tc_version_is_at_least 4.4 && IUSE+=${BOOTGCC_SRC_URI:+" ada"}

#

#	BOOTGCC_SRC_URI

#			This variable specifies the SRC_URI value for the gcc binary image

#			for bootstrap, where the filename needs to start with "bootgcc-".

#			See comments in prepare_bootgcc() for how to create such images.

#			An example:

#					BOOTGCC_SRC_URI="

#						amd64? ( mirror://gentoo/bootgcc-4.4.7-amd64.tar.xz )

#						x86?   ( mirror://gentoo/bootgcc-4.4.7-x86.tar.xz   )

#					"

#			That is, in a native build, the bootgcc-* filename in $A, if any,

#			is used as the bootstrap compiler for your native ARCH.

	is_crosscompile || GCC_SRC_URI+="${BOOTGCC_SRC_URI:+ ${BOOTGCC_SRC_URI}}"

	unpack_bootgcc

unpack_bootgcc() {

	is_crosscompile && return 0

	tc-is-cross-compiler && return 0

	local a

	for a in ${A} ; do

		[[ ${a} == bootgcc-* ]] && unpack ${a}

		tc_version_is_at_least 4.8 && continue

		# support gnatboot images (c,ada) used by old gnatbuild.eclass

		[[ ${a} == gnatboot-* ]] && unpack ${a}

	done

}

	prepare_bootgcc

prepare_bootgcc() {

	local bootbin=

	local bootlib=

	if [[ -d ${WORKDIR}/etc/env.d/gcc ]] ; then

		#

		# How to create the bootstrap gcc binary image to be used here:

		#

		# $ USE="

		#       ada         # gnat needs Ada compiler for bootstrap (#547358)

		#       cxx         # >=gcc-4.8 needs C++ compiler for bootstrap

		#       -multilib   # needless for bootstrap (switch profile!)

		#       -nptl       # needless for bootstrap

		#       -openmp     # needless for bootstrap

		#       -anything   # needless for bootstrap

		#   " emerge --buildpkg =sys-devel/gcc-X.Y.Z-R

		#

		# $ bzip2 -dc /usr/portage/packages/sys-devel/gcc-X.Y.Z-R.tbz2 |

		#     xz -c -9 --extreme > bootgcc-X.Y.Z-R-ARCH.tar.xz

		#

		# For a new ARCH, you have to find out yourself where to get your

		# initial C,C++,Ada compiler from. Eventually there is an existing

		# one somewhere, or you have to cross-compile.

		#

		eval $(

			PATH=

			LDPATH=

			source "${WORKDIR}"/etc/env.d/gcc/*

			echo "bootbin='${WORKDIR}/${PATH##/}'"

			echo "bootlib='${WORKDIR}/${LDPATH##/}'"

		)

	elif [[ -d ${WORKDIR}/usr/lib/gnatgcc ]] ; then

		# <=gnatboot-4.1 image used by old gnatbuild.eclass

		bootbin=${WORKDIR}/usr/bin

		bootlib=$(echo "${WORKDIR}"/usr/lib/gnatgcc/*/*)

		if [[ -x ${bootbin}/gnatgcc_2wrap ]] ; then

			# gnatgcc wrapper script fails to properly quote args,

			# and we create wrappers anyway

			mv -f ${bootbin}/gnatgcc{_2wrap,} || die

		fi

	elif [[ -d ${WORKDIR}/usr/bin ]] ; then

		# >gnatboot-4.1 image used by old gnatbuild.eclass

		bootbin=${WORKDIR}/usr/bin

		bootlib=${WORKDIR}/usr/lib

	else

		#

		# nothing unpacked:

		# either we do cross compile, or there is no binary image for ARCH yet

		#

		return 0

	fi

	# Must not set tool variables into environment,

	# as they break the just-built stage compilers.

	_setup_bootgcc_tool() {

		local wrapdir=$1 envvar=$2 tool=$3 bootbin=$4 bootlib=$5

		mkdir -p "${wrapdir}" || die

		{

			echo "#! ${BASH}"

			echo "export CPATH='${bootlib}/include'"

			echo "export LIB_DIR='${bootlib}'"

			echo "export LDFLAGS='-L${bootlib}'"

			echo "export LIBRARY_PATH='${bootlib}'"

			echo "export ADA_OBJECTS_PATH='${bootlib}/adalib'"

			echo "export ADA_INCLUDE_PATH='${bootlib}/adainclude'"

			# need to find cc1, cc1plus, gnat1, ...

			echo "export PATH='${bootbin}:${PATH}'"

			echo "exec '${bootbin}/${tool}' \"\${@}\""

		} > "${wrapdir}/${tool}" || die

		chmod +x "${wrapdir}/${tool}" || die

		export ${envvar}=${wrapdir}/${tool}

	}

	local wrapdir=${WORKDIR}/bootgcc

	local wraplist=(

		CPP       cpp

		CC        gcc

		CXX       g++

		# do we really need all of them? more?

		GNATBIND  gnatbind

		GNATCHOP  gnatchop

		GNATCLEAN gnatclean

		GNATFIND  gnatfind

		GNATKR    gnatkr

		GNATLINK  gnatlink

		GNATLS    gnatls

		GNATMAKE  gnatmake

		GNATMEM   gnatmem

		GNATPREP  gnatprep

		GNATSYM   gnatsym

		GNATXREF  gnatxref

	)

	local i var tool

	for ((i = 0; i < ${#wraplist[@]}; i += 2)) ; do

		var=${wraplist[i]}

		tool=${wraplist[i + 1]}

		if [[ -x ${bootbin}/${tool} ]] ; then

			_setup_bootgcc_tool "${wrapdir}" ${var} "${tool}" "${bootbin}" "${bootlib}"

		elif [[ ${tool} != gnat* && -x ${bootbin}/gnat${tool} ]] ; then

			# gnatcpp,gnatgcc,gnatg++ in image used by old gnatbuild.eclass

			_setup_bootgcc_tool "${wrapdir}" ${var} "gnat${tool}" "${bootbin}" "${bootlib}"

		fi

	done

	# some (older) gcc do not use (enough) GNAT-tool environment vars

	export PATH=${wrapdir}:${PATH}

}

	if is_ada ; then

		GCC_LANG+=",ada"

		confgcc+=( --enable-libada )

	fi