https://gcc.gnu.org/bugzilla/show_bug.cgi?id=54052
--- Comment #7 from Jonathan Wakely <redi at gcc dot gnu.org> --- (In reply to Eric Gallager from comment #6) > Doesn't ICE for me, just takes an inordinately long time to compile (once I > add -fpermissive): You should have used -m32 not -fpermissive, the preprocessed source was created on i686-pc-cygwin i.e. an ILP32 target. That's why you got those warnings on x86_64. > Extra diagnostic checks enabled; compiler may run slowly. > Configure with --enable-checking=release to disable checks. It's expected that compilation takes longer when those checks are enabled. The code has an unreasonably large expression, so it's not entirely surprising that it takes unreasonable long to optimize.