Oddities in ./configure --with-pgtk's output

[Kévin Le Gouguec]

Hello folks,

I diff'ed the output of "./configure" and "./configure --with-pgtk" out
of curiosity; there are a couple of things that I found intriguing.
Some of them might warrant a bug report; since I could very well be
missing something, I thought I'd report here first.

(This is on openSUSE Tumbleweed, on commit 2021-12-19 "Add missing
implementation of `pgtk-menu-bar-open'" (579d7c20da))

> -checking for libwebp >= 0.6.0... yes

IIUC 'configure' guards WebP support behind several 'test "${HAVE_XXX}"'
clauses where XXX represents "something that supports displaying
images".  Should this be extended to ${HAVE_PGTK}?

> +checking for pkg-config... (cached) /usr/bin/pkg-config
> +checking pkg-config is at least version 0.16... yes

Not sure why this check is only present --with-pgtk?

> @@ -619,9 +592,9 @@
>    Does Emacs use -lxml2?                                  yes
>    Does Emacs use -lfreetype?                              yes
>    Does Emacs use HarfBuzz?                                yes
> -  Does Emacs use -lm17n-flt?                              yes
> +  Does Emacs use -lm17n-flt?                              
>    Does Emacs use -lotf?                                   yes
> -  Does Emacs use -lxft?                                   no
> +  Does Emacs use -lxft?                                   
>    Does Emacs use -lsystemd?                               yes
>    Does Emacs use -ljansson?                               yes
>    Does Emacs use the GMP library?                         yes

Should -lm17n-flt and -lxft say "no" instead of being empty?


At any rate, thanks for all the hard work.