Reported as an 'issue' on the blackhole tracker (http://github.com/pereckerdal/blackhole/issues/#issue/6), but I figured I'd copy it to the list in case anyone else was interested/being-affected, or on the offhand chance that this isn't a responsibility of blackhole to correct for a change in gambit... upgrading to 4.5.3 kills import dead in it's tracks whenever you have a module that uses the C FFI and thus requires compilation. As demonstrated below (only change is upgrade to 4.5.3 and re-build of 'build.scm'/removal of ns.dat) [nikki@vbox src]$ bsc Loaded Black Hole... Gambit v4.5.2
(import test-c) /home/nikki/src/test-c is being compiled... (c-print) Hello world
===== [nikki@vbox src]$ bsc Loaded Black Hole... Gambit v4.5.3
(import test-c) /home/nikki/src/test-c is being compiled... *** ERROR -- Operator is not a PROCEDURE (#("test-c.o1" ##2 <http://github.com/pereckerdal/blackhole/issues/#issue/2> | test-c.o1|>))
At a guess, this is likely caused by something in the following commit : http://www.iro.umontreal.ca/~gambit/repo/.cgit.cgi/Gambit/commit/?id=5bae3cb... <http://www.iro.umontreal.ca/%7Egambit/repo/.cgit.cgi/Gambit/commit/?id=5bae3cb2db90f90ae9fbe16374f4c44fdb3106fe>