Re: Can't debug multithreaded apps on mips-sgi-irix-6.5

[Andrew Cagney]

So that people know about this problem, can I suggest creating a 
change-request describing it.  See:

http://sources.redhat.com/gdb/bugs/

As David suggests, someone adding support for this would be great as 
well.  If you're interested and don't have an FSF assignment (or don't 
know what one is) let me know.

Andrew



> Richard Tollerton <address@hidden> writes:
>
> > Environment: SGI Octane (MIPS R10K 64-bit mode) running IRIX 6.5; gcc
> > 3.0.4 with gcc 2.95.3 tested previously. SGI development tools include the
> > MIPSPro 7.3 toolchain. gdb version is 5.1.1 with 5.0 used previously.
> >
> > Description: Any multithreaded app cannot be debugged with gdb; it hangs
> > on application startup. I've tested this with my code (~7000-line Qt C++
> > app), somebody else's GLUT app, and this one-liner test case that doesn't 
> > even use threads:



> Unfortunately, gdb does not yet support IRIX pthreads.
> Even if gdb did not hang the  result would not be useful.
>
> There is a special shared library, libspypt.so, to interact
> with IRIX pthreads and we've not documented the interface 
> nor shipped the headers.  Oops.
> It's unfortunately not like any existing pthreads interface.
> Partly because IRIX pthreads are all *within* one process
> as of IRIX6.5 -- very different than say Linux.
> ptrace is useless for this and /proc required considerable
> extension.
>
> The problem is we just did not get around to shipping or documenting
> anything on this (libspypt.so is shipped, but
> not the headers needed to compile code to interact
> with libspypt.so). 
> This is  not 'secret'.
> We've provided the headers (and some documentation) to
> some people, but that does not yet directly help gdb.
>
> Yes, I'm somewhat embarrassed by this, but
> I have not had time to be any help.
>
> Anyone wishing to volunteer on this will need help
> from us and should contact me.
>
> Sorry. At this time your only choices are
> a) try ddd or some other gui that 'hides' the dbx-ness
>    of dbx on IRIX
>    (to the extent such do, I _still_ have not tried ddd)
> b) use dbx or Workshop on IRIX.
>
> Again, sorry. Not what you wanted to hear.
> address@hidden