The automake 1.4 manual, and also the cvs version, says under
OMIT_DEPENDENCIES:
| When added to the @file{Makefile.in}, the dependencies have all
| system-specific dependencies automatically removed. This can be done by
| listing the files in @samp{OMIT_DEPENDENCIES}. For instance all
| references to system header files are removed by Automake. Sometimes it
| is useful to specify that a certain header file should be removed.
This is highly confusing, and should be rephrased, and I'm not sure
I understand it correctly.
Attempt at interpretation: references to system header files are
removed anyway, and, to additionally ignore certain (distribution)
files, they are listed in OMIT_DEPENDENCIES.
