pkg-config required on OSX, why?

pkg-config required on OSX, why?

[Jan D.]

Hello.

Why is pkg-config a requirement on OSX?
Emacs builds fine without it.  In fact it is not called anywhere and is 
not needed.

If it is a requirement, can someone please put some notes in admin where 
to get pkg-config for OSX.  I don't think installing Homebrew or 
MacPorts just to build Emacs is reasonable.

Thanks,

	Jan D.

Re: pkg-config required on OSX, why?

[Eli Zaretskii]

> Date: Fri, 16 May 2014 13:01:23 +0200
> From: "Jan D." <jan.h.d@swipnet.se>
> 
> Why is pkg-config a requirement on OSX?

Are you sure it is needed for building Emacs, and not just for running
autogen.sh/aclocal in order to produce the configure script when
building out of the repository?

The latter is indeed new, and is because configure.ac now calls a
macro that is defined by pkg.m4, which comes with pkg-config.

Re: pkg-config required on OSX, why?

[Jan D.]

Hi.

Eli Zaretskii skrev 2014-05-16 15:07:
>> Date: Fri, 16 May 2014 13:01:23 +0200
>> From: "Jan D." <jan.h.d@swipnet.se>
>>
>> Why is pkg-config a requirement on OSX?
>
> Are you sure it is needed for building Emacs, and not just for running
> autogen.sh/aclocal in order to produce the configure script when
> building out of the repository?

It is requred for that also, but pkg-config is run in configure also.

>
> The latter is indeed new, and is because configure.ac now calls a
> macro that is defined by pkg.m4, which comes with pkg-config.
>

Yes, I saw those undefined macros (I think it was three) when trying to 
build without pkg-config after tweaking autogen.sh.

I built pkg-config from source, but having pkg-config as a requirement 
form some macros must mean those macros are important.  What are they?

	Jan D.

Re: pkg-config required on OSX, why?

[Paul Eggert]

Jan D. wrote:
> having pkg-config as a requirement form some macros must mean those
> macros are important.  What are they?

Among other things, the macros test whether pkg-config is present, and 
they do the right thing when pkg-config is absent.  One needs the macros 
only to run 'autoconf' etc., not to run 'configure'.

It does strike me, though, that this new requirement to have pkg-config 
installed (and in the same place that automake is installed) is a pain. 
  I ran afoul of it myself not five minutes ago, since I use my own 
automake.  I'm inclined to have us copy pkg.m4 into m4, using a new tool 
(admin/merge-pkg-config, say).  That way, someone can periodically 
upgrade to the latest pkg.m4 manually, and the rest of us won't have to 
worry about having pkg-config installed correctly.

Re: pkg-config required on OSX, why?

[Stefan Monnier]

> It does strike me, though, that this new requirement to have pkg-config
> installed (and in the same place that automake is installed)
> is a pain. I ran afoul of it myself not five minutes ago, since I use my own
> automake.  I'm inclined to have us copy pkg.m4 into m4, using a new tool
> (admin/merge-pkg-config, say).  That way, someone can periodically upgrade
> to the latest pkg.m4 manually, and the rest of us won't have to worry about
> having pkg-config installed correctly.

Please do that.  Building from Bazaar (or Git) is an important use case.


        Stefan "who sees the case of building from a tarball as the exception
                rather than the rule"

Re: pkg-config required on OSX, why?

[Paul Eggert]

Paul Eggert wrote:
> I'm inclined to have us copy pkg.m4 into m4

I installed something along those lines, as trunk bzr 117116, so you 
shouldn't need pkg-config on OS X any more.

Re: pkg-config required on OSX, why?

[Glenn Morris]

Paul Eggert wrote:

> I installed something along those lines, as trunk bzr 117116, so you
> shouldn't need pkg-config on OS X any more.

This breaks the build:

http://hydra.nixos.org/build/10995488

    checking for ALSA... no
    configure: error: pkg-config found alsa, but it does not compile.  See
    config.log for error messages.
    make: *** [Makefile] Error 1

Re: pkg-config required on OSX, why?

[Jan D.]

Hello.

Paul Eggert skrev 2014-05-16 17:52:
> Paul Eggert wrote:
>> I'm inclined to have us copy pkg.m4 into m4
>
> I installed something along those lines, as trunk bzr 117116, so you
> shouldn't need pkg-config on OS X any more.

Thanks for your effort, but something is not right.
Configure detects that no ALSA is present, but still goes ahead and 
tries to compile an ALSA program:

checking for ALSA... no
configure: error: pkg-config found alsa, but it does not compile.  See 
config.log for error messages.

A sh -x on configure gives:

+ ALSA_REQUIRED=1.0.0
+ ALSA_MODULES='alsa >= 1.0.0'
+ pkg_failed=no
+ printf '%s\n' 'configure:9554: checking for ALSA'
+ printf %s 'checking for ALSA... '
+ test -n ''
+ test -n ''
+ pkg_failed=untried
+ test -n ''
+ test -n ''
+ pkg_failed=untried
+ test untried = yes
+ test untried = untried
+ printf '%s\n' 'configure:9613: result: no'
+ printf '%s\n' no
+ :
+ HAVE_ALSA=yes

So HAVE_ALSA becomes yes, even if it printed no on the line before.
Let me know if you need any more debugging help.

	Jan D.

Re: pkg-config required on OSX, why?

[Paul Eggert]

On 05/16/2014 09:50 AM, Jan D. wrote:
> Thanks for your effort, but something is not right. 

Argh, it worked for me.  But there was a typo in EMACS_CHECK_MODULES 
that caused it to not work sometimes when pkg-config failed.  I 
installed a patch as trunk bzr 117117.  Hope this fixes the hydra build too.

Re: pkg-config required on OSX, why?

[Jan Djärv]

Hi.

16 maj 2014 kl. 21:04 skrev Paul Eggert <eggert@cs.ucla.edu>:

> On 05/16/2014 09:50 AM, Jan D. wrote:
>> Thanks for your effort, but something is not right. 
> 
> Argh, it worked for me.  But there was a typo in EMACS_CHECK_MODULES that caused it to not work sometimes when pkg-config failed.  I installed a patch as trunk bzr 117117.  Hope this fixes the hydra build too.

Works fine now, thanks.

	Jan D.

Re: pkg-config required on OSX, why?

[Glenn Morris]

"Jan D." wrote:

> I built pkg-config from source, but having pkg-config as a requirement
> form some macros must mean those macros are important.  What are they?

The ones that test for any halfway-modern library.
Eg svg, imagemagick, etc, etc. Basically anywhere you see EMACS_CHECK_MODULES.

Installing pkg-config is a one-time cost. It took me ~ 2 mins.
You'll "never" have to update it.
Even the MS Windows users seemed to manage, eventually. ;)
So I hope you give it a go...

Re: pkg-config required on OSX, why?

[Jan D.]

Hello.

Glenn Morris skrev 2014-05-16 17:57:
> "Jan D." wrote:
>
>> I built pkg-config from source, but having pkg-config as a requirement
>> form some macros must mean those macros are important.  What are they?
>
> The ones that test for any halfway-modern library.
> Eg svg, imagemagick, etc, etc. Basically anywhere you see EMACS_CHECK_MODULES.

On the other hand, configure has called pkg-config ever since Gtk+ 
entered the Emacs source.

>
> Installing pkg-config is a one-time cost. It took me ~ 2 mins.
> You'll "never" have to update it.
> Even the MS Windows users seemed to manage, eventually. ;)
> So I hope you give it a go...
>

I have, but things have now moved on.

	Jan D.

Re: pkg-config required on OSX, why?

[Glenn Morris]

"Jan D." wrote:

> On the other hand, configure has called pkg-config ever since Gtk+
> entered the Emacs source.

Yes, so I imagine almost everyone already had pkg-config installed.
It is required to use many of the libraries that we have decided are
(quasi-)essential for a "fully" functioning Emacs.
Not sure what your point is here.

> I have, but things have now moved on.

No point discussing it then.

Re: pkg-config required on OSX, why?

[Jan D.]

Hi.

Glenn Morris skrev 2014-05-16 18:46:
> "Jan D." wrote:
>
>> On the other hand, configure has called pkg-config ever since Gtk+
>> entered the Emacs source.
>
> Yes, so I imagine almost everyone already had pkg-config installed.
> It is required to use many of the libraries that we have decided are
> (quasi-)essential for a "fully" functioning Emacs.
> Not sure what your point is here.
>

Something like: it was never required for NS before, and the old usage 
of pkg-config managed without those macros that now are essential.

>> I have, but things have now moved on.
>
> No point discussing it then.
>

Not really, no.

	Jan D.