Cog crash on linux

 
uname -a
Linux sig-desktop 2.6.31-14-generic #48-Ubuntu SMP Fri Oct 16 14:04:26
UTC 2009 i686 GNU/Linux


The image i run was not Cog-ready:

sig@sig-desktop:~/cogvm$ ./squeak ~/squeak/NativeBoost.image

Segmentation fault


Smalltalk stack dump:
0xbfa58d68 M GradientFillStyle>scaledAlphaMix:of:with: 2039648948:
a(n) GradientFillStyle
0xbfa58dbc M [] in GradientFillStyle>computePixelRampOfSize:
2039648948: a(n) GradientFillStyle
0xbfa58ddc M SortedCollection(OrderedCollection)>do: 2039649272: a(n)
SortedCollection
0xbfa58e14 I GradientFillStyle>computePixelRampOfSize: 2039648948:
a(n) GradientFillStyle
0xbfa58e38 I [] in GradientFillStyle class>initPixelRampCache
2012018000: a(n) GradientFillStyle class
0xbfa58e68 M LRUCache>at: 2016558228: a(n) LRUCache
0xbfa58e84 M GradientFillStyle>pixelRamp 2039636440: a(n) GradientFillStyle

But this image was not Cog-ready.


Okay, i copied a cog-ready image:

sig@sig-desktop:~/cogvm$ ./squeak ./Squeak4.2-10382-alpha.image
Segmentation fault
sig@sig-desktop:~/cogvm$

What's interesting, that its have about 70% probability to crash
almost instantry, it just blinking a newly-created host window, and
then ending up with segfault.
In another 30% of cases its not crashing immediately and opens a host
window. But once i try do something, like resizing the window,
it crashing.

And what is bad, that i can't even get a stack dump. This is all it prints:

sig@sig-desktop:~/cogvm$ ./squeak ./Squeak4.2-10382-alpha.image
Segmentation fault
sig@sig-desktop:~/cogvm$ ./squeak ./Squeak4.2-10382-alpha.image
Segmentation fault
sig@sig-desktop:~/cogvm$ ./squeak ./Squeak4.2-10382-alpha.image


I tried multiple couple different images:

sig@sig-desktop:~/cogvm$ ./squeak ./PharoCore-1.2-12159.image
Segmentation fault
sig@sig-desktop:~/cogvm$ ./squeak ./PharoCore-1.2-12159.image
Segmentation fault
sig@sig-desktop:~/cogvm$ ./squeak ./PharoCore-1.2-12159.image
Segmentation fault
sig@sig-desktop:~/cogvm$ ./squeak ./PharoCore-1.2-12159.image
Segmentation fault

it starts, but then once i try to do something like clicking a mouse in window,
it crashing.

I am also tried to use gdb to find where the problem , after attaching
to running process:

gdb -p 25413

and continuing:

(gdb) cont
Continuing.

It is then at some moment prints following:

Cannot find user-level thread for LWP 25416: generic error
(gdb) bt
Target is executing.
(gdb) info threads
  2 Thread 0x77857b70 (LWP 25416)  (running)
* 1 Thread 0xb78976c0 (LWP 25413)  (running)

At that moment VM no longer responsive , while gdb still thinks that
it running..
weird.

--
Best regards,
Igor Stasenko AKA sig.

 
I am also rebuilt VM with full debug into (as specified in HowToBuild)
hoping to get some more info, but got the same results :(

Even core dump can't help much:

Core was generated by `./lib/squeak/3.9-7/squeak PharoCore-1.2-12159.image'.
Program terminated with signal 11, Segmentation fault.
#0  0x009012db in ?? ()
(gdb) bt
#0  0x009012db in ?? ()
#1  0x00906fc0 in ?? ()
#2  <signal handler called>
#3  0x00754701 in ?? ()
#4  0x00755470 in ?? ()
#5  0x0074d80e in ?? ()
#6  0x00bec7ee in ?? ()
(gdb) info threads
  2 Thread 12620  0x08085c02 in ?? ()
* 1 Thread 12623  0x009012db in ?? ()


--
Best regards,
Igor Stasenko AKA sig.

 
While prebuilt VM , downloaded from
http://www.mirandabanda.org/files/Cog/VM/VM.r2316/coglinux.tgz

works well.
Any comments on this issue?

I am currently upgrading my ubuntu install.
Maybe with newer gdb i can at least see where it segfaults.


--
Best regards,
Igor Stasenko AKA sig.

 
Okay, i found where the problem (if anyone interested).

A HowToBuild file says use following command to configure it:
../../platforms/unix/config/configure CFLAGS="-g -O2 -msse2
-D_GNU_SOURCE -DNDEBUG -DITIMER_HEARTBEAT=1 -DNO_VM_PROFILE=1
-DCOGMTVM=0 -DDEBUGVM=0" LIBS=-lpthread


The last one "LIBS=-lpthread"
caused repeating -lpthread twice in makefiles:

LIBS=           -lutil -ldl -lpthread -lm -lnsl -lpthread

Interesting that it builds w/o any errors/warnings,
but crashing soon after few interactions after image startup.
And i think this was the source of gdb confusion as well.

So, the solution is simply NOT put "LIBS=-lpthread" in configure command.

P.S. now, please repeat it for me again: C is better than ...XYZ ? :)

--
Best regards,
Igor Stasenko AKA sig.

 
Thanks, Igor.  I'm integrating this advice into unixbuild/HowToBuild.