bug#53900: 29.0.50; pgtk: Gtk-CRITICAL warning with customized default face

[Stephen Berman]

On Thu, 10 Feb 2022 10:12:08 +0800 Po Lu <luangruo@yahoo.com> wrote:

> Stephen Berman <stephen.berman@gmx.net> writes:
>
>> 0. emacs -Q
>> 1. Sanity check: evaluating the following sexp displays a non-GTK
>>    tooltip and the shell emits no warning:
>>    (let (use-system-tooltips)
>>     (tooltip-show "Test"))
>> 2. Evaluate this sexp:
>>    (custom-set-faces '(default ((t (:background "lightblue")))))
>> 3. Evaluate the sexp in step 1 again:
>> => A non-GTK tooltip is displayed and the shell emit a warning:
>>
>> emacs-pgtk:12321): Gtk-CRITICAL **: 17:05:36.422: 
>> gtk_css_provider_load_from_data: assertion 'GTK_IS_CSS_PROVIDER 
>> (css_provider)' failed
>>
>> In my tests this happens only when customizing the `default' face
>> (though admittedly I haven't tested all faces nor all face attributes).
>> It also happens when step 2 is replaced by loading any built-in theme
>> (all of which customize the `default' face).  (As a test I created a
>> theme that does not customize the `default' face and with that theme did
>> not get the warning.)
>>
>> My first pgtk-build that shows this warning is from commit
>> dc5930ba973c9d921e9124b7afa1a65bba568b45.  My previous pgtk-build at
>> commit 988d3d79bac0343dd2b1b89d1b15470edbb5e6ac does not show the
>> warning with the above recipe.  Unfortunately, I don't have time now to
>> do a git bisect to pinpoint the commit that causes the warning to be
>> emitted.
>>
>> There is no warning if use-system-tooltips is non-nil.  And there is no
>> warning with the above recipe in a non-PGTK GTK3 build.
>
> Should be fixed now on master.  Thanks.

Confirmed, so I'm closing the bug.  Thanks.

Steve Berman