linux -> darwin cross-compiler failure (apple gcc 4.0.1-5250 or pristine gcc 4.0.2)

["Benjamin Reed" <rangerrick at gmail dot com>]

I've tried compiling both apple gcc-5250 and gcc-4.0.2 on linux as a
darwin cross-compiler, but I get an identical error:

---(snip!)---
make[2]: Entering directory `/tmp/gcc-4.0.2/builddir/gcc'
/tmp/gcc-4.0.2/builddir/gcc/xgcc -B/tmp/gcc-4.0.2/builddir/gcc/
-B/opt/darwin-cross/powerpc-apple-darwin8.0/bin/
-B/opt/darwin-cross/powerpc-apple-darwin8.0/lib/ -isystem
/opt/darwin-cross/powerpc-apple-darwin8.0/include -isystem
/opt/darwin-cross/powerpc-apple-darwin8.0/sys-include -O2  -DIN_GCC
-DCROSS_COMPILE   -W -Wall -Wwrite-strings -Wstrict-prototypes
-Wmissing-prototypes -Wold-style-definition  -isystem ./include 
-Wa,-force_cpusubtype_ALL -pipe -g -DHAVE_GTHR_DEFAULT -DIN_LIBGCC2
-D__GCC_FLOAT_NOT_NEEDED -Dinhibit_libc -dynamiclib -nodefaultlibs
-Wl,-install_name,/opt/darwin-cross/powerpc-apple-darwin8.0/lib/libgcc_s.1.0.dylib
-Wl,-flat_namespace -o ./libgcc_s.1.0.dylib.tmp
-Wl,-exported_symbols_list,libgcc/./libgcc.map -compatibility_version
1 -current_version 1.0  libgcc/./_muldi3_s.o libgcc/./_negdi2_s.o
libgcc/./_lshrdi3_s.o libgcc/./_ashldi3_s.o libgcc/./_ashrdi3_s.o
libgcc/./_cmpdi2_s.o libgcc/./_ucmpdi2_s.o libgcc/./_floatdidf_s.o
libgcc/./_floatdisf_s.o libgcc/./_fixunsdfsi_s.o
libgcc/./_fixunssfsi_s.o libgcc/./_fixunsdfdi_s.o
libgcc/./_fixdfdi_s.o libgcc/./_fixunssfdi_s.o libgcc/./_fixsfdi_s.o
libgcc/./_fixxfdi_s.o libgcc/./_fixunsxfdi_s.o libgcc/./_floatdixf_s.o
libgcc/./_fixunsxfsi_s.o libgcc/./_fixtfdi_s.o
libgcc/./_fixunstfdi_s.o libgcc/./_floatditf_s.o
libgcc/./_clear_cache_s.o libgcc/./_enable_execute_stack_s.o
libgcc/./_trampoline_s.o libgcc/./__main_s.o libgcc/./_absvsi2_s.o
libgcc/./_absvdi2_s.o libgcc/./_addvsi3_s.o libgcc/./_addvdi3_s.o
libgcc/./_subvsi3_s.o libgcc/./_subvdi3_s.o libgcc/./_mulvsi3_s.o
libgcc/./_mulvdi3_s.o libgcc/./_negvsi2_s.o libgcc/./_negvdi2_s.o
libgcc/./_ctors_s.o libgcc/./_ffssi2_s.o libgcc/./_ffsdi2_s.o
libgcc/./_clz_s.o libgcc/./_clzsi2_s.o libgcc/./_clzdi2_s.o
libgcc/./_ctzsi2_s.o libgcc/./_ctzdi2_s.o libgcc/./_popcount_tab_s.o
libgcc/./_popcountsi2_s.o libgcc/./_popcountdi2_s.o
libgcc/./_paritysi2_s.o libgcc/./_paritydi2_s.o libgcc/./_powisf2_s.o
libgcc/./_powidf2_s.o libgcc/./_powixf2_s.o libgcc/./_powitf2_s.o
libgcc/./_mulsc3_s.o libgcc/./_muldc3_s.o libgcc/./_mulxc3_s.o
libgcc/./_multc3_s.o libgcc/./_divsc3_s.o libgcc/./_divdc3_s.o
libgcc/./_divxc3_s.o libgcc/./_divtc3_s.o libgcc/./_divdi3_s.o
libgcc/./_moddi3_s.o libgcc/./_udivdi3_s.o libgcc/./_umoddi3_s.o
libgcc/./_udiv_w_sdiv_s.o libgcc/./_udivmoddi4_s.o
libgcc/./darwin-tramp_s.o libgcc/./darwin-ldouble_s.o
libgcc/./unwind-dw2_s.o libgcc/./unwind-dw2-fde-darwin_s.o
libgcc/./unwind-sjlj_s.o libgcc/./unwind-c_s.o
libgcc/./darwin-fallback_s.o -lc && rm -f ./libgcc_s.dylib && if [ -f
./libgcc_s.1.0.dylib ]; then mv -f ./libgcc_s.1.0.dylib
./libgcc_s.1.0.dylib.backup; else true; fi && mv
./libgcc_s.1.0.dylib.tmp ./libgcc_s.1.0.dylib && ln -s
libgcc_s.1.0.dylib ./libgcc_s.dylib
xgcc: installation problem, cannot exec '/usr/bin/libtool': No such
file or directory
make[2]: *** [libgcc_s.dylib] Error 1
make[2]: Leaving directory `/tmp/gcc-4.0.2/builddir/gcc'
make[1]: *** [libgcc.a] Error 2
make[1]: Leaving directory `/tmp/gcc-4.0.2/builddir/gcc'
make: *** [all-gcc] Error 2
---(snip!)---

Obviously it's looking for apple's libtool.  It seems like I shouldn't
be making a libgcc_s.dylib anyways since I only care about making .o's
for distcc, and not linking whole binaries, but, If I change
gcc/config/darwin.h to have the path to my cross-compiled libtool, I
get this error:

---(snip!)---
/tmp/gcc-4.0.2/builddir/gcc/xgcc -B/tmp/gcc-4.0.2/builddir/gcc/
-B/opt/darwin-cross/powerpc-apple-darwin8.0/bin/
-B/opt/darwin-cross/powerpc-apple-darwin8.0/lib/ -isystem
/opt/darwin-cross/powerpc-apple-darwin8.0/include -isystem
/opt/darwin-cross/powerpc-apple-darwin8.0/sys-include -O2  -DIN_GCC
-DCROSS_COMPILE   -W -Wall -Wwrite-strings -Wstrict-prototypes
-Wmissing-prototypes -Wold-style-definition  -isystem ./include 
-Wa,-force_cpusubtype_ALL -pipe -g -DHAVE_GTHR_DEFAULT -DIN_LIBGCC2
-D__GCC_FLOAT_NOT_NEEDED -Dinhibit_libc -dynamiclib -nodefaultlibs
-Wl,-install_name,/opt/darwin-cross/powerpc-apple-darwin8.0/lib/libgcc_s.1.0.dylib
-Wl,-flat_namespace -o ./libgcc_s.1.0.dylib.tmp
-Wl,-exported_symbols_list,libgcc/./libgcc.map -compatibility_version
1 -current_version 1.0  libgcc/./_muldi3_s.o libgcc/./_negdi2_s.o
libgcc/./_lshrdi3_s.o libgcc/./_ashldi3_s.o libgcc/./_ashrdi3_s.o
libgcc/./_cmpdi2_s.o libgcc/./_ucmpdi2_s.o libgcc/./_floatdidf_s.o
libgcc/./_floatdisf_s.o libgcc/./_fixunsdfsi_s.o
libgcc/./_fixunssfsi_s.o libgcc/./_fixunsdfdi_s.o
libgcc/./_fixdfdi_s.o libgcc/./_fixunssfdi_s.o libgcc/./_fixsfdi_s.o
libgcc/./_fixxfdi_s.o libgcc/./_fixunsxfdi_s.o libgcc/./_floatdixf_s.o
libgcc/./_fixunsxfsi_s.o libgcc/./_fixtfdi_s.o
libgcc/./_fixunstfdi_s.o libgcc/./_floatditf_s.o
libgcc/./_clear_cache_s.o libgcc/./_enable_execute_stack_s.o
libgcc/./_trampoline_s.o libgcc/./__main_s.o libgcc/./_absvsi2_s.o
libgcc/./_absvdi2_s.o libgcc/./_addvsi3_s.o libgcc/./_addvdi3_s.o
libgcc/./_subvsi3_s.o libgcc/./_subvdi3_s.o libgcc/./_mulvsi3_s.o
libgcc/./_mulvdi3_s.o libgcc/./_negvsi2_s.o libgcc/./_negvdi2_s.o
libgcc/./_ctors_s.o libgcc/./_ffssi2_s.o libgcc/./_ffsdi2_s.o
libgcc/./_clz_s.o libgcc/./_clzsi2_s.o libgcc/./_clzdi2_s.o
libgcc/./_ctzsi2_s.o libgcc/./_ctzdi2_s.o libgcc/./_popcount_tab_s.o
libgcc/./_popcountsi2_s.o libgcc/./_popcountdi2_s.o
libgcc/./_paritysi2_s.o libgcc/./_paritydi2_s.o libgcc/./_powisf2_s.o
libgcc/./_powidf2_s.o libgcc/./_powixf2_s.o libgcc/./_powitf2_s.o
libgcc/./_mulsc3_s.o libgcc/./_muldc3_s.o libgcc/./_mulxc3_s.o
libgcc/./_multc3_s.o libgcc/./_divsc3_s.o libgcc/./_divdc3_s.o
libgcc/./_divxc3_s.o libgcc/./_divtc3_s.o libgcc/./_divdi3_s.o
libgcc/./_moddi3_s.o libgcc/./_udivdi3_s.o libgcc/./_umoddi3_s.o
libgcc/./_udiv_w_sdiv_s.o libgcc/./_udivmoddi4_s.o
libgcc/./darwin-tramp_s.o libgcc/./darwin-ldouble_s.o
libgcc/./unwind-dw2_s.o libgcc/./unwind-dw2-fde-darwin_s.o
libgcc/./unwind-sjlj_s.o libgcc/./unwind-c_s.o
libgcc/./darwin-fallback_s.o -lc && rm -f ./libgcc_s.dylib && if [ -f
./libgcc_s.1.0.dylib ]; then mv -f ./libgcc_s.1.0.dylib
./libgcc_s.1.0.dylib.backup; else true; fi && mv
./libgcc_s.1.0.dylib.tmp ./libgcc_s.1.0.dylib && ln -s
libgcc_s.1.0.dylib ./libgcc_s.dylib
/opt/darwin-cross/bin/powerpc-apple-darwin8.0-libtool: file: -lc(/) is
not an object file (not allowed in a library)
/opt/darwin-cross/bin/powerpc-apple-darwin8.0-libtool: file: -lc(//)
is not an object file (not allowed in a library)
/opt/darwin-cross/bin/powerpc-apple-darwin8.0-libtool: file:
-lc(init-first.o/) is not an object file (not allowed in a library)
/opt/darwin-cross/bin/powerpc-apple-darwin8.0-libtool: file:
-lc(libc-start.o/) is not an object file (not allowed in a library)
/opt/darwin-cross/bin/powerpc-apple-darwin8.0-libtool: file:
-lc(sysdep.o/) is not an object file (not allowed in a library)
...
---(snip!)---

Do I need libc from a darwin system to link this?  Or should it be 
making a linux libgcc_s.so and it's somehow confused?