dev-lang/ghc: bump up to 8.8.1. no KEYWORDS yet

Package-Manager: Portage-2.3.76, Repoman-2.3.17 Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org>
2026-09-24 17:09:10 -07:00 · 2019-10-04 07:46:34 +01:00
parent 2db6835d5b
commit 8ff3b28cba
6 changed files with 915 additions and 0 deletions
--- a/dev-lang/ghc/Manifest
+++ b/dev-lang/ghc/Manifest
@@ -12,6 +12,8 @@ DIST ghc-8.6.4-src.tar.xz 19029904 BLAKE2B 80676923866417cbf674c3cfadc2ecf9a673e
 DIST ghc-8.6.4-testsuite.tar.xz 1906656 BLAKE2B b0e55b415c885479c3573fe86436338971e685edc95e106043f36e92e1ee6a7e86add9e86a35c8bd685916f18a7bcf08d4a7b845da41dd855132b131ccbc4a37 SHA512 b1bbe1759ec528914cbfa6b3789c596e46b6266568972b9f5d1cf13e31b7206400b65536e7acea698161e46b8ca11285b3282ebd9336d23b68d34feb4f0bf314
 DIST ghc-8.6.5-src.tar.xz 19092168 BLAKE2B 2ac0926b186c43fd179170a0690492129e9ffb6651608875db7167113becf324dcf99a82f56e578c67051f813007c0ffa32ca5b12588f0d370330c8274a2d74d SHA512 c08a7480200cb99e1ffbe4ce7669f552b1054054966f7e7efcbc5f98af8032e1249fa391c4fc4c7d62cc8e0be5d17fa05845177f3cea3dbcf86e6c92d40fc0f9
 DIST ghc-8.6.5-testsuite.tar.xz 1910060 BLAKE2B 71136207e3eccb4ec6756661ffa64c0a82475704c071cd8f060855a9f40d7d1fc4be2da7ff265df38fb918b8ee2ce21a54ee4b224aacaa3026ad1ddb1e1e4ab2 SHA512 980f3934bb18876cc80b80a0eb64a9ca1dfaa7f4d8b0761f5d733a6583053e38b231445388b992b26ec1ad5f569b6385dbe60f96381794f5577964979c253e16
+DIST ghc-8.8.1-src.tar.xz 28634672 BLAKE2B 3a012db5d9798efddf806542a88cd9fef1d0972f7f025d377c247961cf8d8071fcf390aa130ac11f1a5556fb572499b9288a8698c49bbd594f0bb5fec4130a2f SHA512 7268b012c3a6c34e7eac05c7d6959de6005651d33e870860bbfe589295502e8794a76580130b8f4da2f88032b68116dbbdbc4c1e900e0c862aaa9891fa788bef
+DIST ghc-8.8.1-testsuite.tar.xz 1959220 BLAKE2B 8606a6439f7d5b4c837b2325c4ef5705dbcea17c4b59daf7aafd0de68e55179bb2c03ce7a4f376398b185b6dbfb361d18592756558461ee43722d2142370d815 SHA512 e13b651c60deb86522efbfe8aa42679cc81a413475f70580d9ef28dbb711617c523951441a30fb46f3be9418c4c0bb4dbc522b04aaa51313afd2d39027696c30
 DIST ghc-bin-7.10.3-alpha.tbz2 183558856 BLAKE2B 2bb02aafa49c6a91bec016e8bec2d07257d602e53c9df55792ec6fbbf8e2e46de1d5f3f72c0ccf74d6bd7f7987f53412063ccb02ae85455fce11fa928cbf5291 SHA512 08709fe9b4036ab41715c9a637a2a160104e3ab9e0ed9efaaf73428e3cfe19619e50c42b72c60bbbd27be2b9c2ea68f63d72c1a27d4519756e7c0d909f724230
 DIST ghc-bin-7.10.3-amd64.tbz2 112040431 BLAKE2B 3e59b70ca309a1cd704266c54a7983f9a58362bf700ced89c5649c780c664c650ec091e14026a7b84e339d2ebff39eba1772eebcd9fb4b99b9c99d179453d5cc SHA512 e1554b3944edbe8e16537de5a29132dc6a22d780d9a700cdc9b76387b94191164398d6f2242bf8199527802572e2bb02545569d4f0930a0ee0dbfdeb25978558
 DIST ghc-bin-7.10.3-ia64.tbz2 238680956 BLAKE2B 08593718d376051edfb0c86131e54dafc5c15056757fbeef90c653a7d217e49ff34ffaf7cd4083144c9277e73a290b822a0f889aaf806341375708e4b92654b2 SHA512 3694011aec8a6dc37889418b318993cb82f9b46a5175dd837713f396c8f59a19a920e0b0669fe3b4ec37d5bd8837c115264c0a8fc97c5a4ce06a3bdd52fcfce5
@@ -47,5 +49,7 @@ DIST ghc-bin-8.6.4-i686-pc-linux-gnu.tbz2 121639881 BLAKE2B 51d223b654ff23bbdd59
 DIST ghc-bin-8.6.4-x86_64-pc-linux-gnu.tbz2 121695747 BLAKE2B 39c745f5f9946bbae622e09bbdabdde4d62eec472fe14e693f37cba6b93ff66e4e56f66df8f0f073686339d252dce71f79f4c2aaef620c3dffbc26a67b1119c3 SHA512 c60bac50e7879bda1d6dcc7c1f12fdac915b18c3ebbfcfad575b2b01fcb57a487496ce7935f7ee4ae934162209ab66370fbcc8a4f021628e5f9a2aa7ef95e119
 DIST ghc-bin-8.6.5-i686-pc-linux-gnu.tbz2 121938050 BLAKE2B 17b6d15af21390e28a025505da76d39a2f8656f74c88a81fc75e7c8e799e54171c0d964d8a977c01576603a781c139b5363ea79eeaa2252622913d2a08a79f0e SHA512 9eb33b4670ee15f53c988885a119f3ef7be896ddcb318019628cdd04e21ec0c61876e08466d9d10d6cb1e16d89cd318e0ba42f0f0ae512f48590fe87483739cd
 DIST ghc-bin-8.6.5-x86_64-pc-linux-gnu.tbz2 121728723 BLAKE2B 6620b2a116b5696dd2d776350a43251c093e117338a4407ae8c41ae27763a4614d7e761b2684b90aa9317dafe7cb67481a6bc141c812d335d5231724ae3db2a7 SHA512 69681eab137f6713339f8912d0d92f6af865630053bcd7a32cb8a31e01628e969951db976533196794fe39e0e57f0fcd8778d9fc9fed4f4231e965b9a603dd8e
+DIST ghc-bin-8.8.1-i686-pc-linux-gnu.tbz2 120789855 BLAKE2B 386f37696d956078fad5cad50cbf5b9d9d7765615a1d9cc91a376fb5394648afe8ca956e24ef210f2ff0e51f339b63b16a50f6dc35f30babf019aa57de50b27b SHA512 193c29889693befba863d3c5a26d38d8182bb7e1932b61115dc0a21b6582f818b05db144a9fae5aee06af2044ea59f884825cf1081b62a1c67feb3041d184d3a
+DIST ghc-bin-8.8.1-x86_64-pc-linux-gnu.tbz2 119317594 BLAKE2B 98f0fb262ac485dcfd6a8a67304912ffad2bf2634111fcc3b60346697a836867006bbacaab1e1be0cd5be34b4595d12bec13af644c451c10f7e3843ebaf5922f SHA512 e6acb11755db18fd86a346de642b8579a6b48b303c19795949757f5e351ad3b8892906e989dc57a7fd4471d0efe30fc8175df5bac741d7faecfe42a855a67980
 DIST hoopl-3.10.2.0.tar.gz 241940 BLAKE2B 0ed7bf80486767c81415f99da8780a525401c388dea0b3f380bbecceae9cc7f66d8b5d0d7b31f8cb41796309b7a93adb113485efd14882f8af321989ce900a9b SHA512 083baa8a5eb53247aff8d5b9b2144e0f63adb9400934297bbd80bfcec607dd90a34def4301045a60472ef10b0fb90ab84692fc08f786e7f806c28afdab1ef66a
 DIST transformers-0.4.3.0.tar.gz 28632 BLAKE2B 92cabcb654bb11854a3bffbb1262f5cd62eda1aff447157086a61ebc451ebf2fddec53b6a2cc058174f24f0f0e32df671d3717e30a542c8dc90cb87e327d990c SHA512 c3ec0893ebba4fbd6087c3202e919552c4a9bff3350b5c0589e7ebb18751a515d98b8cac15b0a3252906ea72b5a0eb09b7fe88c8da88b09d6ce4fbf0f50b2780
--- a/dev-lang/ghc/files/ghc-8.6.5-numa.patch
+++ b/dev-lang/ghc/files/ghc-8.6.5-numa.patch
@@ -0,0 +1,22 @@
+Disable automagic NUMA linking.
+
+Reported-by: Sergey Alirzaev
+Bug: https://github.com/gentoo-haskell/gentoo-haskell/issues/955
+--- a/configure.ac
+++ b/configure.ac
+@@ -1264,10 +1264,14 @@ dnl ** Have libnuma?
+ dnl --------------------------------------------------------------
+ HaveLibNuma=0
+ AC_CHECK_HEADERS([numa.h numaif.h])
+-
+ if test "$ac_cv_header_numa_h$ac_cv_header_numaif_h" = "yesyes" ; then
+     AC_CHECK_LIB(numa, numa_available,HaveLibNuma=1)
+ fi
+AC_ARG_ENABLE(numa,
+    [AC_HELP_STRING([--enable-numa],
+        [Enable NUMA thread balancing support in the runtime system via numactl's libnuma [default=auto]])])
+AS_IF([test "x$enable_numa" = "xno"], [HaveLibNuma=0])
+
+ AC_DEFINE_UNQUOTED([HAVE_LIBNUMA], [$HaveLibNuma], [Define to 1 if you have libnuma])
+ if test $HaveLibNuma = "1" ; then
+   AC_SUBST([CabalHaveLibNuma],[True])
--- a/dev-lang/ghc/files/ghc-8.8.1-no-alex.patch
+++ b/dev-lang/ghc/files/ghc-8.8.1-no-alex.patch
@@ -0,0 +1,33 @@
+https://github.com/gentoo-haskell/gentoo-haskell/issues/959
+
+From 144abba394c6a23eb877fbde727111a5e75b9d47 Mon Sep 17 00:00:00 2001
+From: Ben Gamari <ben@smart-cactus.org>
+Date: Wed, 18 Sep 2019 23:50:20 -0400
+Subject: [PATCH] configure: Don't depend upon alex in source dist build
+
+This fixes #16860 by verifying that the generated sources don't already
+exist before asserting that the `alex` executable was found. This
+replicates the logic already used for `happy` in the case of `alex`.
+---
+ aclocal.m4 | 7 +++++--
+ 1 file changed, 5 insertions(+), 2 deletions(-)
+
+--- a/aclocal.m4
+++ b/aclocal.m4
+@@ -984,8 +984,11 @@ else
+ fi;
+ changequote([, ])dnl
+ ])
+-FP_COMPARE_VERSIONS([$fptools_cv_alex_version],[-lt],[3.1.7],
+-  [AC_MSG_ERROR([Alex version 3.1.7 or later is required to compile GHC.])])[]
+if test ! -f compiler/parser/Lexer.hs
+then
+    FP_COMPARE_VERSIONS([$fptools_cv_alex_version],[-lt],[3.1.7],
+      [AC_MSG_ERROR([Alex version 3.1.7 or later is required to compile GHC.])])[]
+fi
+ AlexVersion=$fptools_cv_alex_version;
+ AC_SUBST(AlexVersion)
+ ])
+-- 
+2.23.0
+
--- a/dev-lang/ghc/files/ghc-8.8.1-revert-CPP.patch
+++ b/dev-lang/ghc/files/ghc-8.8.1-revert-CPP.patch
@@ -0,0 +1,52 @@
+Don't pass CPP options. Otherwise ghc-8.8.1 can't build itself.
+Eventually ghc will fix it's headers at propagate defines.
+
+https://gitlab.haskell.org/ghc/ghc/commit/cfd3e0f1cfd16c8f35cae139d2a871a32eb4d2e1
+https://gitlab.haskell.org/ghc/ghc/issues/17146
+
+--- a/compiler/main/DriverPipeline.hs
+++ b/compiler/main/DriverPipeline.hs
+@@ -1190,6 +1190,9 @@ runPhase (RealPhase Cmm) input_fn dflags
+ -----------------------------------------------------------------------------
+ -- Cc phase
+ 
+-- we don't support preprocessing .c files (with -E) now.  Doing so introduces
+-- way too many hacks, and I can't say I've ever used it anyway.
+
+ runPhase (RealPhase cc_phase) input_fn dflags
+    | any (cc_phase `eqPhase`) [Cc, Ccxx, HCc, Cobjc, Cobjcxx]
+    = do
+@@ -1211,16 +1214,6 @@ runPhase (RealPhase cc_phase) input_fn dflags
+               (includePathsQuote cmdline_include_paths)
+         let include_paths = include_paths_quote ++ include_paths_global
+ 
+-        -- pass -D or -optP to preprocessor when compiling foreign C files
+-        -- (#16737). Doing it in this way is simpler and also enable the C
+-        -- compiler to performs preprocessing and parsing in a single pass,
+-        -- but it may introduce inconsistency if a different pgm_P is specified.
+-        let more_preprocessor_opts = concat
+-              [ ["-Xpreprocessor", i]
+-              | not hcc
+-              , i <- getOpts dflags opt_P
+-              ]
+-
+         let gcc_extra_viac_flags = extraGccViaCFlags dflags
+         let pic_c_flags = picCCOpts dflags
+ 
+@@ -1230,7 +1223,7 @@ runPhase (RealPhase cc_phase) input_fn dflags
+         -- hc code doesn't not #include any header files anyway, so these
+         -- options aren't necessary.
+         pkg_extra_cc_opts <- liftIO $
+-          if hcc
+          if cc_phase `eqPhase` HCc
+              then return []
+              else getPackageExtraCcOpts dflags pkgs
+ 
+@@ -1312,7 +1305,6 @@ runPhase (RealPhase cc_phase) input_fn dflags
+                        ++ [ "-include", ghcVersionH ]
+                        ++ framework_paths
+                        ++ include_paths
+-                       ++ more_preprocessor_opts
+                        ++ pkg_extra_cc_opts
+                        ))
+ 
--- a/dev-lang/ghc/ghc-8.8.1.ebuild
+++ b/dev-lang/ghc/ghc-8.8.1.ebuild
@@ -0,0 +1,801 @@
+# Copyright 1999-2019 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=7
+
+# to make make a crosscompiler use crossdev and symlink ghc tree into
+# cross overlay. result would look like 'cross-sparc-unknown-linux-gnu/ghc'
+export CBUILD=${CBUILD:-${CHOST}}
+export CTARGET=${CTARGET:-${CHOST}}
+if [[ ${CTARGET} = ${CHOST} ]] ; then
+	if [[ ${CATEGORY/cross-} != ${CATEGORY} ]] ; then
+		export CTARGET=${CATEGORY/cross-}
+	fi
+fi
+
+inherit autotools bash-completion-r1 eutils flag-o-matic ghc-package
+inherit multilib multiprocessing pax-utils toolchain-funcs prefix
+inherit check-reqs
+DESCRIPTION="The Glasgow Haskell Compiler"
+HOMEPAGE="http://www.haskell.org/ghc/"
+
+# we don't have any binaries yet
+arch_binaries=""
+
+BIN_PV=${PV}
+# sorted!
+#arch_binaries="$arch_binaries alpha? ( https://slyfox.uni.cx/~slyfox/distfiles/ghc-bin-${PV}-alpha.tbz2 )"
+#arch_binaries="$arch_binaries arm? ( https://slyfox.uni.cx/~slyfox/distfiles/ghc-bin-${PV}-armv7a-hardfloat-linux-gnueabi.tbz2 )"
+#arch_binaries="$arch_binaries arm64? ( https://slyfox.uni.cx/~slyfox/distfiles/ghc-bin-${PV}-aarch64-unknown-linux-gnu.tbz2 )"
+arch_binaries="$arch_binaries amd64? ( https://slyfox.uni.cx/~slyfox/distfiles/ghc-bin-${PV}-x86_64-pc-linux-gnu.tbz2 )"
+#arch_binaries="$arch_binaries ia64?  ( https://slyfox.uni.cx/~slyfox/distfiles/ghc-bin-${PV}-ia64-fixed-fiw.tbz2 )"
+#arch_binaries="$arch_binaries ppc? ( https://slyfox.uni.cx/~slyfox/distfiles/ghc-bin-${PV}-ppc.tbz2 )"
+#arch_binaries="$arch_binaries ppc64? ( https://slyfox.uni.cx/~slyfox/distfiles/ghc-bin-${PV}-ppc64.tbz2 )"
+#arch_binaries="$arch_binaries sparc? ( https://slyfox.uni.cx/~slyfox/distfiles/ghc-bin-${PV}-sparc.tbz2 )"
+arch_binaries="$arch_binaries x86? ( https://slyfox.uni.cx/~slyfox/distfiles/ghc-bin-${PV}-i686-pc-linux-gnu.tbz2 )"
+
+# various ports:
+#arch_binaries="$arch_binaries x86-fbsd? ( https://slyfox.uni.cx/~slyfox/distfiles/ghc-bin-${PV}-x86-fbsd.tbz2 )"
+
+# 0 - yet
+yet_binary() {
+	case "${ARCH}" in
+		#alpha) return 0 ;;
+		#arm64) return 0 ;;
+		#arm) return 0 ;;
+		amd64) return 0 ;;
+		#ia64) return 0 ;;
+		#ppc) return 0 ;;
+		#ppc64) return 0 ;;
+		#sparc) return 0 ;;
+		x86) return 0 ;;
+		*) return 1 ;;
+	esac
+}
+
+GHC_PV=${PV}
+#GHC_PV=8.6.0.20180810 # uncomment only for -alpha, -beta, -rc ebuilds
+GHC_P=${PN}-${GHC_PV} # using ${P} is almost never correct
+
+SRC_URI="!binary? (
+	http://downloads.haskell.org/~ghc/${PV/_/-}/${GHC_P}-src.tar.xz
+	test? ( http://downloads.haskell.org/~ghc/${PV/_/-}/${GHC_P}-testsuite.tar.xz )
+)"
+S="${WORKDIR}"/${GHC_P}
+
+[[ -n $arch_binaries ]] && SRC_URI+=" !ghcbootstrap? ( $arch_binaries )"
+
+BUMP_LIBRARIES=(
+	# "hackage-name          hackage-version"
+)
+
+LICENSE="BSD"
+SLOT="0/${PV}"
+KEYWORDS=""
+IUSE="doc elfutils ghcbootstrap ghcmakebinary +gmp numa profile test"
+IUSE+=" binary"
+
+RDEPEND="
+	>=dev-lang/perl-5.6.1
+	dev-libs/gmp:0=
+	sys-libs/ncurses:0=[unicode]
+	elfutils? ( dev-libs/elfutils )
+	!ghcmakebinary? ( virtual/libffi:= )
+	numa? ( sys-process/numactl )
+"
+
+# This set of dependencies is needed to run
+# prebuilt ghc. We specifically avoid ncurses
+# dependency with:
+#    utils/ghc-pkg_HC_OPTS += -DBOOTSTRAPPING
+PREBUILT_BINARY_DEPENDS="
+	!prefix? ( elibc_glibc? ( >=sys-libs/glibc-2.17 ) )
+"
+# This set of dependencies is needed to install
+# ghc[binary] in system. terminfo package is linked
+# against ncurses.
+PREBUILT_BINARY_RDEPENDS="${PREBUILT_BINARY_DEPENDS}
+	sys-libs/ncurses:0/6
+"
+
+RDEPEND+="binary? ( ${PREBUILT_BINARY_RDEPENDS} )"
+
+DEPEND="${RDEPEND}
+	doc? ( app-text/docbook-xml-dtd:4.2
+		app-text/docbook-xml-dtd:4.5
+		app-text/docbook-xsl-stylesheets
+		dev-python/sphinx
+		>=dev-libs/libxslt-1.1.2 )
+	!ghcbootstrap? ( ${PREBUILT_BINARY_DEPENDS} )"
+
+REQUIRED_USE="?? ( ghcbootstrap binary )"
+
+# haskell libraries built with cabal in configure mode, #515354
+QA_CONFIGURE_OPTIONS+=" --with-compiler --with-gcc"
+
+is_crosscompile() {
+	[[ ${CHOST} != ${CTARGET} ]]
+}
+
+is_native() {
+	[[ ${CHOST} == ${CBUILD} ]] && [[ ${CHOST} == ${CTARGET} ]]
+}
+
+if ! is_crosscompile; then
+	PDEPEND="!ghcbootstrap? ( >=app-admin/haskell-updater-1.2 )"
+fi
+
+# returns tool prefix for crosscompiler.
+# Example:
+#  CTARGET=armv7a-unknown-linux-gnueabi
+#  CHOST=x86_64-pc-linux-gnu
+#    "armv7a-unknown-linux-gnueabi-"
+#  CTARGET=${CHOST}
+#    ""
+# Used in tools and library prefix:
+#    "${ED}"/usr/bin/$(cross)haddock
+#    "${ED}/usr/$(get_libdir)/$(cross)${GHC_P}/package.conf.d"
+
+cross() {
+	if is_crosscompile; then
+		echo "${CTARGET}-"
+	else
+		echo ""
+	fi
+}
+
+append-ghc-cflags() {
+	local persistent compile assemble link
+	local flag ghcflag
+
+	for flag in $*; do
+		case ${flag} in
+			persistent)	persistent="yes";;
+			compile)	compile="yes";;
+			assemble)	assemble="yes";;
+			link)		link="yes";;
+			*)
+				[[ ${compile}  ]] && ghcflag="-optc${flag}"  CFLAGS+=" ${flag}" && GHC_FLAGS+=" ${ghcflag}" &&
+					[[ ${persistent} ]] && GHC_PERSISTENT_FLAGS+=" ${ghcflag}"
+				[[ ${assemble} ]] && ghcflag="-opta${flag}"  CFLAGS+=" ${flag}" && GHC_FLAGS+=" ${ghcflag}" &&
+					[[ ${persistent} ]] && GHC_PERSISTENT_FLAGS+=" ${ghcflag}"
+				[[ ${link}     ]] && ghcflag="-optl${flag}" LDFLAGS+=" ${flag}" && GHC_FLAGS+=" ${ghcflag}" &&
+					[[ ${persistent} ]] && GHC_PERSISTENT_FLAGS+=" ${ghcflag}"
+				;;
+		esac
+	done
+}
+
+# $1 - lib name (under libraries/)
+# $2 - lib version
+# example: bump_lib "transformers" "0.4.2.0"
+bump_lib() {
+	local pn=$1 pv=$2
+	local p=${pn}-${pv}
+	local f
+
+	einfo "Bumping ${pn} up to ${pv}"
+
+	for f in ghc.mk GNUmakefile; do
+		mv libraries/"${pn}"/$f "${WORKDIR}"/"${p}"/$f || die
+	done
+	mv libraries/"${pn}" "${WORKDIR}"/"${pn}".old || die
+	mv "${WORKDIR}"/"${p}" libraries/"${pn}" || die
+}
+
+update_SRC_URI() {
+	local p pn pv
+	for p in "${BUMP_LIBRARIES[@]}"; do
+		set -- $p
+		pn=$1 pv=$2
+
+		SRC_URI+=" mirror://hackage/package/${pn}/${pn}-${pv}.tar.gz"
+	done
+}
+
+update_SRC_URI
+
+bump_libs() {
+	local p pn pv
+	for p in "${BUMP_LIBRARIES[@]}"; do
+		set -- $p
+		pn=$1 pv=$2
+
+		bump_lib "${pn}" "${pv}"
+	done
+}
+
+ghc_setup_cflags() {
+	# TODO: plumb CFLAGS and BUILD_CFLAGS to respective CONF_CC_OPTS_STAGE<N>
+	if ! is_native; then
+		export CFLAGS=${GHC_CFLAGS-"-O2 -pipe"}
+		export LDFLAGS=${GHC_LDFLAGS-"-Wl,-O1"}
+		einfo "Crosscompiling mode:"
+		einfo "   CHOST:   ${CHOST}"
+		einfo "   CTARGET: ${CTARGET}"
+		einfo "   CFLAGS:  ${CFLAGS}"
+		einfo "   LDFLAGS: ${LDFLAGS}"
+		einfo "   prefix: $(cross)"
+		return
+	fi
+	# 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
+
+	# Cmm can't parse line numbers #482086
+	replace-flags -ggdb[3-9] -ggdb2
+
+	GHC_FLAGS=""
+	GHC_PERSISTENT_FLAGS=""
+	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};;
+
+			# Sometimes it's handy to see backtrace of RTS
+			# to get an idea what happens there
+			-g*) append-ghc-cflags compile ${flag};;
+
+			# Ignore all other flags, including all -f* flags
+		esac
+	done
+
+	for flag in ${LDFLAGS}; do
+		append-ghc-cflags link ${flag}
+	done
+
+	# GHC uses ${CBUILD}-gcc, ${CHOST}-gcc and ${CTARGET}-gcc at a single build.
+	# Skip any gentoo-specific tweaks for cross-case to avoid passing unsupported
+	# options to gcc.
+	if is_native; then
+		# hardened-gcc needs to be disabled, because our prebuilt binaries/libraries
+		# are not built with fPIC, bug #606666
+		gcc-specs-pie && append-ghc-cflags persistent compile link -nopie
+		tc-is-gcc && ver_test $(gcc-version) -ge 6.3 && if ! use ghcbootstrap; then
+			# gcc-6.3 has support for -no-pie upstream, but spelling differs from
+			# gentoo-specific '-nopie'. We enable it in non-bootstrap to allow
+			# hardened users try '-pie' in USE=ghcbootstrap mode.
+			append-ghc-cflags compile link -no-pie
+		fi
+
+		# prevent from failing to build unregisterised ghc:
+		# http://www.mail-archive.com/debian-bugs-dist@lists.debian.org/msg171602.html
+		use ppc64 && append-ghc-cflags persistent compile -mminimal-toc
+	fi
+}
+
+# substitutes string $1 to $2 in files $3 $4 ...
+relocate_path() {
+	local from=$1
+	local   to=$2
+	shift 2
+	local file=
+	for file in "$@"
+	do
+		sed -i -e "s|$from|$to|g" \
+			"$file" || die "path relocation failed for '$file'"
+	done
+}
+
+# changes hardcoded ghc paths and updates package index
+# $1 - new absolute root path
+relocate_ghc() {
+	local to=$1 ghc_v=${BIN_PV}
+
+	# libdir for prebuilt binary and for current system may mismatch
+	# It does for prefix installation for example: bug #476998
+	local bin_ghc_prefix=${WORKDIR}/usr
+	local bin_libpath=$(echo "${bin_ghc_prefix}"/lib*)
+	local bin_libdir=${bin_libpath#${bin_ghc_prefix}/}
+
+	# backup original script to use it later after relocation
+	local gp_back="${T}/ghc-pkg-${ghc_v}-orig"
+	cp "${WORKDIR}/usr/bin/ghc-pkg-${ghc_v}" "$gp_back" || die "unable to backup ghc-pkg wrapper"
+
+	if [[ ${bin_libdir} != $(get_libdir) ]]; then
+		einfo "Relocating '${bin_libdir}' to '$(get_libdir)' (bug #476998)"
+		# moving the dir itself is not strictly needed
+		# but then USE=binary would result in installing
+		# in '${bin_libdir}'
+		mv "${bin_ghc_prefix}/${bin_libdir}" "${bin_ghc_prefix}/$(get_libdir)" || die
+
+		relocate_path "/usr/${bin_libdir}" "/usr/$(get_libdir)" \
+			"${WORKDIR}/usr/bin/ghc-${ghc_v}" \
+			"${WORKDIR}/usr/bin/ghci-${ghc_v}" \
+			"${WORKDIR}/usr/bin/ghc-pkg-${ghc_v}" \
+			"${WORKDIR}/usr/bin/hsc2hs" \
+			"${WORKDIR}/usr/bin/runghc-${ghc_v}" \
+			"$gp_back" \
+			"${WORKDIR}/usr/$(get_libdir)/${PN}-${ghc_v}/package.conf.d/"*
+	fi
+
+	# Relocate from /usr to ${EPREFIX}/usr
+	relocate_path "/usr" "${to}/usr" \
+		"${WORKDIR}/usr/bin/ghc-${ghc_v}" \
+		"${WORKDIR}/usr/bin/ghci-${ghc_v}" \
+		"${WORKDIR}/usr/bin/ghc-pkg-${ghc_v}" \
+		"${WORKDIR}/usr/bin/haddock-ghc-${ghc_v}" \
+		"${WORKDIR}/usr/bin/hp2ps" \
+		"${WORKDIR}/usr/bin/hpc" \
+		"${WORKDIR}/usr/bin/hsc2hs" \
+		"${WORKDIR}/usr/bin/runghc-${ghc_v}" \
+		"${WORKDIR}/usr/$(get_libdir)/${PN}-${ghc_v}/package.conf.d/"*
+
+	# this one we will use to regenerate cache
+	# so it should point to current tree location
+	relocate_path "/usr" "${WORKDIR}/usr" "$gp_back"
+
+	if use prefix; then
+		hprefixify "${bin_libpath}"/${PN}*/settings
+	fi
+
+	# regenerate the binary package cache
+	"$gp_back" recache || die "failed to update cache after relocation"
+	rm "$gp_back"
+}
+
+ghc-check-reqs() {
+	# These are pessimistic values (slightly bigger than worst-case)
+	# Worst case is UNREG USE=profile ia64. See bug #611866 for some
+	# numbers on various arches.
+	CHECKREQS_DISK_BUILD=8G
+	CHECKREQS_DISK_USR=2G
+	# USE=binary roughly takes
+	use binary && CHECKREQS_DISK_BUILD=4G
+
+	"$@"
+}
+
+pkg_pretend() {
+	ghc-check-reqs check-reqs_pkg_pretend
+}
+
+pkg_setup() {
+	ghc-check-reqs check-reqs_pkg_setup
+
+	# quiet portage about prebuilt binaries
+	use binary && QA_PREBUILT="*"
+
+	[[ ${MERGE_TYPE} == binary ]] && return
+
+	if use ghcbootstrap; then
+		ewarn "You requested ghc bootstrapping, this is usually only used"
+		ewarn "by Gentoo developers to make binary .tbz2 packages."
+
+		[[ -z $(type -P ghc) ]] && \
+			die "Could not find a ghc to bootstrap with."
+	else
+		if ! yet_binary; then
+			eerror "Please try emerging with USE=ghcbootstrap and report build"
+			eerror "sucess or failure to the haskell team (haskell@gentoo.org)"
+			die "No binary available for '${ARCH}' arch yet, USE=ghcbootstrap"
+		fi
+	fi
+}
+
+src_unpack() {
+	# Create the ${S} dir if we're using the binary version
+	use binary && mkdir "${S}"
+
+	# the Solaris and Darwin binaries from ghc (maeder) need to be
+	# unpacked separately, so prevent them from being unpacked
+	local ONLYA=${A}
+	case ${CHOST} in
+		*-darwin* | *-solaris*)  ONLYA=${GHC_P}-src.tar.xz  ;;
+	esac
+	unpack ${ONLYA}
+}
+
+src_prepare() {
+	ghc_setup_cflags
+
+	if ! use ghcbootstrap && [[ ${CHOST} != *-darwin* && ${CHOST} != *-solaris* ]]; then
+		# Modify the wrapper script from the binary tarball to use GHC_PERSISTENT_FLAGS.
+		# See bug #313635.
+		sed -i -e "s|\"\$topdir\"|\"\$topdir\" ${GHC_PERSISTENT_FLAGS}|" \
+			"${WORKDIR}/usr/bin/ghc-${BIN_PV}"
+
+		# allow hardened users use vanilla binary to bootstrap ghc
+		# ghci uses mmap with rwx protection at it implements dynamic
+		# linking on it's own (bug #299709)
+		pax-mark -m "${WORKDIR}/usr/$(get_libdir)/${PN}-${BIN_PV}/bin/ghc"
+	fi
+
+	if use binary; then
+		if use prefix; then
+			relocate_ghc "${EPREFIX}"
+		fi
+
+		# Move unpacked files to the expected place
+		mv "${WORKDIR}/usr" "${S}"
+		eapply_user
+	else
+		if ! use ghcbootstrap; then
+			case ${CHOST} in
+				*-darwin* | *-solaris*)
+				# UPDATE ME for ghc-7
+				mkdir "${WORKDIR}"/ghc-bin-installer || die
+				pushd "${WORKDIR}"/ghc-bin-installer > /dev/null || die
+				use sparc-solaris && unpack ghc-6.10.4-sparc-sun-solaris2.tar.bz2
+				use x86-solaris && unpack ghc-7.0.3-i386-unknown-solaris2.tar.bz2
+				use x86-macos && unpack ghc-7.4.1-i386-apple-darwin.tar.bz2
+				use x64-macos && unpack ghc-7.4.1-x86_64-apple-darwin.tar.bz2
+				popd > /dev/null
+
+				pushd "${WORKDIR}"/ghc-bin-installer/ghc-[67].?*.? > /dev/null || die
+				# fix the binaries so they run, on Solaris we need an
+				# LD_LIBRARY_PATH which has our prefix libdirs, on
+				# Darwin we need to replace the frameworks with our libs
+				# from the prefix fix before installation, because some
+				# of the tools are actually used during configure/make
+				if [[ ${CHOST} == *-solaris* ]] ; then
+					export LD_LIBRARY_PATH="${EPREFIX}/$(get_libdir):${EPREFIX}/usr/$(get_libdir):${LD_LIBRARY_PATH}"
+				elif [[ ${CHOST} == *-darwin* ]] ; then
+					local readline_framework=GNUreadline.framework/GNUreadline
+					local gmp_framework=/opt/local/lib/libgmp.10.dylib
+					local ncurses_file=/opt/local/lib/libncurses.5.dylib
+					for binary in $(scanmacho -BRE MH_EXECUTE -F '%F' .) ; do
+						install_name_tool -change \
+							${readline_framework} \
+							"${EPREFIX}"/lib/libreadline.dylib \
+							${binary} || die
+						install_name_tool -change \
+							${gmp_framework} \
+							"${EPREFIX}"/usr/lib/libgmp.dylib \
+							${binary} || die
+						install_name_tool -change \
+							${ncurses_file} \
+							"${EPREFIX}"/usr/lib/libncurses.dylib \
+							${binary} || die
+					done
+					# we don't do frameworks!
+					sed -i \
+						-e 's/\(frameworks = \)\["GMP"\]/\1[]/g' \
+						-e 's/\(extraLibraries = \)\["m"\]/\1["m","gmp"]/g' \
+						rts/package.conf.in || die
+				fi
+
+				# it is autoconf, but we really don't want to give it too
+				# many arguments, in fact we do the make in-place anyway
+				./configure --prefix="${WORKDIR}"/usr || die
+				make install || die
+				popd > /dev/null
+				;;
+				*)
+				relocate_ghc "${WORKDIR}"
+				;;
+			esac
+		fi
+
+		sed -i -e "s|\"\$topdir\"|\"\$topdir\" ${GHC_PERSISTENT_FLAGS}|" \
+			"${S}/ghc/ghc.wrapper"
+
+		cd "${S}" # otherwise eapply will break
+
+		eapply "${FILESDIR}"/${PN}-7.0.4-CHOST-prefix.patch
+		eapply "${FILESDIR}"/${PN}-8.2.1-darwin.patch
+		eapply "${FILESDIR}"/${PN}-7.8.3-prim-lm.patch
+		eapply "${FILESDIR}"/${PN}-8.0.2-no-relax-everywhere.patch
+		eapply "${FILESDIR}"/${PN}-8.4.2-allow-cross-bootstrap.patch
+		eapply "${FILESDIR}"/${PN}-8.6.5-numa.patch
+		eapply "${FILESDIR}"/${PN}-8.8.1-no-alex.patch
+		eapply "${FILESDIR}"/${PN}-8.8.1-revert-CPP.patch
+
+		# a bunch of crosscompiler patches
+		# needs newer version:
+		#eapply "${FILESDIR}"/${PN}-8.2.1_rc1-hp2ps-cross.patch
+
+		# mingw32 target
+		pushd "${S}/libraries/Win32"
+			eapply "${FILESDIR}"/${PN}-8.2.1_rc1-win32-cross-2-hack.patch # bad workaround
+		popd
+
+		bump_libs
+
+		eapply_user
+		# as we have changed the build system
+		eautoreconf
+	fi
+}
+
+src_configure() {
+	if ! use binary; then
+		# initialize build.mk
+		echo '# Gentoo changes' > mk/build.mk
+
+		# Put docs into the right place, ie /usr/share/doc/ghc-${GHC_PV}
+		echo "docdir = ${EPREFIX}/usr/share/doc/$(cross)${P}" >> mk/build.mk
+		echo "htmldir = ${EPREFIX}/usr/share/doc/$(cross)${P}" >> mk/build.mk
+
+		# We also need to use the GHC_FLAGS flags when building ghc itself
+		echo "SRC_HC_OPTS+=${HCFLAGS} ${GHC_FLAGS}" >> mk/build.mk
+		echo "SRC_CC_OPTS+=${CFLAGS}" >> mk/build.mk
+		echo "SRC_LD_OPTS+=${LDFLAGS}" >> mk/build.mk
+		# Speed up initial Cabal bootstrap
+		echo "utils/ghc-cabal_dist_EXTRA_HC_OPTS+=$(ghc-make-args)" >> mk/build.mk
+
+		# We can't depend on haddock except when bootstrapping when we
+		# must build docs and include them into the binary .tbz2 package
+		# app-text/dblatex is not in portage, can not build PDF or PS
+		echo "BUILD_SPHINX_PDF  = NO"  >> mk/build.mk
+		echo "BUILD_SPHINX_HTML = $(usex doc YES NO)" >> mk/build.mk
+		echo "BUILD_MAN = $(usex doc YES NO)" >> mk/build.mk
+
+		# this controls presence on 'xhtml' and 'haddock' in final install
+		echo "HADDOCK_DOCS       = YES" >> mk/build.mk
+
+		# not used outside of ghc's test
+		if [[ -n ${GHC_BUILD_DPH} ]]; then
+				echo "BUILD_DPH = YES" >> mk/build.mk
+			else
+				echo "BUILD_DPH = NO" >> mk/build.mk
+		fi
+
+		# Any non-native build has to skip as it needs
+		# target haddock binary to be runnabine.
+		if ! is_native; then
+			# disable docs generation as it requires running stage2
+			echo "HADDOCK_DOCS=NO" >> mk/build.mk
+			echo "BUILD_SPHINX_HTML=NO" >> mk/build.mk
+			echo "BUILD_SPHINX_PDF=NO" >> mk/build.mk
+		fi
+
+		if is_crosscompile; then
+			# Install ghc-stage1 crosscompiler instead of
+			# ghc-stage2 cross-built compiler.
+			echo "Stage1Only=YES" >> mk/build.mk
+		fi
+
+		# allows overriding build flavours for libraries:
+		# v   - vanilla (static libs)
+		# p   - profiled
+		# dyn - shared libraries
+		# example: GHC_LIBRARY_WAYS="v dyn"
+		if [[ -n ${GHC_LIBRARY_WAYS} ]]; then
+			echo "GhcLibWays=${GHC_LIBRARY_WAYS}" >> mk/build.mk
+		fi
+		echo "BUILD_PROF_LIBS = $(usex profile YES NO)" >> mk/build.mk
+
+		# Get ghc from the unpacked binary .tbz2
+		# except when bootstrapping we just pick ghc up off the path
+		if ! use ghcbootstrap; then
+			export PATH="${WORKDIR}/usr/bin:${PATH}"
+		fi
+
+		echo "INTEGER_LIBRARY = $(usex gmp integer-gmp integer-simple)" >> mk/build.mk
+
+		# don't strip anything. Very useful when stage2 SIGSEGVs on you
+		echo "STRIP_CMD = :" >> mk/build.mk
+
+		local econf_args=()
+
+		# GHC embeds toolchain it was built by and uses it later.
+		# Don't allow things like ccache or versioned binary slip.
+		# We use stable thing across gcc upgrades.
+		# User can use EXTRA_ECONF=CC=... to override this default.
+		econf_args+=(
+			AR=${CTARGET}-ar
+			CC=${CTARGET}-gcc
+			# these should be inferred by GHC but ghc defaults
+			# to using bundled tools on windows.
+			Windres=${CTARGET}-windres
+			DllWrap=${CTARGET}-dllwrap
+			# we set the linker explicitly below
+			--disable-ld-override
+		)
+		case ${CTARGET} in
+			arm*)
+				# ld.bfd-2.28 does not work for ghc. Force ld.gold
+				# instead. This should be removed once gentoo gets
+				# a fix for R_ARM_COPY bug: https://sourceware.org/PR16177
+				econf_args+=(LD=${CTARGET}-ld.gold)
+			;;
+			sparc*)
+				# ld.gold-2.28 does not work for ghc. Force ld.bfd
+				# instead. This should be removed once gentoo gets
+				# a fix for missing --no-relax support bug:
+				# https://sourceware.org/ml/binutils/2017-07/msg00183.html
+				econf_args+=(LD=${CTARGET}-ld.bfd)
+			;;
+			*)
+				econf_args+=(LD=${CTARGET}-ld)
+		esac
+
+		if [[ ${CBUILD} != ${CHOST} ]]; then
+			# GHC bug: ghc claims not to support cross-building.
+			# It does, but does not distinct --host= value
+			# for stage1 and stage2 compiler.
+			econf_args+=(--host=${CBUILD})
+		fi
+
+		if use ghcmakebinary; then
+			# When building booting libary we are trying to
+			# bundle or restrict most of external depends
+			# with unstable ABI:
+			#  - embed libffi (default GHC behaviour)
+			#  - disable ncurses support for ghci (via haskeline)
+			#    https://bugs.gentoo.org/557478
+			#  - disable ncurses support for ghc-pkg
+			echo "libraries/haskeline_CONFIGURE_OPTS += --flag=-terminfo" >> mk/build.mk
+			echo "utils/ghc-pkg_HC_OPTS += -DBOOTSTRAPPING" >> mk/build.mk
+		elif is_native; then
+			# using ${GTARGET}'s libffi is not supported yet:
+			# GHC embeds full path for ffi includes without /usr/${CTARGET} account.
+			econf_args+=(--with-system-libffi)
+			econf_args+=(--with-ffi-includes=$(pkg-config libffi --cflags-only-I | sed -e 's@^-I@@'))
+		fi
+
+		einfo "Final mk/build.mk:"
+		cat mk/build.mk || die
+
+		econf ${econf_args[@]} \
+			--enable-bootstrap-with-devel-snapshot \
+			$(use elfutils && echo --enable-dwarf-unwind) \
+			$(use_enable numa)
+
+		if [[ ${PV} == *9999* ]]; then
+			GHC_PV="$(grep 'S\[\"PACKAGE_VERSION\"\]' config.status | sed -e 's@^.*=\"\(.*\)\"@\1@')"
+			GHC_P=${PN}-${GHC_PV}
+		fi
+	fi # ! use binary
+}
+
+src_compile() {
+	if ! use binary; then
+		# Stage1Only crosscompiler does not build stage2
+		if ! is_crosscompile; then
+			# 1. build/pax-mark compiler binary first
+			emake ghc/stage2/build/tmp/ghc-stage2
+			# 2. pax-mark (bug #516430)
+			pax-mark -m ghc/stage2/build/tmp/ghc-stage2
+			# 2. build/pax-mark haddock using ghc-stage2
+			if is_native; then
+				# non-native build does not build haddock
+				# due to HADDOCK_DOCS=NO, but it could.
+				emake utils/haddock/dist/build/tmp/haddock
+				pax-mark -m utils/haddock/dist/build/tmp/haddock
+			fi
+		fi
+		# 3. and then all the rest
+		emake all
+	fi # ! use binary
+}
+
+src_test() {
+	# TODO: deal with:
+	#    - sandbox (pollutes environment)
+	#    - extra packages (to extend testsuite coverage)
+	# bits are taken from 'validate'
+	local make_test_target='test' # can be fulltest
+	# not 'emake' as testsuite uses '$MAKE' without jobserver available
+	make $make_test_target stage=2 THREADS=$(makeopts_jobs)
+}
+
+src_install() {
+	if use binary; then
+		use prefix && mkdir -p "${ED}"
+		mv "${S}/usr" "${ED}"
+	else
+		[[ -f VERSION ]] || emake VERSION
+
+		# -j1 due to a rare race in install script:
+		#    make --no-print-directory -f ghc.mk phase=final install
+		#    /usr/lib/portage/python3.4/ebuild-helpers/xattr/install -c -m 755 \
+		#        -d "/tmp/portage-tmpdir/portage/cross-armv7a-unknown-linux-gnueabi/ghc-9999/image/usr/lib64/armv7a-unknown-linux-gnueabi-ghc-8.3.20170404/include"
+		#    /usr/lib/portage/python3.4/ebuild-helpers/xattr/install -c -m 644  utils/hsc2hs/template-hsc.h \
+		#           "/tmp/portage-tmpdir/portage/cross-armv7a-unknown-linux-gnueabi/ghc-9999/image/usr/lib64/armv7a-unknown-linux-gnueabi-ghc-8.3.20170404"
+		#    /usr/bin/install: cannot create regular file \
+		#           '/tmp/portage-tmpdir/portage/cross-armv7a-unknown-linux-gnueabi/ghc-9999/image/usr/lib64/armv7a-unknown-linux-gnueabi-ghc-8.3.20170404': No such file or directory
+		emake -j1 install DESTDIR="${D}"
+
+		# Skip for cross-targets as they all share target location:
+		# /usr/share/doc/ghc-9999/
+		if ! is_crosscompile; then
+			dodoc "distrib/README" "ANNOUNCE" "LICENSE" "VERSION"
+		fi
+
+		# rename ghc-shipped files to avoid collision
+		# of external packages. Motivating example:
+		#  user had installed:
+		#      dev-lang/ghc-7.8.4-r0 (with transformers-0.3.0.0)
+		#      dev-haskell/transformers-0.4.2.0
+		#  then user tried to update to
+		#      dev-lang/ghc-7.8.4-r1 (with transformers-0.4.2.0)
+		#  this will lead to single .conf file collision.
+		local shipped_conf renamed_conf
+		local package_confdir="${ED}/usr/$(get_libdir)/$(cross)${GHC_P}/package.conf.d"
+		for shipped_conf in "${package_confdir}"/*.conf; do
+			# rename 'pkg-ver-id.conf' to 'pkg-ver-id-gentoo-${PF}.conf'
+			renamed_conf=${shipped_conf%.conf}-gentoo-${PF}.conf
+			mv "${shipped_conf}" "${renamed_conf}" || die
+		done
+
+		# remove link, but leave 'haddock-${GHC_P}'
+		rm -f "${ED}"/usr/bin/$(cross)haddock
+
+		if ! is_crosscompile; then
+			newbashcomp "${FILESDIR}"/ghc-bash-completion ghc-pkg
+			newbashcomp utils/completion/ghc.bash         ghc
+		fi
+	fi
+
+	# path to the package.cache
+	local package_confdir="${ED}/usr/$(get_libdir)/$(cross)${GHC_P}/package.conf.d"
+	PKGCACHE="${package_confdir}"/package.cache
+	# copy the package.conf.d, including timestamp, save it so we can help
+	# users that have a broken package.conf.d
+	cp -pR "${package_confdir}"{,.initial} || die "failed to backup intial package.conf.d"
+
+	# copy the package.conf, including timestamp, save it so we later can put it
+	# back before uninstalling, or when upgrading.
+	cp -p "${PKGCACHE}"{,.shipped} \
+		|| die "failed to copy package.conf.d/package.cache"
+
+	if is_crosscompile; then
+		# When we build a cross-compiler the layout is the following:
+		#     usr/lib/${CTARGET}-ghc-${VER}/ contains target libraries
+		# but
+		#     usr/lib/${CTARGET}-ghc-${VER}/bin/ directory
+		# containst host binaries (modulo bugs).
+
+		# Portage's stripping mechanism does not skip stripping
+		# foreign binaries. This frequently causes binaries to be
+		# broken.
+		#
+		# Thus below we disable stripping of target libraries and allow
+		# stripping hosts executables.
+		dostrip -x "/usr/$(get_libdir)/$(cross)${GHC_P}"
+		dostrip    "/usr/$(get_libdir)/$(cross)${GHC_P}/bin"
+	fi
+}
+
+pkg_preinst() {
+	# have we got an earlier version of ghc installed?
+	if has_version "<${CATEGORY}/${PF}"; then
+		haskell_updater_warn="1"
+	fi
+}
+
+pkg_postinst() {
+	ghc-reregister
+
+	# path to the package.cache
+	PKGCACHE="${EROOT}/usr/$(get_libdir)/$(cross)${GHC_P}/package.conf.d/package.cache"
+
+	# give the cache a new timestamp, it must be as recent as
+	# the package.conf.d directory.
+	touch "${PKGCACHE}"
+
+	if [[ "${haskell_updater_warn}" == "1" ]]; then
+		ewarn
+		ewarn "\e[1;31m************************************************************************\e[0m"
+		ewarn
+		ewarn "You have just upgraded from an older version of GHC."
+		ewarn "You may have to run"
+		ewarn "      'haskell-updater'"
+		ewarn "to rebuild all ghc-based Haskell libraries."
+		ewarn
+		ewarn "\e[1;31m************************************************************************\e[0m"
+		ewarn
+	fi
+}
+
+pkg_prerm() {
+	PKGCACHE="${EROOT}/usr/$(get_libdir)/$(cross)${GHC_P}/package.conf.d/package.cache"
+	rm -rf "${PKGCACHE}"
+
+	cp -p "${PKGCACHE}"{.shipped,}
+}
+
+pkg_postrm() {
+	ghc-package_pkg_postrm
+}
--- a/dev-lang/ghc/metadata.xml
+++ b/dev-lang/ghc/metadata.xml
@@ -7,7 +7,10 @@
 	</maintainer>
 	<use>
 		<flag name="binary">Install the binary version directly, rather than using it to build the source version.</flag>
+		<flag name="elfutils">Enable DWARF-based baclktraces using <pkg>dev-libs/elfutils</pkg>.</flag>
 		<flag name="ghcbootstrap">Internal: Bootstrap GHC from an existing GHC installation.</flag>
 		<flag name="ghcmakebinary">Internal: Build binary friendly for redistribution.</flag>
+		<flag name="gmp">use <pkg>dev-libs/gmp</pkg> for integer operations (works faster, but an external depend).</flag>
+		<flag name="numa">Enable NUMA thread balancing policy using <pkg>sys-process/numactl</pkg>.</flag>
 	</use>
 </pkgmetadata>