xref: /openbmc/linux/scripts/Kbuild.include (revision d0e22329)
1####
2# kbuild: Generic definitions
3
4# Convenient variables
5comma   := ,
6quote   := "
7squote  := '
8empty   :=
9space   := $(empty) $(empty)
10space_escape := _-_SPACE_-_
11pound := \#
12
13###
14# Name of target with a '.' as filename prefix. foo/bar.o => foo/.bar.o
15dot-target = $(dir $@).$(notdir $@)
16
17###
18# The temporary file to save gcc -MD generated dependencies must not
19# contain a comma
20depfile = $(subst $(comma),_,$(dot-target).d)
21
22###
23# filename of target with directory and extension stripped
24basetarget = $(basename $(notdir $@))
25
26###
27# filename of first prerequisite with directory and extension stripped
28baseprereq = $(basename $(notdir $<))
29
30###
31# Escape single quote for use in echo statements
32escsq = $(subst $(squote),'\$(squote)',$1)
33
34###
35# Easy method for doing a status message
36       kecho := :
37 quiet_kecho := echo
38silent_kecho := :
39kecho := $($(quiet)kecho)
40
41###
42# filechk is used to check if the content of a generated file is updated.
43# Sample usage:
44#
45# filechk_sample = echo $(KERNELRELEASE)
46# version.h: FORCE
47#	$(call filechk,sample)
48#
49# The rule defined shall write to stdout the content of the new file.
50# The existing file will be compared with the new one.
51# - If no file exist it is created
52# - If the content differ the new file is used
53# - If they are equal no change, and no timestamp update
54# - stdin is piped in from the first prerequisite ($<) so one has
55#   to specify a valid file as first prerequisite (often the kbuild file)
56define filechk
57	$(Q)set -e;				\
58	mkdir -p $(dir $@);			\
59	{ $(filechk_$(1)); } > $@.tmp;		\
60	if [ -r $@ ] && cmp -s $@ $@.tmp; then	\
61		rm -f $@.tmp;			\
62	else					\
63		$(kecho) '  UPD     $@';	\
64		mv -f $@.tmp $@;		\
65	fi
66endef
67
68######
69# gcc support functions
70# See documentation in Documentation/kbuild/makefiles.txt
71
72# cc-cross-prefix
73# Usage: CROSS_COMPILE := $(call cc-cross-prefix, m68k-linux-gnu- m68k-linux-)
74# Return first prefix where a prefix$(CC) is found in PATH.
75# If no $(CC) found in PATH with listed prefixes return nothing
76cc-cross-prefix =  \
77	$(word 1, $(foreach c,$(1),                                   \
78		$(shell set -e;                                       \
79		if (which $(strip $(c))$(CC)) > /dev/null 2>&1 ; then \
80			echo $(c);                                    \
81		fi)))
82
83# output directory for tests below
84TMPOUT := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/)
85
86# try-run
87# Usage: option = $(call try-run, $(CC)...-o "$$TMP",option-ok,otherwise)
88# Exit code chooses option. "$$TMP" serves as a temporary file and is
89# automatically cleaned up.
90try-run = $(shell set -e;		\
91	TMP="$(TMPOUT).$$$$.tmp";	\
92	TMPO="$(TMPOUT).$$$$.o";	\
93	if ($(1)) >/dev/null 2>&1;	\
94	then echo "$(2)";		\
95	else echo "$(3)";		\
96	fi;				\
97	rm -f "$$TMP" "$$TMPO")
98
99# as-option
100# Usage: cflags-y += $(call as-option,-Wa$(comma)-isa=foo,)
101
102as-option = $(call try-run,\
103	$(CC) $(KBUILD_CFLAGS) $(1) -c -x assembler /dev/null -o "$$TMP",$(1),$(2))
104
105# as-instr
106# Usage: cflags-y += $(call as-instr,instr,option1,option2)
107
108as-instr = $(call try-run,\
109	printf "%b\n" "$(1)" | $(CC) $(KBUILD_AFLAGS) -c -x assembler -o "$$TMP" -,$(2),$(3))
110
111# __cc-option
112# Usage: MY_CFLAGS += $(call __cc-option,$(CC),$(MY_CFLAGS),-march=winchip-c6,-march=i586)
113__cc-option = $(call try-run,\
114	$(1) -Werror $(2) $(3) -c -x c /dev/null -o "$$TMP",$(3),$(4))
115
116# Do not attempt to build with gcc plugins during cc-option tests.
117# (And this uses delayed resolution so the flags will be up to date.)
118CC_OPTION_CFLAGS = $(filter-out $(GCC_PLUGINS_CFLAGS),$(KBUILD_CFLAGS))
119
120# cc-option
121# Usage: cflags-y += $(call cc-option,-march=winchip-c6,-march=i586)
122
123cc-option = $(call __cc-option, $(CC),\
124	$(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS),$(1),$(2))
125
126# hostcc-option
127# Usage: cflags-y += $(call hostcc-option,-march=winchip-c6,-march=i586)
128hostcc-option = $(call __cc-option, $(HOSTCC),\
129	$(KBUILD_HOSTCFLAGS) $(HOST_EXTRACFLAGS),$(1),$(2))
130
131# cc-option-yn
132# Usage: flag := $(call cc-option-yn,-march=winchip-c6)
133cc-option-yn = $(call try-run,\
134	$(CC) -Werror $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",y,n)
135
136# cc-disable-warning
137# Usage: cflags-y += $(call cc-disable-warning,unused-but-set-variable)
138cc-disable-warning = $(call try-run,\
139	$(CC) -Werror $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1)))
140
141# cc-version
142cc-version = $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-version.sh $(CC))
143
144# cc-ifversion
145# Usage:  EXTRA_CFLAGS += $(call cc-ifversion, -lt, 0402, -O1)
146cc-ifversion = $(shell [ $(cc-version) $(1) $(2) ] && echo $(3) || echo $(4))
147
148# cc-ldoption
149# Usage: ldflags += $(call cc-ldoption, -Wl$(comma)--hash-style=both)
150cc-ldoption = $(call try-run,\
151	$(CC) $(1) $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) -nostdlib -x c /dev/null -o "$$TMP",$(1),$(2))
152
153# ld-option
154# Usage: KBUILD_LDFLAGS += $(call ld-option, -X, -Y)
155ld-option = $(call try-run, $(LD) $(KBUILD_LDFLAGS) $(1) -v,$(1),$(2),$(3))
156
157# ar-option
158# Usage: KBUILD_ARFLAGS := $(call ar-option,D)
159# Important: no spaces around options
160ar-option = $(call try-run, $(AR) rc$(1) "$$TMP",$(1),$(2))
161
162# ld-version
163# Note this is mainly for HJ Lu's 3 number binutil versions
164ld-version = $(shell $(LD) --version | $(srctree)/scripts/ld-version.sh)
165
166# ld-ifversion
167# Usage:  $(call ld-ifversion, -ge, 22252, y)
168ld-ifversion = $(shell [ $(ld-version) $(1) $(2) ] && echo $(3) || echo $(4))
169
170######
171
172###
173# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj=
174# Usage:
175# $(Q)$(MAKE) $(build)=dir
176build := -f $(srctree)/scripts/Makefile.build obj
177
178###
179# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.modbuiltin obj=
180# Usage:
181# $(Q)$(MAKE) $(modbuiltin)=dir
182modbuiltin := -f $(srctree)/scripts/Makefile.modbuiltin obj
183
184###
185# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.dtbinst obj=
186# Usage:
187# $(Q)$(MAKE) $(dtbinst)=dir
188dtbinst := -f $(srctree)/scripts/Makefile.dtbinst obj
189
190###
191# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.clean obj=
192# Usage:
193# $(Q)$(MAKE) $(clean)=dir
194clean := -f $(srctree)/scripts/Makefile.clean obj
195
196###
197# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.headersinst obj=
198# Usage:
199# $(Q)$(MAKE) $(hdr-inst)=dir
200hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
201
202# Prefix -I with $(srctree) if it is not an absolute path.
203# skip if -I has no parameter
204addtree = $(if $(patsubst -I%,%,$(1)), \
205$(if $(filter-out -I/% -I./% -I../%,$(1)),$(patsubst -I%,-I$(srctree)/%,$(1)),$(1)),$(1))
206
207# Find all -I options and call addtree
208flags = $(foreach o,$($(1)),$(if $(filter -I%,$(o)),$(call addtree,$(o)),$(o)))
209
210# echo command.
211# Short version is used, if $(quiet) equals `quiet_', otherwise full one.
212echo-cmd = $(if $($(quiet)cmd_$(1)),\
213	echo '  $(call escsq,$($(quiet)cmd_$(1)))$(echo-why)';)
214
215# printing commands
216cmd = @set -e; $(echo-cmd) $(cmd_$(1))
217
218# Add $(obj)/ for paths that are not absolute
219objectify = $(foreach o,$(1),$(if $(filter /%,$(o)),$(o),$(obj)/$(o)))
220
221###
222# if_changed      - execute command if any prerequisite is newer than
223#                   target, or command line has changed
224# if_changed_dep  - as if_changed, but uses fixdep to reveal dependencies
225#                   including used config symbols
226# if_changed_rule - as if_changed but execute rule instead
227# See Documentation/kbuild/makefiles.txt for more info
228
229ifneq ($(KBUILD_NOCMDDEP),1)
230# Check if both arguments are the same including their order. Result is empty
231# string if equal. User may override this check using make KBUILD_NOCMDDEP=1
232arg-check = $(filter-out $(subst $(space),$(space_escape),$(strip $(cmd_$@))), \
233                         $(subst $(space),$(space_escape),$(strip $(cmd_$1))))
234else
235arg-check = $(if $(strip $(cmd_$@)),,1)
236endif
237
238# Replace >$< with >$$< to preserve $ when reloading the .cmd file
239# (needed for make)
240# Replace >#< with >$(pound)< to avoid starting a comment in the .cmd file
241# (needed for make)
242# Replace >'< with >'\''< to be able to enclose the whole string in '...'
243# (needed for the shell)
244make-cmd = $(call escsq,$(subst $(pound),$$(pound),$(subst $$,$$$$,$(cmd_$(1)))))
245
246# Find any prerequisites that is newer than target or that does not exist.
247# PHONY targets skipped in both cases.
248any-prereq = $(filter-out $(PHONY),$?) $(filter-out $(PHONY) $(wildcard $^),$^)
249
250# Execute command if command has changed or prerequisite(s) are updated.
251if_changed = $(if $(strip $(any-prereq) $(arg-check)),                       \
252	$(cmd);                                                              \
253	printf '%s\n' 'cmd_$@ := $(make-cmd)' > $(dot-target).cmd, @:)
254
255# Execute the command and also postprocess generated .d dependencies file.
256if_changed_dep = $(if $(strip $(any-prereq) $(arg-check)),$(cmd_and_fixdep),@:)
257
258cmd_and_fixdep =                                                             \
259	$(cmd);                                                              \
260	scripts/basic/fixdep $(depfile) $@ '$(make-cmd)' > $(dot-target).cmd;\
261	rm -f $(depfile)
262
263# Usage: $(call if_changed_rule,foo)
264# Will check if $(cmd_foo) or any of the prerequisites changed,
265# and if so will execute $(rule_foo).
266if_changed_rule = $(if $(strip $(any-prereq) $(arg-check)),$(rule_$(1)),@:)
267
268###
269# why - tell why a target got built
270#       enabled by make V=2
271#       Output (listed in the order they are checked):
272#          (1) - due to target is PHONY
273#          (2) - due to target missing
274#          (3) - due to: file1.h file2.h
275#          (4) - due to command line change
276#          (5) - due to missing .cmd file
277#          (6) - due to target not in $(targets)
278# (1) PHONY targets are always build
279# (2) No target, so we better build it
280# (3) Prerequisite is newer than target
281# (4) The command line stored in the file named dir/.target.cmd
282#     differed from actual command line. This happens when compiler
283#     options changes
284# (5) No dir/.target.cmd file (used to store command line)
285# (6) No dir/.target.cmd file and target not listed in $(targets)
286#     This is a good hint that there is a bug in the kbuild file
287ifeq ($(KBUILD_VERBOSE),2)
288why =                                                                        \
289    $(if $(filter $@, $(PHONY)),- due to target is PHONY,                    \
290        $(if $(wildcard $@),                                                 \
291            $(if $(strip $(any-prereq)),- due to: $(any-prereq),             \
292                $(if $(arg-check),                                           \
293                    $(if $(cmd_$@),- due to command line change,             \
294                        $(if $(filter $@, $(targets)),                       \
295                            - due to missing .cmd file,                      \
296                            - due to $(notdir $@) not in $$(targets)         \
297                         )                                                   \
298                     )                                                       \
299                 )                                                           \
300             ),                                                              \
301             - due to target missing                                         \
302         )                                                                   \
303     )
304
305echo-why = $(call escsq, $(strip $(why)))
306endif
307
308###############################################################################
309#
310# When a Kconfig string contains a filename, it is suitable for
311# passing to shell commands. It is surrounded by double-quotes, and
312# any double-quotes or backslashes within it are escaped by
313# backslashes.
314#
315# This is no use for dependencies or $(wildcard). We need to strip the
316# surrounding quotes and the escaping from quotes and backslashes, and
317# we *do* need to escape any spaces in the string. So, for example:
318#
319# Usage: $(eval $(call config_filename,FOO))
320#
321# Defines FOO_FILENAME based on the contents of the CONFIG_FOO option,
322# transformed as described above to be suitable for use within the
323# makefile.
324#
325# Also, if the filename is a relative filename and exists in the source
326# tree but not the build tree, define FOO_SRCPREFIX as $(srctree)/ to
327# be prefixed to *both* command invocation and dependencies.
328#
329# Note: We also print the filenames in the quiet_cmd_foo text, and
330# perhaps ought to have a version specially escaped for that purpose.
331# But it's only cosmetic, and $(patsubst "%",%,$(CONFIG_FOO)) is good
332# enough.  It'll strip the quotes in the common case where there's no
333# space and it's a simple filename, and it'll retain the quotes when
334# there's a space. There are some esoteric cases in which it'll print
335# the wrong thing, but we don't really care. The actual dependencies
336# and commands *do* get it right, with various combinations of single
337# and double quotes, backslashes and spaces in the filenames.
338#
339###############################################################################
340#
341define config_filename
342ifneq ($$(CONFIG_$(1)),"")
343$(1)_FILENAME := $$(subst \\,\,$$(subst \$$(quote),$$(quote),$$(subst $$(space_escape),\$$(space),$$(patsubst "%",%,$$(subst $$(space),$$(space_escape),$$(CONFIG_$(1)))))))
344ifneq ($$(patsubst /%,%,$$(firstword $$($(1)_FILENAME))),$$(firstword $$($(1)_FILENAME)))
345else
346ifeq ($$(wildcard $$($(1)_FILENAME)),)
347ifneq ($$(wildcard $$(srctree)/$$($(1)_FILENAME)),)
348$(1)_SRCPREFIX := $(srctree)/
349endif
350endif
351endif
352endif
353endef
354#
355###############################################################################
356
357# delete partially updated (i.e. corrupted) files on error
358.DELETE_ON_ERROR:
359
360# do not delete intermediate files automatically
361.SECONDARY:
362