The flags passed to runtest by default are held in the variable RUNTESTDEFAULTFLAGS. Its default value is --tool $$tool --srcdir $$srcdir. $$tool will expand to each tool specified in DEJATOOL and $$srcdir to the full name of the source directory.

This variable can be overridden in the configuration file.

It is also sometimes useful to override runtest options just within the Makefile.am. This can be done by setting the variable AM_RUNTESTFLAGS within the Makefile.am.