Re: rebuild when flags change

[Oleksandr Gavenko]

On 15.09.2010 6:44, Lynn Lin wrote:
> Hi all,
>        Our build command
>        $(QUIET_CPP)$(CPP) $(CPPFLAGS) $(CXXFLAGS) $(INCLUDES) -c $<
>
>        when CPPFLAGS change,how can we enable make rebuild?
I personally use such trick:

# Makefile itself.
MK_FILE := $(firstword $(MAKEFILE_LIST))
# Storage for CLI options.
MK_CLI_FILE := $(MK_FILE).cli

-include $(MK_CLI_FILE)
$(shell mkdir -p $(dir $(MK_CLI_FILE)); printf 
"DEBUG_OLD=$(DEBUG)\nOPT_LEVEL_OLD=$(OPT_LEVEL)\n" >$(MK_CLI_FILE))
ifneq '$(DEBUG_OLD)' '$(DEBUG)'
  $(shell touch $(MK_FILE))
endif
ifneq '$(OPT_LEVEL_OLD)' '$(OPT_LEVEL)'
  $(shell touch $(MK_FILE))
endif

and adds a lot of:

%.c: $(MK_FILE)
%.cxx: $(MK_FILE)
%.sh: $(MK_FILE)
...

--
С уважением, Александр Гавенко.