Kbuild.include 13.2 KB
Newer Older
1 2 3
####
# kbuild: Generic definitions

4
# Convenient variables
5
comma   := ,
6
quote   := "
7
squote  := '
8 9
empty   :=
space   := $(empty) $(empty)
10
space_escape := _-_SPACE_-_
11
pound := \#
12

13 14 15 16
###
# Name of target with a '.' as filename prefix. foo/bar.o => foo/.bar.o
dot-target = $(dir $@).$(notdir $@)

17 18 19
###
# The temporary file to save gcc -MD generated dependencies must not
# contain a comma
20
depfile = $(subst $(comma),_,$(dot-target).d)
21

22 23 24 25
###
# filename of target with directory and extension stripped
basetarget = $(basename $(notdir $@))

26 27 28 29
###
# real prerequisites without phony targets
real-prereqs = $(filter-out $(PHONY), $^)

30 31 32 33
###
# Escape single quote for use in echo statements
escsq = $(subst $(squote),'\$(squote)',$1)

34 35 36 37 38 39 40
###
# Easy method for doing a status message
       kecho := :
 quiet_kecho := echo
silent_kecho := :
kecho := $($(quiet)kecho)

41 42 43
###
# filechk is used to check if the content of a generated file is updated.
# Sample usage:
44 45 46
#
# filechk_sample = echo $(KERNELRELEASE)
# version.h: FORCE
47
#	$(call filechk,sample)
48
#
49 50 51 52 53 54 55 56 57 58
# The rule defined shall write to stdout the content of the new file.
# The existing file will be compared with the new one.
# - If no file exist it is created
# - If the content differ the new file is used
# - If they are equal no change, and no timestamp update
# - stdin is piped in from the first prerequisite ($<) so one has
#   to specify a valid file as first prerequisite (often the kbuild file)
define filechk
	$(Q)set -e;				\
	mkdir -p $(dir $@);			\
59
	{ $(filechk_$(1)); } > $@.tmp;		\
60 61 62
	if [ -r $@ ] && cmp -s $@ $@.tmp; then	\
		rm -f $@.tmp;			\
	else					\
63
		$(kecho) '  UPD     $@';	\
64 65 66 67
		mv -f $@.tmp $@;		\
	fi
endef

68
######
69
# gcc support functions
70 71
# See documentation in Documentation/kbuild/makefiles.txt

72 73
# cc-cross-prefix
# Usage: CROSS_COMPILE := $(call cc-cross-prefix, m68k-linux-gnu- m68k-linux-)
74 75
# Return first <prefix> where a <prefix>gcc is found in PATH.
# If no gcc found in PATH with listed prefixes return nothing
76 77 78 79 80
#
# 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.
81
cc-cross-prefix = $(firstword $(foreach c, $(filter-out -%, $(1)), \
82
			$(if $(shell command -v $(c)gcc 2>/dev/null), $(c))))
83

84 85 86 87 88
# output directory for tests below
TMPOUT := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/)

# try-run
# Usage: option = $(call try-run, $(CC)...-o "$$TMP",option-ok,otherwise)
89 90
# Exit code chooses option. "$$TMP" serves as a temporary file and is
# automatically cleaned up.
91
try-run = $(shell set -e;		\
92
	TMP="$(TMPOUT).$$$$.tmp";	\
Sam Ravnborg's avatar
Sam Ravnborg committed
93
	TMPO="$(TMPOUT).$$$$.o";	\
94 95 96 97
	if ($(1)) >/dev/null 2>&1;	\
	then echo "$(2)";		\
	else echo "$(3)";		\
	fi;				\
98
	rm -f "$$TMP" "$$TMPO")
99

100
# as-option
101
# Usage: cflags-y += $(call as-option,-Wa$(comma)-isa=foo,)
102

103
as-option = $(call try-run,\
Jean Delvare's avatar
Jean Delvare committed
104
	$(CC) $(KBUILD_CFLAGS) $(1) -c -x assembler /dev/null -o "$$TMP",$(1),$(2))
105

106
# as-instr
107
# Usage: cflags-y += $(call as-instr,instr,option1,option2)
108

109
as-instr = $(call try-run,\
Jean Delvare's avatar
Jean Delvare committed
110
	printf "%b\n" "$(1)" | $(CC) $(KBUILD_AFLAGS) -c -x assembler -o "$$TMP" -,$(2),$(3))
111

112 113
# __cc-option
# Usage: MY_CFLAGS += $(call __cc-option,$(CC),$(MY_CFLAGS),-march=winchip-c6,-march=i586)
114
__cc-option = $(call try-run,\
115 116
	$(1) -Werror $(2) $(3) -c -x c /dev/null -o "$$TMP",$(3),$(4))

117 118
# Do not attempt to build with gcc plugins during cc-option tests.
# (And this uses delayed resolution so the flags will be up to date.)
119
CC_OPTION_CFLAGS = $(filter-out $(GCC_PLUGINS_CFLAGS),$(KBUILD_CFLAGS))
120

121
# cc-option
122
# Usage: cflags-y += $(call cc-option,-march=winchip-c6,-march=i586)
123

124 125 126 127 128 129
cc-option = $(call __cc-option, $(CC),\
	$(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS),$(1),$(2))

# hostcc-option
# Usage: cflags-y += $(call hostcc-option,-march=winchip-c6,-march=i586)
hostcc-option = $(call __cc-option, $(HOSTCC),\
130
	$(KBUILD_HOSTCFLAGS) $(HOST_EXTRACFLAGS),$(1),$(2))
131 132

# cc-option-yn
133
# Usage: flag := $(call cc-option-yn,-march=winchip-c6)
134
cc-option-yn = $(call try-run,\
135
	$(CC) -Werror $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",y,n)
136

137 138
# cc-disable-warning
# Usage: cflags-y += $(call cc-disable-warning,unused-but-set-variable)
139
cc-disable-warning = $(call try-run,\
140
	$(CC) -Werror $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1)))
141

142 143
# cc-ifversion
# Usage:  EXTRA_CFLAGS += $(call cc-ifversion, -lt, 0402, -O1)
144
cc-ifversion = $(shell [ $(CONFIG_GCC_VERSION)0 $(1) $(2)000 ] && echo $(3) || echo $(4))
145

146 147
# cc-ldoption
# Usage: ldflags += $(call cc-ldoption, -Wl$(comma)--hash-style=both)
148
cc-ldoption = $(call try-run,\
149
	$(CC) $(1) $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) -nostdlib -x c /dev/null -o "$$TMP",$(1),$(2))
150

Sam Ravnborg's avatar
Sam Ravnborg committed
151
# ld-option
152 153
# Usage: KBUILD_LDFLAGS += $(call ld-option, -X, -Y)
ld-option = $(call try-run, $(LD) $(KBUILD_LDFLAGS) $(1) -v,$(1),$(2),$(3))
Sam Ravnborg's avatar
Sam Ravnborg committed
154

155 156 157
# ar-option
# Usage: KBUILD_ARFLAGS := $(call ar-option,D)
# Important: no spaces around options
158
ar-option = $(call try-run, $(AR) rc$(1) "$$TMP",$(1),$(2))
159

160 161
# ld-version
# Note this is mainly for HJ Lu's 3 number binutil versions
162
ld-version = $(shell $(LD) --version | $(srctree)/scripts/ld-version.sh)
163 164 165

# ld-ifversion
# Usage:  $(call ld-ifversion, -ge, 22252, y)
166
ld-ifversion = $(shell [ $(ld-version) $(1) $(2) ] && echo $(3) || echo $(4))
167

168
######
Roland McGrath's avatar
Roland McGrath committed
169

170
###
171 172 173
# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj=
# Usage:
# $(Q)$(MAKE) $(build)=dir
174
build := -f $(srctree)/scripts/Makefile.build obj
175

176 177 178 179
###
# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.modbuiltin obj=
# Usage:
# $(Q)$(MAKE) $(modbuiltin)=dir
180
modbuiltin := -f $(srctree)/scripts/Makefile.modbuiltin obj
181

182 183 184 185
###
# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.dtbinst obj=
# Usage:
# $(Q)$(MAKE) $(dtbinst)=dir
186
dtbinst := -f $(srctree)/scripts/Makefile.dtbinst obj
187

188 189 190 191 192 193 194
###
# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.clean obj=
# Usage:
# $(Q)$(MAKE) $(clean)=dir
clean := -f $(srctree)/scripts/Makefile.clean obj

###
195
# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.headersinst obj=
196 197
# Usage:
# $(Q)$(MAKE) $(hdr-inst)=dir
198
hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
199

200
# Prefix -I with $(srctree) if it is not an absolute path.
201 202
# skip if -I has no parameter
addtree = $(if $(patsubst -I%,%,$(1)), \
203
$(if $(filter-out -I/% -I./% -I../%,$(1)),$(patsubst -I%,-I$(srctree)/%,$(1)),$(1)),$(1))
204

205
# Find all -I options and call addtree
206
flags = $(foreach o,$($(1)),$(if $(filter -I%,$(o)),$(call addtree,$(o)),$(o)))
207

208 209
# echo command.
# Short version is used, if $(quiet) equals `quiet_', otherwise full one.
210
echo-cmd = $(if $($(quiet)cmd_$(1)),\
211 212 213
	echo '  $(call escsq,$($(quiet)cmd_$(1)))$(echo-why)';)

# printing commands
214
cmd = @set -e; $(echo-cmd) $(cmd_$(1))
215

216
# Add $(obj)/ for paths that are not absolute
217
objectify = $(foreach o,$(1),$(if $(filter /%,$(o)),$(o),$(obj)/$(o)))
Sam Ravnborg's avatar
Sam Ravnborg committed
218

219
###
220
# if_changed      - execute command if any prerequisite is newer than
221 222 223 224 225 226 227
#                   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)
228 229 230 231
# Check if both arguments 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 $(cmd_$@))), \
                         $(subst $(space),$(space_escape),$(strip $(cmd_$1))))
232 233
else
arg-check = $(if $(strip $(cmd_$@)),,1)
234 235
endif

236 237
# Replace >$< with >$$< to preserve $ when reloading the .cmd file
# (needed for make)
238
# Replace >#< with >$(pound)< to avoid starting a comment in the .cmd file
239 240 241
# (needed for make)
# Replace >'< with >'\''< to be able to enclose the whole string in '...'
# (needed for the shell)
242
make-cmd = $(call escsq,$(subst $(pound),$$(pound),$(subst $$,$$$$,$(cmd_$(1)))))
243

244 245 246 247
# 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 $^),$^)

248
# Execute command if command has changed or prerequisite(s) are updated.
249
if_changed = $(if $(strip $(any-prereq) $(arg-check)),                       \
250
	$(cmd);                                                              \
251
	printf '%s\n' 'cmd_$@ := $(make-cmd)' > $(dot-target).cmd, @:)
252

253
# Execute the command and also postprocess generated .d dependencies file.
254
if_changed_dep = $(if $(strip $(any-prereq) $(arg-check)),$(cmd_and_fixdep),@:)
255

256
cmd_and_fixdep =                                                             \
257
	$(cmd);                                                              \
258
	scripts/basic/fixdep $(depfile) $@ '$(make-cmd)' > $(dot-target).cmd;\
259
	rm -f $(depfile)
260

261
# Usage: $(call if_changed_rule,foo)
262 263
# Will check if $(cmd_foo) or any of the prerequisites changed,
# and if so will execute $(rule_foo).
264
if_changed_rule = $(if $(strip $(any-prereq) $(arg-check)),$(rule_$(1)),@:)
265

266
###
267
# why - tell why a target got built
268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304
#       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
305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353

###############################################################################
#
# When a Kconfig string contains a filename, it is suitable for
# passing to shell commands. It is surrounded by double-quotes, and
# any double-quotes or backslashes within it are escaped by
# backslashes.
#
# This is no use for dependencies or $(wildcard). We need to strip the
# surrounding quotes and the escaping from quotes and backslashes, and
# we *do* need to escape any spaces in the string. So, for example:
#
# Usage: $(eval $(call config_filename,FOO))
#
# Defines FOO_FILENAME based on the contents of the CONFIG_FOO option,
# transformed as described above to be suitable for use within the
# makefile.
#
# Also, if the filename is a relative filename and exists in the source
# tree but not the build tree, define FOO_SRCPREFIX as $(srctree)/ to
# be prefixed to *both* command invocation and dependencies.
#
# Note: We also print the filenames in the quiet_cmd_foo text, and
# perhaps ought to have a version specially escaped for that purpose.
# But it's only cosmetic, and $(patsubst "%",%,$(CONFIG_FOO)) is good
# enough.  It'll strip the quotes in the common case where there's no
# space and it's a simple filename, and it'll retain the quotes when
# there's a space. There are some esoteric cases in which it'll print
# the wrong thing, but we don't really care. The actual dependencies
# and commands *do* get it right, with various combinations of single
# and double quotes, backslashes and spaces in the filenames.
#
###############################################################################
#
define config_filename
ifneq ($$(CONFIG_$(1)),"")
$(1)_FILENAME := $$(subst \\,\,$$(subst \$$(quote),$$(quote),$$(subst $$(space_escape),\$$(space),$$(patsubst "%",%,$$(subst $$(space),$$(space_escape),$$(CONFIG_$(1)))))))
ifneq ($$(patsubst /%,%,$$(firstword $$($(1)_FILENAME))),$$(firstword $$($(1)_FILENAME)))
else
ifeq ($$(wildcard $$($(1)_FILENAME)),)
ifneq ($$(wildcard $$(srctree)/$$($(1)_FILENAME)),)
$(1)_SRCPREFIX := $(srctree)/
endif
endif
endif
endif
endef
#
###############################################################################
354 355 356

# delete partially updated (i.e. corrupted) files on error
.DELETE_ON_ERROR:
357 358 359

# do not delete intermediate files automatically
.SECONDARY: