bug#74383: 29.4; Emacs PGTK crashes on Void Linux

[Po Lu]

Eli Zaretskii <eliz@gnu.org> writes:

>> From: Taha Aziz Ben Ali <ba.tahaaziz@gmail.com>
>> Date: Sat, 16 Nov 2024 13:42:39 +0100
>> 
>> I've been failing to get Emacs to launch under Sway on Void Linux, the
>> configuration I'm using was working fine on Arch Linux (using the same
>> Emacs version). Note that `emacs -Q' also segfaults, but `emacs -nw' is
>> able to launch emacs with all of my configuration without a single
>> warning.
>> 
>> You can find the backtrace leading up to this error in this paste:
>> 
>>   https://paste.sr.ht/~grtcdr/c39dad4913262557228d1158680f52613b728c6a
>> 
>> I tracked the issue down to a cairo_surface_create_similar_image() call
>> that results in the crash.
>> 
>> Before the program crashes, a warning about the "xpm" image type not
>> being supported is shown which may be relevant:
>> 
>>   (emacs:8670): GdkPixbuf-WARNING **: 13:38:44.606: Error loading XPM
>>   image loader: Image type “xpm” is not supported
>
> Do you have the XPM library installed and available to Emacs?
>
> Your build details indicate that Emacs was configured to be built with
> XPM:
>
>> Configured using:
>>  'configure --with-pgtk --prefix=/usr --sysconfdir=/etc
>>  --sbindir=/usr/bin --bindir=/usr/bin --mandir=/usr/share/man
>>  --infodir=/usr/share/info --localstatedir=/var
>>  --host=x86_64-unknown-linux-musl --build=x86_64-unknown-linux-musl
>>  '--libdir=${exec_prefix}/lib64' --with-file-notification=inotify
>>  --with-modules --with-jpeg --with-tiff --with-gif --with-png
>>  --with-webp --with-xpm --with-rsvg --without-imagemagick --with-xml2
>                ^^^^^^^^^^
>>  --with-gnutls --with-sound --with-m17n-flt --with-json --with-harfbuzz
>>  --with-cairo --with-libgmp --with-sqlite3 --with-tree-sitter
>>  --with-native-compilation=aot 'CFLAGS=-fno-PIE -mtune=generic -O2 -pipe
>>  -g -ffile-prefix-map=/builddir/emacs-29.4=.' 'CPPFLAGS= '
>>  'LDFLAGS=-no-pie -Wl,--as-needed ''
>
> But the features actually available to Emacs don't include XPM:
>
>> Configured features:
>> ACL CAIRO DBUS FREETYPE GIF GLIB GMP GNUTLS GSETTINGS HARFBUZZ JPEG JSON
>> LCMS2 LIBOTF LIBXML2 MODULES NATIVE_COMP NOTIFY INOTIFY PDUMPER PGTK PNG
>> RSVG SECCOMP SOUND SQLITE3 THREADS TIFF TOOLKIT_SCROLL_BARS TREE_SITTER
>> WEBP XIM GTK3 ZLIB
>
> So I wonder how this happened.
>
> Did you build Emacs yourself, or was it installed from some distro?

The PGTK configuration always enables Emacs's built-in XPM library (in
image.c).

All the same, the OP's problem is that the gdk-pixbuf library invoked by
the toolkit to load tool-bar images no longer enables XPM support by
default, because, in their words, it was "not being used."  Someone must
volunteer to enable loading tool-bar images with Emacs's image system
instead.