http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52946
--- Comment #3 from Lund <lunfis at gmx dot de> 2012-04-13 01:08:12 UTC --- OK, my mistake. I did not realize Apple's gcc was that different. In case, anyone else comes across this issue, I was able to work around it by installing clang/LLVM and get the 'blocks' library from here: https://github.com/mackyle/blocksruntime.