Steel Bank Common Lisp

I was curious if SBCL built w/o unicode would be better for
performance and/or memory usage. However, when I modified my
customize-target-features.lisp to disable :sb-unicode and compile, I
get the error trace shown at the end of this message.

This error happens with both sbcl-1.0.42.0 and with the latest sbcl
from git. The platform is x86 Ubuntu 10.04. If I do not disable
:sb-unicode, the build succeeds.

My customize-target-features.lisp has:

(lambda (features)
  (flet ((enable (x)
           (pushnew x features))
         (disable (x)
           (setf features (remove x features))))
    ;; Threading support.
    (enable :sb-thread)
    ;; Disable unicode
    (disable :sb-unicode)))


Error trace:

unhandled SIMPLE-ERROR in thread #<SB-THREAD:THREAD "initial thread" RUNNING
                                   {A9F5F09}>:
  FAILURE-P was set when creating
"obj/from-xc/src/code/external-formats/enc-basic.lisp-obj".

0: (SB-DEBUG::MAP-BACKTRACE #<CLOSURE (LAMBDA #) {B9499FD}>)[:EXTERNAL]
1: (SB-DEBUG:BACKTRACE 128 #<SYNONYM-STREAM :SYMBOL SB-SYS:*STDERR* {90C08F9}>)
2: (SB-DEBUG::DEBUGGER-DISABLED-HOOK
    #<SIMPLE-ERROR "FAILURE-P was set when creating ~S." {B9483F1}>
    #<unavailable argument>)
3: (SB-DEBUG::RUN-HOOK
    SB-EXT:*INVOKE-DEBUGGER-HOOK*
    #<SIMPLE-ERROR "FAILURE-P was set when creating ~S." {B9483F1}>)
4: (INVOKE-DEBUGGER
    #<SIMPLE-ERROR "FAILURE-P was set when creating ~S." {B9483F1}>)
5: (ERROR #<SIMPLE-ERROR "FAILURE-P was set when creating ~S."
{B9483F1}>)[:EXTERNAL]
6: (COMPILE-STEM
    "src/code/external-formats/enc-basic"
    (:NOT-HOST)
    :TARGET-COMPILE)
7: (IN-TARGET-CROSS-COMPILATION-MODE #<CLOSURE (LAMBDA #) {BA8CFD5}>)
8: ((LAMBDA ()))
9: (SB-INT:SIMPLE-EVAL-IN-LEXENV
    (LET ((REVERSED-TARGET-OBJECT-FILE-NAMES NIL))
      (DO-STEMS-AND-FLAGS (STEM FLAGS)
        (UNLESS (POSITION :NOT-TARGET FLAGS)
          (PUSH # REVERSED-TARGET-OBJECT-FILE-NAMES)))
      (SETF *TARGET-OBJECT-FILE-NAMES*
              (NREVERSE REVERSED-TARGET-OBJECT-FILE-NAMES)))
    #<NULL-LEXENV>)
10: (SB-FASL::LOAD-AS-SOURCE
     #<SB-SYS:FD-STREAM
       for "file
/home/ag/downloads/cl/tmp/sbcl-1.0.42/src/cold/compile-cold-sbcl.lisp"
       {BBD9D11}>
     NIL
     NIL)
11: ((FLET SB-FASL::LOAD-STREAM)
     #<SB-SYS:FD-STREAM
       for "file
/home/ag/downloads/cl/tmp/sbcl-1.0.42/src/cold/compile-cold-sbcl.lisp"
       {BBD9D11}>
     NIL)
12: (LOAD "src/cold/compile-cold-sbcl.lisp")[:EXTERNAL]
13: (SB-INT:SIMPLE-EVAL-IN-LEXENV
     (LOAD "src/cold/compile-cold-sbcl.lisp")
     #<NULL-LEXENV>)
14: (SB-EXT:INTERACTIVE-EVAL (LOAD
"src/cold/compile-cold-sbcl.lisp"))[:EXTERNAL]
15: (SB-IMPL::REPL-FUN NIL)
16: ((LAMBDA ()))
17: (SB-IMPL::%WITH-REBOUND-IO-SYNTAX #<CLOSURE (LAMBDA #) {A9F830D}>)
18: (SB-IMPL::TOPLEVEL-REPL NIL)
19: (SB-IMPL::TOPLEVEL-INIT)
20: ((LABELS SB-IMPL::RESTART-LISP))

unhandled condition in --disable-debugger mode, quitting
deleted #P"/home/ag/downloads/cl/tmp/sbcl-1.0.42/obj/from-xc/src/code/external-formats/enc-basic.lisp-obj-tmp"
Command exited with non-zero status 1
114.23user 2.82system 1:57.45elapsed 99%CPU (0avgtext+0avgdata
353744maxresident)k
0inputs+40528outputs (0major+586567minor)pagefaults 0swaps