Bug#984364: Bug#984162 etc.: gtksourceview4 etc.: ftbfs with GCC-11

[Simon McVittie]

Control: block -1 by 984437

On Wed, 03 Mar 2021 at 16:12:57 +0000, Matthias Klose wrote:
> ../gtksourceview/gtksourcecompletion.c: In function ‘gtk_source_completion_get_type’:
> /usr/include/glib-2.0/glib/gatomic.h:112:5: error: argument 2 of ‘__atomic_load’ discards ‘volatile’ qualifier [-Werror=incompatible-pointer-types]
(etc.)

These all look like they result from the same GLib bug, which is believed
to be fixed in experimental already.

    smcv