Create file | Dependence on another header file included in the header file

Question

Suppose I have a rule below at Makefile.

test.o: test.cpp foo.h
        g++ -c -o test.o test.cpp

Now suppose that foo.hincludes bar.h, as shown below.

user $ head -n 5 foo.h
#include"bar.h"
/*
.
.
*/
user $  

Will it be built test.oagain if there is any change in bar.h?

Or should I specifically specify bar.hin the rule, as shown below:

test.o: test.cpp foo.h bar.h
        g++ -c -o test.o test.cpp

Answer 1

Will it be built test.oagain if there is any change in bar.h?

No. Make is unable to find out about this dependency or check for changes in #includes.

, , , : . (, GCC GNU .)

• .

• .

  SRCFILES := ...
  

• , .d SRCFILE.

  DEPFILES := $(patsubst %.cpp,%.d,$(SRCFILES))
  

• Makefile. ( - , Make , , , .)

  -include $(DEPFILES)
  

• , .

  %.o: %.cpp Makefile
      @$(CXX) $(CXXFLAGS) -MMD -MP -c $< -o $@
  

  -MMD make, () , , *.d. -MP , , .

Answer 2

GCC (, , Clang) ; , (cpp):

depend: .depend

.depend: $(SRC_FILES)
        rm -f ./.depend
        $(CC) $(CFLAGS) -MM $^ -MF  ./.depend;

include .depend

%.o: %.cpp
    $(CC) $(CFLAGS) -c $<

makedepend.