[Qgis-developer] OSX Snow Leopard update & notes

[William Kyngesburye]

I updated the Xcode project to work with Snow Leopard.  That means  
adding a "snow" SDKSYS and working around some issues in Snow.

For all OSX versions, I removed the "native" build (SDKSYS not set).   
All compilation uses the system SDK that you are building for.

Also for all versions, I made Python and Expat defaults based on the  
SDKSYS.  They both will use system-provided versions by default, if  
available.


Some general Snow Leopard notes:

- the default GCC version is now 4.2.  This could be trouble if mixed  
with libraries compiled with 4.0 (ie Qt binaries).  At least Qgis  
didn't crash, I haven't tried using it yet.

- Qt 4.5 doesn't officially support Snow yet, but it seems to be  
working.  Every Qgis source compiled will spew a warning:

#warning "Support for this version of Mac OS X is still preliminary"

- SIP/PyQt need some fixes, but it's not difficult.  A big problem is  
that the Python executable is now 64bit (!), but Qt (standard) is  
still 32bit only, so you need to force it to run 32bits so that SIP  
and PyQt configuration and tools work properly. (ie pyuic4 is a shell  
script that runs the pyuic python script)  And the arch command is  
broken, so it's not simple.

When everything is working smoothly, I'll look into Qt Cocoa.

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

All generalizations are dangerous, even this one.