Detect available lib64readline version before trying to install in chroot.

build/install-chroot.sh

 #!/bin/bash -e
 
 # Copyright (c) 2010 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # This script installs Debian-derived distributions in a chroot environment.
 # It can for example be used to have an accurate 32bit build and test
 # environment when otherwise working on a 64bit machine.
 # N. B. it is unlikely that this script will ever work on anything other than a
@@ skipping 238 matching lines @@
   echo '"'$(id -nu) ALL=(ALL) ALL'"' >>/etc/sudoers'
 
 # Install a few more commonly used packages
 sudo schroot -c "${target%bit}" -p -- apt-get -y install                       \
   autoconf automake1.9 dpkg-dev g++-multilib gcc-multilib gdb less libtool     \
   strace
 
 # If running a 32bit environment on a 64bit machine, install a few binaries
 # as 64bit.
 if [ "${arch}" = 32bit ] && file /bin/bash 2>/dev/null | grep -q x86-64; then
+  readlinepkg=$(sudo schroot -c "${target%bit}" -p -- sh -c \
+    'apt-cache search "lib64readline.\$" | sort | tail -n 1 | cut -d " " -f 1')
   sudo schroot -c "${target%bit}" -p -- apt-get -y install                     \
-    lib64expat1 lib64ncurses5 lib64readline6 lib64z1
+    lib64expat1 lib64ncurses5 ${readlinepkg} lib64z1
   dep=
   for i in binutils gdb strace; do
     [ -d /usr/share/doc/"$i" ] || dep="$dep $i"
   done
   [ -n "$dep" ] && sudo apt-get -y install $dep
   sudo cp /usr/bin/gdb "/var/lib/chroot/${target}/usr/local/bin/"
   sudo cp /usr/bin/ld "/var/lib/chroot/${target}/usr/local/bin/"
   for i in libbfd libpython; do
     lib="$({ ldd /usr/bin/ld; ldd /usr/bin/gdb; } |
            grep "$i" | awk '{ print $3 }')"
@@ skipping 18 matching lines @@
 
 Successfully installed ${distname} ${arch}
 
 You can run programs inside of the chroot by invoking the "${target%bit}"
 command.
 
 Your home directory is shared between the host and the chroot. But I configured
 $HOME/chroot to be private to the chroot environment. You can use it
 for files that need to differ between environments.
 EOF