Thanks to Steve Ellcey for having asked the question I did not care (dare) to ask and to those who answered.
> So please use contrib/test_installed This script seems quite outdated: it tests g77 and not gfortran, even with the latest 4.3.0 snapshot (20070112). As I was primarily interested in the gfortran tests, I replaced g77 by gfortran everywhere (keeping the different capitalizations) and it worked. The script also ignores java tests. I looked again to the manual (http://gcc.gnu.org/install/test.html) and did not find this script documented anywhere. Am I missing something or is this a place where the manual can be improved? Note that I am installing gcc on Mac OSX/PPC through a fink script that does not keep the building directory, so my choices are either to make further changes to the script to include the appropriate "make check" (this will increase both the building time by several hours and the risk of failure after several hours) or to do a postinstall check (my choice, unless someone offers a better solution). Cheers Dominique