diff options
Diffstat (limited to 'scripts/Kbuild.include')
-rw-r--r-- | scripts/Kbuild.include | 123 |
1 files changed, 61 insertions, 62 deletions
diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include index 919f286162..838ab11e7c 100644 --- a/scripts/Kbuild.include +++ b/scripts/Kbuild.include @@ -1,3 +1,4 @@ +# SPDX-License-Identifier: GPL-2.0 #### # kbuild: Generic definitions @@ -24,10 +25,18 @@ depfile = $(subst $(comma),_,$(dot-target).d) 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 @@ -37,11 +46,11 @@ kecho := $($(quiet)kecho) ### # filechk is used to check if the content of a generated file is updated. # Sample usage: -# define filechk_sample -# echo $KERNELRELEASE -# endef -# version.h : Makefile +# +# 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 @@ -50,32 +59,31 @@ kecho := $($(quiet)kecho) # - stdin is piped in from the first prerequisite ($<) so one has # to specify a valid file as first prerequisite (often the kbuild file) define filechk - $(Q)set -e; \ - $(kecho) ' CHK $@'; \ - mkdir -p $(dir $@); \ - $(filechk_$(1)) < $< > $@.tmp; \ - if [ -r $@ ] && cmp -s $@ $@.tmp; then \ - rm -f $@.tmp; \ - else \ - $(kecho) ' UPD $@'; \ - mv -f $@.tmp $@; \ + $(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 ###### # gcc support functions -# See documentation in Documentation/kbuild/makefiles.txt +# See documentation in Documentation/kbuild/makefiles.rst # cc-cross-prefix # Usage: CROSS_COMPILE := $(call cc-cross-prefix, m68k-linux-gnu- m68k-linux-) -# Return first prefix where a prefix$(CC) is found in PATH. -# If no $(CC) found in PATH with listed prefixes return nothing -cc-cross-prefix = \ - $(word 1, $(foreach c,$(1), \ - $(shell set -e; \ - if (which $(strip $(c))$(CC)) > /dev/null 2>&1 ; then \ - echo $(c); \ - fi))) +# Return first <prefix> where a <prefix>gcc is found in PATH. +# If no gcc found in PATH with listed prefixes return nothing +# +# Note: '2>/dev/null' is here to force Make to invoke a shell. Otherwise, it +# would try to directly execute the shell builtin 'command'. This workaround +# should be kept for a long time since this issue was fixed only after the +# GNU Make 4.2.1 release. +cc-cross-prefix = $(firstword $(foreach c, $(1), \ + $(if $(shell command -v -- $(c)gcc 2>/dev/null), $(c)))) # output directory for tests below TMPOUT := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/) @@ -97,7 +105,7 @@ try-run = $(shell set -e; \ # Usage: cflags-y += $(call as-option,-Wa$(comma)-isa=foo,) as-option = $(call try-run,\ - $(CC) $(CFLAGS) $(1) -c -xassembler /dev/null -o "$$TMP",$(1),$(2)) + $(CC) $(KBUILD_CFLAGS) $(1) -c -xassembler /dev/null -o "$$TMP",$(1),$(2)) # as-instr # Usage: cflags-y += $(call as-instr,instr,option1,option2) @@ -109,17 +117,17 @@ as-instr = $(call try-run,\ # Usage: cflags-y += $(call cc-option,-march=winchip-c6,-march=i586) cc-option = $(call try-run,\ - $(CC) -Werror $(KBUILD_CPPFLAGS) $(CFLAGS) $(1) -c -xc /dev/null -o "$$TMP",$(1),$(2)) + $(CC) -Werror $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(1) -c -xc /dev/null -o "$$TMP",$(1),$(2)) # cc-option-yn # Usage: flag := $(call cc-option-yn,-march=winchip-c6) cc-option-yn = $(call try-run,\ - $(CC) -Werror $(KBUILD_CPPFLAGS) $(CFLAGS) $(1) -c -xc /dev/null -o "$$TMP",y,n) + $(CC) -Werror $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(1) -c -xc /dev/null -o "$$TMP",y,n) # cc-disable-warning # Usage: cflags-y += $(call cc-disable-warning,unused-but-set-variable) cc-disable-warning = $(call try-run,\ - $(CC) -Werror $(KBUILD_CPPFLAGS) $(CFLAGS) -W$(strip $(1)) -c -xc /dev/null -o "$$TMP",-Wno-$(strip $(1))) + $(CC) -Werror $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -W$(strip $(1)) -c -xc /dev/null -o "$$TMP",-Wno-$(strip $(1))) # cc-version # Usage gcc-ver := $(call cc-version) @@ -130,7 +138,7 @@ cc-version = $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-version.sh $(CC)) cc-ifversion = $(shell [ $(call cc-version, $(CC)) $(1) $(2) ] && echo $(3)) # ld-option -# Usage: LDFLAGS += $(call ld-option, -X) +# Usage: KBUILD_LDFLAGS += $(call ld-option, -X) ld-option = $(call try-run,\ $(CC) -x c /dev/null -c -o "$$TMPO" ; $(LD) $(1) "$$TMPO" -o "$$TMP",$(1),$(2)) @@ -140,18 +148,13 @@ ld-option = $(call try-run,\ # Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj= # Usage: # $(Q)$(MAKE) $(build)=dir -build := -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.build obj +build := -f $(srctree)/scripts/Makefile.build obj ### -# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.modbuiltin obj= -# Usage: -# $(Q)$(MAKE) $(modbuiltin)=dir -modbuiltin := -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.modbuiltin obj - -# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.clean obj=dir +# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.clean obj= # Usage: # $(Q)$(MAKE) $(clean)=dir -clean := -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.clean obj +clean := -f $(srctree)/scripts/Makefile.clean obj # Prefix -I with $(srctree) if it is not an absolute path. # skip if -I has no parameter @@ -167,10 +170,7 @@ echo-cmd = $(if $($(quiet)cmd_$(1)),\ echo ' $(call escsq,$($(quiet)cmd_$(1)))$(echo-why)';) # printing commands -cmd = @$(echo-cmd) $(cmd_$(1)) - -# Add $(obj)/ for paths that are not absolute -objectify = $(foreach o,$(1),$(if $(filter /%,$(o)),$(o),$(obj)/$(o))) +cmd = @set -e; $(echo-cmd) $(cmd_$(1)) ### # if_changed - execute command if any prerequisite is newer than @@ -178,15 +178,15 @@ objectify = $(foreach o,$(1),$(if $(filter /%,$(o)),$(o),$(obj)/$(o))) # 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.txt for more info +# See Documentation/kbuild/makefiles.rst for more info ifneq ($(KBUILD_NOCMDDEP),1) -# Check if both arguments are the same including their order. Result is empty +# 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 -arg-check = $(filter-out $(subst $(space),$(space_escape),$(strip $(cmd_$@))), \ +cmd-check = $(filter-out $(subst $(space),$(space_escape),$(strip $(cmd_$@))), \ $(subst $(space),$(space_escape),$(strip $(cmd_$1)))) else -arg-check = $(if $(strip $(cmd_$@)),,1) +cmd-check = $(if $(strip $(cmd_$@)),,1) endif # Replace >$< with >$$< to preserve $ when reloading the .cmd file @@ -197,34 +197,33 @@ endif # (needed for the shell) make-cmd = $(call escsq,$(subst $(pound),$$(pound),$(subst $$,$$$$,$(cmd_$(1))))) -# Find any prerequisites that is newer than target or that does not exist. +# 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. -any-prereq = $(filter-out $(PHONY),$?) $(filter-out $(PHONY) $(wildcard $^),$^) +newer-prereqs = $(filter-out $(PHONY),$?) # Execute command if command has changed or prerequisite(s) are updated. -# -if_changed = $(if $(strip $(any-prereq) $(arg-check)), \ - @set -e; \ - $(echo-cmd) $(cmd_$(1)); \ - printf '%s\n' 'cmd_$@ := $(make-cmd)' > $(dot-target).cmd) +if_changed = $(if $(newer-prereqs)$(cmd-check), \ + $(cmd); \ + printf '%s\n' 'cmd_$@ := $(make-cmd)' > $(dot-target).cmd, @:) # Execute the command and also postprocess generated .d dependencies file. -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) +if_changed_dep = $(if $(newer-prereqs)$(cmd-check),$(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 $(strip $(any-prereq) $(arg-check) ), \ - @set -e; \ - $(rule_$(1))) +if_changed_rule = $(if $(newer-prereqs)$(cmd-check),$(rule_$(1)),@:) ### -# why - tell why a a target got build +# 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 @@ -246,8 +245,8 @@ 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 $(newer-prereqs),- due to: $(newer-prereqs), \ + $(if $(cmd-check), \ $(if $(cmd_$@),- due to command line change, \ $(if $(filter $@, $(targets)), \ - due to missing .cmd file, \ |