LXR linux/tools/build/Build.include

   1###
   2# build: Generic definitions
   3#
   4#  Lots of this code have been borrowed or heavily inspired from parts
   5#  of kbuild code, which is not credited, but mostly developed by:
   6#
   7#  Copyright (C) Sam Ravnborg <sam@mars.ravnborg.org>, 2015
   8#  Copyright (C) Linus Torvalds <torvalds@linux-foundation.org>, 2015
   9#
  10
  11###
  12# Convenient variables
  13comma   := ,
  14squote  := '
  15
  16###
  17# Name of target with a '.' as filename prefix. foo/bar.o => foo/.bar.o
  18dot-target = $(dir $@).$(notdir $@)
  19
  20###
  21# filename of target with directory and extension stripped
  22basetarget = $(basename $(notdir $@))
  23
  24###
  25# The temporary file to save gcc -MD generated dependencies must not
  26# contain a comma
  27depfile = $(subst $(comma),_,$(dot-target).d)
  28
  29###
  30# Check if both arguments has same arguments. Result is empty string if equal.
  31arg-check = $(strip $(filter-out $(cmd_$(1)), $(cmd_$@)) \
  32                    $(filter-out $(cmd_$@),   $(cmd_$(1))) )
  33
  34###
  35# Escape single quote for use in echo statements
  36escsq = $(subst $(squote),'\$(squote)',$1)
  37
  38# Echo command
  39# Short version is used, if $(quiet) equals `quiet_', otherwise full one.
  40echo-cmd = $(if $($(quiet)cmd_$(1)),\
  41           echo '  $(call escsq,$($(quiet)cmd_$(1)))';)
  42
  43###
  44# Replace >$< with >$$< to preserve $ when reloading the .cmd file
  45# (needed for make)
  46# Replace >#< with >\#< to avoid starting a comment in the .cmd file
  47# (needed for make)
  48# Replace >'< with >'\''< to be able to enclose the whole string in '...'
  49# (needed for the shell)
  50make-cmd = $(call escsq,$(subst \#,\\\#,$(subst $$,$$$$,$(cmd_$(1)))))
  51
  52###
  53# Find any prerequisites that is newer than target or that does not exist.
  54# PHONY targets skipped in both cases.
  55any-prereq = $(filter-out $(PHONY),$?) $(filter-out $(PHONY) $(wildcard $^),$^)
  56
  57###
  58# Copy dependency data into .cmd file
  59#  - gcc -M dependency info
  60#  - command line to create object 'cmd_object :='
  61dep-cmd = $(if $(wildcard $(fixdep)),                                           \
  62           $(fixdep) $(depfile) $@ '$(make-cmd)' > $(dot-target).tmp;           \
  63           rm -f $(depfile);                                                    \
  64           mv -f $(dot-target).tmp $(dot-target).cmd,                           \
  65           printf '\# cannot find fixdep (%s)\n' $(fixdep) > $(dot-target).cmd; \
  66           printf '\# using basic dep data\n\n' >> $(dot-target).cmd;           \
  67           cat $(depfile) >> $(dot-target).cmd;                                 \
  68           printf '%s\n' 'cmd_$@ := $(make-cmd)' >> $(dot-target).cmd)
  69
  70###
  71# if_changed_dep  - execute command if any prerequisite is newer than
  72#                   target, or command line has changed and update
  73#                   dependencies in the cmd file
  74if_changed_dep = $(if $(strip $(any-prereq) $(arg-check)),         \
  75        @set -e;                                                   \
  76        $(echo-cmd) $(cmd_$(1)) && $(dep-cmd))
  77
  78# if_changed      - execute command if any prerequisite is newer than
  79#                   target, or command line has changed
  80if_changed = $(if $(strip $(any-prereq) $(arg-check)),             \
  81        @set -e;                                                   \
  82        $(echo-cmd) $(cmd_$(1));                                   \
  83        printf '%s\n' 'cmd_$@ := $(make-cmd)' > $(dot-target).cmd)
  84
  85###
  86# C flags to be used in rule definitions, includes:
  87# - depfile generation
  88# - global $(CFLAGS)
  89# - per target C flags
  90# - per object C flags
  91# - BUILD_STR macro to allow '-D"$(variable)"' constructs
  92c_flags = -Wp,-MD,$(depfile),-MT,$@ $(CFLAGS) -D"BUILD_STR(s)=\#s" $(CFLAGS_$(basetarget).o) $(CFLAGS_$(obj))
  93cxx_flags = -Wp,-MD,$(depfile),-MT,$@ $(CXXFLAGS) -D"BUILD_STR(s)=\#s" $(CXXFLAGS_$(basetarget).o) $(CXXFLAGS_$(obj))
  94
  95###
  96## HOSTCC C flags
  97
  98host_c_flags = -Wp,-MD,$(depfile),-MT,$@ $(CHOSTFLAGS) -D"BUILD_STR(s)=\#s" $(CHOSTFLAGS_$(basetarget).o) $(CHOSTFLAGS_$(obj))
  99