cannot install gfortran-lion-5666-3.pkg

As a test I downloaded and tried to install gfortran-lion-5666-3.pkg. It does not like the fact that Xcode 4.1 comes with gcc build 5658, rather than 5666.3, and it does not install.

Lion, Xcode 4.1

gcc --version
i686-apple-darwin11-llvm-gcc-4.2 (GCC) 4.2.1 (Based on Apple Inc. build 5658) (LLVM build 2335.15.00)
Copyright (C) 2007 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

Wrong reason. The only reason it won't install on Lion is if you don't have gcc-42 in the system location. The high-level check is that this must work:

ginaz:Lion$ /usr/bin/gcc-4.2 --version
i686-apple-darwin11-gcc-4.2.1 (GCC) 4.2.1 (Apple Inc. build 5666) (dot 3)
Copyright (C) 2007 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.


The actual test is that /usr/libexec/gcc/i686-apple-darwin11/4.2.1/cc1 must be present:

ginaz:Lion$ ls -l /usr/libexec/gcc/i686-apple-darwin11/4.2.1/cc1
-rwxr-xr-x@ 1 root  wheel  12486976 Jul 22 18:55 /usr/libexec/gcc/i686-apple-darwin11/4.2.1/cc1

The reason is that the package will update it so if you don't have it, you don't have Xcode in the right place so it won't work.

Cheers,
Simon