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

[Daniel Mack]

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file man/custom-entities.ent was never rebuilt, and hence went out of
date and had to be deleted manually.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.


Daniel