added CABAL_EXTRA_CONFIGURE_FLAGS variable, more tweaks

- CABAL_EXTRA_CONFIGURE_FLAGS - variable similar to EXTRA_ECONF for econf.
  It appends given arguments to 'runhaskell Setup configure args' call.
  It's handy when one wants to pass some argument for all haskell packages,
  like 'CABAL_EXTRA_CONFIGURE_FLAGS=--enable-shared' to get shared variants
  for all haskell libraries.

- GHC_BOOTSTRAP_FLAGS - ghc option when building Setup.hs.

- fix CABAL_FEATURES="nocabaldep" (found by Felipe Almeida Lessa)

    Felipe's output for ghc-6.12.3:
    > $ ghc-pkg field Cabal version
    > version: 1.8.0.6
    > version: 1.10.1.0

    My output for ghc-6.12.3:
    > $ ghc-pkg field Cabal version
    >    version: 1.10.1.0
    >    version: 1.8.0.6

    It has unstable order and breaks dev-haskell/cairo setup.

    Now we always pick ghc's Cabal version (as CABAL_FROM_GHC var name says),
    not the most recently installed.

- Setup.hs is linked dynamically where available. Drastically speedups (from
  tens of seconds down to seconds) link time (and the whole package build time).

- src_compile() got a QA warning when passed '--flags=' argument for EAPI,
  where yet src_configure() (catches potential package misconfiguration)

1 files changed, 55 insertions, 23 deletions

diff --git a/eclass/haskell-cabal.eclass b/eclass/haskell-cabal.eclass
index 369deeb0c454..a6776dff01b8 100644
--- a/eclass/haskell-cabal.eclass
+++ b/eclass/haskell-cabal.eclass
@@ -1,6 +1,6 @@
 # Copyright 1999-2011 Gentoo Foundation
 # Distributed under the terms of the GNU General Public License v2
-# $Header: /var/cvsroot/gentoo-x86/eclass/haskell-cabal.eclass,v 1.23 2011/03/13 20:15:14 slyfox Exp $
+# $Header: /var/cvsroot/gentoo-x86/eclass/haskell-cabal.eclass,v 1.24 2011/05/08 15:13:10 slyfox Exp $
 #
 # Original authors: Andres Loeh <kosmikus@gentoo.org>
 #                   Duncan Coutts <dcoutts@gentoo.org>
@@ -46,6 +46,20 @@
 
 inherit ghc-package multilib
 
+# @ECLASS-VARIABLE: CABAL_EXTRA_CONFIGURE_FLAGS
+# @DESCRIPTION:
+# User-specified additional parameters passed to 'setup configure'.
+# example: /etc/make.conf: CABAL_EXTRA_CONFIGURE_FLAGS=--enable-shared
+: ${CABAL_EXTRA_CONFIGURE_FLAGS:=}
+
+# @ECLASS-VARIABLE: GHC_BOOTSTRAP_FLAGS
+# @DESCRIPTION:
+# User-specified additional parameters for ghc when building
+# _only_ 'setup' binary bootstrap.
+# example: /etc/make.conf: GHC_BOOTSTRAP_FLAGS=-dynamic to make
+# linking 'setup' faster.
+: ${GHC_BOOTSTRAP_FLAGS:=}
+
 HASKELL_CABAL_EXPF="pkg_setup src_compile src_test src_install"
 
 case "${EAPI:-0}" in
@@ -125,21 +139,9 @@ cabal-version() {
 			# of this package itself.
 			_CABAL_VERSION_CACHE="${PV}"
 		elif [[ "${CABAL_FROM_GHC}" ]]; then
-			# We can't assume there's a version of Cabal installed by ebuild as
-			# this might be a first time install of GHC (for packages that
-			# use the shipped Cabal like haskell-updater).
-
-			# The user is likely to only have one version of Cabal, provided
-			# by GHC. Note that dev-haskell/cabal can be a dummy package, only
-			# using the version provided by GHC. If the user has another version
-			# of Cabal too (more recent than the one GHC provides through
-			# dev-haskell/cabal, or possibly older if he used an old
-			# Cabal package) the most recent is used (expected to be the last
-			# one in the ghc-pkg output).
-			_CABAL_VERSION_CACHE="$(ghc-pkg field Cabal version | tail -n 1)"
-
-			# Strip out the "version: " prefix
-			_CABAL_VERSION_CACHE="${_CABAL_VERSION_CACHE#"version: "}"
+			local cabal_package=$(echo "$(ghc-libdir)"/Cabal-*)
+			# /path/to/ghc/Cabal-${VER} -> ${VER}
+			_CABAL_VERSION_CACHE="${cabal_package/*Cabal-/}"
 		else
 			# We ask portage, not ghc, so that we only pick up
 			# portage-installed cabal versions.
@@ -171,8 +173,20 @@ cabal-bootstrap() {
 		cabalpackage=Cabal
 	fi
 	einfo "Using cabal-$(cabal-version)."
-	$(ghc-getghc) -package "${cabalpackage}" --make "${setupmodule}" -o setup \
-		|| die "compiling ${setupmodule} failed"
+
+	make_setup() {
+		$(ghc-getghc) -package "${cabalpackage}" --make "${setupmodule}" \
+			${GHC_BOOTSTRAP_FLAGS} \
+			"$@" \
+			-o setup
+	}
+	if $(ghc-supports-shared-libraries); then
+		# some custom build systems might use external libraries,
+		# for which we don't have shared libs, so keep static fallback
+		make_setup -dynamic "$@" || make_setup "$@" || die "compiling ${setupmodule} failed"
+	else
+		make_setup "$@" || die "compiling ${setupmodule} failed"
+	fi
 }
 
 cabal-mksetup() {
@@ -232,6 +246,11 @@ cabal-configure() {
 		cabalconf="${cabalconf} --disable-library-for-ghci"
 	fi
 
+	# currently cabal does not respect CFLAGS and LDFLAGS on it's own (bug #333217)
+	# so translate LDFLAGS to ghc parameters (without filtering)
+	local flag
+	for flag in $LDFLAGS; do cabalconf="${cabalconf} --ghc-option=-optl$flag"; done
+
 	if version_is_at_least "1.4" "$(cabal-version)"; then
 		# disable executable stripping for the executables, as portage will
 		# strip by itself, and pre-stripping gives a QA warning.
@@ -254,6 +273,12 @@ cabal-configure() {
 	# rather than	/usr/share/doc/${PF}/
 	# Because we can only set the datadir, not the docdir.
 
+	# We build shared version of our Cabal where ghc ships it's shared
+	# version of it. We will link ./setup as dynamic binary againt Cabal later.
+	[[ ${CATEGORY}/${PN} == "dev-haskell/cabal" ]] && \
+		$(ghc-supports-shared-libraries) && \
+			cabalconf="${cabalconf} --enable-shared"
+
 	./setup configure \
 		--ghc --prefix="${EPREFIX}"/usr \
 		--with-compiler="$(ghc-getghc)" \
@@ -265,6 +290,7 @@ cabal-configure() {
 		--datasubdir=${P}/ghc-$(ghc-version) \
 		${cabalconf} \
 		${CABAL_CONFIGURE_FLAGS} \
+		${CABAL_EXTRA_CONFIGURE_FLAGS} \
 		"$@" || die "setup configure failed"
 }
 
@@ -365,11 +391,6 @@ haskell-cabal_src_configure() {
 
 		cabal-bootstrap
 
-		ghc_flags=""
-		# currently cabal does not respect CFLAGS and LDFLAGS on it's own (bug #333217)
-		# so translate LDFLAGS to ghc parameters (without filtering)
-		for flag in $LDFLAGS; do ghc_flags="${ghc_flags} --ghc-option=-optl$flag"; done
-
 		cabal-configure $ghc_flags "$@"
 
 		popd > /dev/null
@@ -383,6 +404,17 @@ cabal_src_configure() {
 
 # exported function: cabal-style bootstrap configure and compile
 cabal_src_compile() {
+	# it's a common mistake when one bumps ebuild to EAPI="2" (and upper)
+	# and forgets to separate src_compile() to src_configure()/src_compile().
+	# Such error leads to default src_configure and we lose all passed flags.
+	if ! has "${EAPI:-0}" 0 1; then
+		local passed_flag
+		for passed_flag in "$@"; do
+			[[ ${passed_flag} == --flags=* ]] && \
+				eqawarn "Cabal option '${passed_flag}' has effect only in src_configure()"
+		done
+	fi
+
 	if ! cabal-is-dummy-lib; then
 		has src_configure ${HASKELL_CABAL_EXPF} || haskell-cabal_src_configure "$@"
 		cabal-build