# 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.ebuild,v 1.3 2007/04/06 16:26:05 cparrott Exp $

# Brief explanation of the bootstrap logic:
#
# ghc requires ghc-bin to bootstrap.
# Therefore, 
# (1) both ghc-bin and ghc provide virtual/ghc
# (2) virtual/ghc *must* default to ghc-bin
# (3) ghc depends on virtual/ghc
#
# This solution has the advantage that the binary distribution
# can be removed once an forall after the first succesful install
# of 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="http://haskell.org/ghc/dist/${EXTRA_SRC_URI}/${MY_P}-src.tar.bz2"
#	"test? ( http://haskell.org/ghc/dist/${EXTRA_SRC_URI}/ghc-testsuite-${MY_PV}.tar.gz )"

LICENSE="as-is"
SLOT="0"
KEYWORDS="~alpha ~amd64 ~hppa ~ia64 ~ppc ~ppc64 ~sparc ~x86 ~x86-fbsd"
IUSE="doc"

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-4.2"

# ghc cannot usually be bootstrapped using later versions ...
DEPEND="${RDEPEND}
	<virtual/ghc-6.7
	!>=virtual/ghc-6.7
	doc? (  ~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-1.1.6.1"

#pkg_setup() {
	# Portage's resolution of virtuals fails on virtual/ghc in some Portage
	# releases, the following function causes the build to fail with an
	# informative error message in such a case.
	#if ! has_version virtual/ghc; then
	#	eerror "This ebuild needs a version of GHC to bootstrap from."
	#	eerror "Please emerge dev-lang/ghc-bin to get a binary version."
	#	eerror "You can either use the binary version directly or emerge"
	#	eerror "dev-lang/ghc afterwards."
	#	die "virtual/ghc version required to build"
	#fi
#}

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=\"$(ghc-libdir)/ghc-$1\";"
	echo "TOPDIROPT=\"-B$(ghc-libdir)\";"
	echo "GHC_CFLAGS=\"${GHC_CFLAGS}\";"
	echo '# Mini-driver for GHC'
	echo 'exec $GHCBIN $TOPDIROPT $GHC_CFLAGS ${1+"$@"}'
}

src_unpack() {
	base_src_unpack
	ghc_setup_cflags

	# 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"

	# 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"
}

src_compile() {
	# 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

	GHC_CFLAGS="" ghc_setup_wrapper $(ghc-version) > "${T}/ghc.sh"
	chmod +x "${T}/ghc.sh"

	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 ?

}

src_install () {
	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
}

pkg_postinst () {
	ebegin "Hiding ghc's built-in cabal "
	$(ghc-getghcpkg) hide Cabal > /dev/null
	eend $?
	ghc-reregister
	elog "If you have dev-lang/ghc-bin installed, you might"
	elog "want to unmerge it. It is no longer needed."
	elog
	ewarn "IMPORTANT:"
	ewarn "If you have upgraded from another version of ghc or"
	ewarn "if you have switched from ghc-bin to ghc, please run:"
	ewarn "	/usr/sbin/ghc-updater"
	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
#}