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1# SPDX-License-Identifier: GPL-2.0
2####
3# kbuild: Generic definitions
4
5# Convenient variables
6comma := ,
7quote := "
8squote := '
9empty :=
10space := $(empty) $(empty)
11space_escape := _-_SPACE_-_
12pound := \#
13define newline
14
15
16endef
17
18###
19# Comparison macros.
20# Usage: $(call test-lt, $(CONFIG_LLD_VERSION), 150000)
21#
22# Use $(intcmp ...) if supported. (Make >= 4.4)
23# Otherwise, fall back to the 'test' shell command.
24ifeq ($(intcmp 1,0,,,y),y)
25test-ge = $(intcmp $(strip $1)0, $(strip $2)0,,y,y)
26test-gt = $(intcmp $(strip $1)0, $(strip $2)0,,,y)
27else
28test-ge = $(shell test $(strip $1)0 -ge $(strip $2)0 && echo y)
29test-gt = $(shell test $(strip $1)0 -gt $(strip $2)0 && echo y)
30endif
31test-le = $(call test-ge, $2, $1)
32test-lt = $(call test-gt, $2, $1)
33
34###
35# Name of target with a '.' as filename prefix. foo/bar.o => foo/.bar.o
36dot-target = $(dir $@).$(notdir $@)
37
38###
39# Name of target with a '.tmp_' as filename prefix. foo/bar.o => foo/.tmp_bar.o
40tmp-target = $(dir $@).tmp_$(notdir $@)
41
42###
43# The temporary file to save gcc -MMD generated dependencies must not
44# contain a comma
45depfile = $(subst $(comma),_,$(dot-target).d)
46
47###
48# filename of target with directory and extension stripped
49basetarget = $(basename $(notdir $@))
50
51###
52# real prerequisites without phony targets
53real-prereqs = $(filter-out $(PHONY), $^)
54
55###
56# Escape single quote for use in echo statements
57escsq = $(subst $(squote),'\$(squote)',$1)
58
59###
60# Quote a string to pass it to C files. foo => '"foo"'
61stringify = $(squote)$(quote)$1$(quote)$(squote)
62
63###
64# The path to Kbuild or Makefile. Kbuild has precedence over Makefile.
65kbuild-dir = $(if $(filter /%,$(src)),$(src),$(srctree)/$(src))
66kbuild-file = $(or $(wildcard $(kbuild-dir)/Kbuild),$(kbuild-dir)/Makefile)
67
68###
69# Read a file, replacing newlines with spaces
70#
71# Make 4.2 or later can read a file by using its builtin function.
72ifneq ($(filter-out 3.% 4.0 4.1, $(MAKE_VERSION)),)
73read-file = $(subst $(newline),$(space),$(file < $1))
74else
75read-file = $(shell cat $1 2>/dev/null)
76endif
77
78###
79# Easy method for doing a status message
80 kecho := :
81 quiet_kecho := echo
82silent_kecho := :
83kecho := $($(quiet)kecho)
84
85###
86# filechk is used to check if the content of a generated file is updated.
87# Sample usage:
88#
89# filechk_sample = echo $(KERNELRELEASE)
90# version.h: FORCE
91# $(call filechk,sample)
92#
93# The rule defined shall write to stdout the content of the new file.
94# The existing file will be compared with the new one.
95# - If no file exist it is created
96# - If the content differ the new file is used
97# - If they are equal no change, and no timestamp update
98define filechk
99 $(check-FORCE)
100 $(Q)set -e; \
101 mkdir -p $(dir $@); \
102 trap "rm -f $(dot-target).tmp" EXIT; \
103 { $(filechk_$(1)); } > $(dot-target).tmp; \
104 if [ ! -r $@ ] || ! cmp -s $@ $(dot-target).tmp; then \
105 $(kecho) ' UPD $@'; \
106 mv -f $(dot-target).tmp $@; \
107 fi
108endef
109
110###
111# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj=
112# Usage:
113# $(Q)$(MAKE) $(build)=dir
114build := -f $(srctree)/scripts/Makefile.build obj
115
116###
117# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.dtbinst obj=
118# Usage:
119# $(Q)$(MAKE) $(dtbinst)=dir
120dtbinst := -f $(srctree)/scripts/Makefile.dtbinst obj
121
122###
123# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.clean obj=
124# Usage:
125# $(Q)$(MAKE) $(clean)=dir
126clean := -f $(srctree)/scripts/Makefile.clean obj
127
128# echo command.
129# Short version is used, if $(quiet) equals `quiet_', otherwise full one.
130echo-cmd = $(if $($(quiet)cmd_$(1)),\
131 echo ' $(call escsq,$($(quiet)cmd_$(1)))$(echo-why)';)
132
133# sink stdout for 'make -s'
134 redirect :=
135 quiet_redirect :=
136silent_redirect := exec >/dev/null;
137
138# Delete the target on interruption
139#
140# GNU Make automatically deletes the target if it has already been changed by
141# the interrupted recipe. So, you can safely stop the build by Ctrl-C (Make
142# will delete incomplete targets), and resume it later.
143#
144# However, this does not work when the stderr is piped to another program, like
145# $ make >&2 | tee log
146# Make dies with SIGPIPE before cleaning the targets.
147#
148# To address it, we clean the target in signal traps.
149#
150# Make deletes the target when it catches SIGHUP, SIGINT, SIGQUIT, SIGTERM.
151# So, we cover them, and also SIGPIPE just in case.
152#
153# Of course, this is unneeded for phony targets.
154delete-on-interrupt = \
155 $(if $(filter-out $(PHONY), $@), \
156 $(foreach sig, HUP INT QUIT TERM PIPE, \
157 trap 'rm -f $@; trap - $(sig); kill -s $(sig) $$$$' $(sig);))
158
159# printing commands
160cmd = @set -e; $(echo-cmd) $($(quiet)redirect) $(delete-on-interrupt) $(cmd_$(1))
161
162###
163# if_changed - execute command if any prerequisite is newer than
164# target, or command line has changed
165# if_changed_dep - as if_changed, but uses fixdep to reveal dependencies
166# including used config symbols
167# if_changed_rule - as if_changed but execute rule instead
168# See Documentation/kbuild/makefiles.rst for more info
169
170ifneq ($(KBUILD_NOCMDDEP),1)
171# Check if both commands are the same including their order. Result is empty
172# string if equal. User may override this check using make KBUILD_NOCMDDEP=1
173cmd-check = $(filter-out $(subst $(space),$(space_escape),$(strip $(cmd_$@))), \
174 $(subst $(space),$(space_escape),$(strip $(cmd_$1))))
175else
176cmd-check = $(if $(strip $(cmd_$@)),,1)
177endif
178
179# Replace >$< with >$$< to preserve $ when reloading the .cmd file
180# (needed for make)
181# Replace >#< with >$(pound)< to avoid starting a comment in the .cmd file
182# (needed for make)
183# Replace >'< with >'\''< to be able to enclose the whole string in '...'
184# (needed for the shell)
185make-cmd = $(call escsq,$(subst $(pound),$$(pound),$(subst $$,$$$$,$(cmd_$(1)))))
186
187# Find any prerequisites that are newer than target or that do not exist.
188# PHONY targets skipped in both cases.
189newer-prereqs = $(filter-out $(PHONY),$?)
190
191# It is a typical mistake to forget the FORCE prerequisite. Check it here so
192# no more breakage will slip in.
193check-FORCE = $(if $(filter FORCE, $^),,$(warning FORCE prerequisite is missing))
194
195if-changed-cond = $(newer-prereqs)$(cmd-check)$(check-FORCE)
196
197# Execute command if command has changed or prerequisite(s) are updated.
198if_changed = $(if $(if-changed-cond),$(cmd_and_savecmd),@:)
199
200cmd_and_savecmd = \
201 $(cmd); \
202 printf '%s\n' 'cmd_$@ := $(make-cmd)' > $(dot-target).cmd
203
204# Execute the command and also postprocess generated .d dependencies file.
205if_changed_dep = $(if $(if-changed-cond),$(cmd_and_fixdep),@:)
206
207cmd_and_fixdep = \
208 $(cmd); \
209 scripts/basic/fixdep $(depfile) $@ '$(make-cmd)' > $(dot-target).cmd;\
210 rm -f $(depfile)
211
212# Usage: $(call if_changed_rule,foo)
213# Will check if $(cmd_foo) or any of the prerequisites changed,
214# and if so will execute $(rule_foo).
215if_changed_rule = $(if $(if-changed-cond),$(rule_$(1)),@:)
216
217###
218# why - tell why a target got built
219# enabled by make V=2
220# Output (listed in the order they are checked):
221# (1) - due to target is PHONY
222# (2) - due to target missing
223# (3) - due to: file1.h file2.h
224# (4) - due to command line change
225# (5) - due to missing .cmd file
226# (6) - due to target not in $(targets)
227# (1) PHONY targets are always build
228# (2) No target, so we better build it
229# (3) Prerequisite is newer than target
230# (4) The command line stored in the file named dir/.target.cmd
231# differed from actual command line. This happens when compiler
232# options changes
233# (5) No dir/.target.cmd file (used to store command line)
234# (6) No dir/.target.cmd file and target not listed in $(targets)
235# This is a good hint that there is a bug in the kbuild file
236ifeq ($(KBUILD_VERBOSE),2)
237why = \
238 $(if $(filter $@, $(PHONY)),- due to target is PHONY, \
239 $(if $(wildcard $@), \
240 $(if $(newer-prereqs),- due to: $(newer-prereqs), \
241 $(if $(cmd-check), \
242 $(if $(cmd_$@),- due to command line change, \
243 $(if $(filter $@, $(targets)), \
244 - due to missing .cmd file, \
245 - due to $(notdir $@) not in $$(targets) \
246 ) \
247 ) \
248 ) \
249 ), \
250 - due to target missing \
251 ) \
252 )
253
254echo-why = $(call escsq, $(strip $(why)))
255endif
256
257###############################################################################
258
259# delete partially updated (i.e. corrupted) files on error
260.DELETE_ON_ERROR:
261
262# do not delete intermediate files automatically
263#
264# .NOTINTERMEDIATE is more correct, but only available on newer Make versions.
265# Make 4.4 introduced .NOTINTERMEDIATE, and it appears in .FEATURES, but the
266# global .NOTINTERMEDIATE does not work. We can use it on Make > 4.4.
267# Use .SECONDARY for older Make versions, but "newer-prereq" cannot detect
268# deleted files.
269ifneq ($(and $(filter notintermediate, $(.FEATURES)),$(filter-out 4.4,$(MAKE_VERSION))),)
270.NOTINTERMEDIATE:
271else
272.SECONDARY:
273endif
1####
2# kbuild: Generic definitions
3
4# Convenient variables
5comma := ,
6quote := "
7squote := '
8empty :=
9space := $(empty) $(empty)
10space_escape := _-_SPACE_-_
11
12###
13# Name of target with a '.' as filename prefix. foo/bar.o => foo/.bar.o
14dot-target = $(dir $@).$(notdir $@)
15
16###
17# The temporary file to save gcc -MD generated dependencies must not
18# contain a comma
19depfile = $(subst $(comma),_,$(dot-target).d)
20
21###
22# filename of target with directory and extension stripped
23basetarget = $(basename $(notdir $@))
24
25###
26# filename of first prerequisite with directory and extension stripped
27baseprereq = $(basename $(notdir $<))
28
29###
30# Escape single quote for use in echo statements
31escsq = $(subst $(squote),'\$(squote)',$1)
32
33###
34# Easy method for doing a status message
35 kecho := :
36 quiet_kecho := echo
37silent_kecho := :
38kecho := $($(quiet)kecho)
39
40###
41# filechk is used to check if the content of a generated file is updated.
42# Sample usage:
43# define filechk_sample
44# echo $KERNELRELEASE
45# endef
46# version.h : Makefile
47# $(call filechk,sample)
48# The rule defined shall write to stdout the content of the new file.
49# The existing file will be compared with the new one.
50# - If no file exist it is created
51# - If the content differ the new file is used
52# - If they are equal no change, and no timestamp update
53# - stdin is piped in from the first prerequisite ($<) so one has
54# to specify a valid file as first prerequisite (often the kbuild file)
55define filechk
56 $(Q)set -e; \
57 $(kecho) ' CHK $@'; \
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" is can be used as temporary file and
89# is 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 "$$TMP" -,$(2),$(3))
110
111# Do not attempt to build with gcc plugins during cc-option tests.
112# (And this uses delayed resolution so the flags will be up to date.)
113CC_OPTION_CFLAGS = $(filter-out $(GCC_PLUGINS_CFLAGS),$(KBUILD_CFLAGS))
114
115# cc-option
116# Usage: cflags-y += $(call cc-option,-march=winchip-c6,-march=i586)
117
118cc-option = $(call try-run,\
119 $(CC) $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",$(1),$(2))
120
121# cc-option-yn
122# Usage: flag := $(call cc-option-yn,-march=winchip-c6)
123cc-option-yn = $(call try-run,\
124 $(CC) $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",y,n)
125
126# cc-option-align
127# Prefix align with either -falign or -malign
128cc-option-align = $(subst -functions=0,,\
129 $(call cc-option,-falign-functions=0,-malign-functions=0))
130
131# cc-disable-warning
132# Usage: cflags-y += $(call cc-disable-warning,unused-but-set-variable)
133cc-disable-warning = $(call try-run,\
134 $(CC) $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1)))
135
136# cc-name
137# Expands to either gcc or clang
138cc-name = $(shell $(CC) -v 2>&1 | grep -q "clang version" && echo clang || echo gcc)
139
140# cc-version
141cc-version = $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-version.sh $(CC))
142
143# cc-fullversion
144cc-fullversion = $(shell $(CONFIG_SHELL) \
145 $(srctree)/scripts/gcc-version.sh -p $(CC))
146
147# cc-ifversion
148# Usage: EXTRA_CFLAGS += $(call cc-ifversion, -lt, 0402, -O1)
149cc-ifversion = $(shell [ $(cc-version) $(1) $(2) ] && echo $(3) || echo $(4))
150
151# cc-ldoption
152# Usage: ldflags += $(call cc-ldoption, -Wl$(comma)--hash-style=both)
153cc-ldoption = $(call try-run,\
154 $(CC) $(1) -nostdlib -x c /dev/null -o "$$TMP",$(1),$(2))
155
156# ld-option
157# Usage: LDFLAGS += $(call ld-option, -X)
158ld-option = $(call try-run,\
159 $(CC) -x c /dev/null -c -o "$$TMPO" ; $(LD) $(1) "$$TMPO" -o "$$TMP",$(1),$(2))
160
161# ar-option
162# Usage: KBUILD_ARFLAGS := $(call ar-option,D)
163# Important: no spaces around options
164ar-option = $(call try-run, $(AR) rc$(1) "$$TMP",$(1),$(2))
165
166# ld-version
167# Note this is mainly for HJ Lu's 3 number binutil versions
168ld-version = $(shell $(LD) --version | $(srctree)/scripts/ld-version.sh)
169
170# ld-ifversion
171# Usage: $(call ld-ifversion, -ge, 22252, y)
172ld-ifversion = $(shell [ $(ld-version) $(1) $(2) ] && echo $(3) || echo $(4))
173
174######
175
176###
177# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj=
178# Usage:
179# $(Q)$(MAKE) $(build)=dir
180build := -f $(srctree)/scripts/Makefile.build obj
181
182###
183# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.modbuiltin obj=
184# Usage:
185# $(Q)$(MAKE) $(modbuiltin)=dir
186modbuiltin := -f $(srctree)/scripts/Makefile.modbuiltin obj
187
188###
189# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.dtbinst obj=
190# Usage:
191# $(Q)$(MAKE) $(dtbinst)=dir
192dtbinst := -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.dtbinst obj
193
194###
195# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.clean obj=
196# Usage:
197# $(Q)$(MAKE) $(clean)=dir
198clean := -f $(srctree)/scripts/Makefile.clean obj
199
200###
201# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.headersinst obj=
202# Usage:
203# $(Q)$(MAKE) $(hdr-inst)=dir
204hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
205
206# Prefix -I with $(srctree) if it is not an absolute path.
207# skip if -I has no parameter
208addtree = $(if $(patsubst -I%,%,$(1)), \
209$(if $(filter-out -I/% -I./% -I../%,$(1)),$(patsubst -I%,-I$(srctree)/%,$(1)),$(1)))
210
211# Find all -I options and call addtree
212flags = $(foreach o,$($(1)),$(if $(filter -I%,$(o)),$(call addtree,$(o)),$(o)))
213
214# echo command.
215# Short version is used, if $(quiet) equals `quiet_', otherwise full one.
216echo-cmd = $(if $($(quiet)cmd_$(1)),\
217 echo ' $(call escsq,$($(quiet)cmd_$(1)))$(echo-why)';)
218
219# printing commands
220cmd = @$(echo-cmd) $(cmd_$(1))
221
222# Add $(obj)/ for paths that are not absolute
223objectify = $(foreach o,$(1),$(if $(filter /%,$(o)),$(o),$(obj)/$(o)))
224
225###
226# if_changed - execute command if any prerequisite is newer than
227# target, or command line has changed
228# if_changed_dep - as if_changed, but uses fixdep to reveal dependencies
229# including used config symbols
230# if_changed_rule - as if_changed but execute rule instead
231# See Documentation/kbuild/makefiles.txt for more info
232
233ifneq ($(KBUILD_NOCMDDEP),1)
234# Check if both arguments are the same including their order. Result is empty
235# string if equal. User may override this check using make KBUILD_NOCMDDEP=1
236arg-check = $(filter-out $(subst $(space),$(space_escape),$(strip $(cmd_$@))), \
237 $(subst $(space),$(space_escape),$(strip $(cmd_$1))))
238else
239arg-check = $(if $(strip $(cmd_$@)),,1)
240endif
241
242# Replace >$< with >$$< to preserve $ when reloading the .cmd file
243# (needed for make)
244# Replace >#< with >\#< to avoid starting a comment in the .cmd file
245# (needed for make)
246# Replace >'< with >'\''< to be able to enclose the whole string in '...'
247# (needed for the shell)
248make-cmd = $(call escsq,$(subst \#,\\\#,$(subst $$,$$$$,$(cmd_$(1)))))
249
250# Find any prerequisites that is newer than target or that does not exist.
251# PHONY targets skipped in both cases.
252any-prereq = $(filter-out $(PHONY),$?) $(filter-out $(PHONY) $(wildcard $^),$^)
253
254# Execute command if command has changed or prerequisite(s) are updated.
255#
256if_changed = $(if $(strip $(any-prereq) $(arg-check)), \
257 @set -e; \
258 $(echo-cmd) $(cmd_$(1)); \
259 printf '%s\n' 'cmd_$@ := $(make-cmd)' > $(dot-target).cmd, @:)
260
261# Execute the command and also postprocess generated .d dependencies file.
262if_changed_dep = $(if $(strip $(any-prereq) $(arg-check) ), \
263 @set -e; \
264 $(cmd_and_fixdep), @:)
265
266ifndef CONFIG_TRIM_UNUSED_KSYMS
267
268cmd_and_fixdep = \
269 $(echo-cmd) $(cmd_$(1)); \
270 scripts/basic/fixdep $(depfile) $@ '$(make-cmd)' > $(dot-target).tmp;\
271 rm -f $(depfile); \
272 mv -f $(dot-target).tmp $(dot-target).cmd;
273
274else
275
276# Filter out exported kernel symbol names from the preprocessor output.
277# See also __KSYM_DEPS__ in include/linux/export.h.
278# We disable the depfile generation here, so as not to overwrite the existing
279# depfile while fixdep is parsing it.
280flags_nodeps = $(filter-out -Wp$(comma)-M%, $($(1)))
281ksym_dep_filter = \
282 case "$(1)" in \
283 cc_*_c|cpp_i_c) \
284 $(CPP) $(call flags_nodeps,c_flags) -D__KSYM_DEPS__ $< ;; \
285 as_*_S|cpp_s_S) \
286 $(CPP) $(call flags_nodeps,a_flags) -D__KSYM_DEPS__ $< ;; \
287 boot*|build*|*cpp_lds_S|dtc|host*|vdso*) : ;; \
288 *) echo "Don't know how to preprocess $(1)" >&2; false ;; \
289 esac | tr ";" "\n" | sed -rn 's/^.*=== __KSYM_(.*) ===.*$$/KSYM_\1/p'
290
291cmd_and_fixdep = \
292 $(echo-cmd) $(cmd_$(1)); \
293 $(ksym_dep_filter) | \
294 scripts/basic/fixdep -e $(depfile) $@ '$(make-cmd)' \
295 > $(dot-target).tmp; \
296 rm -f $(depfile); \
297 mv -f $(dot-target).tmp $(dot-target).cmd;
298
299endif
300
301# Usage: $(call if_changed_rule,foo)
302# Will check if $(cmd_foo) or any of the prerequisites changed,
303# and if so will execute $(rule_foo).
304if_changed_rule = $(if $(strip $(any-prereq) $(arg-check) ), \
305 @set -e; \
306 $(rule_$(1)), @:)
307
308###
309# why - tell why a a target got build
310# enabled by make V=2
311# Output (listed in the order they are checked):
312# (1) - due to target is PHONY
313# (2) - due to target missing
314# (3) - due to: file1.h file2.h
315# (4) - due to command line change
316# (5) - due to missing .cmd file
317# (6) - due to target not in $(targets)
318# (1) PHONY targets are always build
319# (2) No target, so we better build it
320# (3) Prerequisite is newer than target
321# (4) The command line stored in the file named dir/.target.cmd
322# differed from actual command line. This happens when compiler
323# options changes
324# (5) No dir/.target.cmd file (used to store command line)
325# (6) No dir/.target.cmd file and target not listed in $(targets)
326# This is a good hint that there is a bug in the kbuild file
327ifeq ($(KBUILD_VERBOSE),2)
328why = \
329 $(if $(filter $@, $(PHONY)),- due to target is PHONY, \
330 $(if $(wildcard $@), \
331 $(if $(strip $(any-prereq)),- due to: $(any-prereq), \
332 $(if $(arg-check), \
333 $(if $(cmd_$@),- due to command line change, \
334 $(if $(filter $@, $(targets)), \
335 - due to missing .cmd file, \
336 - due to $(notdir $@) not in $$(targets) \
337 ) \
338 ) \
339 ) \
340 ), \
341 - due to target missing \
342 ) \
343 )
344
345echo-why = $(call escsq, $(strip $(why)))
346endif
347
348###############################################################################
349#
350# When a Kconfig string contains a filename, it is suitable for
351# passing to shell commands. It is surrounded by double-quotes, and
352# any double-quotes or backslashes within it are escaped by
353# backslashes.
354#
355# This is no use for dependencies or $(wildcard). We need to strip the
356# surrounding quotes and the escaping from quotes and backslashes, and
357# we *do* need to escape any spaces in the string. So, for example:
358#
359# Usage: $(eval $(call config_filename,FOO))
360#
361# Defines FOO_FILENAME based on the contents of the CONFIG_FOO option,
362# transformed as described above to be suitable for use within the
363# makefile.
364#
365# Also, if the filename is a relative filename and exists in the source
366# tree but not the build tree, define FOO_SRCPREFIX as $(srctree)/ to
367# be prefixed to *both* command invocation and dependencies.
368#
369# Note: We also print the filenames in the quiet_cmd_foo text, and
370# perhaps ought to have a version specially escaped for that purpose.
371# But it's only cosmetic, and $(patsubst "%",%,$(CONFIG_FOO)) is good
372# enough. It'll strip the quotes in the common case where there's no
373# space and it's a simple filename, and it'll retain the quotes when
374# there's a space. There are some esoteric cases in which it'll print
375# the wrong thing, but we don't really care. The actual dependencies
376# and commands *do* get it right, with various combinations of single
377# and double quotes, backslashes and spaces in the filenames.
378#
379###############################################################################
380#
381define config_filename
382ifneq ($$(CONFIG_$(1)),"")
383$(1)_FILENAME := $$(subst \\,\,$$(subst \$$(quote),$$(quote),$$(subst $$(space_escape),\$$(space),$$(patsubst "%",%,$$(subst $$(space),$$(space_escape),$$(CONFIG_$(1)))))))
384ifneq ($$(patsubst /%,%,$$(firstword $$($(1)_FILENAME))),$$(firstword $$($(1)_FILENAME)))
385else
386ifeq ($$(wildcard $$($(1)_FILENAME)),)
387ifneq ($$(wildcard $$(srctree)/$$($(1)_FILENAME)),)
388$(1)_SRCPREFIX := $(srctree)/
389endif
390endif
391endif
392endif
393endef
394#
395###############################################################################