14.4 Checking the Distribution

Automake also generates a distcheck rule that can be of help to ensure that a given distribution will actually work. distcheck makes a distribution, then tries to do a VPATH build (see section Parallel Build Trees (a.k.a. VPATH Builds)), run the test suite, and finally make another tarball to ensure the distribution is self-contained.

Building the package involves running ‘./configure’. If you need to supply additional flags to configure, define them in the DISTCHECK_CONFIGURE_FLAGS variable, either in your top-level ‘Makefile.am’, or on the command line when invoking make.

If the distcheck-hook rule is defined in your top-level ‘Makefile.am’, then it will be invoked by distcheck after the new distribution has been unpacked, but before the unpacked copy is configured and built. Your distcheck-hook can do almost anything, though as always caution is advised. Generally this hook is used to check for potential distribution errors not caught by the standard mechanism. Note that distcheck-hook as well as DISTCHECK_CONFIGURE_FLAGS are not honored in a subpackage ‘Makefile.am’, but the DISTCHECK_CONFIGURE_FLAGS are passed down to the configure script of the subpackage.

Speaking of potential distribution errors, distcheck also ensures that the distclean rule actually removes all built files. This is done by running ‘make distcleancheck’ at the end of the VPATH build. By default, distcleancheck will run distclean and then make sure the build tree has been emptied by running ‘$(distcleancheck_listfiles)’. Usually this check will find generated files that you forgot to add to the DISTCLEANFILES variable (see section What Gets Cleaned).

The distcleancheck behavior should be OK for most packages, otherwise you have the possibility to override the definition of either the distcleancheck rule, or the ‘$(distcleancheck_listfiles)’ variable. For instance, to disable distcleancheck completely, add the following rule to your top-level ‘Makefile.am’:

distcleancheck:
        @:

If you want distcleancheck to ignore built files that have not been cleaned because they are also part of the distribution, add the following definition instead:

distcleancheck_listfiles = \
  find . -type f -exec sh -c 'test -f $(srcdir)/$$1 || echo $$1' \
       sh '{}' ';'

The above definition is not the default because it's usually an error if your Makefiles cause some distributed files to be rebuilt when the user build the package. (Think about the user missing the tool required to build the file; or if the required tool is built by your package, consider the cross-compilation case where it can't be run.) There is an entry in the FAQ about this (see section Files left in build directory after distclean), make sure you read it before playing with distcleancheck_listfiles.

distcheck also checks that the uninstall rule works properly, both for ordinary and DESTDIR builds. It does this by invoking ‘make uninstall’, and then it checks the install tree to see if any files are left over. This check will make sure that you correctly coded your uninstall-related rules.

By default, the checking is done by the distuninstallcheck rule, and the list of files in the install tree is generated by ‘$(distuninstallcheck_listfiles)’ (this is a variable whose value is a shell command to run that prints the list of files to stdout).

Either of these can be overridden to modify the behavior of distcheck. For instance, to disable this check completely, you would write:

distuninstallcheck:
        @: