As this is a case where the symptom is not connected to the cause (so
looking at the crash in a debugger may not help much) but it seems the
problem can be reproduced consistently no problem, Maybe this is a
good circumstance for binary search debugging?
getting and building SDL from different SVN revisions may be a great
way to do that. For me, the prebuilt 1.2.9 doesn't crash but the
prebuilt 1.2.10 does (although not on the very first blit to self). If
MingW built SDL's behave that same way, then one could do a binary
search of SDL's built from the revision numbers between the 2 releases
to target things down to a specific code change that made it happen.
likewise the repro behavior of the bug changed from 1.2.11 to 1.2.12,
so a binary search between those revisions may be good to do as well.
Another approach other than using SVN revisions is commenting out
functionality (so making it so only half of the code needed to do blit
to self executes, and seeing if the crash still happpens). Of course
that makes blit-to-surface not have the right behavior, and you need
to be a careful about how you comment out, but it can often narrow
down the problem code to a fairly small set.
I'm afraid I can't help with such things at the moment, cause I'm not
setup to build with MingW on windows.
On Tue, Aug 5, 2008 at 7:09 PM, Lenard Lindstrom <len-l@xxxxxxxxx
<mailto:len-l@xxxxxxxxx>> wrote:
The rebuilt SDL.dll still fails. The problem is MinGW related. And
SDL does have code for blitting a surface to itself.
Lenard
Lenard Lindstrom wrote:
I wonder if it is the hermes blit library or some piece of
inlined MMX code. These would not be included in a VC build. I
will build SDL with assembly code turned off and see what happens.