[Cook] strange behaviour

[Aryeh M. Friedman]

If I am using the full project build as Peter recommends in the manual
(only tiny variant in that it loops on lib/lib%.a_obj vs. just making
it for one lib) why does it take a couple of cooks for it to think
that all the targets are upto date.  Example:

cook 1:

compiles all the sources
makes the libs
installs the executables

cook 2:
makes the last lib
installs the executables

cook 3:
installs the executables

cook 4:
no action

	--Aryeh
BTW if this is a bug I am using 2.21 on FreeBSD 4.6