[gentoo-dev] [PATCH 3/6] usr-ldscript.eclass: copy gen_usr_ldscript from toolchain-funcs.eclass

[Mike Gilbert]

This intentionally redefines the same function to ease migration. Once
all ebuilds have been converted, the definition in toolchain-funcs can
be removed.

Signed-off-by: Mike Gilbert <floppym@g.o>
---
 eclass/usr-ldscript.eclass | 156 +++++++++++++++++++++++++++++++++++++
 1 file changed, 156 insertions(+)
 create mode 100644 eclass/usr-ldscript.eclass

diff --git a/eclass/usr-ldscript.eclass b/eclass/usr-ldscript.eclass
new file mode 100644
index 000000000000..c1abbb49f4ba
--- /dev/null
+++ b/eclass/usr-ldscript.eclass
@@ -0,0 +1,156 @@
+# Copyright 2019 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+# @ECLASS: usr-ldscript.eclass
+# @MAINTAINER:
+# Toolchain Ninjas <toolchain@g.o>
+# @AUTHOR:
+# Mike Gilbert <floppym@g.o>
+# @BLURB: Defines the gen_usr_ldscript function.
+
+if [[ -z ${_USR_LDSCRIPT_ECLASS} ]]; then
+_USR_LDSCRIPT_ECLASS=1
+
+inherit multilib toolchain-funcs
+
+# @FUNCTION: gen_usr_ldscript
+# @USAGE: [-a] <list of libs to create linker scripts for>
+# @DESCRIPTION:
+# This function generate linker scripts in /usr/lib for dynamic
+# libs in /lib.  This is to fix linking problems when you have
+# the .so in /lib, and the .a in /usr/lib.  What happens is that
+# in some cases when linking dynamic, the .a in /usr/lib is used
+# instead of the .so in /lib due to gcc/libtool tweaking ld's
+# library search path.  This causes many builds to fail.
+# See bug #4411 for more info.
+#
+# Note that you should in general use the unversioned name of
+# the library (libfoo.so), as ldconfig should usually update it
+# correctly to point to the latest version of the library present.
+gen_usr_ldscript() {
+	local lib libdir=$(get_libdir) output_format="" auto=false suffix=$(get_libname)
+	[[ -z ${ED+set} ]] && local ED=${D%/}${EPREFIX}/
+
+	tc-is-static-only && return
+
+	# We only care about stuffing / for the native ABI. #479448
+	if [[ $(type -t multilib_is_native_abi) == "function" ]] ; then
+		multilib_is_native_abi || return 0
+	fi
+
+	# Eventually we'd like to get rid of this func completely #417451
+	case ${CTARGET:-${CHOST}} in
+	*-darwin*) ;;
+	*-android*) return 0 ;;
+	*linux*|*-freebsd*|*-openbsd*|*-netbsd*)
+		use prefix && return 0 ;;
+	*) return 0 ;;
+	esac
+
+	# Just make sure it exists
+	dodir /usr/${libdir}
+
+	if [[ $1 == "-a" ]] ; then
+		auto=true
+		shift
+		dodir /${libdir}
+	fi
+
+	# OUTPUT_FORMAT gives hints to the linker as to what binary format
+	# is referenced ... makes multilib saner
+	local flags=( ${CFLAGS} ${LDFLAGS} -Wl,--verbose )
+	if $(tc-getLD) --version | grep -q 'GNU gold' ; then
+		# If they're using gold, manually invoke the old bfd. #487696
+		local d="${T}/bfd-linker"
+		mkdir -p "${d}"
+		ln -sf $(which ${CHOST}-ld.bfd) "${d}"/ld
+		flags+=( -B"${d}" )
+	fi
+	output_format=$($(tc-getCC) "${flags[@]}" 2>&1 | sed -n 's/^OUTPUT_FORMAT("\([^"]*\)",.*/\1/p')
+	[[ -n ${output_format} ]] && output_format="OUTPUT_FORMAT ( ${output_format} )"
+
+	for lib in "$@" ; do
+		local tlib
+		if ${auto} ; then
+			lib="lib${lib}${suffix}"
+		else
+			# Ensure /lib/${lib} exists to avoid dangling scripts/symlinks.
+			# This especially is for AIX where $(get_libname) can return ".a",
+			# so /lib/${lib} might be moved to /usr/lib/${lib} (by accident).
+			[[ -r ${ED}/${libdir}/${lib} ]] || continue
+			#TODO: better die here?
+		fi
+
+		case ${CTARGET:-${CHOST}} in
+		*-darwin*)
+			if ${auto} ; then
+				tlib=$(scanmacho -qF'%S#F' "${ED}"/usr/${libdir}/${lib})
+			else
+				tlib=$(scanmacho -qF'%S#F' "${ED}"/${libdir}/${lib})
+			fi
+			[[ -z ${tlib} ]] && die "unable to read install_name from ${lib}"
+			tlib=${tlib##*/}
+
+			if ${auto} ; then
+				mv "${ED}"/usr/${libdir}/${lib%${suffix}}.*${suffix#.} "${ED}"/${libdir}/ || die
+				# some install_names are funky: they encode a version
+				if [[ ${tlib} != ${lib%${suffix}}.*${suffix#.} ]] ; then
+					mv "${ED}"/usr/${libdir}/${tlib%${suffix}}.*${suffix#.} "${ED}"/${libdir}/ || die
+				fi
+				rm -f "${ED}"/${libdir}/${lib}
+			fi
+
+			# Mach-O files have an id, which is like a soname, it tells how
+			# another object linking against this lib should reference it.
+			# Since we moved the lib from usr/lib into lib this reference is
+			# wrong.  Hence, we update it here.  We don't configure with
+			# libdir=/lib because that messes up libtool files.
+			# Make sure we don't lose the specific version, so just modify the
+			# existing install_name
+			if [[ ! -w "${ED}/${libdir}/${tlib}" ]] ; then
+				chmod u+w "${ED}${libdir}/${tlib}" # needed to write to it
+				local nowrite=yes
+			fi
+			install_name_tool \
+				-id "${EPREFIX}"/${libdir}/${tlib} \
+				"${ED}"/${libdir}/${tlib} || die "install_name_tool failed"
+			[[ -n ${nowrite} ]] && chmod u-w "${ED}${libdir}/${tlib}"
+			# Now as we don't use GNU binutils and our linker doesn't
+			# understand linker scripts, just create a symlink.
+			pushd "${ED}/usr/${libdir}" > /dev/null
+			ln -snf "../../${libdir}/${tlib}" "${lib}"
+			popd > /dev/null
+			;;
+		*)
+			if ${auto} ; then
+				tlib=$(scanelf -qF'%S#F' "${ED}"/usr/${libdir}/${lib})
+				[[ -z ${tlib} ]] && die "unable to read SONAME from ${lib}"
+				mv "${ED}"/usr/${libdir}/${lib}* "${ED}"/${libdir}/ || die
+				# some SONAMEs are funky: they encode a version before the .so
+				if [[ ${tlib} != ${lib}* ]] ; then
+					mv "${ED}"/usr/${libdir}/${tlib}* "${ED}"/${libdir}/ || die
+				fi
+				rm -f "${ED}"/${libdir}/${lib}
+			else
+				tlib=${lib}
+			fi
+			cat > "${ED}/usr/${libdir}/${lib}" <<-END_LDSCRIPT
+			/* GNU ld script
+			   Since Gentoo has critical dynamic libraries in /lib, and the static versions
+			   in /usr/lib, we need to have a "fake" dynamic lib in /usr/lib, otherwise we
+			   run into linking problems.  This "fake" dynamic lib is a linker script that
+			   redirects the linker to the real lib.  And yes, this works in the cross-
+			   compiling scenario as the sysroot-ed linker will prepend the real path.
+
+			   See bug https://bugs.gentoo.org/4411 for more info.
+			 */
+			${output_format}
+			GROUP ( ${EPREFIX}/${libdir}/${tlib} )
+			END_LDSCRIPT
+			;;
+		esac
+		fperms a+x "/usr/${libdir}/${lib}" || die "could not change perms on ${lib}"
+	done
+}
+
+fi # _USR_LDSCRIPT_ECLASS
-- 
2.22.0