On 28/01/10 15:12, Guan Wang wrote:
Hi,I have a c file foo.c: int main(void) { #ifdef FOO printf("FOO!\n"); #endif #ifdef BAR printf("BAR!\n"); #endif return 0; } and a Makefile may be like this: CPPFLAGS=-DFOO a.out:foo.o gcc -o $@ $^ %.o:%.c gcc -c $< ${CPPFLAGS} if I make it and run a.out (I am on a GNU Make 3.81), the output is FOO!. If I want to print out BAR! or FOO!BAR!, I could always append - DBAR onto CPPFLAGS. So, my question is: what if I want to append -DBAR on the command line? I tried: make CPPFLAGS+=-DBAR But it will completely replace the defined CPPFLAGS in the Makefile. Obviously, the one defined on the command line has the precedence. Is this doable through command line arguments to make?
It is: cmd_line_cppflags_ := $(CPPFLAGS) override CPPFLAGS = -DFOO $(cmd_line_cppflags_) -- Max _______________________________________________ Help-make mailing list [email protected] http://lists.gnu.org/mailman/listinfo/help-make
