http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49992
--- Comment #7 from Dominique d'Humieres <dominiq at lps dot ens.fr> 2011-08-08 18:12:34 UTC --- > Apparently the key is "--enable-checking=something". It is even more subtle (x86_64-apple-darwin10): ../work/configure --prefix=/opt/gcc/gcc4.7w --enable-languages=c,c++,fortran,objc,obj-c++,java --with-gmp=/opt/sw64 --with-libiconv-prefix=/opt/sw64 --with-system-zlib --with-cloog=/opt/sw64 --enable-cloog-backend=isl --enable-checking=none fails, while ../work/configure --prefix=/opt/gcc/gcc4.7w --enable-languages=c,c++,fortran,objc,obj-c++,java --with-gmp=/opt/sw64 --with-libiconv-prefix=/opt/sw64 --with-system-zlib --with-cloog=/opt/sw64 --enable-cloog-backend=isl --enable-checking=yes succeeds. This for bootstraps wthout lto enabled: [macbook] f90/bug% gfc pr49638_2.f90 -flto f951: error: LTO support has not been enabled in this configuration
