[Bug bootstrap/44959] [4.6 Regression] bootstrap failed at Comparing stages 2 and 3

[pinskia at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44959

--- Comment #31 from Andrew Pinski <pinskia at gcc dot gnu.org> 2012-09-01 
08:26:32 UTC ---
I don't think bootstrap-debug.mk cannot be used for alpha OSF.

configure checks to see if it is possible:
    if echo "int f (void) { return 0; }" > conftest.c &&
       ${CC} -c conftest.c &&
       mv conftest.o conftest.o.g0 &&
       ${CC} -c -g conftest.c &&
       mv conftest.o conftest.o.g &&
       ${srcdir}/contrib/compare-debug conftest.o.g0 conftest.o.g > /dev/null
2>&1; then
      :

But this uses the original compiler and not GCC to do the test.
You should be able to do --without-build-config .