After i run Slime on Emacs, using ECL as inferior-lisp-program, i see a lot of type conversion errors from gcc. When i post it on ecl bug-tracker, them answers:
Slime contains lisp code that is executed by the different Common Lisp implementations. Unfortunately the slime port for ECL has been out of date for quite some time. Patches were submitted to the Slime maintainers and so far it seems they work, but they might only be available in CVS. Please do not report Slime problems here, but to the Slime mailing list. If _they_ find out it is _not_ a Slime problem, then bug reports will be accepted here.
Full slime output can be downloaded from here http://sourceforge.net/tracker/download.php?group_id=30035&atid=398053&a...
I have last versions of ECL (from GIT) and Slime (from CVS), and upgrade them every day. Emacs-22.3 System x86_64 GNU/Linux. Gentoo.