Your fix for this (e9ca57cfcbaf1a8dfc6bde5a2afd5f3c7b357cb1) causes the build to fail on Arch Linux.
Rolling back that change makes the build work again.
make[2]: Leaving directory '/home/emartenson/src/emacs/admin/charsets'
make -C ../admin/unidata charscript.el
make[2]: Entering directory '/home/emartenson/src/emacs/admin/unidata'
make[2]: Nothing to be done for 'charscript.el'.
make[2]: Leaving directory '/home/emartenson/src/emacs/admin/unidata'
CCLD temacs
/bin/ld: image.o: undefined reference to symbol 'png_longjmp@@PNG16_0'
/usr/lib/libpng16.so.16: error adding symbols: DSO missing from command line
collect2: error: ld returned 1 exit status
make[1]: *** [Makefile:606: temacs] Error 1
make[1]: Leaving directory '/home/emartenson/src/emacs/src'
make: *** [Makefile:418: src] Error 2