On 16 January 2012 13:55, Hans Aberg wrote: > [I am not on this list, so please cc me.] > > On OS X 10.7.2, gcc (GCC) 4.7.0 20120115 from SVN compiles using the > /usr/bin/gcc -> llvm-gcc-4.2 that is installed by Xcode 4.2.1. > > But if one first compiles GCC 4.6.2 using the same LLVM-GCC, then this GCC > 4.7 will not compile; there is a configure error: > > checking for long long... yes > checking size of long long... configure: error: in > `/usr/local/src/gcc/gcc/host-x86_64-apple-darwin11.2.0/gcc': > configure: error: cannot compute sizeof (long long) > See `config.log' for more details. > > The config.log of this directory just indicates a program doing the check > that will fail (now overwritten by new ./configure && make).
Do not run ./configure, see http://gcc.gnu.org/wiki/InstallingGCC and http://gcc.gnu.org/wiki/FAQ#configure and http://gcc.gnu.org/install/configure.html - you have to try pretty hard to avoid that tip if you read any installation docs at all. The check in the config.log is what's needed to identify the problem. The problem might go away if you stop using ./configure, if not then try asking on the gcc-help list, or submitting it to bugzilla if you think it's a gcc bug.
