[Qgis-developer] QGIS crash on Mac OS X -- 0.8 release branch

[William Kyngesburye]

On May 13, 2007, at 2:07 AM, Gary Sherman wrote:

> Qt is installed from the TrollTech framework (dmg).
>
The linking of the Qt frameworks in Qgis was odd, there are no paths  
to the frameworks:

Qt3Support.framework/Versions/4/Qt3Support
...

It should either be an absolute path, or one of the special relative  
paths (@executable_path or a tiger-only one, I can't remember what).

I just installed Qt 4.2.3.  I guess the OSX linker tries to find  
frameworks automatically from the standard locations - Qgis starts  
now.  I symlinked my GRASS.app to the Resources/grass-6.2.1/ location  
used in the plugin/provider, but when I checked to see if the GRASS  
plugin loaded, it hadn't, along with the gpx and wfs providers.

And whadayaknow, open a shapefile and boom.  Not much help in the  
crash log, except to say that it crashed in  
"QgsOgrProvider::loadFields() + 24" with an "EXC_BAD_INSTRUCTION  
(0x0002)". (that might help you more than it helps me figure out  
what's wrong)  The Binary Images section shows that the grass plugin/ 
provider IS loaded, but I guess not in a state usable by Qgis.

Removed the grass plugin/rovider and a shapefile opens.  So, it only  
takes the presence of those to cause it to crash, or maybe that's the  
problem - the GRASS plugin isn't loading when it should, and the  
symptom (crash) is showing up later.

> I installed your (William's) GRASS 6.3-cvs package and now  
> everything seems to work.
> It did not work with the GRASS 6.2 package.
>
huh.  I wonder if just the version numbering is the key.  Just a  
thought, but if GDAL loads its grass 6.2 libs, then Qgis tries to  
load another set of 6.2 libs, the OSX linker may be trying to be  
smart and using one that's already loaded, but they're just different  
enough from what Qgis expects to cause problems.  But with Qgis+GRass  
6.3, the linker sees 6.3 as different enough to load those libraries  
also.

I don't know much about details like this, but it sounds reasonable  
to me.

-----
William Kyngesburye <kyngchaos*at*kyngchaos*dot*com>
http://www.kyngchaos.com/

"This is a question about the past, is it? ... How can I tell that  
the past isn't a fiction designed to account for the discrepancy  
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