Building SBCL with ABCL

In revisiting our compiler for various improvements, it is helpful to have challenging compilations to perform so that we have some confidence we don't break things along the way. One of the more complicated tasks we've found is using ABCL as a build host to compile SBCL which has seemingly has lots of twisty little macros, all different. A while ago, maybe perhaps a year ago, we broke this behavior, closing off this avenue of testing.

But due to recent work, as of ABCL trunk r13538 we've restored this capability, once again making ABCL capable of bootstrapping an SBCL build. This may prove handy for individuals who wish to port SBCL to new platforms where there is a JVM available.

When we mentioned this on #lisp, we were asked how long it takes ABCL to build SBCL vs. SBCL building itself.

ABCL building SBCL

//build started:  Thu Aug 25 15:12:30 CEST 2011

//build finished: Thu Aug 25 16:49:30 CEST 2011

real	96m59.819s

user	37m35.702s

sys	32m44.641s

SBCL building SBCL

//build started:  Thu Aug 25 16:51:34 CEST 2011

//build finished: Thu Aug 25 17:07:47 CEST 2011

real	16m12.855s

user	4m40.804s

sys	3m28.145s

So, ABCL is roughly a factor of six slower building SBCL than SBCL itself.