xref: /openbmc/linux/scripts/Kbuild.include (revision ebd09753)
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# define filechk_sample
45#	echo $KERNELRELEASE
46# endef
47# version.h : Makefile
48#	$(call filechk,sample)
49# The rule defined shall write to stdout the content of the new file.
50# The existing file will be compared with the new one.
51# - If no file exist it is created
52# - If the content differ the new file is used
53# - If they are equal no change, and no timestamp update
54# - stdin is piped in from the first prerequisite ($<) 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.)
118# In addition, do not include the asm macros which are built later.
119CC_OPTION_FILTERED = $(GCC_PLUGINS_CFLAGS) $(ASM_MACRO_FLAGS)
120CC_OPTION_CFLAGS = $(filter-out $(CC_OPTION_FILTERED),$(KBUILD_CFLAGS))
121
122# cc-option
123# Usage: cflags-y += $(call cc-option,-march=winchip-c6,-march=i586)
124
125cc-option = $(call __cc-option, $(CC),\
126	$(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS),$(1),$(2))
127
128# hostcc-option
129# Usage: cflags-y += $(call hostcc-option,-march=winchip-c6,-march=i586)
130hostcc-option = $(call __cc-option, $(HOSTCC),\
131	$(KBUILD_HOSTCFLAGS) $(HOST_EXTRACFLAGS),$(1),$(2))
132
133# cc-option-yn
134# Usage: flag := $(call cc-option-yn,-march=winchip-c6)
135cc-option-yn = $(call try-run,\
136	$(CC) -Werror $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",y,n)
137
138# cc-disable-warning
139# Usage: cflags-y += $(call cc-disable-warning,unused-but-set-variable)
140cc-disable-warning = $(call try-run,\
141	$(CC) -Werror $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1)))
142
143# cc-version
144cc-version = $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-version.sh $(CC))
145
146# cc-ifversion
147# Usage:  EXTRA_CFLAGS += $(call cc-ifversion, -lt, 0402, -O1)
148cc-ifversion = $(shell [ $(cc-version) $(1) $(2) ] && echo $(3) || echo $(4))
149
150# cc-ldoption
151# Usage: ldflags += $(call cc-ldoption, -Wl$(comma)--hash-style=both)
152cc-ldoption = $(call try-run,\
153	$(CC) $(1) $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) -nostdlib -x c /dev/null -o "$$TMP",$(1),$(2))
154
155# ld-option
156# Usage: KBUILD_LDFLAGS += $(call ld-option, -X, -Y)
157ld-option = $(call try-run, $(LD) $(KBUILD_LDFLAGS) $(1) -v,$(1),$(2),$(3))
158
159# ar-option
160# Usage: KBUILD_ARFLAGS := $(call ar-option,D)
161# Important: no spaces around options
162ar-option = $(call try-run, $(AR) rc$(1) "$$TMP",$(1),$(2))
163
164# ld-version
165# Note this is mainly for HJ Lu's 3 number binutil versions
166ld-version = $(shell $(LD) --version | $(srctree)/scripts/ld-version.sh)
167
168# ld-ifversion
169# Usage:  $(call ld-ifversion, -ge, 22252, y)
170ld-ifversion = $(shell [ $(ld-version) $(1) $(2) ] && echo $(3) || echo $(4))
171
172######
173
174###
175# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj=
176# Usage:
177# $(Q)$(MAKE) $(build)=dir
178build := -f $(srctree)/scripts/Makefile.build obj
179
180###
181# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.modbuiltin obj=
182# Usage:
183# $(Q)$(MAKE) $(modbuiltin)=dir
184modbuiltin := -f $(srctree)/scripts/Makefile.modbuiltin obj
185
186###
187# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.dtbinst obj=
188# Usage:
189# $(Q)$(MAKE) $(dtbinst)=dir
190dtbinst := -f $(srctree)/scripts/Makefile.dtbinst obj
191
192###
193# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.clean obj=
194# Usage:
195# $(Q)$(MAKE) $(clean)=dir
196clean := -f $(srctree)/scripts/Makefile.clean obj
197
198###
199# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.headersinst obj=
200# Usage:
201# $(Q)$(MAKE) $(hdr-inst)=dir
202hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
203
204# Prefix -I with $(srctree) if it is not an absolute path.
205# skip if -I has no parameter
206addtree = $(if $(patsubst -I%,%,$(1)), \
207$(if $(filter-out -I/% -I./% -I../%,$(1)),$(patsubst -I%,-I$(srctree)/%,$(1)),$(1)),$(1))
208
209# Find all -I options and call addtree
210flags = $(foreach o,$($(1)),$(if $(filter -I%,$(o)),$(call addtree,$(o)),$(o)))
211
212# echo command.
213# Short version is used, if $(quiet) equals `quiet_', otherwise full one.
214echo-cmd = $(if $($(quiet)cmd_$(1)),\
215	echo '  $(call escsq,$($(quiet)cmd_$(1)))$(echo-why)';)
216
217# printing commands
218cmd = @$(echo-cmd) $(cmd_$(1))
219
220# Add $(obj)/ for paths that are not absolute
221objectify = $(foreach o,$(1),$(if $(filter /%,$(o)),$(o),$(obj)/$(o)))
222
223###
224# if_changed      - execute command if any prerequisite is newer than
225#                   target, or command line has changed
226# if_changed_dep  - as if_changed, but uses fixdep to reveal dependencies
227#                   including used config symbols
228# if_changed_rule - as if_changed but execute rule instead
229# See Documentation/kbuild/makefiles.txt for more info
230
231ifneq ($(KBUILD_NOCMDDEP),1)
232# Check if both arguments are the same including their order. Result is empty
233# string if equal. User may override this check using make KBUILD_NOCMDDEP=1
234arg-check = $(filter-out $(subst $(space),$(space_escape),$(strip $(cmd_$@))), \
235                         $(subst $(space),$(space_escape),$(strip $(cmd_$1))))
236else
237arg-check = $(if $(strip $(cmd_$@)),,1)
238endif
239
240# Replace >$< with >$$< to preserve $ when reloading the .cmd file
241# (needed for make)
242# Replace >#< with >$(pound)< to avoid starting a comment in the .cmd file
243# (needed for make)
244# Replace >'< with >'\''< to be able to enclose the whole string in '...'
245# (needed for the shell)
246make-cmd = $(call escsq,$(subst $(pound),$$(pound),$(subst $$,$$$$,$(cmd_$(1)))))
247
248# Find any prerequisites that is newer than target or that does not exist.
249# PHONY targets skipped in both cases.
250any-prereq = $(filter-out $(PHONY),$?) $(filter-out $(PHONY) $(wildcard $^),$^)
251
252# Execute command if command has changed or prerequisite(s) are updated.
253if_changed = $(if $(strip $(any-prereq) $(arg-check)),                       \
254	@set -e;                                                             \
255	$(echo-cmd) $(cmd_$(1));                                             \
256	printf '%s\n' 'cmd_$@ := $(make-cmd)' > $(dot-target).cmd, @:)
257
258# Execute the command and also postprocess generated .d dependencies file.
259if_changed_dep = $(if $(strip $(any-prereq) $(arg-check) ),                  \
260	@set -e;                                                             \
261	$(cmd_and_fixdep), @:)
262
263ifndef CONFIG_TRIM_UNUSED_KSYMS
264
265cmd_and_fixdep =                                                             \
266	$(echo-cmd) $(cmd_$(1));                                             \
267	scripts/basic/fixdep $(depfile) $@ '$(make-cmd)' > $(dot-target).tmp;\
268	rm -f $(depfile);                                                    \
269	mv -f $(dot-target).tmp $(dot-target).cmd;
270
271else
272
273# Filter out exported kernel symbol names from the preprocessor output.
274# See also __KSYM_DEPS__ in include/linux/export.h.
275# We disable the depfile generation here, so as not to overwrite the existing
276# depfile while fixdep is parsing it.
277flags_nodeps = $(filter-out -Wp$(comma)-M%, $($(1)))
278ksym_dep_filter =                                                            \
279	case "$(1)" in                                                       \
280	  cc_*_c|cpp_i_c)                                                    \
281	    $(CPP) $(call flags_nodeps,c_flags) -D__KSYM_DEPS__ $< ;;        \
282	  as_*_S|cpp_s_S)                                                    \
283	    $(CPP) $(call flags_nodeps,a_flags) -D__KSYM_DEPS__ $< ;;        \
284	  boot*|build*|cpp_its_S|*cpp_lds_S|dtc|host*|vdso*) : ;;            \
285	  *) echo "Don't know how to preprocess $(1)" >&2; false ;;          \
286	esac | tr ";" "\n" | sed -n 's/^.*=== __KSYM_\(.*\) ===.*$$/_\1/p'
287
288cmd_and_fixdep =                                                             \
289	$(echo-cmd) $(cmd_$(1));                                             \
290	$(ksym_dep_filter) |                                                 \
291		scripts/basic/fixdep -e $(depfile) $@ '$(make-cmd)'          \
292			> $(dot-target).tmp;	                             \
293	rm -f $(depfile);                                                    \
294	mv -f $(dot-target).tmp $(dot-target).cmd;
295
296endif
297
298# Usage: $(call if_changed_rule,foo)
299# Will check if $(cmd_foo) or any of the prerequisites changed,
300# and if so will execute $(rule_foo).
301if_changed_rule = $(if $(strip $(any-prereq) $(arg-check) ),                 \
302	@set -e;                                                             \
303	$(rule_$(1)), @:)
304
305###
306# why - tell why a target got built
307#       enabled by make V=2
308#       Output (listed in the order they are checked):
309#          (1) - due to target is PHONY
310#          (2) - due to target missing
311#          (3) - due to: file1.h file2.h
312#          (4) - due to command line change
313#          (5) - due to missing .cmd file
314#          (6) - due to target not in $(targets)
315# (1) PHONY targets are always build
316# (2) No target, so we better build it
317# (3) Prerequisite is newer than target
318# (4) The command line stored in the file named dir/.target.cmd
319#     differed from actual command line. This happens when compiler
320#     options changes
321# (5) No dir/.target.cmd file (used to store command line)
322# (6) No dir/.target.cmd file and target not listed in $(targets)
323#     This is a good hint that there is a bug in the kbuild file
324ifeq ($(KBUILD_VERBOSE),2)
325why =                                                                        \
326    $(if $(filter $@, $(PHONY)),- due to target is PHONY,                    \
327        $(if $(wildcard $@),                                                 \
328            $(if $(strip $(any-prereq)),- due to: $(any-prereq),             \
329                $(if $(arg-check),                                           \
330                    $(if $(cmd_$@),- due to command line change,             \
331                        $(if $(filter $@, $(targets)),                       \
332                            - due to missing .cmd file,                      \
333                            - due to $(notdir $@) not in $$(targets)         \
334                         )                                                   \
335                     )                                                       \
336                 )                                                           \
337             ),                                                              \
338             - due to target missing                                         \
339         )                                                                   \
340     )
341
342echo-why = $(call escsq, $(strip $(why)))
343endif
344
345###############################################################################
346#
347# When a Kconfig string contains a filename, it is suitable for
348# passing to shell commands. It is surrounded by double-quotes, and
349# any double-quotes or backslashes within it are escaped by
350# backslashes.
351#
352# This is no use for dependencies or $(wildcard). We need to strip the
353# surrounding quotes and the escaping from quotes and backslashes, and
354# we *do* need to escape any spaces in the string. So, for example:
355#
356# Usage: $(eval $(call config_filename,FOO))
357#
358# Defines FOO_FILENAME based on the contents of the CONFIG_FOO option,
359# transformed as described above to be suitable for use within the
360# makefile.
361#
362# Also, if the filename is a relative filename and exists in the source
363# tree but not the build tree, define FOO_SRCPREFIX as $(srctree)/ to
364# be prefixed to *both* command invocation and dependencies.
365#
366# Note: We also print the filenames in the quiet_cmd_foo text, and
367# perhaps ought to have a version specially escaped for that purpose.
368# But it's only cosmetic, and $(patsubst "%",%,$(CONFIG_FOO)) is good
369# enough.  It'll strip the quotes in the common case where there's no
370# space and it's a simple filename, and it'll retain the quotes when
371# there's a space. There are some esoteric cases in which it'll print
372# the wrong thing, but we don't really care. The actual dependencies
373# and commands *do* get it right, with various combinations of single
374# and double quotes, backslashes and spaces in the filenames.
375#
376###############################################################################
377#
378define config_filename
379ifneq ($$(CONFIG_$(1)),"")
380$(1)_FILENAME := $$(subst \\,\,$$(subst \$$(quote),$$(quote),$$(subst $$(space_escape),\$$(space),$$(patsubst "%",%,$$(subst $$(space),$$(space_escape),$$(CONFIG_$(1)))))))
381ifneq ($$(patsubst /%,%,$$(firstword $$($(1)_FILENAME))),$$(firstword $$($(1)_FILENAME)))
382else
383ifeq ($$(wildcard $$($(1)_FILENAME)),)
384ifneq ($$(wildcard $$(srctree)/$$($(1)_FILENAME)),)
385$(1)_SRCPREFIX := $(srctree)/
386endif
387endif
388endif
389endif
390endef
391#
392###############################################################################
393
394# delete partially updated (i.e. corrupted) files on error
395.DELETE_ON_ERROR:
396