checkheader libxml2-dev libxml/xpath.h xmlXPathInit "$(CPPFLAGS_XML)" "$(LIBS_XML)"; \
checkheader libpng12-dev png.h png_create_read_struct "$(CPPFLAGS_PNG)" "$(LIBS_PNG)"; \
checkheader "mesa-common-dev (or another OpenGL library)" GL/gl.h glClear "$(CPPFLAGS_GL)" "$(LIBS_GL)"; \
checkheader libxml2-dev libxml/xpath.h xmlXPathInit "$(CPPFLAGS_XML)" "$(LIBS_XML)"; \
checkheader libpng12-dev png.h png_create_read_struct "$(CPPFLAGS_PNG)" "$(LIBS_PNG)"; \
checkheader "mesa-common-dev (or another OpenGL library)" GL/gl.h glClear "$(CPPFLAGS_GL)" "$(LIBS_GL)"; \