then go to the point I want do debug, I fall into this:

Program received signal SIGTRAP, Trace/breakpoint trap.
0x400d32e1 in sigpending () from /lib/libc.so.6
(gdb)

continuing under these conditions isn't of much help, as gdb doesnt catch
anything else.


also, should gdb detect thread creations via clone() ?  I think so, because
libpthread do that, but in the following example (from Linus) no gdb I've
used detected the new threads:

        http://www.tldp.org/FAQ/Threads-FAQ/clone.c

I've tried gdb versions 5.1, 5.3, 6.1 and 6.2 on differents glibc/gcc
combinations.  I'm not sure about the thread support, but as I receive the
"Using host libthread_db library" I'll assume it is working properly.

I'm trying to get some time to debug gdb, I hope I can handle it :)

thanks again.

-- 
Ricardo Nabinger Sanchez
GNU/Linux #140696 [http://counter.li.org]
Slackware Linux + FreeBSD

  Measure with a micrometer.  Mark with chalk.  Cut with an axe.