GNU Linux-libre 4.4.284-gnu1
[releases.git] / scripts / Makefile.build
1 # ==========================================================================
2 # Building
3 # ==========================================================================
4
5 src := $(obj)
6
7 PHONY := __build
8 __build:
9
10 # Init all relevant variables used in kbuild files so
11 # 1) they have correct type
12 # 2) they do not inherit any value from the environment
13 obj-y :=
14 obj-m :=
15 lib-y :=
16 lib-m :=
17 always :=
18 targets :=
19 subdir-y :=
20 subdir-m :=
21 EXTRA_AFLAGS   :=
22 EXTRA_CFLAGS   :=
23 EXTRA_CPPFLAGS :=
24 EXTRA_LDFLAGS  :=
25 asflags-y  :=
26 ccflags-y  :=
27 cppflags-y :=
28 ldflags-y  :=
29
30 subdir-asflags-y :=
31 subdir-ccflags-y :=
32
33 # Read auto.conf if it exists, otherwise ignore
34 -include include/config/auto.conf
35
36 include scripts/Kbuild.include
37
38 # For backward compatibility check that these variables do not change
39 save-cflags := $(CFLAGS)
40
41 # The filename Kbuild has precedence over Makefile
42 kbuild-dir := $(if $(filter /%,$(src)),$(src),$(srctree)/$(src))
43 kbuild-file := $(if $(wildcard $(kbuild-dir)/Kbuild),$(kbuild-dir)/Kbuild,$(kbuild-dir)/Makefile)
44 include $(kbuild-file)
45
46 # If the save-* variables changed error out
47 ifeq ($(KBUILD_NOPEDANTIC),)
48         ifneq ("$(save-cflags)","$(CFLAGS)")
49                 $(error CFLAGS was changed in "$(kbuild-file)". Fix it to use ccflags-y)
50         endif
51 endif
52
53 include scripts/Makefile.lib
54
55 ifdef host-progs
56 ifneq ($(hostprogs-y),$(host-progs))
57 $(warning kbuild: $(obj)/Makefile - Usage of host-progs is deprecated. Please replace with hostprogs-y!)
58 hostprogs-y += $(host-progs)
59 endif
60 endif
61
62 # Do not include host rules unless needed
63 ifneq ($(hostprogs-y)$(hostprogs-m),)
64 include scripts/Makefile.host
65 endif
66
67 ifneq ($(KBUILD_SRC),)
68 # Create output directory if not already present
69 _dummy := $(shell [ -d $(obj) ] || mkdir -p $(obj))
70
71 # Create directories for object files if directory does not exist
72 # Needed when obj-y := dir/file.o syntax is used
73 _dummy := $(foreach d,$(obj-dirs), $(shell [ -d $(d) ] || mkdir -p $(d)))
74 endif
75
76 ifndef obj
77 $(warning kbuild: Makefile.build is included improperly)
78 endif
79
80 # ===========================================================================
81
82 ifneq ($(strip $(lib-y) $(lib-m) $(lib-)),)
83 lib-target := $(obj)/lib.a
84 endif
85
86 ifneq ($(strip $(obj-y) $(obj-m) $(obj-) $(subdir-m) $(lib-target)),)
87 builtin-target := $(obj)/built-in.o
88 endif
89
90 modorder-target := $(obj)/modules.order
91
92 # We keep a list of all modules in $(MODVERDIR)
93
94 __build: $(if $(KBUILD_BUILTIN),$(builtin-target) $(lib-target) $(extra-y)) \
95          $(if $(KBUILD_MODULES),$(obj-m) $(modorder-target)) \
96          $(subdir-ym) $(always)
97         @:
98
99 # Linus' kernel sanity checking tool
100 ifneq ($(KBUILD_CHECKSRC),0)
101   ifeq ($(KBUILD_CHECKSRC),2)
102     quiet_cmd_force_checksrc = CHECK   $<
103           cmd_force_checksrc = $(CHECK) $(CHECKFLAGS) $(c_flags) $< ;
104   else
105       quiet_cmd_checksrc     = CHECK   $<
106             cmd_checksrc     = $(CHECK) $(CHECKFLAGS) $(c_flags) $< ;
107   endif
108 endif
109
110 # Do section mismatch analysis for each module/built-in.o
111 ifdef CONFIG_DEBUG_SECTION_MISMATCH
112   cmd_secanalysis = ; scripts/mod/modpost $@
113 endif
114
115 # Compile C sources (.c)
116 # ---------------------------------------------------------------------------
117
118 # Default is built-in, unless we know otherwise
119 modkern_cflags =                                          \
120         $(if $(part-of-module),                           \
121                 $(KBUILD_CFLAGS_MODULE) $(CFLAGS_MODULE), \
122                 $(KBUILD_CFLAGS_KERNEL) $(CFLAGS_KERNEL))
123 quiet_modtag := $(empty)   $(empty)
124
125 $(real-objs-m)        : part-of-module := y
126 $(real-objs-m:.o=.i)  : part-of-module := y
127 $(real-objs-m:.o=.s)  : part-of-module := y
128 $(real-objs-m:.o=.lst): part-of-module := y
129
130 $(real-objs-m)        : quiet_modtag := [M]
131 $(real-objs-m:.o=.i)  : quiet_modtag := [M]
132 $(real-objs-m:.o=.s)  : quiet_modtag := [M]
133 $(real-objs-m:.o=.lst): quiet_modtag := [M]
134
135 $(obj-m)              : quiet_modtag := [M]
136
137 # Default for not multi-part modules
138 modname = $(basetarget)
139
140 $(multi-objs-m)         : modname = $(modname-multi)
141 $(multi-objs-m:.o=.i)   : modname = $(modname-multi)
142 $(multi-objs-m:.o=.s)   : modname = $(modname-multi)
143 $(multi-objs-m:.o=.lst) : modname = $(modname-multi)
144 $(multi-objs-y)         : modname = $(modname-multi)
145 $(multi-objs-y:.o=.i)   : modname = $(modname-multi)
146 $(multi-objs-y:.o=.s)   : modname = $(modname-multi)
147 $(multi-objs-y:.o=.lst) : modname = $(modname-multi)
148
149 quiet_cmd_cc_s_c = CC $(quiet_modtag)  $@
150 cmd_cc_s_c       = $(CC) $(c_flags) $(DISABLE_LTO) -fverbose-asm -S -o $@ $<
151
152 $(obj)/%.s: $(src)/%.c FORCE
153         $(call if_changed_dep,cc_s_c)
154
155 quiet_cmd_cc_i_c = CPP $(quiet_modtag) $@
156 cmd_cc_i_c       = $(CPP) $(c_flags)   -o $@ $<
157
158 $(obj)/%.i: $(src)/%.c FORCE
159         $(call if_changed_dep,cc_i_c)
160
161 # These mirror gensymtypes_S and co below, keep them in synch.
162 cmd_gensymtypes_c =                                                         \
163     $(CPP) -D__GENKSYMS__ $(c_flags) $< |                                   \
164     $(GENKSYMS) $(if $(1), -T $(2))                                         \
165      $(patsubst y,-s _,$(CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX))             \
166      $(if $(KBUILD_PRESERVE),-p)                                            \
167      -r $(firstword $(wildcard $(2:.symtypes=.symref) /dev/null))
168
169 quiet_cmd_cc_symtypes_c = SYM $(quiet_modtag) $@
170 cmd_cc_symtypes_c =                                                         \
171     set -e;                                                                 \
172     $(call cmd_gensymtypes_c,true,$@) >/dev/null;                           \
173     test -s $@ || rm -f $@
174
175 $(obj)/%.symtypes : $(src)/%.c FORCE
176         $(call cmd,cc_symtypes_c)
177
178 # LLVM assembly
179 # Generate .ll files from .c
180 quiet_cmd_cc_ll_c = CC $(quiet_modtag)  $@
181       cmd_cc_ll_c = $(CC) $(c_flags) -emit-llvm -S -o $@ $<
182
183 $(obj)/%.ll: $(src)/%.c FORCE
184         $(call if_changed_dep,cc_ll_c)
185
186 # C (.c) files
187 # The C file is compiled and updated dependency information is generated.
188 # (See cmd_cc_o_c + relevant part of rule_cc_o_c)
189
190 quiet_cmd_cc_o_c = CC $(quiet_modtag)  $@
191
192 ifndef CONFIG_MODVERSIONS
193 cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
194
195 else
196 # When module versioning is enabled the following steps are executed:
197 # o compile a .tmp_<file>.o from <file>.c
198 # o if .tmp_<file>.o doesn't contain a __ksymtab version, i.e. does
199 #   not export symbols, we just rename .tmp_<file>.o to <file>.o and
200 #   are done.
201 # o otherwise, we calculate symbol versions using the good old
202 #   genksyms on the preprocessed source and postprocess them in a way
203 #   that they are usable as a linker script
204 # o generate <file>.o from .tmp_<file>.o using the linker to
205 #   replace the unresolved symbols __crc_exported_symbol with
206 #   the actual value of the checksum generated by genksyms
207
208 cmd_cc_o_c = $(CC) $(c_flags) -c -o $(@D)/.tmp_$(@F) $<
209
210 cmd_modversions_c =                                                             \
211         if $(OBJDUMP) -h $(@D)/.tmp_$(@F) | grep -q __ksymtab; then             \
212                 $(call cmd_gensymtypes_c,$(KBUILD_SYMTYPES),$(@:.o=.symtypes))  \
213                     > $(@D)/.tmp_$(@F:.o=.ver);                                 \
214                                                                                 \
215                 $(LD) $(LDFLAGS) -r -o $@ $(@D)/.tmp_$(@F)                      \
216                         -T $(@D)/.tmp_$(@F:.o=.ver);                            \
217                 rm -f $(@D)/.tmp_$(@F) $(@D)/.tmp_$(@F:.o=.ver);                \
218         else                                                                    \
219                 mv -f $(@D)/.tmp_$(@F) $@;                                      \
220         fi;
221 endif
222
223 ifdef CONFIG_FTRACE_MCOUNT_RECORD
224 ifndef CC_USING_RECORD_MCOUNT
225 # compiler will not generate __mcount_loc use recordmcount or recordmcount.pl
226 ifdef BUILD_C_RECORDMCOUNT
227 ifeq ("$(origin RECORDMCOUNT_WARN)", "command line")
228   RECORDMCOUNT_FLAGS = -w
229 endif
230 # Due to recursion, we must skip empty.o.
231 # The empty.o file is created in the make process in order to determine
232 #  the target endianness and word size. It is made before all other C
233 #  files, including recordmcount.
234 sub_cmd_record_mcount =                                 \
235         if [ $(@) != "scripts/mod/empty.o" ]; then      \
236                 $(objtree)/scripts/recordmcount $(RECORDMCOUNT_FLAGS) "$(@)";   \
237         fi;
238 recordmcount_source := $(srctree)/scripts/recordmcount.c \
239                     $(srctree)/scripts/recordmcount.h
240 else
241 sub_cmd_record_mcount = set -e ; perl $(srctree)/scripts/recordmcount.pl "$(ARCH)" \
242         "$(if $(CONFIG_CPU_BIG_ENDIAN),big,little)" \
243         "$(if $(CONFIG_64BIT),64,32)" \
244         "$(OBJDUMP)" "$(OBJCOPY)" "$(CC) $(KBUILD_CFLAGS)" \
245         "$(LD)" "$(NM)" "$(RM)" "$(MV)" \
246         "$(if $(part-of-module),1,0)" "$(@)";
247 recordmcount_source := $(srctree)/scripts/recordmcount.pl
248 endif
249 cmd_record_mcount =                                             \
250         if [ "$(findstring $(CC_FLAGS_FTRACE),$(_c_flags))" =   \
251              "$(CC_FLAGS_FTRACE)" ]; then                       \
252                 $(sub_cmd_record_mcount)                        \
253         fi;
254 endif # CC_USING_RECORD_MCOUNT
255 endif
256
257 define rule_cc_o_c
258         $(call echo-cmd,checksrc) $(cmd_checksrc)                         \
259         $(call echo-cmd,cc_o_c) $(cmd_cc_o_c);                            \
260         $(cmd_modversions_c)                                              \
261         $(call echo-cmd,record_mcount)                                    \
262         $(cmd_record_mcount)                                              \
263         scripts/basic/fixdep $(depfile) $@ '$(call make-cmd,cc_o_c)' >    \
264                                                       $(dot-target).tmp;  \
265         rm -f $(depfile);                                                 \
266         mv -f $(dot-target).tmp $(dot-target).cmd
267 endef
268
269 define rule_as_o_S
270        $(call echo-cmd,as_o_S) $(cmd_as_o_S);                            \
271        scripts/basic/fixdep $(depfile) $@ '$(call make-cmd,as_o_S)' >    \
272                                                      $(dot-target).tmp;  \
273        $(cmd_modversions_S)                                              \
274        rm -f $(depfile);                                                 \
275        mv -f $(dot-target).tmp $(dot-target).cmd
276 endef
277
278 # Built-in and composite module parts
279 $(obj)/%.o: $(src)/%.c $(recordmcount_source) FORCE
280         $(call cmd,force_checksrc)
281         $(call if_changed_rule,cc_o_c)
282
283 # Single-part modules are special since we need to mark them in $(MODVERDIR)
284
285 $(single-used-m): $(obj)/%.o: $(src)/%.c $(recordmcount_source) FORCE
286         $(call cmd,force_checksrc)
287         $(call if_changed_rule,cc_o_c)
288         @{ echo $(@:.o=.ko); echo $@; } > $(MODVERDIR)/$(@F:.o=.mod)
289
290 quiet_cmd_cc_lst_c = MKLST   $@
291       cmd_cc_lst_c = $(CC) $(c_flags) -g -c -o $*.o $< && \
292                      $(CONFIG_SHELL) $(srctree)/scripts/makelst $*.o \
293                                      System.map $(OBJDUMP) > $@
294
295 $(obj)/%.lst: $(src)/%.c FORCE
296         $(call if_changed_dep,cc_lst_c)
297
298 # Compile assembler sources (.S)
299 # ---------------------------------------------------------------------------
300
301 modkern_aflags := $(KBUILD_AFLAGS_KERNEL) $(AFLAGS_KERNEL)
302
303 $(real-objs-m)      : modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE)
304 $(real-objs-m:.o=.s): modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE)
305
306 # .S file exports must have their C prototypes defined in asm/asm-prototypes.h
307 # or a file that it includes, in order to get versioned symbols. We build a
308 # dummy C file that includes asm-prototypes and the EXPORT_SYMBOL lines from
309 # the .S file (with trailing ';'), and run genksyms on that, to extract vers.
310 #
311 # This is convoluted. The .S file must first be preprocessed to run guards and
312 # expand names, then the resulting exports must be constructed into plain
313 # EXPORT_SYMBOL(symbol); to build our dummy C file, and that gets preprocessed
314 # to make the genksyms input.
315 #
316 # These mirror gensymtypes_c and co above, keep them in synch.
317 cmd_gensymtypes_S =                                                         \
318     (echo "\#include <linux/kernel.h>" ;                                    \
319      echo "\#include <asm/asm-prototypes.h>" ;                              \
320     $(CPP) $(a_flags) $< |                                                  \
321       grep "\<___EXPORT_SYMBOL\>" |                                          \
322       sed 's/.*___EXPORT_SYMBOL[[:space:]]*\([a-zA-Z0-9_]*\)[[:space:]]*,.*/EXPORT_SYMBOL(\1);/' ) | \
323     $(CPP) -D__GENKSYMS__ $(c_flags) -xc - |                                \
324     $(GENKSYMS) $(if $(1), -T $(2))                                         \
325      $(patsubst y,-s _,$(CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX))             \
326      $(if $(KBUILD_PRESERVE),-p)                                            \
327      -r $(firstword $(wildcard $(2:.symtypes=.symref) /dev/null))
328
329 quiet_cmd_cc_symtypes_S = SYM $(quiet_modtag) $@
330 cmd_cc_symtypes_S =                                                         \
331     set -e;                                                                 \
332     $(call cmd_gensymtypes_S,true,$@) >/dev/null;                           \
333     test -s $@ || rm -f $@
334
335 $(obj)/%.symtypes : $(src)/%.S FORCE
336         $(call cmd,cc_symtypes_S)
337
338 quiet_cmd_as_s_S = CPP $(quiet_modtag) $@
339 cmd_as_s_S       = $(CPP) $(a_flags)   -o $@ $<
340
341 $(obj)/%.s: $(src)/%.S FORCE
342         $(call if_changed_dep,as_s_S)
343
344 quiet_cmd_as_o_S = AS $(quiet_modtag)  $@
345
346 ifndef CONFIG_MODVERSIONS
347 cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $<
348
349 else
350
351 ASM_PROTOTYPES := $(wildcard $(srctree)/arch/$(SRCARCH)/include/asm/asm-prototypes.h)
352
353 ifeq ($(ASM_PROTOTYPES),)
354 cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $<
355
356 else
357
358 # versioning matches the C process described above, with difference that
359 # we parse asm-prototypes.h C header to get function definitions.
360
361 cmd_as_o_S = $(CC) $(a_flags) -c -o $(@D)/.tmp_$(@F) $<
362
363 cmd_modversions_S =                                                             \
364         if $(OBJDUMP) -h $(@D)/.tmp_$(@F) | grep -q __ksymtab; then             \
365                 $(call cmd_gensymtypes_S,$(KBUILD_SYMTYPES),$(@:.o=.symtypes))  \
366                     > $(@D)/.tmp_$(@F:.o=.ver);                                 \
367                                                                                 \
368                 $(LD) $(LDFLAGS) -r -o $@ $(@D)/.tmp_$(@F)                      \
369                         -T $(@D)/.tmp_$(@F:.o=.ver);                            \
370                 rm -f $(@D)/.tmp_$(@F) $(@D)/.tmp_$(@F:.o=.ver);                \
371         else                                                                    \
372                 mv -f $(@D)/.tmp_$(@F) $@;                                      \
373         fi;
374 endif
375 endif
376
377 $(obj)/%.o: $(src)/%.S FORCE
378         $(call if_changed_rule,as_o_S)
379
380 targets += $(real-objs-y) $(real-objs-m) $(lib-y)
381 targets += $(extra-y) $(MAKECMDGOALS) $(always)
382
383 # Linker scripts preprocessor (.lds.S -> .lds)
384 # ---------------------------------------------------------------------------
385 quiet_cmd_cpp_lds_S = LDS     $@
386       cmd_cpp_lds_S = $(CPP) $(cpp_flags) -P -C -U$(ARCH) \
387                              -D__ASSEMBLY__ -DLINKER_SCRIPT -o $@ $<
388
389 $(obj)/%.lds: $(src)/%.lds.S FORCE
390         $(call if_changed_dep,cpp_lds_S)
391
392 # ASN.1 grammar
393 # ---------------------------------------------------------------------------
394 quiet_cmd_asn1_compiler = ASN.1   $@
395       cmd_asn1_compiler = $(objtree)/scripts/asn1_compiler $< \
396                                 $(subst .h,.c,$@) $(subst .c,.h,$@)
397
398 .PRECIOUS: $(objtree)/$(obj)/%-asn1.c $(objtree)/$(obj)/%-asn1.h
399
400 $(obj)/%-asn1.c $(obj)/%-asn1.h: $(src)/%.asn1 $(objtree)/scripts/asn1_compiler
401         $(call cmd,asn1_compiler)
402
403 # Build the compiled-in targets
404 # ---------------------------------------------------------------------------
405
406 # To build objects in subdirs, we need to descend into the directories
407 $(sort $(subdir-obj-y)): $(subdir-ym) ;
408
409 #
410 # Rule to compile a set of .o files into one .o file
411 #
412 ifdef builtin-target
413 quiet_cmd_link_o_target = LD      $@
414 # If the list of objects to link is empty, just create an empty built-in.o
415 cmd_link_o_target = $(if $(strip $(obj-y)),\
416                       $(LD) $(ld_flags) -r -o $@ $(filter $(obj-y), $^) \
417                       $(cmd_secanalysis),\
418                       rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS) $@)
419
420 $(builtin-target): $(obj-y) FORCE
421         $(call if_changed,link_o_target)
422
423 targets += $(builtin-target)
424 endif # builtin-target
425
426 #
427 # Rule to create modules.order file
428 #
429 # Create commands to either record .ko file or cat modules.order from
430 # a subdirectory
431 modorder-cmds =                                         \
432         $(foreach m, $(modorder),                       \
433                 $(if $(filter %/modules.order, $m),     \
434                         cat $m;, echo kernel/$m;))
435
436 $(modorder-target): $(subdir-ym) FORCE
437         $(Q)(cat /dev/null; $(modorder-cmds)) > $@
438
439 #
440 # Rule to compile a set of .o files into one .a file
441 #
442 ifdef lib-target
443 quiet_cmd_link_l_target = AR      $@
444 cmd_link_l_target = rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS) $@ $(lib-y)
445
446 $(lib-target): $(lib-y) FORCE
447         $(call if_changed,link_l_target)
448
449 targets += $(lib-target)
450 endif
451
452 #
453 # Rule to link composite objects
454 #
455 #  Composite objects are specified in kbuild makefile as follows:
456 #    <composite-object>-objs := <list of .o files>
457 #  or
458 #    <composite-object>-y    := <list of .o files>
459 link_multi_deps =                     \
460 $(filter $(addprefix $(obj)/,         \
461 $($(subst $(obj)/,,$(@:.o=-objs)))    \
462 $($(subst $(obj)/,,$(@:.o=-y)))), $^)
463
464 quiet_cmd_link_multi-y = LD      $@
465 cmd_link_multi-y = $(LD) $(ld_flags) -r -o $@ $(link_multi_deps) $(cmd_secanalysis)
466
467 quiet_cmd_link_multi-m = LD [M]  $@
468 cmd_link_multi-m = $(cmd_link_multi-y)
469
470 $(multi-used-y): FORCE
471         $(call if_changed,link_multi-y)
472 $(call multi_depend, $(multi-used-y), .o, -objs -y)
473
474 $(multi-used-m): FORCE
475         $(call if_changed,link_multi-m)
476         @{ echo $(@:.o=.ko); echo $(link_multi_deps); } > $(MODVERDIR)/$(@F:.o=.mod)
477 $(call multi_depend, $(multi-used-m), .o, -objs -y)
478
479 targets += $(multi-used-y) $(multi-used-m)
480
481
482 # Descending
483 # ---------------------------------------------------------------------------
484
485 PHONY += $(subdir-ym)
486 $(subdir-ym):
487         $(Q)$(MAKE) $(build)=$@
488
489 # Add FORCE to the prequisites of a target to force it to be always rebuilt.
490 # ---------------------------------------------------------------------------
491
492 PHONY += FORCE
493
494 FORCE:
495
496 # Read all saved command lines and dependencies for the $(targets) we
497 # may be building above, using $(if_changed{,_dep}). As an
498 # optimization, we don't need to read them if the target does not
499 # exist, we will rebuild anyway in that case.
500
501 targets := $(wildcard $(sort $(targets)))
502 cmd_files := $(wildcard $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd))
503
504 ifneq ($(cmd_files),)
505   include $(cmd_files)
506 endif
507
508 # Declare the contents of the .PHONY variable as phony.  We keep that
509 # information in a variable se we can use it in if_changed and friends.
510
511 .PHONY: $(PHONY)