Welcome to the home of GNU Fortran

This web page is sadly out-of-date and difficult to maintain due to several factors. The rather small number of GNU Fortran developers have a large list of bugs to squash or features to implement, and the time spent maintaining this web page is better spent elsewhere. For up-to-date information, you may find the gfortran wiki a more useful site. The gfortran wiki can be changed by anyone who wishes to contribute. Neither copyright paperwork nor a patch review process is required.

The GNU Fortran project, or gfortran, is developing a Fortran compiler front end, as well as runtime libraries, for GCC, the GNU Compiler Collection. GNU Fortran development is a part of the GNU Project, aiming to bring free number crunching to all GNU system variants. The GNU Fortran development effort uses an open development environment in order to attract a larger team of developers and to ensure that gfortran can work on multiple architectures and diverse environments.

In particular, the project wishes to reach the users of the Fortran 95 language, be it in the scientific community, in education or in a commercial environment.

You can reach us at the fortran@gcc.gnu.org mailing list; for details please refer to our mailing lists page.

Project goal

We strive to provide a high quality release, which we want to work well on a variety of native targets. Although we believe we cannot make the best Fortran 95 compiler for any given target, we want GNU Fortran to be adequate.

The focus is on conformance to the Fortran 95 standard and on good performance of the executables produced by the compiler. Secondary goals include reasonable compile speed, a small memory foot print, the ability to build a cross-compiler, and Fortran 2003 features.

Extensions in GNU Fortran

The primary goal of the GNU Fortran Project is the construction of a Fortran 95 compiler that complies with the ISO Fortran 95 Programming Language standard [ISO/IEC 1539-1:1997(E)]. The gfortran wiki and the Bugzilla contain of features yet to be implemented for conformance.

Status of compiler and run time library

We regularly update the status of the front end development and of the run time library development. For a TODO list, check Bugzilla and the gfortran wiki.

Contributing

We encourage everyone to contribute changes and help test GNU Fortran. GNU Fortran is developed on the mainline of GCC and is part of the compiler collection since release 4.0.0 release of the compiler collection. We provide read access to our development sources for everybody with anonymous CVS. If you do not have CVS access (for instance because you are behind a firewall prohibiting the CVS protocol), you might want to download snapshots.

Contributions will be reviewed by the following people:

Paul Brook
Steven Bosscher
Toon Moene
Tobias Schlueter
Bud Davis
Janne Blomqvist
Steve Kargl
Thomas Koenig
Paul Thomas
Francois-Xavier Coudert

under the rules specified below:

Paul Brook and Steven Bosscher can unilaterally commit patches they deem reasonable, as they have set up the gfortran tree in GCC.
All normal requirements for patch submission (assignment of copyright to the FSF, testing, changelog entries, etc) still apply, and reviewers should ensure that these have been met before approving changes.
Approval should be necessary for patches which don't fall under the obvious rule, so with this list put in place everybody (except maintainers) should still seek approval for his/her patches.
Patches should only be reviewed by people who know the affected parts of the compiler. I.e. the reviewer has to be sure he/she knows stuff well enough to make a good judgement.
Large/complicated patches should still go by one of our maintainers.
We are all reasonable people, and nobody is working under employer pressure or needs an ego-boost badly, so in general we assume that noone deliberately does anything stupid :-)

The directories involved are:

gcc/gcc/fortran/
gcc/gcc/testsuite/gfortran.dg/
gcc/gcc/testsuite/gfortran.fortran-torture/
gcc/libgfortran/

Binaries

The GNU project is about providing source code for its programs. Sometimes, however, it is easier to install a binary directly. A number of people regularly build binaries for different platforms. Links to these can be found in the wiki.

Documentation

The manuals for release and current development versions of GNU Fortran can be downloaded from the GCC documentation page.

Usage

Here is a short explanation on how to invoke and use the compiler once you have built it (or downloaded the binary).