Makefile中嵌套和其他编译

顶级makefile

cc = gcc
all: this sub

export dd=debug


this:
    $(cc) test.c -o test
sub:
    make -C 1

下级

ifeq ("$(dd)","debug")
    cc=gcc -Wall
else
    cc=gcc
endif

all:
    $(cc) test.c -o test