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Diffstat (limited to 'kernel/scripts/Kbuild.include')
| -rw-r--r-- | kernel/scripts/Kbuild.include | 305 |
1 files changed, 305 insertions, 0 deletions
diff --git a/kernel/scripts/Kbuild.include b/kernel/scripts/Kbuild.include new file mode 100644 index 000000000..d3437b82a --- /dev/null +++ b/kernel/scripts/Kbuild.include @@ -0,0 +1,305 @@ +#### +# kbuild: Generic definitions + +# Convenient variables +comma := , +quote := " +squote := ' +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 $(comma),_,$(dot-target).d) + +### +# filename of target with directory and extension stripped +basetarget = $(basename $(notdir $@)) + +### +# filename of first prerequisite with directory and extension stripped +baseprereq = $(basename $(notdir $<)) + +### +# Escape single quote for use in echo statements +escsq = $(subst $(squote),'\$(squote)',$1) + +### +# 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: +# define filechk_sample +# echo $KERNELRELEASE +# endef +# version.h : Makefile +# $(call filechk,sample) +# The rule defined shall write to stdout the content of the new file. +# The existing file will be compared with the new one. +# - If no file exist it is created +# - If the content differ the new file is used +# - If they are equal no change, and no timestamp update +# - stdin is piped in from the first prerequisite ($<) 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 $@; \ + fi +endef + +###### +# gcc support functions +# See documentation in Documentation/kbuild/makefiles.txt + +# 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))) + +# output directory for tests below +TMPOUT := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/) + +# try-run +# Usage: option = $(call try-run, $(CC)...-o "$$TMP",option-ok,otherwise) +# Exit code chooses option. "$$TMP" is can be used as temporary file and +# is automatically cleaned up. +try-run = $(shell set -e; \ + TMP="$(TMPOUT).$$$$.tmp"; \ + TMPO="$(TMPOUT).$$$$.o"; \ + if ($(1)) >/dev/null 2>&1; \ + then echo "$(2)"; \ + else echo "$(3)"; \ + fi; \ + rm -f "$$TMP" "$$TMPO") + +# as-option +# Usage: cflags-y += $(call as-option,-Wa$(comma)-isa=foo,) + +as-option = $(call try-run,\ + $(CC) $(KBUILD_CFLAGS) $(1) -c -x assembler /dev/null -o "$$TMP",$(1),$(2)) + +# as-instr +# Usage: cflags-y += $(call as-instr,instr,option1,option2) + +as-instr = $(call try-run,\ + printf "%b\n" "$(1)" | $(CC) $(KBUILD_AFLAGS) -c -x assembler -o "$$TMP" -,$(2),$(3)) + +# cc-option +# Usage: cflags-y += $(call cc-option,-march=winchip-c6,-march=i586) + +cc-option = $(call try-run,\ + $(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",$(1),$(2)) + +# cc-option-yn +# Usage: flag := $(call cc-option-yn,-march=winchip-c6) +cc-option-yn = $(call try-run,\ + $(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",y,n) + +# cc-option-align +# Prefix align with either -falign or -malign +cc-option-align = $(subst -functions=0,,\ + $(call cc-option,-falign-functions=0,-malign-functions=0)) + +# cc-disable-warning +# Usage: cflags-y += $(call cc-disable-warning,unused-but-set-variable) +cc-disable-warning = $(call try-run,\ + $(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1))) + +# cc-version +cc-version = $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-version.sh $(CC)) + +# cc-fullversion +cc-fullversion = $(shell $(CONFIG_SHELL) \ + $(srctree)/scripts/gcc-version.sh -p $(CC)) + +# cc-ifversion +# Usage: EXTRA_CFLAGS += $(call cc-ifversion, -lt, 0402, -O1) +cc-ifversion = $(shell [ $(cc-version) $(1) $(2) ] && echo $(3) || echo $(4)) + +# cc-ldoption +# Usage: ldflags += $(call cc-ldoption, -Wl$(comma)--hash-style=both) +cc-ldoption = $(call try-run,\ + $(CC) $(1) -nostdlib -x c /dev/null -o "$$TMP",$(1),$(2)) + +# ld-option +# Usage: LDFLAGS += $(call ld-option, -X) +ld-option = $(call try-run,\ + $(CC) -x c /dev/null -c -o "$$TMPO" ; $(LD) $(1) "$$TMPO" -o "$$TMP",$(1),$(2)) + +# ar-option +# Usage: KBUILD_ARFLAGS := $(call ar-option,D) +# Important: no spaces around options +ar-option = $(call try-run, $(AR) rc$(1) "$$TMP",$(1),$(2)) + +# ld-version +# Note this is mainly for HJ Lu's 3 number binutil versions +ld-version = $(shell $(LD) --version | $(srctree)/scripts/ld-version.sh) + +# ld-ifversion +# Usage: $(call ld-ifversion, -ge, 22252, y) +ld-ifversion = $(shell [ $(ld-version) $(1) $(2) ] && echo $(3) || echo $(4)) + +###### + +### +# 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.modbuiltin obj= +# Usage: +# $(Q)$(MAKE) $(modbuiltin)=dir +modbuiltin := -f $(srctree)/scripts/Makefile.modbuiltin obj + +### +# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.dtbinst obj= +# Usage: +# $(Q)$(MAKE) $(dtbinst)=dir +dtbinst := -f $(if $(KBUILD_SRC),$(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 + +### +# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.headersinst obj= +# Usage: +# $(Q)$(MAKE) $(hdr-inst)=dir +hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj + +# Prefix -I with $(srctree) if it is not an absolute path. +# skip if -I has no parameter +addtree = $(if $(patsubst -I%,%,$(1)), \ +$(if $(filter-out -I/%,$(1)),$(patsubst -I%,-I$(srctree)/%,$(1))) $(1)) + +# Find all -I options and call addtree +flags = $(foreach o,$($(1)),$(if $(filter -I%,$(o)),$(call addtree,$(o)),$(o))) + +# 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)';) + +# 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))) + +### +# 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.txt for more info + +ifneq ($(KBUILD_NOCMDDEP),1) +# Check if both arguments has same arguments. Result is empty string if equal. +# User may override this check using make KBUILD_NOCMDDEP=1 +arg-check = $(strip $(filter-out $(cmd_$(1)), $(cmd_$@)) \ + $(filter-out $(cmd_$@), $(cmd_$(1))) ) +else +arg-check = $(if $(strip $(cmd_$@)),,1) +endif + +# Replace >$< with >$$< to preserve $ when reloading the .cmd file +# (needed for make) +# Replace >#< with >\#< 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 \#,\\\#,$(subst $$,$$$$,$(cmd_$(1))))) + +# 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 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) + +# 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) + +# 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))) + +### +# 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 |