The ansi does not allow to use type declaration in loop that make the code
easier to read. And the GTK3 build fails with strict prototypes enabled.
# normal compiler flags
CFLAGS += $(shell pkg-config --cflags $(LIBS))
-CFLAGS += -Wall -pipe -std=c99 -ansi -Wstrict-prototypes
+CFLAGS += -Wall -pipe -std=c99
CFLAGS += -Wno-overlength-strings -Werror=format-security
CFLAGS += ${CPPFLAGS}
LDFLAGS += ${LIBFLAGS}