[systemd-devel] [systemd-commits] Makefile.am

[Lennart Poettering]

On Fri, 29.05.15 12:26, Daniel Mack (daniel at zonque.org) wrote:

> On 05/29/2015 12:07 PM, Lennart Poettering wrote:
> > On Fri, 29.05.15 03:03, Daniel Mack (zonque at kemper.freedesktop.org) wrote:
> > 
> >>  Makefile.am |    2 +-
> >>  1 file changed, 1 insertion(+), 1 deletion(-)
> >>
> >> New commits:
> >> commit 6096d9ccc3f0b963010a47febce7e44c8632c23b
> >> Author: Daniel Mack <daniel at zonque.org>
> >> Date:   Fri May 29 12:00:58 2015 +0200
> >>
> >>     Makefile: make custom-entities.ent depend on Makefile.am
> >>     
> >>     When Makefile.am is modified, make sure custom-entities.ent is rebuilt.
> >>     After all, $(substitutions) is defined there, so changes of that variable
> >>     must be reflected in the resulting file.
> > 
> > Hmm, so we used have a lot of rules like this that mathematically
> > correctly rebuilt really everything touched by a change. However, this
> > resulted in soo much wasted build time, that we removed parts of it
> > again, even if this means that some man pages might be slightly out of
> > date if the Makefile.am changes.
> > 
> > hence: what is the impact of this change precisely? does this mean a
> > slight change of the makefile will always result in all man pages to
> > be rebuilt? we don#t do that for the C compilation logic when a
> > Makefile.am changes, so should we do this in this case?
> 
> This came up during the hackery around the custom entity logic. With
> changes to what $substitutions in Makefile.am contains, the resulting
> file man/custom-entities.ent was never rebuilt, and hence went out of
> date and had to be deleted manually.
> 
> But yes, that means the man pages will now be rebuilt every time
> Makefile.am is touched of course.

I'd prefer if we would avoid that. The xsltproc stuff already is the
slowest part of the build, and I wish touching the makefile would not
cause a full rebuild of that.

I think it's ok to expect people to run "make clean" after touching
the makefile to get the man pages fixed.

Hope that makes sense,

Lennart

-- 
Lennart Poettering, Red Hat