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