Re: <EMACS> Re: emacs21.2 freezes on hp when calling visible-bell

[Richard Stallman]

I am amazed that gettimeofday can hang.  I have no idea why.  Perhaps
you need to find an HP wizard for this.  Maybe Bruce Perens can help.

From: Maarten Vergauwen <address@hidden>
Date: Tue, 26 Mar 2002 11:50:38 +0100
To: address@hidden
Subject: Re: <EMACS> Re: emacs21.2 freezes on hp when calling visible-bell
In-Reply-To: <address@hidden>

Richard Stallman writes:
 >     This happens only on hp, using X and only for 21.2. No problems
 >     encountered for 21.1 on hp, nor for 21.2 on hp without X, nor for 21.2
 >     on SGI, linux-i386, alpha, solaris or ultrix with X.
 > 
 > Unfortunately that means I can't even try to debug it.
 > Can you please try to debug it?  etc/DEBUG gives some advice.

OK, here goes.

1. If emacs is run under gdb, it hangs when trying to "flash" the visible
   bell.
2. kill -TSTP pid in another shell
3. gdb tells me that it's hanging in gettimeofday()

(gdb) bt
#0  0x7f7aeac8 in gettimeofday () from /usr/lib/libc.2
#1  0x179948 in alarm_signal_handler (signo=14) at atimer.c:372
#2  <signal handler called>
#3  0x7f794384 in fwrite () from /usr/lib/libc.2
#4  0xd0158 in main (argc=2139029609, argv=0x7f7f061c, envp=0x8)
    at emacs.c:1547

4. I added lots of fprintf(stderr,...) stuff to the code in xterm.c
   (function XTflash) and in this way I could determine that emacs was
   hanging on the line that says: 
            select (0, NULL, NULL, NULL, &timeout);
   A strange thing is that the loop with "select" is sometimes executed 1,
   2, 3  times before it hangs at this line.

5. I reconfigured and recompiled emacs-21.1 on the same system, with the
   same compiler and here the problem doesn't occur.

I'm at a loss here. Could you tell me what else I could try to find the
source of the problem ?


kind regards,

Maarten


-- 
MAARTEN VERGAUWEN
K.U.Leuven - ESAT-PSI   tel: +32-16-32.10.64  fax: +32-16-32.17.23
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