Creating a header file dependency.

[Palani Chinnakannan (pals)]

Hello,

                We are used to this concept of staging a set of header files from

our components during build.  So, each sub-system/component specifies

a list of header files that needs to be staged. They also specify a staging

directory. 

 

                Now, I am creating a dependency between the original header

and the staged header so that the staging takes place only when the

original header changes. (Otherwise, a blind copy breaks the

dependency and leads to unnecessary rebuilds.

 

       So, when I do this based on the following, I expect only the changed

file to be staged. However, looks like every file gets staged from a component

even though only one file is staged.

 

Here is my Makefile. When I do make all it  exports all file even if only

one file is changed.

 

# Default target must appear before any include lines

.PHONY: all

 

#

# Customizations for this local Makefile

 

EXPORT_HDR_PATH       := $(CLUSTER_OS_ROOT)/BUILD/inc/common/clos_sdk

 

EXPORT_HDRS                  := \

                                                                ../include/clos_api_socket_funcs.h \

                                                                ../include/clos_api_cerrno.h \

                                                                ../include/clos_api_services.h

 

EXPORT_LIB_PATH          :=

EXPORT_LIBS                     :=

 

EXPORTED_HDRS             := $(addprefix $(EXPORT_HDR_PATH)/,$(notdir $(EXPORT_HDRS)))

 

$(EXPORTED_HDRS): $(EXPORT_HDRS)

                @echo "updating header: $? ";

                cp $? $(EXPORT_HDR_PATH)

 

install: $(EXPORTED_HDRS)

 

all: install

 

clean:

                rm -f $(ARCH)/*

 

distclean: clean

                rm -f $(EXPORT_HDR_PATH)/*.h