gdk-pixbuf2 broken on macppc (all powerpc?)

"graphics/gdk-pixbuf2" builds and installs on macppc-current (first with
GCC8 and now with GCC9), but attempts to use it result in a segfault.
Example from "graphics/librsvg-c":

[...]
Making all in gdk-pixbuf-loader
gmake[2]: Entering directory '/var/tmp/pkgsrc/graphics/librsvg-c/work/librsvg-2.40.21/gdk-pixbuf-loader'
  GEN      gdk-pixbuf-loaders
gmake[2]: *** [Makefile:870: gdk-pixbuf-loaders] Segmentation fault (core dumped)
gmake[2]: Leaving directory '/var/tmp/pkgsrc/graphics/librsvg-c/work/librsvg-2.40.21/gdk-pixbuf-loader'
[...]

Each instance results in the following message on the console:

[<timestamp>] trap: pid <pid>.<pid> (gdk-pixbuf-query): user read DSI trap @ 0 by 0xfd4505d4 (DISR 0x40000000, err=14)

A "gdk-pixbuf-query.core" file is left behind, but there is no executable
with that name.  The only executable close to that name is
"/usr/pkg/bin/gdk-pixbuf-query-loaders"

Curiously, the first such instance of that core file is in
"/var/db/pkg/gdk-pixbuf2-2.40.0nb1" immediately after the package metadata
files are written upon installation/update.


An apparently related problem occurs when trying to build "x11/gtk2":

[...]
Making all in demos
gmake[2]: Entering directory '/var/tmp/pkgsrc/x11/gtk2/work/gtk+-2.24.32/demos'
/usr/pkg/bin/gdk-pixbuf-csource --raw --build-list              \
        apple_red  ./apple-red.png      \
                gnome_foot ./gnome-foot.png     \
        > test-inline-pixbufs.h                         \
|| (rm -f test-inline-pixbufs.h && false)
failed to load "./apple-red.png": Couldnât recognize the image file format for file â./apple-red.pngâ
gmake[2]: *** [Makefile:1018: test-inline-pixbufs.h] Error 1
gmake[2]: Leaving directory '/var/tmp/pkgsrc/x11/gtk2/work/gtk+-2.24.32/demos'
[...]
-- 
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