Re: [PATCH] sed: remove obsolete advice from --help output

[Jim Meyering]

On Sun, Aug 14, 2016 at 6:05 PM, Assaf Gordon <address@hidden> wrote:
> Hello Jim,

Hi Assaf,

Thanks for the quick feedback.

>> On Aug 14, 2016, at 20:05, Jim Meyering <address@hidden> wrote:
>>
>> On Sun, Aug 14, 2016 at 4:32 PM, Jim Meyering <address@hidden> wrote:
>>> While preparing the attached patch, I discovered a missing dependency bug.
>>> To demonstrate, run "touch sed/sed.c; rm -f sed/sed; make", and witness 
>>> this:
>>>
>> [...]
>> Here's the patch for the above along with a few other build-related issues:
>> <sed-build-deps-and-distcheck.diff>
>
> Regarding the man page regeneration:
>
> I think this is the same issue I encountered with "make -j".

Probably. The problem I was fixing arose only with make -j.

> I suspect the "ideal" solution would've been to use gnu make's 
> "order-only-prerequisites",
> so that the man page needs to be rebuilt only of sed.c was modified, but wait 
> until 'sed' binary is built:
>    doc/sed.1: $(srcdir)/src/sed.c .version $(srcdir)/doc/sed.x | sed/sed
> However, this will require 'gnu make' to build sed, so I guess is 
> unacceptable.
>
> If we require 'help2man' to build sed, it makes 'perl' a requirement (instead 
> of just shell/make/compiler).
> In coreutils there's the "dummy-man" script for cases 'perl' is missing.
>
> An alternative which I've used in other projects is to build the man page 
> only if the project is built from 'git'.
> It is them packed inside the tarball, and installed as-is (assuming that most 
> users who build from tarball have not changed sed.c at all, and there's no 
> need to rebuild the man page).
>
> Perhaps this is a bit overthinking, and just requiring perl is fine.

I think it would be fine to make perl a requirement for generating
documentation.

> Regarding changes in the 'doc/sed.texi' target:
> (I must confess I'm writing only based on reading the patch, I'll be able to 
> try/test/verify tomorrow evening.)
>
> The file 'doc/sed.texi' perhaps needs more changes: It is both auto-generated 
> from 'doc/sed-in.texi' AND checked into the git repository.
> When I converted to non-recursive makefiles, I kept it as 
> '$(top_srcdir)/doc/sed.texi' to keep as much as possible as the old makefile 
> system. If we change it now to 'doc/sed.texi' (which will of course work 
> better in out-of-tree builds),
> perhaps we should consider removing it completely from the git repository and 
> always rebuild it?

I too would like to stop version-controlling that file, but am happy
to defer that project to another day. You're welcome to work on it, of
course. My primary goal with these changes was to make "make
distcheck" work for me once again.