path: root/Rules.mak

# Rules.make for busybox
#
# Copyright (C) 1999-2005 by Erik Andersen <andersen@codepoet.org>
#
# Licensed under GPLv2, see the file LICENSE in this tarball for details.
#

# Pull in the user's busybox configuration
ifeq ($(filter $(noconfig_targets),$(MAKECMDGOALS)),)
-include $(top_builddir)/.config
endif

#--------------------------------------------------------
PROG      := busybox
MAJOR_VERSION   :=1
MINOR_VERSION   :=1
SUBLEVEL_VERSION:=1
EXTRAVERSION    :=-pre0
VERSION   :=$(MAJOR_VERSION).$(MINOR_VERSION).$(SUBLEVEL_VERSION)$(EXTRAVERSION)
BUILDTIME := $(shell TZ=UTC date -u "+%Y.%m.%d-%H:%M%z")


#--------------------------------------------------------
# With a modern GNU make(1) (highly recommended, that's what all the
# developers use), all of the following configuration values can be
# overridden at the command line.  For example:
#   make CROSS=powerpc-linux- top_srcdir="$HOME/busybox" PREFIX=/mnt/app
#--------------------------------------------------------

# If you are running a cross compiler, you will want to set 'CROSS'
# to something more interesting...  Target architecture is determined
# by asking the CC compiler what arch it compiles things for, so unless
# your compiler is broken, you should not need to specify TARGET_ARCH
CROSS           =$(subst ",, $(strip $(CROSS_COMPILER_PREFIX)))
CC             = $(CROSS)gcc
AR             = $(CROSS)ar
AS             = $(CROSS)as
LD             = $(CROSS)ld
NM             = $(CROSS)nm
STRIP          = $(CROSS)strip
CPP            = $(CC) -E
# MAKEFILES      = $(top_builddir)/.config
RM             = rm
RM_F           = $(RM) -f
LN             = ln
LN_S           = $(LN) -s
MKDIR          = mkdir
MKDIR_P        = $(MKDIR) -p
MV             = mv
CP             = cp


# What OS are you compiling busybox for?  This allows you to include
# OS specific things, syscall overrides, etc.
TARGET_OS=linux

# Select the compiler needed to build binaries for your development system
HOSTCC    = gcc
HOSTCFLAGS= -Wall -Wstrict-prototypes -O2 -fomit-frame-pointer

# Ensure consistent sort order, 'gcc -print-search-dirs' behavior, etc.
LC_ALL:= C

# If you want to add some simple compiler switches (like -march=i686),
# especially from the command line, use this instead of CFLAGS directly.
# For optimization overrides, it's better still to set OPTIMIZATION.
CFLAGS_EXTRA=$(subst ",, $(strip $(EXTRA_CFLAGS_OPTIONS)))

# To compile vs some other alternative libc, you may need to use/adjust
# the following lines to meet your needs...
#
# If you are using Red Hat 6.x with the compatible RPMs (for developing under
# Red Hat 5.x and glibc 2.0) uncomment the following.  Be sure to read about
# using the compatible RPMs (compat-*) at http://www.redhat.com !
#LIBCDIR:=/usr/i386-glibc20-linux
#
# For other libraries, you are on your own.  But these may (or may not) help...
#LDFLAGS+=-nostdlib
#LIBRARIES:=$(LIBCDIR)/lib/libc.a -lgcc
#CROSS_CFLAGS+=-nostdinc -I$(LIBCDIR)/include -I$(GCCINCDIR) -funsigned-char
#GCCINCDIR:=$(shell gcc -print-search-dirs | sed -ne "s/install: \(.*\)/\1include/gp")

WARNINGS=-Wall -Wstrict-prototypes -Wshadow
CFLAGS+=-I$(top_builddir)/include -I$(top_srcdir)/include -I$(srcdir)

ARFLAGS=cru


# gcc centric. Perhaps fiddle with findstring gcc,$(CC) for the rest
# get the CC MAJOR/MINOR version
CC_MAJOR:=$(shell printf "%02d" $(shell echo __GNUC__ | $(CC) -E -xc - | tail -n 1))
CC_MINOR:=$(shell printf "%02d" $(shell echo __GNUC_MINOR__ | $(CC) -E -xc - | tail -n 1))

#--------------------------------------------------------
export VERSION BUILDTIME HOSTCC HOSTCFLAGS CROSS CC AR AS LD NM STRIP CPP
ifeq ($(strip $(TARGET_ARCH)),)
TARGET_ARCH:=$(shell $(CC) -dumpmachine | sed -e s'/-.*//' \
		-e 's/i.86/i386/' \
		-e 's/sparc.*/sparc/' \
		-e 's/arm.*/arm/g' \
		-e 's/m68k.*/m68k/' \
		-e 's/ppc/powerpc/g' \
		-e 's/v850.*/v850/g' \
		-e 's/sh[234]/sh/' \
		-e 's/mips-.*/mips/' \
		-e 's/mipsel-.*/mipsel/' \
		-e 's/cris.*/cris/' \
		)
endif

# A nifty macro to make testing gcc features easier
check_gcc=$(shell \
	if [ "$(1)" != "" ]; then \
		if $(CC) $(1) -S -o /dev/null -xc /dev/null > /dev/null 2>&1; \
		then echo "$(1)"; else echo "$(2)"; fi \
	fi)

# A not very robust macro to check for available ld flags
check_ld=$(shell \
	echo "checking='$(1)'" >> foo.txt ; \
	if [ "x$(1)" != "x" ]; then \
		$(LD) --help | grep -q \\$(1) && echo "-Wl,$(1)$(2)" ; \
	fi)

# A not very robust macro to check for available as flags
check_as=$(shell \
	if [ "x$(1)" != "x" ]; then \
		$(AS) --help | grep -q "\\$(1)" && echo "-Wa,$(1)$(2)" ; \
	fi)


# Setup some shortcuts so that silent mode is silent like it should be
ifeq ($(subst s,,$(MAKEFLAGS)),$(MAKEFLAGS))
export MAKE_IS_SILENT=n
SECHO=@echo
else
export MAKE_IS_SILENT=y
SECHO=-@false
endif

#CFLAGS+=$(call check_gcc,-funsigned-char,)

CFLAGS+=$(call check_gcc,-mmax-stack-frame=256,)

#--------------------------------------------------------
# Arch specific compiler optimization stuff should go here.
# Unless you want to override the defaults, do not set anything
# for OPTIMIZATION...

# use '-Os' optimization if available, else use -O2
OPTIMIZATION:=$(call check_gcc,-Os,-O2)

ifeq ($(CONFIG_BUILD_AT_ONCE),y)
# gcc 2.95 exits with 0 for "unrecognized option"
ifeq ($(strip $(shell [ $(CC_MAJOR) -ge 3 ] ; echo $$?)),0)
	OPTIMIZATION+=$(call check_gcc,--combine,)
endif
OPTIMIZATION+=$(call check_gcc,-funit-at-a-time,)
PROG_CFLAGS+=$(call check_gcc,-fwhole-program,)
endif # CONFIG_BUILD_AT_ONCE

LIB_LDFLAGS:=$(call check_ld,--enable-new-dtags,)
#LIB_LDFLAGS+=$(call check_ld,--reduce-memory-overheads,)
#LIB_LDFLAGS+=$(call check_ld,--as-needed,)
#LIB_LDFLAGS+=$(call check_ld,--warn-shared-textrel,)


# Some nice architecture specific optimizations
ifeq ($(strip $(TARGET_ARCH)),arm)
	OPTIMIZATION+=-fstrict-aliasing
endif
ifeq ($(strip $(TARGET_ARCH)),i386)
	OPTIMIZATION+=$(call check_gcc,-march=i386,)
# gcc-4.0 and older seem to suffer from these
ifneq ($(strip $(shell [ $(CC_MAJOR) -ge 4 -a $(CC_MINOR) -ge 1 ] ; echo $$?)),0)
	OPTIMIZATION+=$(call check_gcc,-mpreferred-stack-boundary=2,)
	OPTIMIZATION+=$(call check_gcc,-falign-functions=0 -falign-jumps=0 -falign-loops=0,\
		-malign-functions=0 -malign-jumps=0 -malign-loops=0)
endif # gcc-4.0 and older

# gcc-4.1 and beyond seem to benefit from these
ifeq ($(strip $(shell [ $(CC_MAJOR) -ge 4 -a $(CC_MINOR) -ge 1 ] ; echo $$?)),0)
	# turn off flags which hurt -Os
	OPTIMIZATION+=$(call check_gcc,-fno-tree-loop-optimize,)
	OPTIMIZATION+=$(call check_gcc,-fno-tree-dominator-opts,)
	OPTIMIZATION+=$(call check_gcc,-fno-strength-reduce,)

	OPTIMIZATION+=$(call check_gcc,-fno-branch-count-reg,)
endif # gcc-4.1 and beyond
endif
OPTIMIZATIONS:=$(OPTIMIZATION) $(call check_gcc,-fomit-frame-pointer,)

#
#--------------------------------------------------------
# If you're going to do a lot of builds with a non-vanilla configuration,
# it makes sense to adjust parameters above, so you can type "make"
# by itself, instead of following it by the same half-dozen overrides
# every time.  The stuff below, on the other hand, is probably less
# prone to casual user adjustment.
#

ifeq ($(strip $(CONFIG_LFS)),y)
    # For large file summit support
    CFLAGS+=-D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64
endif
ifeq ($(strip $(CONFIG_DMALLOC)),y)
    # For testing mem leaks with dmalloc
    CFLAGS+=-DDMALLOC
    LIBRARIES:=-ldmalloc
else
    ifeq ($(strip $(CONFIG_EFENCE)),y)
	LIBRARIES:=-lefence
    endif
endif
ifeq ($(strip $(CONFIG_DEBUG)),y)
    CFLAGS  +=$(WARNINGS) -g -D_GNU_SOURCE
    LDFLAGS += $(call check_ld,-warn-common,)
    STRIPCMD:=/bin/true -Not_stripping_since_we_are_debugging
else
    CFLAGS+=$(WARNINGS) $(OPTIMIZATIONS) -D_GNU_SOURCE -DNDEBUG
    LDFLAGS += $(call check_ld,-warn-common,)
    LDFLAGS += $(call check_ld,--sort-common,)
    STRIPCMD:=$(STRIP) -s --remove-section=.note --remove-section=.comment
endif
ifeq ($(strip $(CONFIG_STATIC)),y)
    LDFLAGS += $(call check_ld,--static,)
#else
#    LIBRARIES += -ldl
endif

ifeq ($(strip $(CONFIG_BUILD_LIBBUSYBOX)),y)
    CFLAGS_PIC:= $(call check_gcc,-fPIC,)
endif

ifeq ($(strip $(CONFIG_SELINUX)),y)
    LIBRARIES += -lselinux
endif

ifeq ($(strip $(PREFIX)),)
    PREFIX:=`pwd`/_install
endif

# Additional complications due to support for pristine source dir.
# Include files in the build directory should take precedence over
# the copy in top_srcdir, both during the compilation phase and the
# shell script that finds the list of object files.
# Work in progress by <ldoolitt@recycle.lbl.gov>.


OBJECTS:=$(APPLET_SOURCES:.c=.o) busybox.o usage.o applets.o
CFLAGS    += $(CROSS_CFLAGS)
ifdef BB_INIT_SCRIPT
    CFLAGS += -DINIT_SCRIPT='"$(BB_INIT_SCRIPT)"'
endif

# Put user-supplied flags at the end, where they
# have a chance of winning.
CFLAGS += $(CFLAGS_EXTRA)

#------------------------------------------------------------
# Installation options
ifeq ($(strip $(CONFIG_INSTALL_APPLET_HARDLINKS)),y)
INSTALL_OPTS=--hardlinks
endif
ifeq ($(strip $(CONFIG_INSTALL_APPLET_SYMLINKS)),y)
INSTALL_OPTS=--symlinks
endif
ifeq ($(strip $(CONFIG_INSTALL_APPLET_DONT)),y)
INSTALL_OPTS=
endif

.PHONY: dummy