Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/shaggy...
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / scripts / Kbuild.include
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1####
2# kbuild: Generic definitions
3
5de043f4 4# Convenient constants
8ec4b4ff 5comma := ,
d51bfb78 6squote := '
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7empty :=
8space := $(empty) $(empty)
9
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10###
11# Name of target with a '.' as filename prefix. foo/bar.o => foo/.bar.o
12dot-target = $(dir $@).$(notdir $@)
13
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14###
15# The temporary file to save gcc -MD generated dependencies must not
16# contain a comma
48f1f058 17depfile = $(subst $(comma),_,$(dot-target).d)
8ec4b4ff 18
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19###
20# filename of target with directory and extension stripped
21basetarget = $(basename $(notdir $@))
22
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23###
24# Escape single quote for use in echo statements
25escsq = $(subst $(squote),'\$(squote)',$1)
26
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27###
28# filechk is used to check if the content of a generated file is updated.
29# Sample usage:
30# define filechk_sample
31# echo $KERNELRELEASE
32# endef
33# version.h : Makefile
34# $(call filechk,sample)
35# The rule defined shall write to stdout the content of the new file.
36# The existing file will be compared with the new one.
37# - If no file exist it is created
38# - If the content differ the new file is used
39# - If they are equal no change, and no timestamp update
40# - stdin is piped in from the first prerequisite ($<) so one has
41# to specify a valid file as first prerequisite (often the kbuild file)
42define filechk
43 $(Q)set -e; \
44 echo ' CHK $@'; \
45 mkdir -p $(dir $@); \
46 $(filechk_$(1)) < $< > $@.tmp; \
47 if [ -r $@ ] && cmp -s $@ $@.tmp; then \
48 rm -f $@.tmp; \
49 else \
50 echo ' UPD $@'; \
51 mv -f $@.tmp $@; \
52 fi
53endef
54
20a468b5 55######
9d6e7a70 56# gcc support functions
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57# See documentation in Documentation/kbuild/makefiles.txt
58
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59# checker-shell
60# Usage: option = $(call checker-shell, $(CC)...-o $$OUT, option-ok, otherwise)
61# Exit code chooses option. $$OUT is safe location for needless output.
62define checker-shell
63 $(shell set -e; \
64 DIR=$(KBUILD_EXTMOD); \
65 cd $${DIR:-$(objtree)}; \
66 OUT=$$PWD/.$$$$.null; \
67 \
68 ln -s /dev/null $$OUT; \
69 if $(1) >/dev/null 2>&1; \
70 then echo "$(2)"; \
71 else echo "$(3)"; \
72 fi; \
73 rm -f $$OUT)
74endef
347a00fb 75
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76# as-option
77# Usage: cflags-y += $(call as-option, -Wa$(comma)-isa=foo,)
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78as-option = $(call checker-shell, \
79 $(CC) $(CFLAGS) $(1) -c -xassembler /dev/null -o $$OUT, $(1), $(2))
20a468b5 80
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81# as-instr
82# Usage: cflags-y += $(call as-instr, instr, option1, option2)
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83as-instr = $(call checker-shell, \
84 printf "$(1)" | $(CC) $(AFLAGS) -c -xassembler -o $$OUT -, $(2), $(3))
e2414910 85
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86# cc-option
87# Usage: cflags-y += $(call cc-option, -march=winchip-c6, -march=i586)
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88cc-option = $(call checker-shell, \
89 $(CC) $(CFLAGS) $(if $(3),$(3),$(1)) -S -xc /dev/null -o $$OUT, $(1), $(2))
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90
91# cc-option-yn
92# Usage: flag := $(call cc-option-yn, -march=winchip-c6)
5de043f4 93cc-option-yn = $(call cc-option, "y", "n", $(1))
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94
95# cc-option-align
96# Prefix align with either -falign or -malign
97cc-option-align = $(subst -functions=0,,\
5de043f4 98 $(call cc-option,-falign-functions=0,-malign-functions=0))
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99
100# cc-version
101# Usage gcc-ver := $(call cc-version, $(CC))
8eb3afe0 102cc-version = $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-version.sh $(CC))
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103
104# cc-ifversion
105# Usage: EXTRA_CFLAGS += $(call cc-ifversion, -lt, 0402, -O1)
5de043f4 106cc-ifversion = $(shell [ $(call cc-version, $(CC)) $(1) $(2) ] && echo $(3))
20a468b5 107
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108# ld-option
109# Usage: ldflags += $(call ld-option, -Wl$(comma)--hash-style=both)
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110ld-option = $(call checker-shell, \
111 $(CC) $(1) -nostdlib -xc /dev/null -o $$OUT, $(1), $(2))
112
113######
0b0bf7a3 114
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115# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj=
116# Usage:
117# $(Q)$(MAKE) $(build)=dir
118build := -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.build obj
119
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120# Prefix -I with $(srctree) if it is not an absolute path,
121# add original to the end
122addtree = $(if \
123 $(filter-out -I/%, $(1)), $(patsubst -I%,-I$(srctree)/%,$(1))) $(1)
124
d9df92e2 125# Find all -I options and call addtree
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126flags = $(foreach o,$($(1)), \
127 $(if $(filter -I%,$(o)), $(call addtree, $(o)), $(o)))
d9df92e2 128
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129# echo command.
130# Short version is used, if $(quiet) equals `quiet_', otherwise full one.
131echo-cmd = $(if $($(quiet)cmd_$(1)), \
132 echo ' $(call escsq,$($(quiet)cmd_$(1)))$(echo-why)';)
133
134# printing commands
6176aa9a 135cmd = @$(echo-cmd) $(cmd_$(1))
8ec4b4ff 136
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137# Add $(obj)/ for paths that are not absolute
138objectify = $(foreach o,$(1), $(if $(filter /%,$(o)), $(o), $(obj)/$(o)))
0a504f25 139
8ec4b4ff 140###
5de043f4 141# if_changed - execute command if any prerequisite is newer than
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142# target, or command line has changed
143# if_changed_dep - as if_changed, but uses fixdep to reveal dependencies
144# including used config symbols
145# if_changed_rule - as if_changed but execute rule instead
146# See Documentation/kbuild/makefiles.txt for more info
147
148ifneq ($(KBUILD_NOCMDDEP),1)
5de043f4 149# Check if both arguments has same arguments. Result is empty string, if equal.
8ec4b4ff 150# User may override this check using make KBUILD_NOCMDDEP=1
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151arg-check = $(strip $(filter-out $(cmd_$(1)), $(cmd_$@)) \
152 $(filter-out $(cmd_$@), $(cmd_$(1))) )
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153endif
154
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155# >'< substitution is for echo to work,
156# >$< substitution to preserve $ when reloading .cmd file
157# note: when using inline perl scripts [perl -e '...$$t=1;...']
158# in $(cmd_xxx) double $$ your perl vars
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159make-cmd = $(subst \#,\\\#,$(subst $$,$$$$,$(call escsq,$(cmd_$(1)))))
160
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161# Find any prerequisites that is newer than target or that does not exist.
162# PHONY targets skipped in both cases.
163any-prereq = $(filter-out $(PHONY),$?) $(filter-out $(PHONY) $(wildcard $^),$^)
164
5de043f4 165# Execute command if command has changed or prerequisite(s) are updated.
4f193362 166#
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167if_changed = $(if $(strip $(any-prereq) $(arg-check)), \
168 @set -e; \
169 $(echo-cmd) $(cmd_$(1)); \
170 echo 'cmd_$@ := $(make-cmd)' > $(dot-target).cmd)
8ec4b4ff 171
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172# Execute the command and also postprocess generated .d dependencies file.
173#
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174if_changed_dep = $(if $(strip $(any-prereq) $(arg-check) ), \
175 @set -e; \
176 $(echo-cmd) $(cmd_$(1)); \
177 scripts/basic/fixdep $(depfile) $@ '$(make-cmd)' > $(dot-target).tmp;\
178 rm -f $(depfile); \
179 mv -f $(dot-target).tmp $(dot-target).cmd)
8ec4b4ff 180
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181# Will check if $(cmd_foo) changed, or any of the prerequisites changed,
182# and if so will execute $(rule_foo).
8ec4b4ff 183# Usage: $(call if_changed_rule,foo)
5de043f4 184#
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185if_changed_rule = $(if $(strip $(any-prereq) $(arg-check) ), \
186 @set -e; \
187 $(rule_$(1)))
188
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189###
190# why - tell why a a target got build
191# enabled by make V=2
192# Output (listed in the order they are checked):
193# (1) - due to target is PHONY
194# (2) - due to target missing
195# (3) - due to: file1.h file2.h
196# (4) - due to command line change
197# (5) - due to missing .cmd file
198# (6) - due to target not in $(targets)
199# (1) PHONY targets are always build
200# (2) No target, so we better build it
201# (3) Prerequisite is newer than target
202# (4) The command line stored in the file named dir/.target.cmd
203# differed from actual command line. This happens when compiler
204# options changes
205# (5) No dir/.target.cmd file (used to store command line)
206# (6) No dir/.target.cmd file and target not listed in $(targets)
207# This is a good hint that there is a bug in the kbuild file
208ifeq ($(KBUILD_VERBOSE),2)
209why = \
210 $(if $(filter $@, $(PHONY)),- due to target is PHONY, \
211 $(if $(wildcard $@), \
212 $(if $(strip $(any-prereq)),- due to: $(any-prereq), \
213 $(if $(arg-check), \
214 $(if $(cmd_$@),- due to command line change, \
215 $(if $(filter $@, $(targets)), \
216 - due to missing .cmd file, \
217 - due to $(notdir $@) not in $$(targets) \
218 ) \
219 ) \
220 ) \
221 ), \
222 - due to target missing \
223 ) \
224 )
225
226echo-why = $(call escsq, $(strip $(why)))
227endif