SlackBuildsOrg/development/check

Check is a unit test framework for C. It features a simple interface
for defining unit tests, putting little in the way of the
developer. Tests are run in a separate address space, so Check can
catch both assertion failures and code errors that cause segmentation
faults or other signals. The output from unit tests can be used within
source code editors and IDEs.

See the project's home page for more information, including a tutorial.