It may certainly be something that is not windows specific but just more
likely to crash on windows, and it may be something that is not dependent on
a specific version of SDL but a certain version made it more likely.
However, SDL version and wndows OS make a huge difference regardless.
I wrote an agressive blit to self testing script that exercises in-memory
surfaces and the screen both
It never crashed or showed weird behavior at all on my Mac ever, and I ran
it a bunch.
On my PC though, it never crashed for SDL 1.2.7 through 1.2.9
For SDL 1.2.10 and 1.2.11 it crashes for me after like 2-6 passes, and it
crashes in the blit from surface to screen
for SDL 1.2.12 and 1.2.13 it crashes immediately on first blit of a surface
to itself, everytime
Also, the way it's exhibiting itself on my machine is definitely a crash
inside SDL's blit (I rebuilt pygame with some prints that prove it) as
opposed to SDL stomping stuff then pygame being messed up when it returns.
It's always a pygame parachute segfault for me as well.
So I really do think that I could get a meaningful crash out of this if the
pygame parachute thing wasn't catching the segfault....
So what is it that makes that pygame parachute thing happen? How do I turn
it off? it seems getting a minidump would be preferrable to swallowing the
error like the parachute thing does....
On Sun, Aug 3, 2008 at 9:22 AM, Lenard Lindstrom <[EMAIL PROTECTED]> wrote:
> Like previous segfault bugs this one may not be Windows specific. Windows
> is just more sensitive to invalid memory accesses. Here's what happened when
> I ran the test case interatively:
>
> Python 2.5.2 (r252:60911, Feb 21 2008, 13:11:45) [MSC v.1310 32 bit
> (Intel)] on
> win32
> Type "help", "copyright", "credits" or "license" for more information.
> >>> import pygame
> >>> pygame.init()
> (6, 0)
> >>> a = pygame.Surface((10,10))
> >>> a.blit(a, (0, 0))
> Fatal Python error: Inconsistent interned string state.
>
>
> Not a Pygame parachute but a Python integrity check failure. It all depends
> on where the surface memory is allocated relative to everything else. A
> backtrace of the stack won't help here as the damage was done before the
> error was detected. And it is unclear that the bug is SDL 1.2.13 specific.
> SDL 1.2.13 may simple contribute to the conditions that make the bug
> obvious.
>
> Lenard
>
>
>
import pygame
import random
import math
import sys
print pygame.get_sdl_version()
screen = pygame.display.set_mode((800,600))
num_runs = 100
scroll_step = 100
for i in xrange(num_runs):
print "pass",i
test_width = random.randint(10,400)
test_height = random.randint(10,400)
a = pygame.Surface((test_width, test_height))
a.fill((random.randint(0,255), random.randint(0,255), random.randint(0,255)))
try:
pygame.draw.line(a, (255,255,255), (0,0), (test_width, test_height), 10)
except:
pass
print "blitting surface to self"
sys.stdout.flush()
a.blit(a, (random.randint(-test_width, test_width), random.randint(-test_height, test_height)))
angle = (2.0*math.pi*i)/num_runs
step = (math.cos(angle)*scroll_step, math.sin(angle)*scroll_step)
print "blitting screen to self"
sys.stdout.flush()
screen.blit(screen, step)
print "blitting surface to screen"
sys.stdout.flush()
screen.blit(a, (random.randint(-test_width, 800), random.randint(-test_height, 600)))
pygame.event.get()
pygame.display.flip()
