/usr/lib/gnu-smalltalk/libSDL_mixer-1.2.so is in libsdl-mixer-gst 3.2.4-2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/gnu-smalltalk/../i386-linux-gnu/libSDL_mixer-1.2.so.0
/usr/lib/gnu-smalltalk/../i386-linux-gnu/libSDL_mixer-1.2.so.0