-# flags
-CPPFLAGS = -DVERSION=\"${VERSION}\"
-CFLAGS = -g -std=c99 -pedantic -Wall -O0 ${INCS} ${CPPFLAGS}
-#CFLAGS = -std=c99 -pedantic -Wall -Os ${INCS} ${CPPFLAGS}
-LDFLAGS = -g ${LIBS}
-#LDFLAGS = -s ${LIBS}
+CPPFLAGS = -DVERSION=\"${VERSION}\" -D_GNU_SOURCE
+# -Wno-unused-function for routines not activated by user
+CFLAGS = -std=c99 -pedantic -Wno-unused-function -Wall -Wextra -Os ${INCS} ${CPPFLAGS}
+LDFLAGS = ${LIBS}