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Re: @true in makefiles
> The cases you have to look at are the ones with move-if-change. You
> have to make sure that if the file does not change, none of the
> dependencies are considered to have changed.
>
> For example in
>
> multilib.h: s-mlib; @true
> s-mlib: $(srcdir)/genmultilib Makefile
> ...
> $(SHELL) $(srcdir)/../move-if-change tmp-mlib.h multilib.h
> $(STAMP) s-mlib
>
> we need the property that if multilib.h changes, everything that
> depends upon it gets rebuilt. If genmultilib or Makefile changes, we
> must try rebuilding multilib.h. However, if multilib.h does not then
> change, then things that depend upon multilib.h should not get rebuilt
> for that reason.
>
> The @true is necessary so that make checks whether the timestamp of
> multilib.h changed before deciding that it will rebuild things that
> depend upon multilib.h.
>
> Can you restate your plan based on that, showing examples which use
> move-if-change? Thanks.
Unfortunately no :(
but I think that I can document that :)
I will make a small example and add a comment to Makefile.in
describing the use of stamps with mkconfig.sh and move-if-change.
One small improvement would be to create the dependencies on s-gtype
automatically. At least the Make-lang.in s wouldn't need to know about
the stamps. Maybe I can implement this.
> Ian
Thank you very much,
Rafael