# Copyright 1999-2007 Gentoo Foundation
# Distributed under the terms of the GNU General Public License v2
# $Header: /var/cvsroot/gentoo-x86/dev-lang/ghc/ghc-6.6.1.ebuild,v 1.2 2007/07/08 16:21:46 dcoutts Exp $

# Brief explanation of the bootstrap logic:
#
# Previous ghc ebuilds have been split into two: ghc and ghc-bin,
# where ghc-bin was primarily used for bootstrapping purposes.
# From now on, these two ebuilds have been combined, with the
# binary USE flag used to determine whether or not the pre-built
# binary package should be emerged or whether ghc should be compiled
# from source.  If the latter, then the relevant ghc-bin for the
# arch in question will be used in the working directory to compile
# ghc from source.
#
# This solution has the advantage of allowing us to retain the one
# ebuild for both packages, and thus phase out virtual/ghc.

# Note to users of hardened gcc-3.x:
#
# If you emerge ghc with hardened gcc it should work fine (because we
# turn off the hardened features that would otherwise break ghc).
# However, emerging ghc while using a vanilla gcc and then switching to
# hardened gcc (using gcc-config) will leave you with a broken ghc. To
# fix it you would need to either switch back to vanilla gcc or re-emerge
# ghc (or ghc-bin). Note that also if you are using hardened gcc-3.x and
# you switch to gcc-4.x that this will also break ghc and you'll need to
# re-emerge ghc (or ghc-bin). People using vanilla gcc can switch between
# gcc-3.x and 4.x with no problems.

inherit base eutils flag-o-matic toolchain-funcs ghc-package check-reqs

DESCRIPTION="The Glasgow Haskell Compiler"
HOMEPAGE="http://www.haskell.org/ghc/"

# discover if this is a snapshot release
IS_SNAPSHOT="${PV%%*pre*}" # zero if snapshot
MY_PV="${PV/_pre/.}"
MY_P="${PN}-${MY_PV}"
EXTRA_SRC_URI="${MY_PV}"
[[ -z "${IS_SNAPSHOT}" ]] && EXTRA_SRC_URI="current/dist"

SRC_URI="!binary? ( http://haskell.org/ghc/dist/${EXTRA_SRC_URI}/${MY_P}-src.tar.bz2 )
		 amd64?	( mirror://gentoo/ghc-bin-${PV}-amd64.tbz2 )
		 x86?	( mirror://gentoo/ghc-bin-${PV}-x86.tbz2 )"
#		 ppc?	( mirror://gentoo/ghc-bin-${PV}-ppc.tbz2 )
#		 alpha?	( mirror://gentoo/ghc-bin-${PV}-alpha.tbz2 )
#		 sparc?	( mirror://gentoo/ghc-bin-${PV}-sparc.tbz2 )"
#	"test? ( http://haskell.org/ghc/dist/${EXTRA_SRC_URI}/ghc-testsuite-${MY_PV}.tar.gz )"

LICENSE="BSD"
SLOT="0"
KEYWORDS="~alpha ~amd64 ~x86"
#KEYWORDS="~alpha ~amd64 ~hppa ~ia64 ~ppc ~ppc64 ~sparc ~x86 ~x86-fbsd"
IUSE="binary doc ghcbootstrap"

LOC="/opt/ghc" # location for installation of binary version
S="${WORKDIR}/${MY_P}"

PROVIDE="virtual/ghc"

RDEPEND="
	>=sys-devel/gcc-2.95.3
	>=dev-lang/perl-5.6.1
	>=dev-libs/gmp-4.1
	=sys-libs/readline-5*"

DEPEND="${RDEPEND}
	doc? ( !binary? (
			~app-text/docbook-xml-dtd-4.2
			app-text/docbook-xsl-stylesheets
			>=dev-libs/libxslt-1.1.2
			>=dev-haskell/haddock-0.8 ) )"

PDEPEND=">=dev-haskell/cabal-1.1.6.2"

append-ghc-cflags() {
	local flag compile assemble link
	for flag in $*; do
		case ${flag} in
			compile)	compile="yes";;
			assemble)	assemble="yes";;
			link)		link="yes";;
			*)
				[[ ${compile}  ]] && GHC_CFLAGS="${GHC_CFLAGS} -optc${flag}"
				[[ ${assemble} ]] && GHC_CFLAGS="${GHC_CFLAGS} -opta${flag}"
				[[ ${link}     ]] && GHC_CFLAGS="${GHC_CFLAGS} -optl${flag}";;
		esac
	done
}

ghc_setup_cflags() {
	# We need to be very careful with the CFLAGS we ask ghc to pass through to
	# gcc. There are plenty of flags which will make gcc produce output that
	# breaks ghc in various ways. The main ones we want to pass through are
	# -mcpu / -march flags. These are important for arches like alpha & sparc.
	# We also use these CFLAGS for building the C parts of ghc, ie the rts.
	strip-flags
	strip-unsupported-flags
	filter-flags -fPIC

	GHC_CFLAGS=""
	for flag in ${CFLAGS}; do
		case ${flag} in

			# Ignore extra optimisation (ghc passes -O to gcc anyway)
			# -O2 and above break on too many systems
			-O*) ;;

			# Arch and ABI flags are what we're really after
			-m*) append-ghc-cflags compile assemble ${flag};;

			# Debugging flags don't help either. You can't debug Haskell code
			# at the C source level and the mangler discards the debug info.
			-g*) ;;

			# Ignore all other flags, including all -f* flags
		esac
	done

	# hardened-gcc needs to be disabled, because the mangler doesn't accept
	# its output.
	gcc-specs-pie && append-ghc-cflags compile link	-nopie
	gcc-specs-ssp && append-ghc-cflags compile		-fno-stack-protector

	# We also add -Wa,--noexecstack to get ghc to generate .o files with
	# non-exectable stack. This it a hack until ghc does it itself properly.
	append-ghc-cflags assemble		"-Wa,--noexecstack"
}

ghc_setup_wrapper() {
	echo '#!/bin/sh'
	echo "GHCBIN=\"$1\";"
	echo "TOPDIROPT=\"-B$(dirname $1)\";"
	echo "GHC_CFLAGS=\"${GHC_CFLAGS}\";"
	echo '# Mini-driver for GHC'
	echo 'exec $GHCBIN $TOPDIROPT $GHC_CFLAGS ${1+"$@"}'
}

pkg_setup() {
	if use ghcbootstrap && [[ -z $(type -P ghc) ]]; then
		ewarn ""
		ewarn "You requested bootstrapping,"
		ewarn "but I could not find a ghc executable to bootstrap with"
		ewarn ""
		die "Could not find a ghc executable to bootstrap with"
	fi
}

src_unpack() {
	# Create the ${S} dir if we're using the binary version
	use binary && mkdir "${S}"

	base_src_unpack
	ghc_setup_cflags

	if use binary; then

		# Move unpacked files to the expected place
		mv "${WORKDIR}/usr" "${S}"

		# Setup the ghc wrapper script
		GHCBIN="${LOC}/$(get_libdir)/$P/$P"
		ghc_setup_wrapper "$GHCBIN" > "${S}/usr/bin/ghc-${PV}"

		# Relocate from /usr to /opt/ghc
		sed -i -e "s|/usr|${LOC}|g" \
			"${S}/usr/bin/ghci-${PV}" \
			"${S}/usr/bin/ghc-pkg-${PV}" \
			"${S}/usr/bin/hsc2hs" \
			"${S}/usr/$(get_libdir)/ghc-${PV}/package.conf"

		sed -i -e "s|/usr/$(get_libdir)|${LOC}/$(get_libdir)|" \
			"${S}/usr/bin/ghcprof"

	else

		# Modify the ghc driver script to use GHC_CFLAGS
		echo "SCRIPT_SUBST_VARS += GHC_CFLAGS" >> "${S}/driver/ghc/Makefile"
		echo "GHC_CFLAGS = ${GHC_CFLAGS}"      >> "${S}/driver/ghc/Makefile"
		sed -i -e 's|$TOPDIROPT|$TOPDIROPT $GHC_CFLAGS|' "${S}/driver/ghc/ghc.sh"

		# Create the setup wrapper
		if use ghcbootstrap; then
			# When we are bootstrapping, rely on the developer to have set a
			# sane environment

			echo -e '#!/bin/sh\nexec ghc $*' > "${T}/ghc.sh"
		else
			GHC_TOP="${WORKDIR}/usr/$(get_libdir)/${P}"
			GHC_CFLAGS="" ghc_setup_wrapper "${GHC_TOP}/${P}" > "${T}/ghc.sh"

			# Fix paths for workdir ghc
			sed -i -e "s|/usr|${WORKDIR}/usr|g" \
				"${GHC_TOP}/package.conf"
		fi

		chmod +x "${T}/ghc.sh"

		# If we're using the testsuite then move it to into the build tree
		#	use test && mv "${WORKDIR}/testsuite" "${S}/"

		# This is a hack for ia64. We can persuade ghc to avoid mangler errors
		# if we turn down the optimisations in one problematic module.
		use ia64 && sed -i -e 's/OPTIONS_GHC/OPTIONS_GHC -O0 -optc-O/' \
			"${S}/libraries/base/GHC/Float.lhs"

		# Don't strip binaries on install. See QA warnings in bug #140369.
		sed -i -e 's/SRC_INSTALL_BIN_OPTS	+= -s//' ${S}/mk/config.mk.in

		# Temporary patches that needs testing before being pushed upstream:
#		cd "${S}"
		# Fix sparc split-objs linking problem
#		epatch "${FILESDIR}/ghc-6.5-norelax.patch"

		# Disable threaded runtime build to work around RTS bugs on sparc
#		epatch "${FILESDIR}/ghc-6.6-nothreadedrts.patch"

	fi
}

src_compile() {
	if ! use binary; then

		# initialize build.mk
		echo '# Gentoo changes' > mk/build.mk

		# We also need to use the GHC_CFLAGS flags when building ghc itself
		echo "SRC_HC_OPTS+=${GHC_CFLAGS}" >> mk/build.mk
		echo "SRC_CC_OPTS+=${CFLAGS} -Wa,--noexecstack" >> mk/build.mk

		# If you need to do a quick build then enable this bit and add debug to IUSE
		#if use debug; then
		#	echo "SRC_HC_OPTS     = -H32m -O -fasm" >> mk/build.mk
		#	echo "GhcLibHcOpts    =" >> mk/build.mk
		#	echo "GhcLibWays      =" >> mk/build.mk
		#	echo "SplitObjs       = NO" >> mk/build.mk
		#fi

		# determine what to do with documentation
		if use doc; then
		  echo XMLDocWays="html" >> mk/build.mk
		else
		  echo XMLDocWays="" >> mk/build.mk
		  # needed to prevent haddock from being called
		  echo NO_HADDOCK_DOCS=YES >> mk/build.mk
		fi

		# circumvent a very strange bug that seems related with ghc producing too much
		# output while being filtered through tee (e.g. due to portage logging)
		# reported as bug #111183
		echo "SRC_HC_OPTS+=-fno-warn-deprecations" >> mk/build.mk

		# force the config variable ArSupportsInput to be unset;
		# ar in binutils >= 2.14.90.0.8-r1 seems to be classified
		# incorrectly by the configure script
		echo "ArSupportsInput:=" >> mk/build.mk

		# Some arches do support some ghc features even though they're off by default
		use ia64 && echo "GhcWithInterpreter=YES" >> mk/build.mk

		# Workaround for threaded RTS bugs on sparc in ghc-6.6
		# This is rather draconian, hopefully upstream fixes this soon.
		if use sparc; then
		  echo "GhcUnregisterised=YES" >> mk/build.mk
		  echo "GhcWithNativeCodeGen=NO" >> mk/build.mk
		  echo "GhcWithInterpreter=NO" >> mk/build.mk
		  echo "SplitObjs=NO" >> mk/build.mk
		  echo "GhcRTSWays := debug" >> mk/build.mk
		  echo "GhcNotThreaded=YES" >> mk/build.mk
		fi

		# The SplitObjs feature makes 'ar'/'ranlib' take loads of RAM:
		CHECKREQS_MEMORY="200"
		if ! check_reqs_conditional; then
		  elog "Turning off ghc's 'Split Objs' feature because this machine"
		  elog "does not have enough RAM for it. This will have the effect"
		  elog "of making binaries produced by ghc considerably larger."
		  echo "SplitObjs=NO" >> mk/build.mk
		fi

		econf \
		  --with-ghc="${T}/ghc.sh" \
		  || die "econf failed"

		emake all datadir="/usr/share/doc/${PF}" || die "make failed"
		# the explicit datadir is required to make the haddock entries
		# in the package.conf file point to the right place ...
		# TODO: is this still required ?

	fi # ! use binary
}

src_install () {
	if use binary; then
	  mkdir "${D}/opt"
	  mv "${S}/usr" "${D}/opt/ghc"

	  # Remove the docs if not requested
	  use doc || rm -rf "${D}/opt/ghc/share/doc/${P}/html"

	  doenvd "${FILESDIR}/10ghc"
	else
	  local insttarget

	  insttarget="install"
	  use doc && insttarget="${insttarget} install-docs"

	  # the libdir0 setting is needed for amd64, and does not
	  # harm for other arches
	  #TODO: is this still required?
	  emake -j1 ${insttarget} \
		  prefix="${D}/usr" \
		  datadir="${D}/usr/share/doc/${PF}" \
		  infodir="${D}/usr/share/info" \
		  mandir="${D}/usr/share/man" \
		  libdir0="${D}/usr/$(get_libdir)" \
		  || die "make ${insttarget} failed"

	  #need to remove ${D} from ghcprof script
	  # TODO: does this actually work?
	  cd "${D}/usr/bin"
	  mv ghcprof ghcprof-orig
	  sed -e 's:$FPTOOLS_TOP_ABS:#$FPTOOLS_TOP_ABS:' ghcprof-orig > ghcprof
	  chmod a+x ghcprof
	  rm -f ghcprof-orig

	  cd "${S}"
	  dodoc README ANNOUNCE LICENSE VERSION

	  dosbin ${FILESDIR}/ghc-updater
	fi
}

pkg_postinst () {
	ghc-reregister
	elog "If you have dev-lang/ghc-bin installed, you might"
	elog "want to unmerge it. It is no longer needed."
	elog

	if use binary; then
		elog "The envirenment has been set to use the binary distribution of"
		elog "GHC. In order to activate it please run:"
		elog "   env-update && source /etc/profile"
		elog "Otherwise this setting will become active the next time you login"
	fi

	ewarn "IMPORTANT:"
	ewarn "If you have upgraded from another version of ghc or"
	ewarn "if you have switched between binary and source versions"
	ewarn "of ghc, please run:"
	if use binary; then
		ewarn "      /opt/ghc/sbin/ghc-updater"
	else
		ewarn "      /usr/sbin/ghc-updater"
	fi
	ewarn "to re-merge all ghc-based Haskell libraries."
}

#src_test() {
#	if use test; then
#		local summary
#		summary="${T}/testsuite-summary.txt"
#
#		make -C "${S}/testsuite/" boot || die "Preparing the testsuite failed"
#		make -C "${S}/testsuite/tests/ghc-regress" \
#				TEST_HC="${S}/ghc/compiler/stage2/ghc-inplace" \
#				EXTRA_RUNTEST_OPTS="--output-summary=${summary}"
#
#		if grep -q ' 0 unexpected failures' "${summary}"; then
#			einfo "All tests passed ok"
#		else
#			ewarn "Some tests failed, for a summary see: ${summary}"
#		fi
#	else
#		ewarn "Sadly, due to some portage limitations you need both"
#		ewarn "USE=test and FEATURES=test to run the ghc testsuite"
#	fi
#}