sys-libs/glibc: Strip prefix from ld scripts for better cross-compiling

The toolchain expects to find the libc's files under its own sysroot. This
sysroot is automatically prepended to paths found in ld scripts, such as those
installed with glibc. We configure standalone prefix systems with a sysroot, so
these paths should not be prefixed. However, Gentoo Prefix has traditionally
left them prefixed and stopped the compiler from passing the sysroot to the
linker instead. It is better to strip the prefix and let the sysroot do its job,
as this makes cross-compiling much less awkward.

prefix-guest systems do not have a sysroot applied, as they use the host's libc,
but they would not install glibc anyway.

This change is not needed for musl, as it does not install any ld scripts.

Signed-off-by: James Le Cuirot <chewi@gentoo.org>

4 files changed, 34 insertions, 8 deletions

diff --git a/profiles/features/prefix/standalone/profile.bashrc b/profiles/features/prefix/standalone/profile.bashrc
index fd95e43f7f30..3cdda77b9a88 100644
--- a/profiles/features/prefix/standalone/profile.bashrc
+++ b/profiles/features/prefix/standalone/profile.bashrc
@@ -1,5 +1,5 @@
 # -*- mode: shell-script; -*-
-# Copyright 2018-2021 Gentoo Authors
+# Copyright 2018-2022 Gentoo Authors
 # Distributed under the terms of the GNU General Public License v2
 
 # RAP specific patches pending upstream:
@@ -24,10 +24,6 @@ if [[ ${CATEGORY}/${PN} == sys-devel/gcc && ${EBUILD_PHASE} == configure ]]; the
 
     # use sysroot of toolchain to get correct include and library at compile time
     EXTRA_ECONF="${EXTRA_ECONF} --with-sysroot=${EPREFIX}"
-
-    ebegin "remove --sysroot call on ld for native toolchain"
-    sed -i 's/--sysroot=%R//' gcc/gcc.c*
-    eend $?
 elif [[ ${CATEGORY}/${PN} == sys-devel/clang && ${EBUILD_PHASE} == configure ]]; then
     ebegin "Use ${EPREFIX} as default sysroot"
     sed -i -e "s@DEFAULT_SYSROOT \"\"@DEFAULT_SYSROOT \"${EPREFIX}\"@" "${S}"/CMakeLists.txt
@@ -36,9 +32,6 @@ elif [[ ${CATEGORY}/${PN} == sys-devel/clang && ${EBUILD_PHASE} == configure ]];
     ebegin "Use dynamic linker from ${EPREFIX}"
     sed -i -e "/LibDir.*Loader/s@return \"\/\"@return \"${EPREFIX%/}/\"@" Linux.cpp
     eend $?
-    ebegin "Remove --sysroot call on ld for native toolchain"
-    sed -i -e "$(grep -n -B1 sysroot= Gnu.cpp | sed -ne '{1s/-.*//;1p}'),+1 d" Gnu.cpp
-    eend $?
     popd >/dev/null
 elif [[ ${CATEGORY}/${PN} == sys-devel/binutils && ${EBUILD_PHASE} == prepare ]]; then
     ebegin "Prefixifying native library path"
diff --git a/sys-libs/glibc/glibc-2.36-r6.ebuild b/sys-libs/glibc/glibc-2.36-r6.ebuild
index be82be429c8f..e86bbd923123 100644
--- a/sys-libs/glibc/glibc-2.36-r6.ebuild
+++ b/sys-libs/glibc/glibc-2.36-r6.ebuild
@@ -1314,6 +1314,17 @@ glibc_do_src_install() {
 		mv "${ED}"/$(alt_usrlibdir)/libm-${upstream_pv}.a "${ED}"/$(alt_usrlibdir)/${P}/libm-${upstream_pv}.a || die
 	fi
 
+	# We configure toolchains for standalone prefix systems with a sysroot,
+	# which is prepended to paths in ld scripts, so strip the prefix from these.
+	# Before: GROUP ( /foo/lib64/libc.so.6 /foo/usr/lib64/libc_nonshared.a  AS_NEEDED ( /foo/lib64/ld-linux-x86-64.so.2 ) )
+	# After: GROUP ( /lib64/libc.so.6 /usr/lib64/libc_nonshared.a  AS_NEEDED ( /lib64/ld-linux-x86-64.so.2 ) )
+	if [[ -n $(host_eprefix) ]] ; then
+		local file
+		grep -lZIF "ld script" "${ED}/$(alt_usrlibdir)"/lib*.{a,so} 2>/dev/null | while read -rd '' file ; do
+			sed -i "s|$(host_eprefix)/|/|g" "${file}" || die
+		done
+	fi
+
 	# We'll take care of the cache ourselves
 	rm -f "${ED}"/etc/ld.so.cache
 
diff --git a/sys-libs/glibc/glibc-2.36-r7.ebuild b/sys-libs/glibc/glibc-2.36-r7.ebuild
index 7071aab6c547..6f93ac1992b1 100644
--- a/sys-libs/glibc/glibc-2.36-r7.ebuild
+++ b/sys-libs/glibc/glibc-2.36-r7.ebuild
@@ -1314,6 +1314,17 @@ glibc_do_src_install() {
 		mv "${ED}"/$(alt_usrlibdir)/libm-${upstream_pv}.a "${ED}"/$(alt_usrlibdir)/${P}/libm-${upstream_pv}.a || die
 	fi
 
+	# We configure toolchains for standalone prefix systems with a sysroot,
+	# which is prepended to paths in ld scripts, so strip the prefix from these.
+	# Before: GROUP ( /foo/lib64/libc.so.6 /foo/usr/lib64/libc_nonshared.a  AS_NEEDED ( /foo/lib64/ld-linux-x86-64.so.2 ) )
+	# After: GROUP ( /lib64/libc.so.6 /usr/lib64/libc_nonshared.a  AS_NEEDED ( /lib64/ld-linux-x86-64.so.2 ) )
+	if [[ -n $(host_eprefix) ]] ; then
+		local file
+		grep -lZIF "ld script" "${ED}/$(alt_usrlibdir)"/lib*.{a,so} 2>/dev/null | while read -rd '' file ; do
+			sed -i "s|$(host_eprefix)/|/|g" "${file}" || die
+		done
+	fi
+
 	# We'll take care of the cache ourselves
 	rm -f "${ED}"/etc/ld.so.cache
 
diff --git a/sys-libs/glibc/glibc-9999.ebuild b/sys-libs/glibc/glibc-9999.ebuild
index 413594ad57c4..23a25b3e5e13 100644
--- a/sys-libs/glibc/glibc-9999.ebuild
+++ b/sys-libs/glibc/glibc-9999.ebuild
@@ -1317,6 +1317,17 @@ glibc_do_src_install() {
 		mv "${ED}"/$(alt_usrlibdir)/libm-${upstream_pv}.a "${ED}"/$(alt_usrlibdir)/${P}/libm-${upstream_pv}.a || die
 	fi
 
+	# We configure toolchains for standalone prefix systems with a sysroot,
+	# which is prepended to paths in ld scripts, so strip the prefix from these.
+	# Before: GROUP ( /foo/lib64/libc.so.6 /foo/usr/lib64/libc_nonshared.a  AS_NEEDED ( /foo/lib64/ld-linux-x86-64.so.2 ) )
+	# After: GROUP ( /lib64/libc.so.6 /usr/lib64/libc_nonshared.a  AS_NEEDED ( /lib64/ld-linux-x86-64.so.2 ) )
+	if [[ -n $(host_eprefix) ]] ; then
+		local file
+		grep -lZIF "ld script" "${ED}/$(alt_usrlibdir)"/lib*.{a,so} 2>/dev/null | while read -rd '' file ; do
+			sed -i "s|$(host_eprefix)/|/|g" "${file}" || die
+		done
+	fi
+
 	# We'll take care of the cache ourselves
 	rm -f "${ED}"/etc/ld.so.cache