This error message means that you changed the "--prefix" argument in "configure" and you didn't clean the build.
Run "make clean-bin" once
(Another useful command is "make clean-zipfiles" - it cleans the resource zips so they are recreated next time you run make).
Now I checked out a fresh svn version (no update!) and I get the same error :shock:
And now I know why:
The directory variable, which is used to define the install destination, is called libdir. And this is the problem, in linux is libdir /usr/lib. During rpm build "make install" has to redefine the destination paths, because it puts the files into a temporary file tree with a prefix in front of the real path names. make install defines libdir=var/tmp/codeblocks-1.0-0.svn.2133-buildroot/usr/lib (had to cut leading "/" again :? ), so it will be overwritten.
Perhaps only rename the variable to something like pluginlibdir ?
EDIT: I submitted Bug #6654 . I'm testing to patch it, but till now my patches don't work (have to look how autotools work)
EDIT2: I posted this problem in the right forum (SVN version Issues)
http://forums.codeblocks.org/index.php?topic=2539.0