232 lines
		
	
	
		
			8.3 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
			
		
		
	
	
			232 lines
		
	
	
		
			8.3 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
| # SPDX-License-Identifier: GPL-2.0
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| ####
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| # kbuild: Generic definitions
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| 
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| # Convenient variables
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| comma   := ,
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| quote   := "
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| squote  := '
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| empty   :=
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| space   := $(empty) $(empty)
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| space_escape := _-_SPACE_-_
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| pound := \#
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| 
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| ###
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| # Name of target with a '.' as filename prefix. foo/bar.o => foo/.bar.o
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| dot-target = $(dir $@).$(notdir $@)
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| 
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| ###
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| # Name of target with a '.tmp_' as filename prefix. foo/bar.o => foo/.tmp_bar.o
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| tmp-target = $(dir $@).tmp_$(notdir $@)
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| 
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| ###
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| # The temporary file to save gcc -MMD generated dependencies must not
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| # contain a comma
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| depfile = $(subst $(comma),_,$(dot-target).d)
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| 
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| ###
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| # filename of target with directory and extension stripped
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| basetarget = $(basename $(notdir $@))
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| 
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| ###
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| # real prerequisites without phony targets
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| real-prereqs = $(filter-out $(PHONY), $^)
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| 
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| ###
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| # Escape single quote for use in echo statements
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| escsq = $(subst $(squote),'\$(squote)',$1)
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| 
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| ###
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| # Quote a string to pass it to C files. foo => '"foo"'
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| stringify = $(squote)$(quote)$1$(quote)$(squote)
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| 
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| ###
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| # Easy method for doing a status message
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|        kecho := :
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|  quiet_kecho := echo
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| silent_kecho := :
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| kecho := $($(quiet)kecho)
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| 
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| ###
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| # filechk is used to check if the content of a generated file is updated.
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| # Sample usage:
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| #
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| # filechk_sample = echo $(KERNELRELEASE)
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| # version.h: FORCE
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| #	$(call filechk,sample)
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| #
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| # The rule defined shall write to stdout the content of the new file.
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| # The existing file will be compared with the new one.
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| # - If no file exist it is created
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| # - If the content differ the new file is used
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| # - If they are equal no change, and no timestamp update
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| define filechk
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| 	$(check-FORCE)
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| 	$(Q)set -e;						\
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| 	mkdir -p $(dir $@);					\
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| 	trap "rm -f $(dot-target).tmp" EXIT;			\
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| 	{ $(filechk_$(1)); } > $(dot-target).tmp;		\
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| 	if [ ! -r $@ ] || ! cmp -s $@ $(dot-target).tmp; then	\
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| 		$(kecho) '  UPD     $@';			\
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| 		mv -f $(dot-target).tmp $@;			\
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| 	fi
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| endef
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| 
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| ###
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| # Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj=
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| # Usage:
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| # $(Q)$(MAKE) $(build)=dir
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| build := -f $(srctree)/scripts/Makefile.build obj
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| 
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| ###
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| # Shorthand for $(Q)$(MAKE) -f scripts/Makefile.dtbinst obj=
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| # Usage:
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| # $(Q)$(MAKE) $(dtbinst)=dir
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| dtbinst := -f $(srctree)/scripts/Makefile.dtbinst obj
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| 
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| ###
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| # Shorthand for $(Q)$(MAKE) -f scripts/Makefile.clean obj=
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| # Usage:
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| # $(Q)$(MAKE) $(clean)=dir
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| clean := -f $(srctree)/scripts/Makefile.clean obj
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| 
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| # echo command.
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| # Short version is used, if $(quiet) equals `quiet_', otherwise full one.
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| echo-cmd = $(if $($(quiet)cmd_$(1)),\
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| 	echo '  $(call escsq,$($(quiet)cmd_$(1)))$(echo-why)';)
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| 
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| # sink stdout for 'make -s'
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|        redirect :=
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|  quiet_redirect :=
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| silent_redirect := exec >/dev/null;
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| 
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| # Delete the target on interruption
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| #
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| # GNU Make automatically deletes the target if it has already been changed by
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| # the interrupted recipe. So, you can safely stop the build by Ctrl-C (Make
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| # will delete incomplete targets), and resume it later.
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| #
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| # However, this does not work when the stderr is piped to another program, like
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| #  $ make >&2 | tee log
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| # Make dies with SIGPIPE before cleaning the targets.
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| #
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| # To address it, we clean the target in signal traps.
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| #
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| # Make deletes the target when it catches SIGHUP, SIGINT, SIGQUIT, SIGTERM.
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| # So, we cover them, and also SIGPIPE just in case.
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| #
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| # Of course, this is unneeded for phony targets.
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| delete-on-interrupt = \
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| 	$(if $(filter-out $(PHONY), $@), \
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| 		$(foreach sig, HUP INT QUIT TERM PIPE, \
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| 			trap 'rm -f $@; trap - $(sig); kill -s $(sig) $$$$' $(sig);))
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| 
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| # printing commands
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| cmd = @set -e; $(echo-cmd) $($(quiet)redirect) $(delete-on-interrupt) $(cmd_$(1))
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| 
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| ###
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| # if_changed      - execute command if any prerequisite is newer than
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| #                   target, or command line has changed
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| # if_changed_dep  - as if_changed, but uses fixdep to reveal dependencies
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| #                   including used config symbols
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| # if_changed_rule - as if_changed but execute rule instead
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| # See Documentation/kbuild/makefiles.rst for more info
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| 
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| ifneq ($(KBUILD_NOCMDDEP),1)
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| # Check if both commands are the same including their order. Result is empty
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| # string if equal. User may override this check using make KBUILD_NOCMDDEP=1
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| cmd-check = $(filter-out $(subst $(space),$(space_escape),$(strip $(cmd_$@))), \
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|                          $(subst $(space),$(space_escape),$(strip $(cmd_$1))))
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| else
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| cmd-check = $(if $(strip $(cmd_$@)),,1)
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| endif
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| 
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| # Replace >$< with >$$< to preserve $ when reloading the .cmd file
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| # (needed for make)
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| # Replace >#< with >$(pound)< to avoid starting a comment in the .cmd file
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| # (needed for make)
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| # Replace >'< with >'\''< to be able to enclose the whole string in '...'
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| # (needed for the shell)
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| make-cmd = $(call escsq,$(subst $(pound),$$(pound),$(subst $$,$$$$,$(cmd_$(1)))))
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| 
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| # Find any prerequisites that are newer than target or that do not exist.
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| # (This is not true for now; $? should contain any non-existent prerequisites,
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| # but it does not work as expected when .SECONDARY is present. This seems a bug
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| # of GNU Make.)
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| # PHONY targets skipped in both cases.
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| newer-prereqs = $(filter-out $(PHONY),$?)
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| 
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| # It is a typical mistake to forget the FORCE prerequisite. Check it here so
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| # no more breakage will slip in.
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| check-FORCE = $(if $(filter FORCE, $^),,$(warning FORCE prerequisite is missing))
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| 
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| if-changed-cond = $(newer-prereqs)$(cmd-check)$(check-FORCE)
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| 
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| # Execute command if command has changed or prerequisite(s) are updated.
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| if_changed = $(if $(if-changed-cond),$(cmd_and_savecmd),@:)
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| 
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| cmd_and_savecmd =                                                            \
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| 	$(cmd);                                                              \
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| 	printf '%s\n' 'cmd_$@ := $(make-cmd)' > $(dot-target).cmd
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| 
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| # Execute the command and also postprocess generated .d dependencies file.
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| if_changed_dep = $(if $(if-changed-cond),$(cmd_and_fixdep),@:)
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| 
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| cmd_and_fixdep =                                                             \
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| 	$(cmd);                                                              \
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| 	scripts/basic/fixdep $(depfile) $@ '$(make-cmd)' > $(dot-target).cmd;\
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| 	rm -f $(depfile)
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| 
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| # Usage: $(call if_changed_rule,foo)
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| # Will check if $(cmd_foo) or any of the prerequisites changed,
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| # and if so will execute $(rule_foo).
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| if_changed_rule = $(if $(if-changed-cond),$(rule_$(1)),@:)
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| 
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| ###
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| # why - tell why a target got built
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| #       enabled by make V=2
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| #       Output (listed in the order they are checked):
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| #          (1) - due to target is PHONY
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| #          (2) - due to target missing
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| #          (3) - due to: file1.h file2.h
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| #          (4) - due to command line change
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| #          (5) - due to missing .cmd file
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| #          (6) - due to target not in $(targets)
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| # (1) PHONY targets are always build
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| # (2) No target, so we better build it
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| # (3) Prerequisite is newer than target
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| # (4) The command line stored in the file named dir/.target.cmd
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| #     differed from actual command line. This happens when compiler
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| #     options changes
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| # (5) No dir/.target.cmd file (used to store command line)
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| # (6) No dir/.target.cmd file and target not listed in $(targets)
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| #     This is a good hint that there is a bug in the kbuild file
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| ifeq ($(KBUILD_VERBOSE),2)
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| why =                                                                        \
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|     $(if $(filter $@, $(PHONY)),- due to target is PHONY,                    \
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|         $(if $(wildcard $@),                                                 \
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|             $(if $(newer-prereqs),- due to: $(newer-prereqs),                \
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|                 $(if $(cmd-check),                                           \
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|                     $(if $(cmd_$@),- due to command line change,             \
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|                         $(if $(filter $@, $(targets)),                       \
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|                             - due to missing .cmd file,                      \
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|                             - due to $(notdir $@) not in $$(targets)         \
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|                          )                                                   \
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|                      )                                                       \
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|                  )                                                           \
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|              ),                                                              \
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|              - due to target missing                                         \
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|          )                                                                   \
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|      )
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| 
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| echo-why = $(call escsq, $(strip $(why)))
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| endif
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| 
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| ###############################################################################
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| 
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| # delete partially updated (i.e. corrupted) files on error
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| .DELETE_ON_ERROR:
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| 
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| # do not delete intermediate files automatically
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| .SECONDARY:
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