There's a closed pull request on the void-packages repository

gimp: build with libexecinfo on musl
https://github.com/void-linux/void-packages/pull/11521
Description: Gimp unconditionally includes and uses execinfo.h in its app core library, which is used everywhere in gimp. If not installed, gimp will fail to compile. I'm actually not quite sure how it compiled for musl until now, but somehow it did.

See https://github.com/GNOME/gimp/blob/01f940990260146a860f6956ebd962b45b0fc961/app/core/gimpbacktrace-linux.c#L42