[M3devel] assertion failure in Juno

[Mika Nystrom]

Hello m3devel,

I'm afraid the following is probably an orphan bug, but in case anyone
has a clue what's going on, here it is:

1. Put down three points in Juno, draw a curve using them (looping from
one point back to itself, with the other two as control points).

2. Turn on the grid.

3. Move one of the control points around, so it snaps to the grid.

4. Move the other control point to the same spot.

What happens on my AMD64_FREEBSD is this:

(323)ginger:~/cm3/scripts>Juno
Xlib:  extension "Generic Event Extension" missing on display "rover:1.0".
Assertion failed: (XLIB_SEQUENCE_COMPARE(dpy->last_request_read, <=, dpy->request)), function process_responses, file xcb_io.c, line 242.
Assertion failed: (XLIB_SEQUENCE_COMPARE(dpy->last_request_read, <=, dpy->request)), function process_responses, file xcb_io.c, line 242.
Abort
(324)ginger:~/cm3/scripts>

now if it had crashed in Juno's M3 code I wouldn't be concerned, but it
seems to be crashing in X code, which just sounds wrong... and it seems
to crash in some sort of messaging queue code?  

    Mika

P.S. More detail:

(m3gdb) run
Starting program: /usr/local/cm3/bin/Juno 
Can't disable VM GC.
Signal        Stop      Print   Pass to program Description
SIG64         No        No      Yes             Real-time event 64

Program received signal SIGUSR2, User defined signal 2.
0x0000000802eb729c in __error () from /lib/libthr.so.3
(m3gdb) handle SIGUSR2 nostop noprint
Signal        Stop      Print   Pass to program Description
SIGUSR2       No        No      Yes             User defined signal 2
(m3gdb) cont
Continuing.
Xlib:  extension "Generic Event Extension" missing on display "rover:1.0".
Assertion failed: (XLIB_SEQUENCE_COMPARE(dpy->last_request_read, <=, dpy->request)), function process_responses, file xcb_io.c, line 242.
Assertion failed: (XLIB_SEQUENCE_COMPARE(dpy->last_request_read, <=, dpy->request)), function process_responses, file xcb_io.c, line 242.

Program received signal SIGABRT, Aborted.
0x000000080300ea9c in thr_kill () from /lib/libc.so.7
(m3gdb) where
#0  0x000000080300ea9c in thr_kill () from /lib/libc.so.7
#1  0x000000080309df8b in abort () from /lib/libc.so.7
#2  0x0000000803085f55 in __assert () from /lib/libc.so.7
#3  0x0000000802ba7451 in process_responses () from /usr/local/lib/libX11.so.6
#4  0x0000000802ba7cc7 in _XEventsQueued () from /usr/local/lib/libX11.so.6
#5  0x0000000802b91b8b in XEventsQueued () from /usr/local/lib/libX11.so.6
#6  0x0000000801268b1b in AdjustCoverage (xcon=Invalid C/C++ type code 26 in symbol table.
) at ../src/xvbt/XClientF.m3:362
#7  0x000000080124dfb5 in Messenger (self=Invalid C/C++ type code 26 in symbol table.
) at ../src/xvbt/XMessenger.m3:108
#8  0x0000000801aeb7b3 in RunThread (me=Invalid C/C++ type code 29 in symbol table.
) at ../src/thread/PTHREAD/ThreadPThread.m3:509
#9  0x0000000801aeb569 in ThreadBase (param=Invalid C/C++ type code 35 in symbol table.
) at ../src/thread/PTHREAD/ThreadPThread.m3:490
#10 0x0000000802ead4d1 in pthread_getprio () from /lib/libthr.so.3
#11 0x0000000000000000 in ?? ()
(m3gdb) 
(m3gdb) up 6
#6  0x0000000801268b1b in AdjustCoverage (xcon=16_000000080377a2c0, d=1) at ../src/xvbt/XClientF.m3:362
362         IF X.XEventsQueued(xcon.dpy, X.QueuedAfterReading) # 0 THEN
Current language:  auto; currently Modula-3
(m3gdb) list
357       RAISES {TrestleComm.Failure} =
358       BEGIN
359         TRY
360         INC(xcon.coverage, d);
361         IF xcon.coverage = 0 THEN X.XFlush(xcon.dpy) END;
362         IF X.XEventsQueued(xcon.dpy, X.QueuedAfterReading) # 0 THEN
363           Thread.Signal(xcon.qNonEmpty)
364         END;
365         EXCEPT X.Error => RAISE TrestleComm.Failure END;
366       END AdjustCoverage;
(m3gdb) print xcon.dpy
$1 = 16_000000080389f000