1 # SPDX-License-Identifier: GPL-2.0 1 # SPDX-License-Identifier: GPL-2.0
2 #### 2 ####
3 # kbuild: Generic definitions 3 # kbuild: Generic definitions
4 4
5 # Convenient variables 5 # Convenient variables
6 comma := , 6 comma := ,
7 quote := " 7 quote := "
8 squote := ' 8 squote := '
9 empty := 9 empty :=
10 space := $(empty) $(empty) 10 space := $(empty) $(empty)
11 space_escape := _-_SPACE_-_ 11 space_escape := _-_SPACE_-_
12 pound := \# 12 pound := \#
13 define newline 13 define newline
14 14
15 15
16 endef 16 endef
17 17
18 ### 18 ###
19 # Comparison macros. 19 # Comparison macros.
20 # Usage: $(call test-lt, $(CONFIG_LLD_VERSION) 20 # Usage: $(call test-lt, $(CONFIG_LLD_VERSION), 150000)
21 # 21 #
22 # Use $(intcmp ...) if supported. (Make >= 4.4 22 # Use $(intcmp ...) if supported. (Make >= 4.4)
23 # Otherwise, fall back to the 'test' shell com 23 # Otherwise, fall back to the 'test' shell command.
24 ifeq ($(intcmp 1,0,,,y),y) 24 ifeq ($(intcmp 1,0,,,y),y)
25 test-ge = $(intcmp $(strip $1)0, $(strip $2)0, 25 test-ge = $(intcmp $(strip $1)0, $(strip $2)0,,y,y)
26 test-gt = $(intcmp $(strip $1)0, $(strip $2)0, 26 test-gt = $(intcmp $(strip $1)0, $(strip $2)0,,,y)
27 else 27 else
28 test-ge = $(shell test $(strip $1)0 -ge $(stri 28 test-ge = $(shell test $(strip $1)0 -ge $(strip $2)0 && echo y)
29 test-gt = $(shell test $(strip $1)0 -gt $(stri 29 test-gt = $(shell test $(strip $1)0 -gt $(strip $2)0 && echo y)
30 endif 30 endif
31 test-le = $(call test-ge, $2, $1) 31 test-le = $(call test-ge, $2, $1)
32 test-lt = $(call test-gt, $2, $1) 32 test-lt = $(call test-gt, $2, $1)
33 33
34 ### 34 ###
35 # Name of target with a '.' as filename prefix 35 # Name of target with a '.' as filename prefix. foo/bar.o => foo/.bar.o
36 dot-target = $(dir $@).$(notdir $@) 36 dot-target = $(dir $@).$(notdir $@)
37 37
38 ### 38 ###
39 # Name of target with a '.tmp_' as filename pr 39 # Name of target with a '.tmp_' as filename prefix. foo/bar.o => foo/.tmp_bar.o
40 tmp-target = $(dir $@).tmp_$(notdir $@) 40 tmp-target = $(dir $@).tmp_$(notdir $@)
41 41
42 ### 42 ###
43 # The temporary file to save gcc -MMD generate 43 # The temporary file to save gcc -MMD generated dependencies must not
44 # contain a comma 44 # contain a comma
45 depfile = $(subst $(comma),_,$(dot-target).d) 45 depfile = $(subst $(comma),_,$(dot-target).d)
46 46
47 ### 47 ###
48 # filename of target with directory and extens 48 # filename of target with directory and extension stripped
49 basetarget = $(basename $(notdir $@)) 49 basetarget = $(basename $(notdir $@))
50 50
51 ### 51 ###
52 # real prerequisites without phony targets 52 # real prerequisites without phony targets
53 real-prereqs = $(filter-out $(PHONY), $^) 53 real-prereqs = $(filter-out $(PHONY), $^)
54 54
55 ### 55 ###
56 # Escape single quote for use in echo statemen 56 # Escape single quote for use in echo statements
57 escsq = $(subst $(squote),'\$(squote)',$1) 57 escsq = $(subst $(squote),'\$(squote)',$1)
58 58
59 ### 59 ###
60 # Quote a string to pass it to C files. foo => 60 # Quote a string to pass it to C files. foo => '"foo"'
61 stringify = $(squote)$(quote)$1$(quote)$(squot 61 stringify = $(squote)$(quote)$1$(quote)$(squote)
62 62
63 ### 63 ###
64 # The path to Kbuild or Makefile. Kbuild has p 64 # The path to Kbuild or Makefile. Kbuild has precedence over Makefile.
65 kbuild-file = $(or $(wildcard $(src)/Kbuild),$ 65 kbuild-file = $(or $(wildcard $(src)/Kbuild),$(src)/Makefile)
66 66
67 ### 67 ###
68 # Read a file, replacing newlines with spaces 68 # Read a file, replacing newlines with spaces
69 # 69 #
70 # Make 4.2 or later can read a file by using i 70 # Make 4.2 or later can read a file by using its builtin function.
71 ifneq ($(filter-out 4.0 4.1, $(MAKE_VERSION)), 71 ifneq ($(filter-out 4.0 4.1, $(MAKE_VERSION)),)
72 read-file = $(subst $(newline),$(space),$(file 72 read-file = $(subst $(newline),$(space),$(file < $1))
73 else 73 else
74 read-file = $(shell cat $1 2>/dev/null) 74 read-file = $(shell cat $1 2>/dev/null)
75 endif 75 endif
76 76
77 ### 77 ###
78 # Easy method for doing a status message 78 # Easy method for doing a status message
79 kecho := : 79 kecho := :
80 quiet_kecho := echo 80 quiet_kecho := echo
81 silent_kecho := : 81 silent_kecho := :
82 kecho := $($(quiet)kecho) 82 kecho := $($(quiet)kecho)
83 83
84 ### 84 ###
85 # filechk is used to check if the content of a 85 # filechk is used to check if the content of a generated file is updated.
86 # Sample usage: 86 # Sample usage:
87 # 87 #
88 # filechk_sample = echo $(KERNELRELEASE) 88 # filechk_sample = echo $(KERNELRELEASE)
89 # version.h: FORCE 89 # version.h: FORCE
90 # $(call filechk,sample) 90 # $(call filechk,sample)
91 # 91 #
92 # The rule defined shall write to stdout the c 92 # The rule defined shall write to stdout the content of the new file.
93 # The existing file will be compared with the 93 # The existing file will be compared with the new one.
94 # - If no file exist it is created 94 # - If no file exist it is created
95 # - If the content differ the new file is used 95 # - If the content differ the new file is used
96 # - If they are equal no change, and no timest 96 # - If they are equal no change, and no timestamp update
97 define filechk 97 define filechk
98 $(check-FORCE) 98 $(check-FORCE)
99 $(Q)set -e; 99 $(Q)set -e; \
100 mkdir -p $(dir $@); 100 mkdir -p $(dir $@); \
101 trap "rm -f $(tmp-target)" EXIT; 101 trap "rm -f $(tmp-target)" EXIT; \
102 { $(filechk_$(1)); } > $(tmp-target); 102 { $(filechk_$(1)); } > $(tmp-target); \
103 if [ ! -r $@ ] || ! cmp -s $@ $(tmp-ta 103 if [ ! -r $@ ] || ! cmp -s $@ $(tmp-target); then \
104 $(kecho) ' UPD $@'; 104 $(kecho) ' UPD $@'; \
105 mv -f $(tmp-target) $@; 105 mv -f $(tmp-target) $@; \
106 fi 106 fi
107 endef 107 endef
108 108
109 ### 109 ###
110 # Shorthand for $(Q)$(MAKE) -f scripts/Makefil 110 # Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj=
111 # Usage: 111 # Usage:
112 # $(Q)$(MAKE) $(build)=dir 112 # $(Q)$(MAKE) $(build)=dir
113 build := -f $(srctree)/scripts/Makefile.build 113 build := -f $(srctree)/scripts/Makefile.build obj
114 114
115 ### 115 ###
116 # Shorthand for $(Q)$(MAKE) -f scripts/Makefil 116 # Shorthand for $(Q)$(MAKE) -f scripts/Makefile.clean obj=
117 # Usage: 117 # Usage:
118 # $(Q)$(MAKE) $(clean)=dir 118 # $(Q)$(MAKE) $(clean)=dir
119 clean := -f $(srctree)/scripts/Makefile.clean 119 clean := -f $(srctree)/scripts/Makefile.clean obj
120 120
121 # pring log 121 # pring log
122 # 122 #
123 # If quiet is "silent_", print nothing and sin 123 # If quiet is "silent_", print nothing and sink stdout
124 # If quiet is "quiet_", print short log 124 # If quiet is "quiet_", print short log
125 # If quiet is empty, print short log and whole 125 # If quiet is empty, print short log and whole command
126 silent_log_print = exec >/dev/null; 126 silent_log_print = exec >/dev/null;
127 quiet_log_print = $(if $(quiet_cmd_$1), echo 127 quiet_log_print = $(if $(quiet_cmd_$1), echo ' $(call escsq,$(quiet_cmd_$1)$(why))';)
128 log_print = echo '$(pound) $(call escsq 128 log_print = echo '$(pound) $(call escsq,$(or $(quiet_cmd_$1),cmd_$1 $@)$(why))'; \
129 echo ' $(call escsq,$(cmd_ 129 echo ' $(call escsq,$(cmd_$1))';
130 130
131 # Delete the target on interruption 131 # Delete the target on interruption
132 # 132 #
133 # GNU Make automatically deletes the target if 133 # GNU Make automatically deletes the target if it has already been changed by
134 # the interrupted recipe. So, you can safely s 134 # the interrupted recipe. So, you can safely stop the build by Ctrl-C (Make
135 # will delete incomplete targets), and resume 135 # will delete incomplete targets), and resume it later.
136 # 136 #
137 # However, this does not work when the stderr 137 # However, this does not work when the stderr is piped to another program, like
138 # $ make >&2 | tee log 138 # $ make >&2 | tee log
139 # Make dies with SIGPIPE before cleaning the t 139 # Make dies with SIGPIPE before cleaning the targets.
140 # 140 #
141 # To address it, we clean the target in signal 141 # To address it, we clean the target in signal traps.
142 # 142 #
143 # Make deletes the target when it catches SIGH 143 # Make deletes the target when it catches SIGHUP, SIGINT, SIGQUIT, SIGTERM.
144 # So, we cover them, and also SIGPIPE just in 144 # So, we cover them, and also SIGPIPE just in case.
145 # 145 #
146 # Of course, this is unneeded for phony target 146 # Of course, this is unneeded for phony targets.
147 delete-on-interrupt = \ 147 delete-on-interrupt = \
148 $(if $(filter-out $(PHONY), $@), \ 148 $(if $(filter-out $(PHONY), $@), \
149 $(foreach sig, HUP INT QUIT TE 149 $(foreach sig, HUP INT QUIT TERM PIPE, \
150 trap 'rm -f $@; trap - 150 trap 'rm -f $@; trap - $(sig); kill -s $(sig) $$$$' $(sig);))
151 151
152 # print and execute commands 152 # print and execute commands
153 cmd = @$(if $(cmd_$(1)),set -e; $($(quiet)log_ 153 cmd = @$(if $(cmd_$(1)),set -e; $($(quiet)log_print) $(delete-on-interrupt) $(cmd_$(1)),:)
154 154
155 ### 155 ###
156 # if_changed - execute command if any pre 156 # if_changed - execute command if any prerequisite is newer than
157 # target, or command line ha 157 # target, or command line has changed
158 # if_changed_dep - as if_changed, but uses fi 158 # if_changed_dep - as if_changed, but uses fixdep to reveal dependencies
159 # including used config symb 159 # including used config symbols
160 # if_changed_rule - as if_changed but execute 160 # if_changed_rule - as if_changed but execute rule instead
161 # See Documentation/kbuild/makefiles.rst for m 161 # See Documentation/kbuild/makefiles.rst for more info
162 162
163 ifneq ($(KBUILD_NOCMDDEP),1) 163 ifneq ($(KBUILD_NOCMDDEP),1)
164 # Check if both commands are the same includin 164 # Check if both commands are the same including their order. Result is empty
165 # string if equal. User may override this chec 165 # string if equal. User may override this check using make KBUILD_NOCMDDEP=1
166 # If the target does not exist, the *.cmd file 166 # If the target does not exist, the *.cmd file should not be included so
167 # $(savedcmd_$@) gets empty. Then, target will 167 # $(savedcmd_$@) gets empty. Then, target will be built even if $(newer-prereqs)
168 # happens to become empty. 168 # happens to become empty.
169 cmd-check = $(filter-out $(subst $(space),$(sp 169 cmd-check = $(filter-out $(subst $(space),$(space_escape),$(strip $(savedcmd_$@))), \
170 $(subst $(space),$(sp 170 $(subst $(space),$(space_escape),$(strip $(cmd_$1))))
171 else 171 else
172 # We still need to detect missing targets. 172 # We still need to detect missing targets.
173 cmd-check = $(if $(strip $(savedcmd_$@)),,1) 173 cmd-check = $(if $(strip $(savedcmd_$@)),,1)
174 endif 174 endif
175 175
176 # Replace >$< with >$$< to preserve $ when rel 176 # Replace >$< with >$$< to preserve $ when reloading the .cmd file
177 # (needed for make) 177 # (needed for make)
178 # Replace >#< with >$(pound)< to avoid startin 178 # Replace >#< with >$(pound)< to avoid starting a comment in the .cmd file
179 # (needed for make) 179 # (needed for make)
180 # Replace >'< with >'\''< to be able to enclos 180 # Replace >'< with >'\''< to be able to enclose the whole string in '...'
181 # (needed for the shell) 181 # (needed for the shell)
182 make-cmd = $(call escsq,$(subst $(pound),$$(po 182 make-cmd = $(call escsq,$(subst $(pound),$$(pound),$(subst $$,$$$$,$(cmd_$(1)))))
183 183
184 # Find any prerequisites that are newer than t 184 # Find any prerequisites that are newer than target or that do not exist.
185 # PHONY targets skipped in both cases. 185 # PHONY targets skipped in both cases.
186 # If there is no prerequisite other than phony 186 # If there is no prerequisite other than phony targets, $(newer-prereqs) becomes
187 # empty even if the target does not exist. cmd 187 # empty even if the target does not exist. cmd-check saves this corner case.
188 newer-prereqs = $(filter-out $(PHONY),$?) 188 newer-prereqs = $(filter-out $(PHONY),$?)
189 189
190 # It is a typical mistake to forget the FORCE 190 # It is a typical mistake to forget the FORCE prerequisite. Check it here so
191 # no more breakage will slip in. 191 # no more breakage will slip in.
192 check-FORCE = $(if $(filter FORCE, $^),,$(warn 192 check-FORCE = $(if $(filter FORCE, $^),,$(warning FORCE prerequisite is missing))
193 193
194 if-changed-cond = $(newer-prereqs)$(cmd-check) 194 if-changed-cond = $(newer-prereqs)$(cmd-check)$(check-FORCE)
195 195
196 # Execute command if command has changed or pr 196 # Execute command if command has changed or prerequisite(s) are updated.
197 if_changed = $(if $(if-changed-cond),$(cmd_and 197 if_changed = $(if $(if-changed-cond),$(cmd_and_savecmd),@:)
198 198
199 cmd_and_savecmd = 199 cmd_and_savecmd = \
200 $(cmd); 200 $(cmd); \
201 printf '%s\n' 'savedcmd_$@ := $(make-c 201 printf '%s\n' 'savedcmd_$@ := $(make-cmd)' > $(dot-target).cmd
202 202
203 # Execute the command and also postprocess gen 203 # Execute the command and also postprocess generated .d dependencies file.
204 if_changed_dep = $(if $(if-changed-cond),$(cmd 204 if_changed_dep = $(if $(if-changed-cond),$(cmd_and_fixdep),@:)
205 205
206 cmd_and_fixdep = 206 cmd_and_fixdep = \
207 $(cmd); 207 $(cmd); \
208 scripts/basic/fixdep $(depfile) $@ '$( 208 scripts/basic/fixdep $(depfile) $@ '$(make-cmd)' > $(dot-target).cmd;\
209 rm -f $(depfile) 209 rm -f $(depfile)
210 210
211 # Usage: $(call if_changed_rule,foo) 211 # Usage: $(call if_changed_rule,foo)
212 # Will check if $(cmd_foo) or any of the prere 212 # Will check if $(cmd_foo) or any of the prerequisites changed,
213 # and if so will execute $(rule_foo). 213 # and if so will execute $(rule_foo).
214 if_changed_rule = $(if $(if-changed-cond),$(ru 214 if_changed_rule = $(if $(if-changed-cond),$(rule_$(1)),@:)
215 215
216 ### 216 ###
217 # why - tell why a target got built 217 # why - tell why a target got built
218 # enabled by make V=2 218 # enabled by make V=2
219 # Output (listed in the order they are c 219 # Output (listed in the order they are checked):
220 # (1) - due to target is PHONY 220 # (1) - due to target is PHONY
221 # (2) - due to target missing 221 # (2) - due to target missing
222 # (3) - due to: file1.h file2.h 222 # (3) - due to: file1.h file2.h
223 # (4) - due to command line change 223 # (4) - due to command line change
224 # (5) - due to missing .cmd file 224 # (5) - due to missing .cmd file
225 # (6) - due to target not in $(target 225 # (6) - due to target not in $(targets)
226 # (1) PHONY targets are always build 226 # (1) PHONY targets are always build
227 # (2) No target, so we better build it 227 # (2) No target, so we better build it
228 # (3) Prerequisite is newer than target 228 # (3) Prerequisite is newer than target
229 # (4) The command line stored in the file name 229 # (4) The command line stored in the file named dir/.target.cmd
230 # differed from actual command line. This 230 # differed from actual command line. This happens when compiler
231 # options changes 231 # options changes
232 # (5) No dir/.target.cmd file (used to store c 232 # (5) No dir/.target.cmd file (used to store command line)
233 # (6) No dir/.target.cmd file and target not l 233 # (6) No dir/.target.cmd file and target not listed in $(targets)
234 # This is a good hint that there is a bug 234 # This is a good hint that there is a bug in the kbuild file
235 ifneq ($(findstring 2, $(KBUILD_VERBOSE)),) 235 ifneq ($(findstring 2, $(KBUILD_VERBOSE)),)
236 _why = 236 _why = \
237 $(if $(filter $@, $(PHONY)),- due to targe 237 $(if $(filter $@, $(PHONY)),- due to target is PHONY, \
238 $(if $(wildcard $@), 238 $(if $(wildcard $@), \
239 $(if $(newer-prereqs),- due to: $( 239 $(if $(newer-prereqs),- due to: $(newer-prereqs), \
240 $(if $(cmd-check), 240 $(if $(cmd-check), \
241 $(if $(savedcmd_$@),- due 241 $(if $(savedcmd_$@),- due to command line change, \
242 $(if $(filter $@, $(ta 242 $(if $(filter $@, $(targets)), \
243 - due to missing . 243 - due to missing .cmd file, \
244 - due to $(notdir 244 - due to $(notdir $@) not in $$(targets) \
245 ) 245 ) \
246 ) 246 ) \
247 ) 247 ) \
248 ), 248 ), \
249 - due to target missing 249 - due to target missing \
250 ) 250 ) \
251 ) 251 )
252 252
253 why = $(space)$(strip $(_why)) 253 why = $(space)$(strip $(_why))
254 endif 254 endif
255 255
256 ############################################## 256 ###############################################################################
257 257
258 # delete partially updated (i.e. corrupted) fi 258 # delete partially updated (i.e. corrupted) files on error
259 .DELETE_ON_ERROR: 259 .DELETE_ON_ERROR:
260 260
261 # do not delete intermediate files automatical 261 # do not delete intermediate files automatically
262 # 262 #
263 # .NOTINTERMEDIATE is more correct, but only a 263 # .NOTINTERMEDIATE is more correct, but only available on newer Make versions.
264 # Make 4.4 introduced .NOTINTERMEDIATE, and it 264 # Make 4.4 introduced .NOTINTERMEDIATE, and it appears in .FEATURES, but the
265 # global .NOTINTERMEDIATE does not work. We ca 265 # global .NOTINTERMEDIATE does not work. We can use it on Make > 4.4.
266 # Use .SECONDARY for older Make versions, but 266 # Use .SECONDARY for older Make versions, but "newer-prereq" cannot detect
267 # deleted files. 267 # deleted files.
268 ifneq ($(and $(filter notintermediate, $(.FEAT 268 ifneq ($(and $(filter notintermediate, $(.FEATURES)),$(filter-out 4.4,$(MAKE_VERSION))),)
269 .NOTINTERMEDIATE: 269 .NOTINTERMEDIATE:
270 else 270 else
271 .SECONDARY: 271 .SECONDARY:
272 endif 272 endif
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.