Rules.make

   1 #
   2 # This file contains rules which are shared between multiple Makefiles.
   3 #
   4
   5 #
   6 # False targets.
   7 #
   8 .PHONY: dummy
   9
  10 #
  11 # Special variables which should not be exported
  12 #
  13 unexport EXTRA_ASFLAGS
  14 unexport EXTRA_CFLAGS
  15 unexport EXTRA_LDFLAGS
  16 unexport EXTRA_ARFLAGS
  17 unexport SUBDIRS
  18 unexport SUB_DIRS
  19 unexport ALL_SUB_DIRS
  20 unexport MOD_SUB_DIRS
  21 unexport O_TARGET
  22 unexport O_OBJS
  23 unexport L_OBJS
  24 unexport M_OBJS
  25 # intermediate objects that form part of a module
  26 unexport MI_OBJS
  27 unexport ALL_MOBJS
  28 # objects that export symbol tables
  29 unexport OX_OBJS
  30 unexport LX_OBJS
  31 unexport MX_OBJS
  32 unexport MIX_OBJS
  33 unexport SYMTAB_OBJS
  34
  35 #
  36 # Get things started.
  37 #
  38 first_rule: sub_dirs
  39         $(MAKE) all_targets
  40
  41 #
  42 # Common rules
  43 #
  44
  45 %.s: %.c
  46         $(CC) $(CFLAGS) $(EXTRA_CFLAGS) $(CFLAGS_$@) -S $< -o $@
  47
  48 %.i: %.c
  49         $(CPP) $(CFLAGS) $(EXTRA_CFLAGS) $(CFLAGS_$@) $< > $@
  50
  51 %.o: %.c
  52         $(CC) $(CFLAGS) $(EXTRA_CFLAGS) $(CFLAGS_$@) -c -o $@ $<
  53         @ ( \
  54             echo 'ifeq ($(strip $(subst $(comma),:,$(CFLAGS) $(EXTRA_CFLAGS) $(CFLAGS_$@))),$$(strip $$(subst $$(comma),:,$$(CFLAGS) $$(EXTRA_CFLAGS) $$(CFLAGS_$@))))' ; \
  55             echo 'FILES_FLAGS_UP_TO_DATE += $@' ; \
  56             echo 'endif' \
  57         ) > $(dir $@)/.$(notdir $@).flags
  58
  59 %.o: %.s
  60         $(AS) $(ASFLAGS) $(EXTRA_CFLAGS) -o $@ $<
  61
  62 #
  63 #
  64 #
  65 all_targets: $(O_TARGET) $(L_TARGET)
  66
  67 #
  68 # Rule to compile a set of .o files into one .o file
  69 #
  70 ifdef O_TARGET
  71 ALL_O = $(OX_OBJS) $(O_OBJS)
  72 $(O_TARGET): $(ALL_O)
  73         rm -f $@
  74     ifneq "$(strip $(ALL_O))" ""
  75         $(LD) $(EXTRA_LDFLAGS) -r -o $@ $(filter $(ALL_O), $^)
  76     else
  77         $(AR) rcs $@ $(filter $(ALL_O), $^)
  78     endif
  79         @ ( \
  80             echo 'ifeq ($(strip $(subst $(comma),:,$(EXTRA_LDFLAGS) $(ALL_O))),$$(strip $$(subst $$(comma),:,$$(EXTRA_LDFLAGS) $$(ALL_O))))' ; \
  81             echo 'FILES_FLAGS_UP_TO_DATE += $@' ; \
  82             echo 'endif' \
  83         ) > $(dir $@)/.$(notdir $@).flags
  84 endif # O_TARGET
  85
  86 #
  87 # Rule to compile a set of .o files into one .a file
  88 #
  89 ifdef L_TARGET
  90 $(L_TARGET): $(LX_OBJS) $(L_OBJS)
  91         rm -f $@
  92         $(AR) $(EXTRA_ARFLAGS) rcs $@ $(LX_OBJS) $(L_OBJS)
  93         @ ( \
  94             echo 'ifeq ($(strip $(subst $(comma),:,$(EXTRA_ARFLAGS) $(LX_OBJS) $(L_OBJS))),$$(strip $$(subst $$(comma),:,$$(EXTRA_ARFLAGS) $$(LX_OBJS) $$(L_OBJS))))' ; \
  95             echo 'FILES_FLAGS_UP_TO_DATE += $@' ; \
  96             echo 'endif' \
  97         ) > $(dir $@)/.$(notdir $@).flags
  98 endif
  99
 100 #
 101 # This make dependencies quickly
 102 #
 103 fastdep: dummy
 104         $(TOPDIR)/scripts/mkdep $(wildcard *.[chS] local.h.master) > .depend
 105 ifdef ALL_SUB_DIRS
 106         $(MAKE) $(patsubst %,_sfdep_%,$(ALL_SUB_DIRS)) _FASTDEP_ALL_SUB_DIRS="$(ALL_SUB_DIRS)"
 107 endif
 108
 109 ifdef _FASTDEP_ALL_SUB_DIRS
 110 $(patsubst %,_sfdep_%,$(_FASTDEP_ALL_SUB_DIRS)):
 111         $(MAKE) -C $(patsubst _sfdep_%,%,$@) fastdep
 112 endif
 113
 114
 115 #
 116 # A rule to make subdirectories
 117 #
 118 sub_dirs: dummy $(patsubst %,_subdir_%,$(SUB_DIRS))
 119
 120 ifdef SUB_DIRS
 121 $(patsubst %,_subdir_%,$(SUB_DIRS)) : dummy
 122         $(MAKE) -C $(patsubst _subdir_%,%,$@)
 123 endif
 124
 125 #
 126 # A rule to make modules
 127 #
 128 ALL_MOBJS = $(MX_OBJS) $(M_OBJS)
 129 ifneq "$(strip $(ALL_MOBJS))" ""
 130 PDWN=$(shell $(CONFIG_SHELL) $(TOPDIR)/scripts/pathdown.sh)
 131 endif
 132
 133 unexport MOD_DIRS
 134 MOD_DIRS := $(MOD_SUB_DIRS) $(MOD_IN_SUB_DIRS)
 135 ifneq "$(strip $(MOD_DIRS))" ""
 136 .PHONY: $(patsubst %,_modsubdir_%,$(MOD_DIRS))
 137 $(patsubst %,_modsubdir_%,$(MOD_DIRS)) : dummy
 138         $(MAKE) -C $(patsubst _modsubdir_%,%,$@) modules
 139
 140 .PHONY: $(patsubst %,_modinst_%,$(MOD_DIRS))
 141 $(patsubst %,_modinst_%,$(MOD_DIRS)) : dummy
 142         $(MAKE) -C $(patsubst _modinst_%,%,$@) modules_install
 143 endif
 144
 145 .PHONY: modules
 146 modules: $(ALL_MOBJS) $(MIX_OBJS) $(MI_OBJS) dummy \
 147          $(patsubst %,_modsubdir_%,$(MOD_DIRS))
 148
 149 .PHONY: _modinst__
 150 _modinst__: dummy
 151 ifneq "$(strip $(ALL_MOBJS))" ""
 152         mkdir -p $(MODLIB)/kernel/$(PDWN)
 153         cp $(ALL_MOBJS) $(MODLIB)/kernel/$(PDWN)
 154 endif
 155
 156 .PHONY: modules_install
 157 modules_install: _modinst__ \
 158          $(patsubst %,_modinst_%,$(MOD_DIRS))
 159
 160 #
 161 # A rule to do nothing
 162 #
 163 dummy:
 164
 165 #
 166 # This is useful for testing
 167 #
 168 script:
 169         $(SCRIPT)
 170
 171 #
 172 # This sets version suffixes on exported symbols
 173 # Uses SYMTAB_OBJS
 174 # Separate the object into "normal" objects and "exporting" objects
 175 # Exporting objects are: all objects that define symbol tables
 176 #
 177 ifdef CONFIG_MODULES
 178
 179 SYMTAB_OBJS = $(LX_OBJS) $(OX_OBJS) $(MX_OBJS) $(MIX_OBJS)
 180
 181 ifdef CONFIG_MODVERSIONS
 182 ifneq "$(strip $(SYMTAB_OBJS))" ""
 183
 184 MODINCL = $(TOPDIR)/include/linux/modules
 185
 186 # The -w option (enable warnings) for genksyms will return here in 2.1
 187 # So where has it gone?
 188 #
 189 # Added the SMP separator to stop module accidents between uniprocessor
 190 # and SMP Intel boxes - AC - from bits by Michael Chastain
 191 #
 192
 193 ifdef CONFIG_SMP
 194         genksyms_smp_prefix := -p smp_
 195 else
 196         genksyms_smp_prefix :=
 197 endif
 198
 199 $(MODINCL)/%.ver: %.c
 200         @if [ ! -r $(MODINCL)/$*.stamp -o $(MODINCL)/$*.stamp -ot $< ]; then \
 201                 echo '$(CC) $(CFLAGS) -E -D__GENKSYMS__ $<'; \
 202                 echo '| $(GENKSYMS) $(genksyms_smp_prefix) -k $(VERSION).$(PATCHLEVEL).$(SUBLEVEL) > $@.tmp'; \
 203                 $(CC) $(CFLAGS) -E -D__GENKSYMS__ $< \
 204                 | $(GENKSYMS) $(genksyms_smp_prefix) -k $(VERSION).$(PATCHLEVEL).$(SUBLEVEL) > $@.tmp; \
 205                 if [ -r $@ ] && cmp -s $@ $@.tmp; then echo $@ is unchanged; rm -f $@.tmp; \
 206                 else echo mv $@.tmp $@; mv -f $@.tmp $@; fi; \
 207         fi; touch $(MODINCL)/$*.stamp
 208
 209 $(addprefix $(MODINCL)/,$(SYMTAB_OBJS:.o=.ver)): $(TOPDIR)/include/linux/autoconf.h
 210
 211 $(TOPDIR)/include/linux/modversions.h: $(addprefix $(MODINCL)/,$(SYMTAB_OBJS:.o=.ver))
 212         @echo updating $(TOPDIR)/include/linux/modversions.h
 213         @(echo "#ifndef _LINUX_MODVERSIONS_H";\
 214           echo "#define _LINUX_MODVERSIONS_H"; \
 215           echo "#include <linux/modsetver.h>"; \
 216           cd $(TOPDIR)/include/linux/modules; \
 217           for f in *.ver; do \
 218             if [ -f $$f ]; then echo "#include <linux/modules/$${f}>"; fi; \
 219           done; \
 220           echo "#endif"; \
 221         ) > $@
 222
 223 dep fastdep: $(TOPDIR)/include/linux/modversions.h
 224
 225 endif # SYMTAB_OBJS
 226
 227 $(M_OBJS): $(TOPDIR)/include/linux/modversions.h
 228 ifdef MAKING_MODULES
 229 $(O_OBJS) $(L_OBJS): $(TOPDIR)/include/linux/modversions.h
 230 endif
 231
 232 else
 233
 234 $(TOPDIR)/include/linux/modversions.h:
 235         @echo "#include <linux/modsetver.h>" > $@
 236
 237 endif # CONFIG_MODVERSIONS
 238
 239 ifneq "$(strip $(SYMTAB_OBJS))" ""
 240 $(SYMTAB_OBJS): $(SYMTAB_OBJS:.o=.c) $(TOPDIR)/include/linux/modversions.h
 241         $(CC) $(CFLAGS) $(EXTRA_CFLAGS) $(CFLAGS_$@) -DEXPORT_SYMTAB -c $(@:.o=.c)
 242         @ ( \
 243             echo 'ifeq ($(strip $(subst $(comma),:,$(CFLAGS) $(EXTRA_CFLAGS) $(CFLAGS_$@) -DEXPORT_SYMTAB)),$$(strip $$(subst $$(comma),:,$$(CFLAGS) $$(EXTRA_CFLAGS) $$(CFLAGS_$@) -DEXPORT_SYMTAB)))' ; \
 244             echo 'FILES_FLAGS_UP_TO_DATE += $@' ; \
 245             echo 'endif' \
 246         ) > $(dir $@)/.$(notdir $@).flags
 247 endif
 248
 249 endif # CONFIG_MODULES
 250
 251
 252 #
 253 # include dependency files if they exist
 254 #
 255 ifneq ($(wildcard .depend),)
 256 include .depend
 257 endif
 258
 259 ifneq ($(wildcard $(TOPDIR)/.hdepend),)
 260 include $(TOPDIR)/.hdepend
 261 endif
 262
 263 #
 264 # Find files whose flags have changed and force recompilation.
 265 # For safety, this works in the converse direction:
 266 #   every file is forced, except those whose flags are positively up-to-date.
 267 #
 268 FILES_FLAGS_UP_TO_DATE :=
 269
 270 # For use in expunging commas from flags, which mung our checking.
 271 comma = ,
 272
 273 FILES_FLAGS_EXIST := $(wildcard .*.flags)
 274 ifneq ($(FILES_FLAGS_EXIST),)
 275 include $(FILES_FLAGS_EXIST)
 276 endif
 277
 278 FILES_FLAGS_CHANGED := $(strip \
 279     $(filter-out $(FILES_FLAGS_UP_TO_DATE), \
 280         $(O_TARGET) $(O_OBJS) $(OX_OBJS) \
 281         $(L_TARGET) $(L_OBJS) $(LX_OBJS) \
 282         $(M_OBJS) $(MX_OBJS) \
 283         $(MI_OBJS) $(MIX_OBJS) \
 284         ))
 285
 286 # A kludge: .S files don't get flag dependencies (yet),
 287 #   because that will involve changing a lot of Makefiles.  Also
 288 #   suppress object files explicitly listed in $(IGNORE_FLAGS_OBJS).
 289 #   This allows handling of assembly files that get translated into
 290 #   multiple object files (see arch/ia64/lib/idiv.S, for example).
 291 FILES_FLAGS_CHANGED := $(strip \
 292     $(filter-out $(patsubst %.S, %.o, $(wildcard *.S) $(IGNORE_FLAGS_OBJS)), \
 293     $(FILES_FLAGS_CHANGED)))
 294
 295 ifneq ($(FILES_FLAGS_CHANGED),)
 296 $(FILES_FLAGS_CHANGED): dummy
 297 endif