pantasks gives a Bus Error on my Mac OS 10.5.4 PowerPC

[Michael Wood-Vasey]

[wwoodvas@serenity simtest] gdb which pantasks
GNU gdb 6.3.50-20050815 (Apple version gdb-768) (Tue Oct 2 04:11:19 UTC 2007)
Copyright 2004 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB. Type "show warranty" for details.This GDB was configured as "powerpc-apple-darwin"...Reading symbols for shared libr
aries .............. done

(gdb) run
Starting program: /Volumes/data/PS1/code/ipp-2.6.beta/default.darwin/bin/pantasks Reading symbols for shared libraries +++++++++++++....warning: Could not find object file "/sw/src/fink.build/gcc43-4.3.0-1001/darwin_objdir/powerpc-apple-darwin9/libgcc/_muldi3_s.o" - no debug information available for "../../../gcc-4.3.0/libgcc/..
/gcc/libgcc2.c".

[...]warning: Could not find object file "/sw/src/fink.build/gcc43-4.3.0-1001/darwin_objdir/powerpc-apple-darwin9/libgcc/emutls_s.o" - no debug information available for "
../../../gcc-4.3.0/libgcc/../gcc/emutls.c".

. done

Program received signal EXC_BAD_ACCESS, Could not access memory.
Reason: KERN_INVALID_ADDRESS at address: 0x73000000
[Switching to process 19848 thread 0x117]
0x96371cc4 in strcmp ()
(gdb) bt
#0 0x96371cc4 in strcmp ()#1 0x00051248 in get_variable_ptr (name=0x77c88 "PANTASKS_SERVER_STDERR") at /Volu
mes/data/PS1/src/ipp-2.6.beta/Ohana/src/opihi/lib.shell/VariableOps.c:165#2 0x00051318 in get_variable (name=0x77c88 "PANTASKS_SERVER_STDERR") at /Volumes/
data/PS1/src/ipp-2.6.beta/Ohana/src/opihi/lib.shell/VariableOps.c:179#3 0x0004dac8 in VarConfig (keyword=0x77c88 "PANTASKS_SERVER_STDERR", mode=0x77c84 "%s", ptr=0xf0102dfc) at /Volumes/data/PS1/src/ipp-2.6.beta/Ohana/src/opihi/lib.sh
ell/ConfigInit.c:34#4 0x00002888 in CheckJobsThread (data=0x0) at /Volumes/data/PS1/src/ipp-2.6.beta/
Ohana/src/opihi/pantasks/job_threads.c:25
#5 0x963ab65c in _pthread_start ()
(gdb) up
#1 0x00051248 in get_variable_ptr (name=0x77c88 "PANTASKS_SERVER_STDERR") at /Volumes/data/PS1/src/ipp-2.6.beta/Ohana/src/opihi/lib.shell/VariableOps.c:165
165 if (!strcmp(name, variables[i].name)) {
(gdb) p name
$1 = 0x77c88 "PANTASKS_SERVER_STDERR"
(gdb) p variables
$2 = (Variable *) 0x500b30
(gdb) p i
$3 = 7
(gdb) p variables[i]
$4 = {

name = 0x500970 "KAPA",
value = 0x500980 "kapa"

}
(gdb) p variables[i].name
$5 = 0x500970 "KAPA"
(gdb) p (int) strcmp(name, variables[i].name)
$6 = 5
(gdb) p ! (int) strcmp(name, variables[i].name)
$7 = 0

---

But yet it gave a bus error from within 'strcmp'? I don't understand.

[Michael Wood-Vasey]

This may have been due to a missing 'site.config' file. I would suggest that it possible something be set up to detect missing configuration files more cleanly than this.

Once I installed the site.config file, 'pantasks' seemed to work, although I occasionally, but not repeatedly, get seg faults when launching 'pantasks'. Most of the time I don't though.

[eugene]

i'd be surprised if this really had anything to do with site.config. pantasks does not use 'site.config'. it sounds like a memory corruption error; it looks like i am not being sufficiently thread safe with the variable handling. I think I know how to prevent this.