Sorry for the long delay.
> It works now. The problem has apparently been caused by some
> *-loaddefs.el files that have been included into the tar-ball. They
> won't be removed by 'make clean' either. After I removed them
> manually, everything compiled.
I am glad it worked :-)
Anyway, you're right: the cedet tarball contains loaddefs files, and I
agree with you on that they could break the build process if using a
flavor of Emacs different from the one used to create them initially.
As these files can be created from scratch by the build process I
think it is safe to remove them from the tarball. For those who just
want them created (without byte-compiling stuff), it remains possible
to use: "make autoloads".
> In general, 'make clean' doesn't really clean a lot. It also doesn't
> remove the *.elc files for instance.
FYI, from the cedet install directory:
make clean - remove temporary and backup files. Useful to
cleanup things after building.
make clean-autoloads - remove the loaddefs files.
make clean-grammars - remove Elisp files generated from grammars.
make clean-info - remove generated info files.
make clean-elc - remove byte-compiled code.
make clean-all - remove all but base code needed to rebuild.
There is also a "make recompile" useful after updating some .el file.
Thanks for your feedback.