[Bug fortran/47495] .mod files: File modification time - Makefile build issue

[Joost.VandeVondele at pci dot uzh.ch]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47495

--- Comment #2 from Joost VandeVondele <Joost.VandeVondele at pci dot uzh.ch> 2011-01-27 16:52:07 UTC ---
Not sure if that solves the issue, but CP2K uses these rules:

%.o: %.F
        $(FC) -c $(FCFLAGS) $<


%.mod: %.o
        @true

with these style dependencies:

ai_coulomb_test.o ai_coulomb_test.mod : ai_coulomb_test.F cp_common_uses.h
cp_error_handling.mod cp_log_handling.mod physcon.mod ....

so faking that .mod is made up to date by having an up to date .o.