Re: Issues with gdb under linux....LOTS of them

[Martin Percossi]

> Have you tried the current GDB sources?  I'm not sure, but I think
> people have been working on the thread handling since 5.0.

I have now installed gdb 5.0. To my pleasant surprise, name mangling, at
least against gcc 2.95 works perfect. Sweet! Now the problem: threading
works worse than in v4. I've tried starting the app from within gdb and
it crashes with a message that will follow shortly. I have also tried to
attach to the process while it is running, and although this allows me
to get (a bit) further, I still crash with the same error message. Here
it is:


Program received signal SIGTRAP, Trace/breakpoint trap.
[Switching to Thread 16401 (runnable)]
0x0 in ?? ()
Current language:  auto; currently c
(gdb) info threads
  22 Thread 20501 (runnable)  0x40a1713e in __clone () from
/lib/libc.so.6
  21 Thread 19476 (runnable)  0x40983dcb in __sigsuspend
(set=0xbd3ffbe8)
    at ../sysdeps/unix/sysv/linux/sigsuspend.c:48
  20 Thread 18451 (runnable)  0x40983dcb in __sigsuspend
(set=0xbd5ffbe8)
    at ../sysdeps/unix/sysv/linux/sigsuspend.c:48
  19 Thread 17426 (runnable)  0x40983dcb in __sigsuspend
(set=0xbd7ffbe8)
    at ../sysdeps/unix/sysv/linux/sigsuspend.c:48
* 18 Thread 16401 (runnable)  0x0 in ?? ()
  17 Thread 15376 (runnable)  0x40a1215e in __select () from
/lib/libc.so.6
  16 Thread 14351 (runnable)  0x40983dcb in __sigsuspend
(set=0xbddffac8)
    at ../sysdeps/unix/sysv/linux/sigsuspend.c:48
  15 Thread 13326 (runnable)  0x40983dcb in __sigsuspend
(set=0xbdfffac8)
    at ../sysdeps/unix/sysv/linux/sigsuspend.c:48
  14 Thread 12301 (runnable)  0x40983dcb in __sigsuspend
(set=0xbe1ffac8)
    at ../sysdeps/unix/sysv/linux/sigsuspend.c:48
  13 Thread 11276 (runnable)  0x40983dcb in __sigsuspend
(set=0xbe3ffac8)
    at ../sysdeps/unix/sysv/linux/sigsuspend.c:48
  12 Thread 10251 (runnable)  0x40983dcb in __sigsuspend
(set=0xbe5ffc48)
    at ../sysdeps/unix/sysv/linux/sigsuspend.c:48
  11 Thread 9226 (runnable)  0x40983dcb in __sigsuspend (set=0xbe7ffc48)
    at ../sysdeps/unix/sysv/linux/sigsuspend.c:48
  10 Thread 8201 (runnable)  0x40983dcb in __sigsuspend (set=0xbe9ffc48)
    at ../sysdeps/unix/sysv/linux/sigsuspend.c:48
  9 Thread 7176 (runnable)  0x40983dcb in __sigsuspend (set=0xbebffc48)
    at ../sysdeps/unix/sysv/linux/sigsuspend.c:48
  8 Thread 6151 (runnable)  0x40983dcb in __sigsuspend (set=0xbedffc48)
    at ../sysdeps/unix/sysv/linux/sigsuspend.c:48
  7 Thread 5126 (runnable)  0x40983dcb in __sigsuspend (set=0xbefffc48)
    at ../sysdeps/unix/sysv/linux/sigsuspend.c:48
  6 Thread 4101 (runnable)  0x40983dcb in __sigsuspend (set=0xbf1ffc48)
    at ../sysdeps/unix/sysv/linux/sigsuspend.c:48
  5 Thread 3076 (runnable)  0x40983dcb in __sigsuspend (set=0xbf3ffc48)
    at ../sysdeps/unix/sysv/linux/sigsuspend.c:48
  4 Thread 2051 (runnable)  0x40983dcb in __sigsuspend (set=0xbf5ffc48)
    at ../sysdeps/unix/sysv/linux/sigsuspend.c:48
  3 Thread 1026 (runnable)  0x40983dcb in __sigsuspend (set=0xbf7ff9b4)
    at ../sysdeps/unix/sysv/linux/sigsuspend.c:48
  2 Thread 2049 (runnable)  0x406477c5 in __linuxthreads_create_event ()
    at events.c:24
  1 Thread 1024 (runnable)  0x40a1215e in __select () from
/lib/libc.so.6

I'm not really sure what a SIGTRAP signal is, but I certainly haven't
placed any breakpoints and haven't interrupted the program. It's strange
because as long as you didn't interrupt the program (w/ ctrl-c) in v4,
the program wouldn't crash. So I'm in the rather frustrating position of
being able to choose between a debugger that demangles C++ like a beauty
but won't load my app and one that loads the app but can't demangle
properly..... unless I can graft the demangling of v5 on the v4 code.
Does anyone know if that would be hard to do? Or better yet, has anyone
seen the problem I have before? All other specs are as in my previous
posting, I will include version info for gdb 5 for completeness below:

GNU gdb 5.0
Copyright 2000 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you
are
welcome to change it and/or distribute copies of it under certain
conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB.  Type "show warranty" for
details.
This GDB was configured as "i686-pc-linux-gnu".

Any help would be greatly appreciated.

TIA
Martin.

-- 
Martin Percossi
Development
RiverSoft Ltd.
address@hidden
Tel. 020 8392 5740 Ext. 5724

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