http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57792
--- Comment #7 from Jack Howarth <howarth at nitro dot med.uc.edu> --- (In reply to Jack Howarth from comment #6) My mistake in mixing host_configargs and build_configargs. The following patch works fineā¦ Index: configure.ac =================================================================== --- configure.ac (revision 200683) +++ configure.ac (working copy) @@ -2848,6 +2848,13 @@ if test x${is_cross_compiler} = xyes ; t target_configargs="--with-cross-host=${host_noncanonical} ${target_configargs}" fi +# Pass --with-sysroot on darwin without SDK in / +case "${target}" in + x86_64-*-darwin1[[3-9]]*) + host_configargs="--with-sysroot=\"`xcrun --show-sdk-path`\" ${host_configargs}" + ;; +esac + # Default to --enable-multilib. if test x${enable_multilib} = x ; then target_configargs="--enable-multilib ${target_configargs}"