ref: e50e3e5a23b8f72d5f4809e1d9ceebe1c6cccaa8 dir: /GNUmakefile/
# GNU Make 3.x doesn't support the "!=" shell syntax, so here's an alternative PKG_CONFIG = pkg-config PNGFLAGS = $(shell ${PKG_CONFIG} --cflags libpng) include Makefile