rust/Makefile.in

# Copyright 2012 The Rust Project Developers. See the COPYRIGHT
# file at the top-level directory of this distribution and at
# http://rust-lang.org/COPYRIGHT.
#
# Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
# http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
# <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
# option. This file may not be copied, modified, or distributed
# except according to those terms.

# An explanation of how the build is structured:
#
# There are multiple build stages (0-3) needed to verify that the
# compiler is properly self-hosting. Each stage is divided between
# 'host' artifacts and 'target' artifacts, where the stageN host
# compiler builds artifacts for 1 or more stageN target architectures.
# Once the stageN target compiler has been built for the host
# architecture it is promoted (copied) to a stageN+1 host artifact.
#
# The stage3 host compiler is a compiler that successfully builds
# itself and should (in theory) be bitwise identical to the stage2
# host compiler. The process is bootstrapped using a stage0 host
# compiler downloaded from a previous snapshot.
#
# At no time should stageN artifacts be interacting with artifacts
# from other stages. For consistency, we use the 'promotion' logic
# for all artifacts, even those that don't make sense on non-host
# architectures.
#
# The directory layout for a stage is intended to match the layout
# of the installed compiler, and looks like the following:
#
# stageN - this is the system root, corresponding to, e.g. /usr
#   bin - binaries compiled for the host
#   lib - libraries used by the host compiler
#     rustlib - rustc's own place to organize libraries
#       $(target) - target-specific artifacts
#         bin - binaries for target architectures
#         lib - libraries for target architectures
#
# A note about host libraries:
#
# The only libraries that get promoted to stageN/lib are those needed
# by rustc. In general, rust programs, even those compiled for the
# host architecture will use libraries from the target
# directories. This gives rust some freedom to experiment with how
# libraries are managed and versioned without polluting the common
# areas of the filesystem.
#
# General rust binaries may stil live in the host bin directory; they
# will just link against the libraries in the target lib directory.
#
# Admittedly this is a little convoluted.

STAGES = 0 1 2 3

######################################################################
# Residual auto-configuration
######################################################################

# Recursive wildcard function
# http://blog.jgc.org/2011/07/gnu-make-recursive-wildcard-function.html
rwildcard=$(foreach d,$(wildcard $1*),$(call rwildcard,$d/,$2) \
  $(filter $(subst *,%,$2),$d))

include config.mk

# We track all of the object files we might build so that we can find
# and include all of the .d files in one fell swoop.
ALL_OBJ_FILES :=

MKFILE_DEPS := config.stamp $(call rwildcard,$(CFG_SRC_DIR)mk/,*)
NON_BUILD_HOST = $(filter-out $(CFG_BUILD),$(CFG_HOST))
NON_BUILD_TARGET = $(filter-out $(CFG_BUILD),$(CFG_TARGET))

ifneq ($(MAKE_RESTARTS),)
CFG_INFO := $(info cfg: make restarts: $(MAKE_RESTARTS))
endif

CFG_INFO := $(info cfg: build triple $(CFG_BUILD))
CFG_INFO := $(info cfg: host triples $(CFG_HOST))
CFG_INFO := $(info cfg: target triples $(CFG_TARGET))

ifneq ($(wildcard $(NON_BUILD_HOST)),)
CFG_INFO := $(info cfg: non-build host triples $(NON_BUILD_HOST))
endif
ifneq ($(wildcard $(NON_BUILD_TARGET)),)
CFG_INFO := $(info cfg: non-build target triples $(NON_BUILD_TARGET))
endif

CFG_RUSTC_FLAGS := $(RUSTFLAGS)
CFG_GCCISH_CFLAGS :=
CFG_GCCISH_LINK_FLAGS :=

ifdef CFG_DISABLE_OPTIMIZE
  $(info cfg: disabling rustc optimization (CFG_DISABLE_OPTIMIZE))
  CFG_RUSTC_FLAGS +=
else
  # The rtopt cfg turns off runtime sanity checks
  CFG_RUSTC_FLAGS += -O --cfg rtopt
endif

ifdef CFG_DISABLE_DEBUG
  CFG_RUSTC_FLAGS += --cfg ndebug
  CFG_GCCISH_CFLAGS += -DRUST_NDEBUG
else
  $(info cfg: enabling more debugging (CFG_ENABLE_DEBUG))
  CFG_RUSTC_FLAGS += --cfg debug
  CFG_GCCISH_CFLAGS += -DRUST_DEBUG
endif

ifdef SAVE_TEMPS
  CFG_RUSTC_FLAGS += --save-temps
endif
ifdef ASM_COMMENTS
  CFG_RUSTC_FLAGS += -Z asm-comments
endif
ifdef TIME_PASSES
  CFG_RUSTC_FLAGS += -Z time-passes
endif
ifdef TIME_LLVM_PASSES
  CFG_RUSTC_FLAGS += -Z time-llvm-passes
endif
ifdef TRACE
  CFG_RUSTC_FLAGS += -Z trace
endif
ifdef CFG_DISABLE_RPATH
CFG_RUSTC_FLAGS += -C no-rpath
endif

# The executables crated during this compilation process have no need to include
# static copies of libstd and libextra. We also generate dynamic versions of all
# libraries, so in the interest of space, prefer dynamic linking throughout the
# compilation process.
#
# Note though that these flags are omitted for stage2+. This means that the
# snapshot will be generated with a statically linked rustc so we only have to
# worry about the distribution of one file (with its native dynamic
# dependencies)
RUSTFLAGS_STAGE0 += -C prefer-dynamic
RUSTFLAGS_STAGE1 += -C prefer-dynamic

# platform-specific auto-configuration
include $(CFG_SRC_DIR)mk/platform.mk

# Run the stage1/2 compilers under valgrind
ifdef VALGRIND_COMPILE
  CFG_VALGRIND_COMPILE :=$(CFG_VALGRIND)
else
  CFG_VALGRIND_COMPILE :=
endif

# version-string calculation
CFG_GIT_DIR := $(CFG_SRC_DIR).git
CFG_RELEASE = 0.10-pre
CFG_VERSION = $(CFG_RELEASE)
# windows exe's need numeric versions - don't use anything but
# numbers and dots here
CFG_VERSION_WIN = 0.10

# since $(CFG_GIT) may contain spaces (especially on Windows),
# we need to escape them. (" " to r"\ ")
# Note that $(subst ...) ignores space after `subst`,
# so we use a hack: define $(SPACE) which contains space character.
SPACE :=
SPACE +=
ifneq ($(wildcard $(subst $(SPACE),\$(SPACE),$(CFG_GIT))),)
ifneq ($(wildcard $(subst $(SPACE),\$(SPACE),$(CFG_GIT_DIR))),)
    CFG_VERSION += $(shell git --git-dir='$(CFG_GIT_DIR)' log -1 \
                     --pretty=format:'(%h %ci)')
    CFG_VER_HASH = $(shell git --git-dir='$(CFG_GIT_DIR)' rev-parse HEAD)
endif
endif

ifdef CFG_ENABLE_VALGRIND
  $(info cfg: enabling valgrind (CFG_ENABLE_VALGRIND))
else
  CFG_VALGRIND :=
endif
ifdef CFG_BAD_VALGRIND
  $(info cfg: disabling valgrind due to its unreliability on this platform)
  CFG_VALGRIND :=
endif


######################################################################
# Target-and-rule "utility variables"
######################################################################

ifdef VERBOSE
  Q :=
  E =
else
  Q := @
  E = echo $(1)
endif

S := $(CFG_SRC_DIR)

define DEF_X
X_$(1) := $(CFG_EXE_SUFFIX_$(1))
endef
$(foreach target,$(CFG_TARGET),\
  $(eval $(call DEF_X,$(target))))

# "Source" files we generate in builddir along the way.
GENERATED :=

# Delete the built-in rules.
.SUFFIXES:
%:: %,v
%:: RCS/%,v
%:: RCS/%
%:: s.%
%:: SCCS/s.%


######################################################################
# Cleaning out old crates
######################################################################

# $(1) is the path for directory to match against
# $(2) is the glob to use in the match
#
# Note that a common bug is to accidentally construct the glob denoted
# by $(2) with a space character prefix, which invalidates the
# construction $(1)$(2).
define CHECK_FOR_OLD_GLOB_MATCHES
  $(Q)MATCHES="$(wildcard $(1))"; if [ -n "$$MATCHES" ] ; then echo "warning: there are previous" \'$(notdir $(2))\' "libraries:" $$MATCHES; fi
endef

# Same interface as above, but deletes rather than just listing the files.
ifdef VERBOSE
define REMOVE_ALL_OLD_GLOB_MATCHES
  $(Q)MATCHES="$(wildcard $(1))"; if [ -n "$$MATCHES" ] ; then echo "warning: removing previous" \'$(notdir $(1))\' "libraries:" $$MATCHES; rm $$MATCHES ; fi
endef
else
define REMOVE_ALL_OLD_GLOB_MATCHES
  $(Q)MATCHES="$(wildcard $(1))"; if [ -n "$$MATCHES" ] ; then rm $$MATCHES ; fi
endef
endif

# We use a different strategy for LIST_ALL_OLD_GLOB_MATCHES_EXCEPT
# than in the macros above because it needs the result of running the
# `ls` command after other rules in the command list have run; the
# macro-expander for $(wildcard ...) would deliver its results too
# soon. (This is in contrast to the macros above, which are meant to
# be run at the outset of a command list in a rule.)
ifdef VERBOSE
define LIST_ALL_OLD_GLOB_MATCHES
  @echo "info: now are following matches for" '$(notdir $(1))' "libraries:"
  @( ls $(1) 2>/dev/null || true )
endef
else
define LIST_ALL_OLD_GLOB_MATCHES
endef
endif

######################################################################
# LLVM macros
######################################################################

# FIXME: x86-ism
LLVM_COMPONENTS=x86 arm mips ipo bitreader bitwriter linker asmparser jit mcjit \
                interpreter instrumentation

# Only build these LLVM tools
LLVM_TOOLS=bugpoint llc llvm-ar llvm-as llvm-dis llvm-mc opt llvm-extract

define DEF_LLVM_VARS
# The configure script defines these variables with the target triples
# separated by Z. This defines new ones with the expected format.
CFG_LLVM_BUILD_DIR_$(1):=$$(CFG_LLVM_BUILD_DIR_$(subst -,_,$(1)))
CFG_LLVM_INST_DIR_$(1):=$$(CFG_LLVM_INST_DIR_$(subst -,_,$(1)))

# Any rules that depend on LLVM should depend on LLVM_CONFIG
LLVM_CONFIG_$(1):=$$(CFG_LLVM_INST_DIR_$(1))/bin/llvm-config$$(X_$(1))
LLVM_MC_$(1):=$$(CFG_LLVM_INST_DIR_$(1))/bin/llvm-mc$$(X_$(1))
LLVM_VERSION_$(1)=$$(shell "$$(LLVM_CONFIG_$(1))" --version)
LLVM_BINDIR_$(1)=$$(shell "$$(LLVM_CONFIG_$(1))" --bindir)
LLVM_INCDIR_$(1)=$$(shell "$$(LLVM_CONFIG_$(1))" --includedir)
LLVM_LIBDIR_$(1)=$$(shell "$$(LLVM_CONFIG_$(1))" --libdir)
LLVM_LIBS_$(1)=$$(shell "$$(LLVM_CONFIG_$(1))" --libs $$(LLVM_COMPONENTS))
LLVM_LDFLAGS_$(1)=$$(shell "$$(LLVM_CONFIG_$(1))" --ldflags)
# On FreeBSD, it may search wrong headers (that are for pre-installed LLVM),
# so we replace -I with -iquote to ensure that it searches bundled LLVM first.
LLVM_CXXFLAGS_$(1)=$$(subst -I, -iquote , $$(shell "$$(LLVM_CONFIG_$(1))" --cxxflags))
LLVM_HOST_TRIPLE_$(1)=$$(shell "$$(LLVM_CONFIG_$(1))" --host-target)

LLVM_AS_$(1)=$$(CFG_LLVM_INST_DIR_$(1))/bin/llvm-as$$(X_$(1))
LLC_$(1)=$$(CFG_LLVM_INST_DIR_$(1))/bin/llc$$(X_$(1))

endef

$(foreach host,$(CFG_HOST), \
 $(eval $(call DEF_LLVM_VARS,$(host))))

######################################################################
# Exports for sub-utilities
######################################################################

# Note that any variable that re-configure should pick up needs to be
# exported

export CFG_SRC_DIR
export CFG_BUILD_DIR
export CFG_VERSION
export CFG_VERSION_WIN
export CFG_RELEASE
export CFG_BUILD
export CFG_LLVM_ROOT
export CFG_ENABLE_MINGW_CROSS
export CFG_PREFIX
export CFG_LIBDIR
export CFG_RUSTLIBDIR
export CFG_LIBDIR_RELATIVE
export CFG_DISABLE_INJECT_STD_VERSION

######################################################################
# Per-stage targets and runner
######################################################################

include $(CFG_SRC_DIR)mk/crates.mk

define SREQ
# $(1) is the stage number
# $(2) is the target triple
# $(3) is the host triple

# Destinations of artifacts for the host compiler
HROOT$(1)_H_$(3) = $(3)/stage$(1)
HBIN$(1)_H_$(3) = $$(HROOT$(1)_H_$(3))/bin
HLIB$(1)_H_$(3) = $$(HROOT$(1)_H_$(3))/$$(CFG_LIBDIR_RELATIVE)

# Destinations of artifacts for target architectures
TROOT$(1)_T_$(2)_H_$(3) = $$(HLIB$(1)_H_$(3))/$$(CFG_RUSTLIBDIR)/$(2)
TBIN$(1)_T_$(2)_H_$(3) = $$(TROOT$(1)_T_$(2)_H_$(3))/bin
TLIB$(1)_T_$(2)_H_$(3) = $$(TROOT$(1)_T_$(2)_H_$(3))/lib

# Preqrequisites for using the stageN compiler
ifeq ($(1),0)
HSREQ$(1)_H_$(3) = $$(HBIN$(1)_H_$(3))/rustc$$(X_$(3))
else
HSREQ$(1)_H_$(3) = \
	$$(HBIN$(1)_H_$(3))/rustc$$(X_$(3)) \
	$$(HLIB$(1)_H_$(3))/stamp.rustc \
	$$(foreach dep,$$(RUST_DEPS_rustc),$$(HLIB$(1)_H_$(3))/stamp.$$(dep)) \
	$$(MKFILE_DEPS)
endif

# Prerequisites for using the stageN compiler to build target artifacts
TSREQ$(1)_T_$(2)_H_$(3) = \
	$$(HSREQ$(1)_H_$(3)) \
	$$(TLIB$(1)_T_$(2)_H_$(3))/libmorestack.a \
	$$(TLIB$(1)_T_$(2)_H_$(3))/libcompiler-rt.a

# Prerequisites for a working stageN compiler and libraries, for a specific
# target
SREQ$(1)_T_$(2)_H_$(3) = \
	$$(TSREQ$(1)_T_$(2)_H_$(3)) \
	$$(foreach dep,$$(TARGET_CRATES),\
	    $$(TLIB$(1)_T_$(2)_H_$(3))/stamp.$$(dep))

# Prerequisites for a working stageN compiler and complete set of target
# libraries
CSREQ$(1)_T_$(2)_H_$(3) = \
	$$(TSREQ$(1)_T_$(2)_H_$(3)) \
	$$(HBIN$(1)_H_$(3))/rustdoc$$(X_$(3)) \
	$$(foreach dep,$$(CRATES),$$(TLIB$(1)_T_$(2)_H_$(3))/stamp.$$(dep)) \
	$$(foreach dep,$$(HOST_CRATES),$$(HLIB$(1)_H_$(3))/stamp.$$(dep))

ifeq ($(1),0)
# Don't run the the stage0 compiler under valgrind - that ship has sailed
CFG_VALGRIND_COMPILE$(1) =
else
CFG_VALGRIND_COMPILE$(1) = $$(CFG_VALGRIND_COMPILE)
endif

# Add RUSTFLAGS_STAGEN values to the build command
EXTRAFLAGS_STAGE$(1) = $$(RUSTFLAGS_STAGE$(1))

CFGFLAG$(1)_T_$(2)_H_$(3) = stage$(1)

# Pass --cfg stage0 only for the build->host part of stage0;
# if you're building a cross config, the host->* parts are
# effectively stage1, since it uses the just-built stage0.
ifeq ($(1),0)
ifneq ($(strip $(CFG_BUILD)),$(strip $(3)))
CFGFLAG$(1)_T_$(2)_H_$(3) = stage1
endif
endif

ifdef CFG_DISABLE_RPATH
ifeq ($$(OSTYPE_$(3)),apple-darwin)
  RPATH_VAR$(1)_T_$(2)_H_$(3) := \
      DYLD_LIBRARY_PATH="$$$$DYLD_LIBRARY_PATH:$$(HLIB$(1)_H_$(3))"
else
  RPATH_VAR$(1)_T_$(2)_H_$(3) := \
      LD_LIBRARY_PATH="$$$$LD_LIBRARY_PATH:$$(HLIB$(1)_H_$(3))"
endif
else
    RPATH_VAR$(1)_T_$(2)_H_$(3) :=
endif

STAGE$(1)_T_$(2)_H_$(3) := 						\
	$$(Q)$$(RPATH_VAR$(1)_T_$(2)_H_$(3))                            \
		$$(call CFG_RUN_TARG_$(3),$(1),				\
		$$(CFG_VALGRIND_COMPILE$(1))				\
		$$(HBIN$(1)_H_$(3))/rustc$$(X_$(3))			\
		--cfg $$(CFGFLAG$(1)_T_$(2)_H_$(3))			\
		$$(CFG_RUSTC_FLAGS) $$(EXTRAFLAGS_STAGE$(1)) --target=$(2)) \
                $$(RUSTC_FLAGS_$(2))

PERF_STAGE$(1)_T_$(2)_H_$(3) :=						\
	$$(Q)$$(call CFG_RUN_TARG_$(3),$(1),				\
		$$(CFG_PERF_TOOL) 					\
		$$(HBIN$(1)_H_$(3))/rustc$$(X_$(3))			\
		--cfg $$(CFGFLAG$(1)_T_$(2)_H_$(3))			\
		$$(CFG_RUSTC_FLAGS) $$(EXTRAFLAGS_STAGE$(1)) --target=$(2)) \
                $$(RUSTC_FLAGS_$(2))

endef

$(foreach build,$(CFG_HOST), \
 $(eval $(foreach target,$(CFG_TARGET), \
  $(eval $(foreach stage,$(STAGES), \
   $(eval $(call SREQ,$(stage),$(target),$(build))))))))

######################################################################
# rustc-H-targets
#
# Builds a functional Rustc for the given host.
######################################################################

define DEF_RUSTC_STAGE_TARGET
# $(1) == architecture
# $(2) == stage

rustc-stage$(2)-H-$(1):							\
	$$(foreach target,$$(CFG_TARGET),$$(SREQ$(2)_T_$$(target)_H_$(1)))

endef

$(foreach host,$(CFG_HOST),						\
 $(eval $(foreach stage,1 2 3,						\
  $(eval $(call DEF_RUSTC_STAGE_TARGET,$(host),$(stage))))))

rustc-stage1: rustc-stage1-H-$(CFG_BUILD)
rustc-stage2: rustc-stage2-H-$(CFG_BUILD)
rustc-stage3: rustc-stage3-H-$(CFG_BUILD)

define DEF_RUSTC_TARGET
# $(1) == architecture

rustc-H-$(1): rustc-stage2-H-$(1)
endef

$(foreach host,$(CFG_TARGET),			\
 $(eval $(call DEF_RUSTC_TARGET,$(host))))

rustc-stage1: rustc-stage1-H-$(CFG_BUILD)
rustc-stage2: rustc-stage2-H-$(CFG_BUILD)
rustc-stage3: rustc-stage3-H-$(CFG_BUILD)
rustc: rustc-H-$(CFG_BUILD)

rustc-H-all: $(foreach host,$(CFG_HOST),rustc-H-$(host))

######################################################################
# Entrypoint rule
######################################################################

.DEFAULT_GOAL := all

ifneq ($(CFG_IN_TRANSITION),)

CFG_INFO := $(info cfg:)
CFG_INFO := $(info cfg: *** compiler is in snapshot transition ***)
CFG_INFO := $(info cfg: *** stage2 and later will not be built ***)
CFG_INFO := $(info cfg:)

#FIXME This is surely busted
all: $(SREQ1$(CFG_BUILD)) $(GENERATED) docs

else

define ALL_TARGET_N
ifneq ($$(findstring $(1),$$(CFG_HOST)),)
# This is a host
all-target-$(1)-host-$(2): $$(CSREQ2_T_$(1)_H_$(2))
else
# This is a target only
all-target-$(1)-host-$(2): $$(SREQ2_T_$(1)_H_$(2))
endif
endef

$(foreach target,$(CFG_TARGET), \
 $(foreach host,$(CFG_HOST), \
 $(eval $(call ALL_TARGET_N,$(target),$(host)))))

ALL_TARGET_RULES = $(foreach target,$(CFG_TARGET), \
	$(foreach host,$(CFG_HOST), \
 all-target-$(target)-host-$(host)))

all: $(ALL_TARGET_RULES) $(GENERATED) docs

endif


######################################################################
# Re-configuration
######################################################################

ifndef CFG_DISABLE_MANAGE_SUBMODULES
# This is a pretty expensive operation but I don't see any way to avoid it
NEED_GIT_RECONFIG=$(shell cd "$(CFG_SRC_DIR)" && "$(CFG_GIT)" submodule status | grep -c '^\(+\|-\)')
else
NEED_GIT_RECONFIG=0
endif

ifeq ($(NEED_GIT_RECONFIG),0)
else
# If the submodules have changed then always execute config.mk
.PHONY: config.stamp
endif

Makefile config.mk: config.stamp

config.stamp: $(S)configure $(S)Makefile.in $(S)src/snapshots.txt
	@$(call E, cfg: reconfiguring)
	$(Q)$(S)configure $(CFG_CONFIGURE_ARGS)


######################################################################
# Primary-target makefiles
######################################################################

# Issue #9531: If you change the order of any of the following (or add
# new definitions), make sure definitions always precede their uses,
# especially for the dependency lists of recipes.

include $(CFG_SRC_DIR)mk/rt.mk
include $(CFG_SRC_DIR)mk/target.mk
include $(CFG_SRC_DIR)mk/host.mk
include $(CFG_SRC_DIR)mk/stage0.mk
include $(CFG_SRC_DIR)mk/rustllvm.mk
include $(CFG_SRC_DIR)mk/docs.mk
include $(CFG_SRC_DIR)mk/llvm.mk

######################################################################
# Secondary makefiles, conditionalized for speed
######################################################################

ifneq ($(strip $(findstring dist,$(MAKECMDGOALS))   \
               $(findstring check,$(MAKECMDGOALS))  \
               $(findstring test,$(MAKECMDGOALS))   \
               $(findstring tidy,$(MAKECMDGOALS))   \
               $(findstring clean,$(MAKECMDGOALS))),)
  CFG_INFO := $(info cfg: including dist rules)
  include $(CFG_SRC_DIR)mk/dist.mk
endif

ifneq ($(strip $(findstring snap,$(MAKECMDGOALS))   \
               $(findstring clean,$(MAKECMDGOALS))),)
  CFG_INFO := $(info cfg: including snap rules)
  include $(CFG_SRC_DIR)mk/snap.mk
endif

ifneq ($(strip $(findstring check,$(MAKECMDGOALS)) \
               $(findstring test,$(MAKECMDGOALS))  \
               $(findstring perf,$(MAKECMDGOALS))  \
               $(findstring tidy,$(MAKECMDGOALS))),)
  CFG_INFO := $(info cfg: including test rules)
  include $(CFG_SRC_DIR)mk/tests.mk
endif

ifneq ($(findstring perf,$(MAKECMDGOALS)),)
  CFG_INFO := $(info cfg: including perf rules)
  include $(CFG_SRC_DIR)mk/perf.mk
endif

ifneq ($(findstring clean,$(MAKECMDGOALS)),)
  CFG_INFO := $(info cfg: including clean rules)
  include $(CFG_SRC_DIR)mk/clean.mk
endif

ifneq ($(findstring install,$(MAKECMDGOALS)),)
  CFG_INFO := $(info cfg: including install rules)
  include $(CFG_SRC_DIR)mk/install.mk
endif

ifneq ($(strip $(findstring TAGS.emacs,$(MAKECMDGOALS)) \
               $(findstring TAGS.vi,$(MAKECMDGOALS))),)
  CFG_INFO := $(info cfg: including ctags rules)
  include $(CFG_SRC_DIR)mk/ctags.mk
endif

# Find all of the .d files and include them to add information about
# header file dependencies.
ALL_DEP_FILES := $(ALL_OBJ_FILES:%.o=%.d)
-include $(ALL_DEP_FILES)