No problem on Sun computer, but on PC with Windows XP the behavior is as you describe. E:\>gfortran -v Using built-in specs. Target: i686-pc-mingw32 Configured with: ../gcc/configure --prefix=/mingw --enable-languages=c,f95 Thread model: win32 gcc version 4.1.0 20050520 (experimental) The problem has existed since before 20 May.