I want to run a test suite on an implementation I'm not currently working in. For example, TEST-OP could take an :IMPLEMENTATION argument (with one possible value being :ALL to test all "registered" implementations -- whatever "registered" means.)
Fare nicely collected sexps describing how to do that for different implementations at
http://common-lisp.net/gitweb?p=projects/xcvb/xcvb.git;a=blob;f=lisp-invocat...
This is logged as
https://bugs.launchpad.net/asdf/+bug/479513
-T.