Development-time tools

Change management


GROMACS uses git as the version control system. Instructions for setting up git for GROMACS, as well as tips and tricks for its use, can be found on the wiki: Git Tips & Tricks

Other basic tutorial material for git can be found on the web.

All code changes go through a code review system at
All changes pushed to Gerrit are automatically compiled and otherwise checked on various platforms using a continuous integration system at Understanding Jenkins builds documents how Jenkins interacts with the build system, providing information on how to replicate the builds Jenkins does (e.g., to diagnose issues).
Bugs and issues, as well as some random features and discussions, are tracked at

Build system

Main tool used in the build system.

packaging for distribution (CPack)

unit testing (CTest)
GROMACS uses a unit testing framework based on Google C++ Testing Framework (gtest) and CTest. All unit tests are automatically run on Jenkins for each commit. Details can be found on a separate page on Unit testing.

regression tests

cppcheck is used for static code analysis, and is run automatically on Jenkins for each commit. Different rules are used for C and C++ code (with stricter checking for C++ code, as that is newer). The build system provides a cppcheck target (produced from tests/CppCheck.cmake) to run the tool. This target is used also by Jenkins.

clang static analyzer

Code formatting and style

The tools and scripts listed below are used to automatically check/apply formatting that follows GROMACS style guidelines described on a separate page: Style guidelines.

uncrustify is used for automatic indentation and other formatting of the source code to follow Guidelines for code formatting. All code must remain invariant under uncrustify with the config at admin/uncrustify.cfg. A patched version of uncrustify is used. See Automatic source code formatting for details.
This Python script adds and formats copyright headers in source files. (see below) uses the script to check/update copyright years on changed files automatically.
This bash script runs uncrustify and for all files that have local changes and checks that they conform to the prescribed style. Optionally, the script can also apply changes to make the files conform. This script is automatically run by Jenkins to ensure that all commits adhere to Guidelines for code formatting. If the uncrustify job does not succeed, it means that this script has something to complain. See Automatic source code formatting for details.
This sample git pre-commit hook can be used if one wants to apply automatically before every commit to check for formatting issues. See Automatic source code formatting for details.
This Python script sorts and reformats #include directives according to the guidelines at Guidelines for #include directives. Details are documented on a separate page (with the whole suite of Python scripts used for source code checks): Include order sorting.
include directive checker
In its present form, the above include sorter script cannot be conveniently applied in To check for issues, it is instead integrated into a check-source build target. When this target is built, it also checks for include formatting issues. Internally, it uses the sorter script. This check is run in Jenkins as part of the Documentation job. Details for the checking mechanism are on a separate page (common for several checkers): Source tree checker scripts.
This bash script runs uncrustify/ sorter on all relevant files in the source tree (or in a particular directory). The script can also produce the list of files where these scripts are applied, for use with other scripts. See Automatic source code formatting for details.
git attributes
git attributes (specified in .gitattributes files) are used to annotate which files are subject to automatic formatting checks (and for automatic reformatting by the above scripts). See man gitattributes for an overview of the mechanism. We use the filter attribute to specify the type of automatic checking/formatting to apply. Custom attributes are used for specifying some build system dependencies for easier processing in CMake.


Documentation generation

Building the GROMACS documentation

For now, there are multiple components, formats and tools for the GROMACS documentation, which is aimed primarily at version-specific deployment of the complete documentation on the website.

This is quite complex, because the dependencies for building the documentation must not get in the way of building the code (particularly when cross-compiling), and yet the code must build and run in order for some documentation to be generated. Also, man page documentation (and command-line completions) must be built from the wrapper binary, in order to be bundled into the tarball.

The outputs of interest to most developers are generally produced in the docs/html/ subdirectory of the build tree.

You need to enable at least some of the following CMake options:

Option needed for trying to build the PDF reference manual (requires LaTeX and ImageMagick)
Option that controls 1) whether shell completions are built automatically, and 2) whether built man pages are installed if available (the user still needs to build the man target manually before installing)

Some documentation cannot be built if the CMake option GMX_BUILD_MDRUN_ONLY is enabled, or when cross-compiling, as it requires executing the gmx binary.

The following make targets are the most useful:

Builds the PDF reference manual
Makes man pages from the wrapper binary with Sphinx
Makes the code documentation with Doxygen
Makes the INSTALL file for the tarball with Sphinx
Makes all the components of the GROMACS webpage that require Sphinx, including install guide and user guide.

Makes the complete GROMACS webpage, requires everything. When complete, you can browse docs/html/index.html to find everything.

If built from a release tarball, the SOURCE_MD5SUM, SOURCE_TARBALL, REGRESSIONTESTS_MD5SUM, and REGRESSIONTESTS_TARBALL CMake variables can be set to pass in the md5sum values and names of those tarballs, for embedding into the final deployment to the GROMACS website.

The following tools are used in building parts of the documentation.

Doxygen is used to extract documentation from source code comments. Also some other overview content is laid out by Doxygen from Markdown source files. Currently, version 1.8.5 is required for a warning-free build. Thorough explanation of the Doxygen setup and instructions for documenting the source code can be found on a separate page: Using Doxygen.
graphviz (dot)
The Doxygen documentation uses dot from graphviz for building some graphs. The tool is not mandatory, but the Doxygen build will produce warnings if it is not available, and the graphs are omitted from the documentation.
The Doxygen documentation uses mscgen for building some graphs. As with dot, the tool is not mandatory, but not having it available will result in warnings and missing graphs.
Doxygen issue checker
Doxygen produces warnings about some incorrect uses and wrong documentation, but there are many common mistakes that it does not detect. GROMACS uses an additional, custom Python script to check for such issues. This is most easily invoked through a check-source target in the build system. The script also checks that documentation for a header matches its use in the source code (e.g., that a header documented as internal to a module is not actually used from outside the module). These checks are run in Jenkins as part of the Documentation job. Details for the custom checker are on a separate page (common for several checkers): Source tree checker scripts.
module dependency graphs
GROMACS uses a custom Python script to generate an annotated dependency graph for the code, showing #include dependencies between modules. The generated graph is embedded into the Doxygen documentation: Module dependency graph This script shares most of its implementation with the custom checkers, and is documented on the same page: Source tree checker scripts.
Sphinx; at least version 1.2.3) is used for building some parts of the documentation from reStructuredText source files.
Also requires ImageMagick for converting graphics file formats.


documentation exported from source files
For man pages, HTML documentation of command-line options for executables, and for shell completions, the gmx binary has explicit C++ code to export the information required. The build system provides targets that then invoke the built gmx binary to produce these documentation items. The generated items are packaged into source tarballs so that this is not necessary when building from a source distribution (since in general, it will not work in cross-compilation scenarios). To build and install these from a git distribution, explicit action is required. See Doxygen documentation on the wrapper binary for some additional details.