[Vm-dev] Cog crash on linux

[Igor Stasenko]

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


I tried multiple couple different images:

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