Re: how to allow multiple empty commands?

[Eric Melski]

Mark Galeck (CW) wrote:

> So I thought, the best way to tell make, to not look for implicit
> rules for header files, is to have lines like
>
> foobar.h:;
>
> in all my automatically generated dependency makefiles.  The problem
> is, thousands of those makefiles are always included, and they have
> all those duplicate lines, each header file, is present in many of
> them.
>
>
> ...  But I can't due to
> make complaining.  Well I can, it's just that I have to dump the
> warnings into a devnull. Somehow this doesn't seem right :)


Rather than emitting simply:

        foobar.h:;

Why not emit something like this:

        ifndef _foobar_rule
        foobar.h:;
        _foobar_rule=1
        endif

This way you get only one definition of the rule, the first time it is 
encountered.  Of course this will add an extra variable to your variable 
table, one per header file, which may or may not be a problem itself.

HTH,

Eric Melski
Electric Cloud, Inc.
http://blog.electric-cloud.com