I've been getting regular illegal instruction coredumps on mac68k
with pthread programs (including named). Looking at the coredumps in
gdb, it seems like something is taking leap to a maybe-random address.
Does anyone else see this on other m68k?

BTW: All this is on a release build from CVS tag netbsd-4, running
on a Apple Macintosh Quadra 605 (with full 68040).

Here's a dump from a program with only two threads:

ksh$ gdb `whence fblckgen` fblckgen.core
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This GDB was configured as "m68k--netbsdelf"...
Core was generated by `fblckgen'.
Program terminated with signal 4, Illegal instruction.
Reading symbols from /usr/lib/libpthread.so.0...done.
Loaded symbols for /usr/lib/libpthread.so.0
Reading symbols from /usr/lib/libc.so.12...done.
Loaded symbols for /usr/lib/libc.so.12
Reading symbols from /usr/libexec/ld.elf_so...done.
Loaded symbols for /usr/libexec/ld.elf_so
#0  0x049ffbe4 in ?? ()
(gdb) thr app all bt

Thread 3 (Thread 22 ()):
#0  0x04023174 in pthread__locked_switch () from /usr/lib/libpthread.so.0
#1  0x06bffb70 in ?? ()
#2  0x040283b2 in pthread_cond_wait () from /usr/lib/libpthread.so.0
#3  0x0000353e in makeBlocks (dummy=0x0) at fblckgen.c:234
#4  0x040296ec in pthread_create () from /usr/lib/libpthread.so.0

Thread 2 (LWP 2):
#0  0x040584c2 in write () from /usr/lib/libc.so.12
#1  0x04022fca in write () from /usr/lib/libpthread.so.0
#2  0x000031be in main (argc=131072, argv=0x0) at fblckgen.c:179

Thread 1 (LWP 1):
#0  0x049ffbe4 in ?? ()
#1  0x040283b2 in pthread_cond_wait () from /usr/lib/libpthread.so.0
#2  0x0000353e in makeBlocks (dummy=0x0) at fblckgen.c:234
#3  0x040296ec in pthread_create () from /usr/lib/libpthread.so.0
#0  0x049ffbe4 in ?? ()

Another program, with 3 threads:

ksh$ gdb iohammer iohammer.core.4
...
Core was generated by `iohammer'.
Program terminated with signal 4, Illegal instruction.
...
#0  0x043ffbe4 in ?? ()
(gdb) thr app all bt

Thread 4 (Thread 1 ()):
#0  0x04025174 in pthread__locked_switch () from /usr/lib/libpthread.so.0
#1  0xffffade0 in ?? ()
#2  0x0402a3b2 in pthread_cond_wait () from /usr/lib/libpthread.so.0
#3  0x0000367e in main (argc=0, argv=0x0) at iohammer.c:185

Thread 3 (LWP 1):
#0  0x0405a53e in read () from /usr/lib/libc.so.12
#1  0x04024e4e in read () from /usr/lib/libpthread.so.0
#2  0x00003bf0 in doIO (arg=0x0) at iohammer.c:351
#3  0x0402b6ec in pthread_create () from /usr/lib/libpthread.so.0

Thread 2 (LWP 2):
#0  0x0405a53e in read () from /usr/lib/libc.so.12
#1  0x04024e4e in read () from /usr/lib/libpthread.so.0
#2  0x00003bf0 in doIO (arg=0x1) at iohammer.c:351
#3  0x0402b6ec in pthread_create () from /usr/lib/libpthread.so.0

Thread 1 (LWP 3):
#0  0x043ffbe4 in ?? ()
#0  0x043ffbe4 in ?? ()

And finally, named:

ksh$ sudo gdb /usr/sbin/named /etc/namedb/named.core
...
Core was generated by `named'.
Program terminated with signal 4, Illegal instruction.
Reading symbols from /usr/lib/libpthread.so.0...(no debugging symbols found)...
done.
Loaded symbols for /usr/lib/libpthread.so.0
Reading symbols from /usr/lib/libcrypto.so.3...(no debugging symbols found)...
done.
Loaded symbols for /usr/lib/libcrypto.so.3
Reading symbols from /usr/lib/libc.so.12...(no debugging symbols found)...done.
Loaded symbols for /usr/lib/libc.so.12
Reading symbols from /lib/libcrypt.so.0...(no debugging symbols found)...done.
Loaded symbols for /lib/libcrypt.so.0
Reading symbols from /usr/libexec/ld.elf_so...(no debugging symbols found)...
done.
Loaded symbols for /usr/libexec/ld.elf_so
#0  0x049ff808 in ?? ()
(gdb) thr app all bt

Thread 5 (Thread 23 ()):
#0  0x04147174 in pthread__locked_switch () from /usr/lib/libpthread.so.0
#1  0x06fffb68 in ?? ()
#2  0x0414c3b2 in pthread_cond_wait () from /usr/lib/libpthread.so.0
#3  0x000f10bc in isc_timer_detach ()
#4  0x0414d6ec in pthread_create () from /usr/lib/libpthread.so.0

Thread 4 (LWP 2):
#0  0x042ac51e in select () from /usr/lib/libc.so.12
#1  0x04146f0e in select () from /usr/lib/libpthread.so.0
#2  0x000e537e in isc_socket_detach ()
#3  0x0414d6ec in pthread_create () from /usr/lib/libpthread.so.0

Thread 3 (LWP 4):
#0  0x042d8c12 in __sigtimedwait () from /usr/lib/libc.so.12
#1  0x04148196 in sigtimedwait () from /usr/lib/libpthread.so.0
#2  0x042ad2ec in sigwait () from /usr/lib/libc.so.12
#3  0x000e8fc4 in isc_app_run ()
#4  0x0001596c in main ()
#5  0x000058e4 in __start ()

Thread 2 (LWP 3):
#0  0x00015ffe in ns_query_init ()
#1  0x00008da0 in client_create ()
#2  0x00009c00 in ns_clientmgr_createclients ()
#3  0x0000de14 in ns_interface_listenudp ()
#4  0x0000e062 in ns_interface_setup ()
#5  0x0000e974 in do_scan ()
#6  0x0000ed6a in ns_interfacemgr_scan0 ()
#7  0x0000ede0 in ns_interfacemgr_scan ()
#8  0x0001ebf8 in scan_interfaces ()
#9  0x0001f6a0 in load_configuration ()
#10 0x000208d6 in run_server ()
#11 0x000fccd6 in isc_task_getcurrenttime ()
#12 0x000fcdf6 in isc_task_getcurrenttime ()
#13 0x0414d6ec in pthread_create () from /usr/lib/libpthread.so.0

Thread 1 (LWP 5):
#0  0x049ff808 in ?? ()
#0  0x049ff808 in ?? ()

Looking now, the PCs of the failing threads are very similar. I've
used PTHREAD_DEBUGLOG, but can't see anything of great meaning
there - anyone have any ideas, before I go digging deeper?

-- 
Paul Ripke