Busy busy busy (yes, with real work, too).

On the other hand, I have had the time to do enough mindless debugging to enable SBCL to build using CLISP as a cross-compilation host.

Remember way back, when we were looking at ensuring that SBCL didn't actually have any leakage from the cross-compilation host to the target code, so that in fact the sources, and not whatever compiler you happened to be compiling the sources on, determined the nature of the resulting executable? Well, OpenMCL was a decent enough first choice, because it was based on mature technology and had a suitably non-painful debugger.

So there wasn't going to be anything terribly fundamental about making it work under CLISP; "mindless debugging", I said. The process did pick up one or two real portability bugs (depending on the initial element of an uninitialized array, for instance); some annoying portability bugs (CLISP gives a full WARNING on function redefinition, which plays havoc with detecting failures), and one real leakage:

CLISP has a value of MOST-POSITIVE-FIXNUM of 16777215, unlike CMUCL, SBCL and OpenMCL which all have a value of 536870911. This lower value was leaking through into some type declarations, which were then erroneously signalling errors. Fixing this made it all worthwhile: now SBCL can build, in a slightly roundabout way, on a system with only gcc installed. Oh, yeah, and several bugs in CLISP were exposed and fixed as a result of this exercise, too.

In other news, SBCL has native threads on x86/Linux. Cool.