The configure script will choose a Fortran 95 compiler before it settles for a Fortran 77 one. Some of the code requires a Fortran 77 compiler (at least at present, possibly indefinitely), and so if you have more than one Fortran compiler installed, you'll have to force the build system with a command like:
where the Tru64 Fortran 77 compiler is called% ./configure FC=f77 [other arguments]
f77. You
can give the path to the compiler also, if the f77 you want isn't the
first one in your PATH. Since this sort of robustness is
the sort of thing we'll continue to work on, don't do this until you
have empirically determined that it won't work otherwise.The Tru64 C and C++ compilers should work fine: if you have more
than one compiler installed, you can force them with the configure
arguments CC=cc and CXX=cxx; but this
shouldn't be necessary.