Re: Regression tester confusion

[Daniel Jacobowitz <drow@mvista.com>]

On Tue, May 07, 2002 at 12:44:05PM -0700, Geoff Keating wrote:
> > Date: Tue, 07 May 2002 11:27:02 -0700
> > From: Mark Mitchell <mark@codesourcery.com>
> > Content-Disposition: inline
> > 
> > I'm confused.  The regression tester seems to be saying that I broke
> > mips-elf with my recent checkin to rs6000/sysv4.h, which seems odd.
> > 
> > Am I going crazy?
> 
> There's something odd going on with mips-elf gdb.base/interrupt.exp.
> It seems to be failing at random---this is the third time it's
> mysteriously appeared.  The symptoms have been that the .log file
> contains:
> 
> (gdb) PASS: gdb.base/interrupt.exp: call function a second time
> continue
> Continuing.
> PASS: gdb.base/interrupt.exp: continue
> data
> 
> data
> FAIL: gdb.base/interrupt.exp: echo data (timeout)
> end of file
> 
> The gdb testsuite is looking for the 'data' output, which as you can
> see is there, and so the testcase should pass.
> 
> The problem seems to happen only when the machine is under other
> load---specifically, when the machine is trying to update its binutils
> & gdb.  I suspect that dejagnu is not properly matching the regexp
> because the extra activity on the machine is causing it to be given
> the output in two or more pieces.  The kernel and dejagnu versions on
> the two machines (mips-elf is on anubis with a 2.4 kernel, native &
> powerpc are on maat with 2.2) are different; hopefully, soon the
> dejagnu versions will be synchronized, which should help to narrow
> down the problem.
> 
> If anyone's seen this before (especially if you fixed it!),
> I'd be interested to hear about it.

This usually means that the previous DejaGNU command did not explicitly
consume enough input... Although in this case, it looks as if there are
an invalid extra \r\n between the 'data's.

The comment two tests up in interrupt.exp sounds as if there's a known
timing problem here.  Did "call function when asleep" fail, causing the
extra newline to get sent?


-- 
Daniel Jacobowitz                           Carnegie Mellon University
MontaVista Software                         Debian GNU/Linux Developer