Note that the compilation notes are due to code added by macroexpansion not being reachable because it is in non-taken branched and/or because I (return-from ...) before it can be reached. That's clearly a bug in the compiler and/or its support macros, though not the worst one. I believe SBCL used to have the same bug long ago, but I don't remember how they solved it. In other news, after my latest upgrade cleanup, CMUCL can once again hot-upgrade ASDF. But whereas it used to be able to upgrade from 2.015 and later, now it can only upgrade from 2.018 and later. I have no idea why. You can try the following and see some weird thing happen in the guts of PCL, either in perform or some function it calls (maybe output-files): ASDF_UPGRADE_TEST_TAGS="2.017" ASDF_UPGRADE_TEST_METHODS="'load-asdf-lisp'load-asdf-system" ./test/run-tests.sh -u cmucl —♯ƒ • François-René ÐVB Rideau •Reflection&Cybernethics• http://fare.tunes.org Put your hand on a hot stove for a minute, and it seems like an hour. Sit with a pretty girl for an hour, and it seems like a minute. THAT'S relativity. — Albert Einstein