Makefile with flags

Hi,

Small question regarding makefiles:
I want to add a new target: release
that will compile my driver with additional flag
(EXTRA_CFLAGS += -Drelease_flag)

how can i do that on this example:

Code:

KERNELPATH := /home/kernel-2.6.24/

.PHONY: all clean

EXTRA_CFLAGS += -Werror
EXTRA_CFLAGS += -I$(src)/dir1
EXTRA_CFLAGS += -I$(src)/dir2

all: modules

obj-m := driver.o

driver-objs := file1.o
driver-objs += file2.o

modules:
 make -C $(KERNELPATH) M=$(PWD) modules

clean:
 make -C $(KERNELPATH) M=$(PWD) clean

thanks

Originally Posted by amitbern

Hi,

Small question regarding makefiles:
I want to add a new target: release
that will compile my driver with additional flag
(EXTRA_CFLAGS += -Drelease_flag)

Recursively invoke make.

Code:

...
EXTRA_CFLAGS += -Werror
EXTRA_CFLAGS += -I$(src)/dir1
EXTRA_CFLAGS += -I$(src)/dir2
EXTRA_CFLAGS += $BUILD_CONFIG_FLAGS
...

release:
        $(MAKE) all BUILD_CONFIG_FLAGS=-Drelease_flag
...

EDIT: The problem is that the makefile is not aware that you've changed your flags, so it won't rebuild if you've already built some other configuration. You have to "make clean" first. There are ways to set it up automatically but they are more complicated than what I've shown here, involving external scripts, etc.