1 # SPDX-License-Identifier: GPL-2.0 <<
2 #### 1 ####
3 # kbuild: Generic definitions 2 # kbuild: Generic definitions
4 3
5 # Convenient variables 4 # Convenient variables
6 comma := , 5 comma := ,
7 quote := " <<
8 squote := ' 6 squote := '
9 empty := 7 empty :=
10 space := $(empty) $(empty) 8 space := $(empty) $(empty)
11 space_escape := _-_SPACE_-_ <<
12 pound := \# <<
13 define newline <<
14 <<
15 <<
16 endef <<
17 <<
18 ### <<
19 # Comparison macros. <<
20 # Usage: $(call test-lt, $(CONFIG_LLD_VERSION) <<
21 # <<
22 # Use $(intcmp ...) if supported. (Make >= 4.4 <<
23 # Otherwise, fall back to the 'test' shell com <<
24 ifeq ($(intcmp 1,0,,,y),y) <<
25 test-ge = $(intcmp $(strip $1)0, $(strip $2)0, <<
26 test-gt = $(intcmp $(strip $1)0, $(strip $2)0, <<
27 else <<
28 test-ge = $(shell test $(strip $1)0 -ge $(stri <<
29 test-gt = $(shell test $(strip $1)0 -gt $(stri <<
30 endif <<
31 test-le = $(call test-ge, $2, $1) <<
32 test-lt = $(call test-gt, $2, $1) <<
33 9
34 ### 10 ###
35 # Name of target with a '.' as filename prefix 11 # Name of target with a '.' as filename prefix. foo/bar.o => foo/.bar.o
36 dot-target = $(dir $@).$(notdir $@) 12 dot-target = $(dir $@).$(notdir $@)
37 13
38 ### 14 ###
39 # Name of target with a '.tmp_' as filename pr !! 15 # The temporary file to save gcc -MD generated dependencies must not
40 tmp-target = $(dir $@).tmp_$(notdir $@) <<
41 <<
42 ### <<
43 # The temporary file to save gcc -MMD generate <<
44 # contain a comma 16 # contain a comma
45 depfile = $(subst $(comma),_,$(dot-target).d) 17 depfile = $(subst $(comma),_,$(dot-target).d)
46 18
47 ### 19 ###
48 # filename of target with directory and extens 20 # filename of target with directory and extension stripped
49 basetarget = $(basename $(notdir $@)) 21 basetarget = $(basename $(notdir $@))
50 22
51 ### 23 ###
52 # real prerequisites without phony targets !! 24 # filename of first prerequisite with directory and extension stripped
53 real-prereqs = $(filter-out $(PHONY), $^) !! 25 baseprereq = $(basename $(notdir $<))
54 26
55 ### 27 ###
56 # Escape single quote for use in echo statemen 28 # Escape single quote for use in echo statements
57 escsq = $(subst $(squote),'\$(squote)',$1) 29 escsq = $(subst $(squote),'\$(squote)',$1)
58 30
59 ### 31 ###
60 # Quote a string to pass it to C files. foo => <<
61 stringify = $(squote)$(quote)$1$(quote)$(squot <<
62 <<
63 ### <<
64 # The path to Kbuild or Makefile. Kbuild has p <<
65 kbuild-file = $(or $(wildcard $(src)/Kbuild),$ <<
66 <<
67 ### <<
68 # Read a file, replacing newlines with spaces <<
69 # <<
70 # Make 4.2 or later can read a file by using i <<
71 ifneq ($(filter-out 4.0 4.1, $(MAKE_VERSION)), <<
72 read-file = $(subst $(newline),$(space),$(file <<
73 else <<
74 read-file = $(shell cat $1 2>/dev/null) <<
75 endif <<
76 <<
77 ### <<
78 # Easy method for doing a status message 32 # Easy method for doing a status message
79 kecho := : 33 kecho := :
80 quiet_kecho := echo 34 quiet_kecho := echo
81 silent_kecho := : 35 silent_kecho := :
82 kecho := $($(quiet)kecho) 36 kecho := $($(quiet)kecho)
83 37
84 ### 38 ###
85 # filechk is used to check if the content of a 39 # filechk is used to check if the content of a generated file is updated.
86 # Sample usage: 40 # Sample usage:
87 # !! 41 # define filechk_sample
88 # filechk_sample = echo $(KERNELRELEASE) !! 42 # echo $KERNELRELEASE
89 # version.h: FORCE !! 43 # endef
>> 44 # version.h : Makefile
90 # $(call filechk,sample) 45 # $(call filechk,sample)
91 # <<
92 # The rule defined shall write to stdout the c 46 # The rule defined shall write to stdout the content of the new file.
93 # The existing file will be compared with the 47 # The existing file will be compared with the new one.
94 # - If no file exist it is created 48 # - If no file exist it is created
95 # - If the content differ the new file is used 49 # - If the content differ the new file is used
96 # - If they are equal no change, and no timest 50 # - If they are equal no change, and no timestamp update
>> 51 # - stdin is piped in from the first prerequisite ($<) so one has
>> 52 # to specify a valid file as first prerequisite (often the kbuild file)
97 define filechk 53 define filechk
98 $(check-FORCE) !! 54 $(Q)set -e; \
99 $(Q)set -e; !! 55 $(kecho) ' CHK $@'; \
100 mkdir -p $(dir $@); !! 56 mkdir -p $(dir $@); \
101 trap "rm -f $(tmp-target)" EXIT; !! 57 $(filechk_$(1)) < $< > $@.tmp; \
102 { $(filechk_$(1)); } > $(tmp-target); !! 58 if [ -r $@ ] && cmp -s $@ $@.tmp; then \
103 if [ ! -r $@ ] || ! cmp -s $@ $(tmp-ta !! 59 rm -f $@.tmp; \
104 $(kecho) ' UPD $@'; !! 60 else \
105 mv -f $(tmp-target) $@; !! 61 $(kecho) ' UPD $@'; \
>> 62 mv -f $@.tmp $@; \
106 fi 63 fi
107 endef 64 endef
108 65
>> 66 ######
>> 67 # gcc support functions
>> 68 # See documentation in Documentation/kbuild/makefiles.txt
>> 69
>> 70 # cc-cross-prefix
>> 71 # Usage: CROSS_COMPILE := $(call cc-cross-prefix, m68k-linux-gnu- m68k-linux-)
>> 72 # Return first prefix where a prefix$(CC) is found in PATH.
>> 73 # If no $(CC) found in PATH with listed prefixes return nothing
>> 74 cc-cross-prefix = \
>> 75 $(word 1, $(foreach c,$(1), \
>> 76 $(shell set -e; \
>> 77 if (which $(strip $(c))$(CC)) > /dev/null 2>&1 ; then \
>> 78 echo $(c); \
>> 79 fi)))
>> 80
>> 81 # output directory for tests below
>> 82 TMPOUT := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/)
>> 83
>> 84 # try-run
>> 85 # Usage: option = $(call try-run, $(CC)...-o "$$TMP",option-ok,otherwise)
>> 86 # Exit code chooses option. "$$TMP" is can be used as temporary file and
>> 87 # is automatically cleaned up.
>> 88 try-run = $(shell set -e; \
>> 89 TMP="$(TMPOUT).$$$$.tmp"; \
>> 90 TMPO="$(TMPOUT).$$$$.o"; \
>> 91 if ($(1)) >/dev/null 2>&1; \
>> 92 then echo "$(2)"; \
>> 93 else echo "$(3)"; \
>> 94 fi; \
>> 95 rm -f "$$TMP" "$$TMPO")
>> 96
>> 97 # as-option
>> 98 # Usage: cflags-y += $(call as-option,-Wa$(comma)-isa=foo,)
>> 99
>> 100 as-option = $(call try-run,\
>> 101 $(CC) $(KBUILD_CFLAGS) $(1) -c -x assembler /dev/null -o "$$TMP",$(1),$(2))
>> 102
>> 103 # as-instr
>> 104 # Usage: cflags-y += $(call as-instr,instr,option1,option2)
>> 105
>> 106 as-instr = $(call try-run,\
>> 107 printf "%b\n" "$(1)" | $(CC) $(KBUILD_AFLAGS) -c -x assembler -o "$$TMP" -,$(2),$(3))
>> 108
>> 109 # cc-option
>> 110 # Usage: cflags-y += $(call cc-option,-march=winchip-c6,-march=i586)
>> 111
>> 112 cc-option = $(call try-run,\
>> 113 $(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",$(1),$(2))
>> 114
>> 115 # cc-option-yn
>> 116 # Usage: flag := $(call cc-option-yn,-march=winchip-c6)
>> 117 cc-option-yn = $(call try-run,\
>> 118 $(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",y,n)
>> 119
>> 120 # cc-option-align
>> 121 # Prefix align with either -falign or -malign
>> 122 cc-option-align = $(subst -functions=0,,\
>> 123 $(call cc-option,-falign-functions=0,-malign-functions=0))
>> 124
>> 125 # cc-disable-warning
>> 126 # Usage: cflags-y += $(call cc-disable-warning,unused-but-set-variable)
>> 127 cc-disable-warning = $(call try-run,\
>> 128 $(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1)))
>> 129
>> 130 # cc-version
>> 131 # Usage gcc-ver := $(call cc-version)
>> 132 cc-version = $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-version.sh $(CC))
>> 133
>> 134 # cc-fullversion
>> 135 # Usage gcc-ver := $(call cc-fullversion)
>> 136 cc-fullversion = $(shell $(CONFIG_SHELL) \
>> 137 $(srctree)/scripts/gcc-version.sh -p $(CC))
>> 138
>> 139 # cc-ifversion
>> 140 # Usage: EXTRA_CFLAGS += $(call cc-ifversion, -lt, 0402, -O1)
>> 141 cc-ifversion = $(shell [ $(call cc-version, $(CC)) $(1) $(2) ] && echo $(3))
>> 142
>> 143 # cc-ldoption
>> 144 # Usage: ldflags += $(call cc-ldoption, -Wl$(comma)--hash-style=both)
>> 145 cc-ldoption = $(call try-run,\
>> 146 $(CC) $(1) -nostdlib -x c /dev/null -o "$$TMP",$(1),$(2))
>> 147
>> 148 # ld-option
>> 149 # Usage: LDFLAGS += $(call ld-option, -X)
>> 150 ld-option = $(call try-run,\
>> 151 $(CC) -x c /dev/null -c -o "$$TMPO" ; $(LD) $(1) "$$TMPO" -o "$$TMP",$(1),$(2))
>> 152
>> 153 # ar-option
>> 154 # Usage: KBUILD_ARFLAGS := $(call ar-option,D)
>> 155 # Important: no spaces around options
>> 156 ar-option = $(call try-run, $(AR) rc$(1) "$$TMP",$(1),$(2))
>> 157
>> 158 ######
>> 159
109 ### 160 ###
110 # Shorthand for $(Q)$(MAKE) -f scripts/Makefil 161 # Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj=
111 # Usage: 162 # Usage:
112 # $(Q)$(MAKE) $(build)=dir 163 # $(Q)$(MAKE) $(build)=dir
113 build := -f $(srctree)/scripts/Makefile.build !! 164 build := -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.build obj
114 165
115 ### 166 ###
116 # Shorthand for $(Q)$(MAKE) -f scripts/Makefil !! 167 # Shorthand for $(Q)$(MAKE) -f scripts/Makefile.modbuiltin obj=
117 # Usage: 168 # Usage:
118 # $(Q)$(MAKE) $(clean)=dir !! 169 # $(Q)$(MAKE) $(modbuiltin)=dir
119 clean := -f $(srctree)/scripts/Makefile.clean !! 170 modbuiltin := -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.modbuiltin obj
120 171
121 # pring log !! 172 # Prefix -I with $(srctree) if it is not an absolute path.
122 # !! 173 # skip if -I has no parameter
123 # If quiet is "silent_", print nothing and sin !! 174 addtree = $(if $(patsubst -I%,%,$(1)), \
124 # If quiet is "quiet_", print short log !! 175 $(if $(filter-out -I/%,$(1)),$(patsubst -I%,-I$(srctree)/%,$(1))) $(1))
125 # If quiet is empty, print short log and whole !! 176
126 silent_log_print = exec >/dev/null; !! 177 # Find all -I options and call addtree
127 quiet_log_print = $(if $(quiet_cmd_$1), echo !! 178 flags = $(foreach o,$($(1)),$(if $(filter -I%,$(o)),$(call addtree,$(o)),$(o)))
128 log_print = echo '$(pound) $(call escsq !! 179
129 echo ' $(call escsq,$(cmd_ !! 180 # echo command.
>> 181 # Short version is used, if $(quiet) equals `quiet_', otherwise full one.
>> 182 echo-cmd = $(if $($(quiet)cmd_$(1)),\
>> 183 echo ' $(call escsq,$($(quiet)cmd_$(1)))$(echo-why)';)
130 184
131 # Delete the target on interruption !! 185 # printing commands
132 # !! 186 cmd = @$(echo-cmd) $(cmd_$(1))
133 # GNU Make automatically deletes the target if <<
134 # the interrupted recipe. So, you can safely s <<
135 # will delete incomplete targets), and resume <<
136 # <<
137 # However, this does not work when the stderr <<
138 # $ make >&2 | tee log <<
139 # Make dies with SIGPIPE before cleaning the t <<
140 # <<
141 # To address it, we clean the target in signal <<
142 # <<
143 # Make deletes the target when it catches SIGH <<
144 # So, we cover them, and also SIGPIPE just in <<
145 # <<
146 # Of course, this is unneeded for phony target <<
147 delete-on-interrupt = \ <<
148 $(if $(filter-out $(PHONY), $@), \ <<
149 $(foreach sig, HUP INT QUIT TE <<
150 trap 'rm -f $@; trap - <<
151 187
152 # print and execute commands !! 188 # Add $(obj)/ for paths that are not absolute
153 cmd = @$(if $(cmd_$(1)),set -e; $($(quiet)log_ !! 189 objectify = $(foreach o,$(1),$(if $(filter /%,$(o)),$(o),$(obj)/$(o)))
154 190
155 ### 191 ###
156 # if_changed - execute command if any pre 192 # if_changed - execute command if any prerequisite is newer than
157 # target, or command line ha 193 # target, or command line has changed
158 # if_changed_dep - as if_changed, but uses fi 194 # if_changed_dep - as if_changed, but uses fixdep to reveal dependencies
159 # including used config symb 195 # including used config symbols
160 # if_changed_rule - as if_changed but execute 196 # if_changed_rule - as if_changed but execute rule instead
161 # See Documentation/kbuild/makefiles.rst for m !! 197 # See Documentation/kbuild/makefiles.txt for more info
162 198
163 ifneq ($(KBUILD_NOCMDDEP),1) 199 ifneq ($(KBUILD_NOCMDDEP),1)
164 # Check if both commands are the same includin !! 200 # Check if both arguments has same arguments. Result is empty string if equal.
165 # string if equal. User may override this chec !! 201 # User may override this check using make KBUILD_NOCMDDEP=1
166 # If the target does not exist, the *.cmd file !! 202 arg-check = $(strip $(filter-out $(cmd_$(1)), $(cmd_$@)) \
167 # $(savedcmd_$@) gets empty. Then, target will !! 203 $(filter-out $(cmd_$@), $(cmd_$(1))) )
168 # happens to become empty. <<
169 cmd-check = $(filter-out $(subst $(space),$(sp <<
170 $(subst $(space),$(sp <<
171 else 204 else
172 # We still need to detect missing targets. !! 205 arg-check = $(if $(strip $(cmd_$@)),,1)
173 cmd-check = $(if $(strip $(savedcmd_$@)),,1) <<
174 endif 206 endif
175 207
176 # Replace >$< with >$$< to preserve $ when rel !! 208 # >'< substitution is for echo to work,
177 # (needed for make) !! 209 # >$< substitution to preserve $ when reloading .cmd file
178 # Replace >#< with >$(pound)< to avoid startin !! 210 # note: when using inline perl scripts [perl -e '...$$t=1;...']
179 # (needed for make) !! 211 # in $(cmd_xxx) double $$ your perl vars
180 # Replace >'< with >'\''< to be able to enclos !! 212 make-cmd = $(subst \\,\\\\,$(subst \#,\\\#,$(subst $$,$$$$,$(call escsq,$(cmd_$(1))))))
181 # (needed for the shell) <<
182 make-cmd = $(call escsq,$(subst $(pound),$$(po <<
183 213
184 # Find any prerequisites that are newer than t !! 214 # Find any prerequisites that is newer than target or that does not exist.
185 # PHONY targets skipped in both cases. 215 # PHONY targets skipped in both cases.
186 # If there is no prerequisite other than phony !! 216 any-prereq = $(filter-out $(PHONY),$?) $(filter-out $(PHONY) $(wildcard $^),$^)
187 # empty even if the target does not exist. cmd <<
188 newer-prereqs = $(filter-out $(PHONY),$?) <<
189 <<
190 # It is a typical mistake to forget the FORCE <<
191 # no more breakage will slip in. <<
192 check-FORCE = $(if $(filter FORCE, $^),,$(warn <<
193 <<
194 if-changed-cond = $(newer-prereqs)$(cmd-check) <<
195 217
196 # Execute command if command has changed or pr 218 # Execute command if command has changed or prerequisite(s) are updated.
197 if_changed = $(if $(if-changed-cond),$(cmd_and !! 219 #
198 !! 220 if_changed = $(if $(strip $(any-prereq) $(arg-check)), \
199 cmd_and_savecmd = !! 221 @set -e; \
200 $(cmd); !! 222 $(echo-cmd) $(cmd_$(1)); \
201 printf '%s\n' 'savedcmd_$@ := $(make-c !! 223 echo 'cmd_$@ := $(make-cmd)' > $(dot-target).cmd)
202 224
203 # Execute the command and also postprocess gen 225 # Execute the command and also postprocess generated .d dependencies file.
204 if_changed_dep = $(if $(if-changed-cond),$(cmd !! 226 if_changed_dep = $(if $(strip $(any-prereq) $(arg-check) ), \
205 !! 227 @set -e; \
206 cmd_and_fixdep = !! 228 $(echo-cmd) $(cmd_$(1)); \
207 $(cmd); !! 229 scripts/basic/fixdep $(depfile) $@ '$(make-cmd)' > $(dot-target).tmp;\
208 scripts/basic/fixdep $(depfile) $@ '$( !! 230 rm -f $(depfile); \
209 rm -f $(depfile) !! 231 mv -f $(dot-target).tmp $(dot-target).cmd)
210 232
211 # Usage: $(call if_changed_rule,foo) 233 # Usage: $(call if_changed_rule,foo)
212 # Will check if $(cmd_foo) or any of the prere 234 # Will check if $(cmd_foo) or any of the prerequisites changed,
213 # and if so will execute $(rule_foo). 235 # and if so will execute $(rule_foo).
214 if_changed_rule = $(if $(if-changed-cond),$(ru !! 236 if_changed_rule = $(if $(strip $(any-prereq) $(arg-check) ), \
>> 237 @set -e; \
>> 238 $(rule_$(1)))
215 239
216 ### 240 ###
217 # why - tell why a target got built !! 241 # why - tell why a a target got build
218 # enabled by make V=2 242 # enabled by make V=2
219 # Output (listed in the order they are c 243 # Output (listed in the order they are checked):
220 # (1) - due to target is PHONY 244 # (1) - due to target is PHONY
221 # (2) - due to target missing 245 # (2) - due to target missing
222 # (3) - due to: file1.h file2.h 246 # (3) - due to: file1.h file2.h
223 # (4) - due to command line change 247 # (4) - due to command line change
224 # (5) - due to missing .cmd file 248 # (5) - due to missing .cmd file
225 # (6) - due to target not in $(target 249 # (6) - due to target not in $(targets)
226 # (1) PHONY targets are always build 250 # (1) PHONY targets are always build
227 # (2) No target, so we better build it 251 # (2) No target, so we better build it
228 # (3) Prerequisite is newer than target 252 # (3) Prerequisite is newer than target
229 # (4) The command line stored in the file name 253 # (4) The command line stored in the file named dir/.target.cmd
230 # differed from actual command line. This 254 # differed from actual command line. This happens when compiler
231 # options changes 255 # options changes
232 # (5) No dir/.target.cmd file (used to store c 256 # (5) No dir/.target.cmd file (used to store command line)
233 # (6) No dir/.target.cmd file and target not l 257 # (6) No dir/.target.cmd file and target not listed in $(targets)
234 # This is a good hint that there is a bug 258 # This is a good hint that there is a bug in the kbuild file
235 ifneq ($(findstring 2, $(KBUILD_VERBOSE)),) !! 259 ifeq ($(KBUILD_VERBOSE),2)
236 _why = !! 260 why = \
237 $(if $(filter $@, $(PHONY)),- due to targe 261 $(if $(filter $@, $(PHONY)),- due to target is PHONY, \
238 $(if $(wildcard $@), 262 $(if $(wildcard $@), \
239 $(if $(newer-prereqs),- due to: $( !! 263 $(if $(strip $(any-prereq)),- due to: $(any-prereq), \
240 $(if $(cmd-check), !! 264 $(if $(arg-check), \
241 $(if $(savedcmd_$@),- due !! 265 $(if $(cmd_$@),- due to command line change, \
242 $(if $(filter $@, $(ta 266 $(if $(filter $@, $(targets)), \
243 - due to missing . 267 - due to missing .cmd file, \
244 - due to $(notdir 268 - due to $(notdir $@) not in $$(targets) \
245 ) 269 ) \
246 ) 270 ) \
247 ) 271 ) \
248 ), 272 ), \
249 - due to target missing 273 - due to target missing \
250 ) 274 ) \
251 ) 275 )
252 276
253 why = $(space)$(strip $(_why)) !! 277 echo-why = $(call escsq, $(strip $(why)))
254 endif <<
255 <<
256 ############################################## <<
257 <<
258 # delete partially updated (i.e. corrupted) fi <<
259 .DELETE_ON_ERROR: <<
260 <<
261 # do not delete intermediate files automatical <<
262 # <<
263 # .NOTINTERMEDIATE is more correct, but only a <<
264 # Make 4.4 introduced .NOTINTERMEDIATE, and it <<
265 # global .NOTINTERMEDIATE does not work. We ca <<
266 # Use .SECONDARY for older Make versions, but <<
267 # deleted files. <<
268 ifneq ($(and $(filter notintermediate, $(.FEAT <<
269 .NOTINTERMEDIATE: <<
270 else <<
271 .SECONDARY: <<
272 endif 278 endif
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