https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91647
--- Comment #8 from Iain Sandoe <iains at gcc dot gnu.org> --- (In reply to Martin Sebor from comment #7) > Thanks, the trailing 10 in x86_64-apple-darwin10 makes the difference! hmm, something's odd then, 'x86_64-apple-darwin' works for me (I put a number out of habit more than necessity, in the host-only case***) $ ./gcc/xgcc -v Using built-in specs. COLLECT_GCC=./gcc/xgcc Target: x86_64-apple-darwin Configured with: ../src/configure --prefix=/home/iains/gcc-trunk/darwin --target=x86_64-apple-darwin *** having said that, I do recommend putting something between 10 and 18 there if you are building any libs, since some of them make dumb assumptions absent a darwin version. However, I don't expect you're building any libs - since that would require the SDK headers and Mach-O 'binutils' neither of which you (probably) have. ==== Thanks for the explanation - I wonder what happens for Linux when you use -fpic -mcmodel=medium?