KDE4 fails to load jpg images (Wallpaper, Okular, ...)

[Kringel]

I compiled KDE4 4.7.3 from an up to date ports tree. Now the desktop, kuickshow and okular are unable to load jpg images. The size-information displays "0x0" in the wallpaper gallery of the desktop (but the thumbnails look ok). Svg, png etc. are no problem. Also i can open all the jpg files with Gimp. I suspect some core component (like qt4-imageformats or so) to be the problem. I was unable to find any related problem reports. Does anyone else has this problem?

Unfortunately there are no error messages on the console. So I would have to write a test-program or debug okular or something else to figure out at which point it fails... but hopefully someone already has solved the problem

 

[Kringel]

I started to debug the problem and figured out that x11-toolkits/qt4-gui is the port that provides the image loading functions. After rebuilding it with debug support it worked. Then I rebuilt it without debug options (because the debug version was incompatible with the ports that depended on its non-debug version and I wanted my desktop back) and then it mysteriously worked. I don't know what was wrong the first time. It is strange.