* Makefile.am (MODULES): Add libpng.scm.
@ -85,6 +85,7 @@ MODULES = \
gnu/packages/libffi.scm \
gnu/packages/libidn.scm \
gnu/packages/libjpeg.scm \
gnu/packages/libpng.scm \
gnu/packages/libsigsegv.scm \
gnu/packages/libtiff.scm \
gnu/packages/libunistring.scm \