diff options
Diffstat (limited to 'scripts/Kbuild.include')
| -rw-r--r-- | scripts/Kbuild.include | 93 |
1 files changed, 70 insertions, 23 deletions
diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include index bb19c1561f1..3d523899fdc 100644 --- a/scripts/Kbuild.include +++ b/scripts/Kbuild.include @@ -8,9 +8,13 @@ empty := space := $(empty) $(empty) ### +# Name of target with a '.' as filename prefix. foo/bar.o => foo/.bar.o +dot-target = $(dir $@).$(notdir $@) + +### # The temporary file to save gcc -MD generated dependencies must not # contain a comma -depfile = $(subst $(comma),_,$(@D)/.$(@F).d) +depfile = $(subst $(comma),_,$(dot-target).d) ### # filename of target with directory and extension stripped @@ -119,40 +123,83 @@ objectify = $(foreach o,$(1),$(if $(filter /%,$(o)),$(o),$(obj)/$(o))) ifneq ($(KBUILD_NOCMDDEP),1) # Check if both arguments has same arguments. Result in empty string if equal # User may override this check using make KBUILD_NOCMDDEP=1 -arg-check = $(strip $(filter-out $(1), $(2)) $(filter-out $(2), $(1)) ) +arg-check = $(strip $(filter-out $(cmd_$(1)), $(cmd_$@)) \ + $(filter-out $(cmd_$@), $(cmd_$(1))) ) endif # echo command. Short version is $(quiet) equals quiet, otherwise full command echo-cmd = $(if $($(quiet)cmd_$(1)), \ - echo ' $(call escsq,$($(quiet)cmd_$(1)))';) + echo ' $(call escsq,$($(quiet)cmd_$(1)))$(echo-why)';) +# >'< substitution is for echo to work, +# >$< substitution to preserve $ when reloading .cmd file +# note: when using inline perl scripts [perl -e '...$$t=1;...'] +# in $(cmd_xxx) double $$ your perl vars make-cmd = $(subst \#,\\\#,$(subst $$,$$$$,$(call escsq,$(cmd_$(1))))) -# function to only execute the passed command if necessary -# >'< substitution is for echo to work, >$< substitution to preserve $ when reloading .cmd file -# note: when using inline perl scripts [perl -e '...$$t=1;...'] in $(cmd_xxx) double $$ your perl vars +# Find any prerequisites that is newer than target or that does not exist. +# PHONY targets skipped in both cases. +any-prereq = $(filter-out $(PHONY),$?) $(filter-out $(PHONY) $(wildcard $^),$^) + +# Execute command if command has changed or prerequisitei(s) are updated # -if_changed = $(if $(strip $(filter-out $(PHONY),$?) \ - $(call arg-check, $(cmd_$(1)), $(cmd_$@)) ), \ - @set -e; \ - $(echo-cmd) $(cmd_$(1)); \ - echo 'cmd_$@ := $(make-cmd)' > $(@D)/.$(@F).cmd) +if_changed = $(if $(strip $(any-prereq) $(arg-check)), \ + @set -e; \ + $(echo-cmd) $(cmd_$(1)); \ + echo 'cmd_$@ := $(make-cmd)' > $(dot-target).cmd) # execute the command and also postprocess generated .d dependencies # file -if_changed_dep = $(if $(strip $(filter-out $(PHONY),$?) \ - $(filter-out FORCE $(wildcard $^),$^) \ - $(call arg-check, $(cmd_$(1)), $(cmd_$@)) ), \ - @set -e; \ - $(echo-cmd) $(cmd_$(1)); \ - scripts/basic/fixdep $(depfile) $@ '$(make-cmd)' > $(@D)/.$(@F).tmp; \ - rm -f $(depfile); \ - mv -f $(@D)/.$(@F).tmp $(@D)/.$(@F).cmd) +if_changed_dep = $(if $(strip $(any-prereq) $(arg-check) ), \ + @set -e; \ + $(echo-cmd) $(cmd_$(1)); \ + scripts/basic/fixdep $(depfile) $@ '$(make-cmd)' > $(dot-target).tmp;\ + rm -f $(depfile); \ + mv -f $(dot-target).tmp $(dot-target).cmd) # Usage: $(call if_changed_rule,foo) # will check if $(cmd_foo) changed, or any of the prequisites changed, # and if so will execute $(rule_foo) -if_changed_rule = $(if $(strip $(filter-out $(PHONY),$?) \ - $(call arg-check, $(cmd_$(1)), $(cmd_$@)) ),\ - @set -e; \ - $(rule_$(1))) +if_changed_rule = $(if $(strip $(any-prereq) $(arg-check) ), \ + @set -e; \ + $(rule_$(1))) + +### +# why - tell why a a target got build +# 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 $(strip $(any-prereq)),- due to: $(any-prereq), \ + $(if $(arg-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 |