3.3.5.1 About gnatkr

GNAT requires that the file name must be derived from the unit name. The default rule is as follows:

The -gnatk`nn' switch of the compiler activates a ‘krunching’ circuit that limits file names to nn characters (where nn is a decimal integer).

You can use the gnatkr utility to determine the krunched name for a given file when krunched to a specified maximum length.