Xcode warning: “Multiple build commands for output file”

Question

I am getting an error like this:

[WARN]Warning: Multiple build commands for output file /Developer/B/Be/build/Release-iphonesimulator/BB.app/no.png

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Answer 1

I'm pretty sure this can be caused by an XCode 4 bug, at least in the cases that I've encountered it in.

It happens if you add multiple language dependent files to the project at the same time. I found this out by looking through the git differences. I did nothing in the commit but add some new localized nib files. But looking back at the difference of the project.pbxproj file it showed a bunch of new duplicate references added for files that were already in the project before. The files it did this too seemed random to me.

I reproduced this same exact behavior multiple times.

Deleting these files from the project does not fix the problem because it only deletes the original reference and leaves the duplicates. The only way to fix it is to go back a commit and start over, or hand edit the project file, which is a really good way to screw it up even more since it's hard to tell which duplicates to remove and you have to do it in a ton of different places.

Xcode 4 is just a huge disappointment for me.