Deprecate installing 32bit build dependencies on a 64bit

build/install-build-deps.sh

 #!/bin/bash -e
 
 # Copyright (c) 2012 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.
 
 # Script to install everything needed to build chromium (well, ideally, anyway)
 # See http://code.google.com/p/chromium/wiki/LinuxBuildInstructions
 # and http://code.google.com/p/chromium/wiki/LinuxBuild64Bit
 
@@ skipping 193 matching lines @@
   echo
   echo "You will have to install the above packages yourself."
   echo
   exit 100
 fi
 
 # Install 32bit backwards compatibility support for 64bit systems
 if [ "$(uname -m)" = "x86_64" ]; then
   if test "$do_inst_lib32" = ""
   then
-    echo "Installing 32bit libraries not already provided by the system"
+    echo "We no longer recommend that you use this script to install"
+    echo "32bit libraries on a 64bit system. Instead, consider using"
+    echo "the install-chroot.sh script to help you set up a 32bit"
+    echo "environment for building and testing 32bit versions of Chrome."
     echo
-    echo "This is only needed to build a 32-bit Chrome on your 64-bit system."
-    echo
-    echo "While we only need to install a relatively small number of library"
-    echo "files, we temporarily need to download a lot of large *.deb packages"
-    echo "that contain these files. We will create new *.deb packages that"
-    echo "include just the 32bit libraries. These files will then be found on"
-    echo "your system in places like /lib32, /usr/lib32, /usr/lib/debug/lib32,"
-    echo "/usr/lib/debug/usr/lib32. If you ever need to uninstall these files,"
-    echo "look for packages named *-ia32.deb."
-    echo "Do you want me to download all packages needed to build new 32bit"
-    echo -n "package files (y/N) "
-    if yes_no 1; then
-      do_inst_lib32=1
-    fi
+    echo "If you nonetheless want to try installing 32bit libraries"
+    echo "directly, you can do so by explicitly passing the --lib32"
+    echo "option to install-build-deps.sh.
   fi
   if test "$do_inst_lib32" != "1"
   then
     echo "Exiting without installing any 32bit libraries."
     exit 0
   fi
 
+  echo "N.B. the code for installing 32bit libraries on a 64bit"
+  echo "     system is no longer actively maintained and might"
+  echo "     not work with modern versions of Ubuntu or Debian."
+  echo
+
   # Standard 32bit compatibility libraries
   echo "First, installing the limited existing 32-bit support..."
   cmp_list="ia32-libs lib32asound2-dev lib32stdc++6 lib32z1
             lib32z1-dev libc6-dev-i386 libc6-i386 g++-multilib"
   if [ -n "`apt-cache search lib32readline-gplv2-dev 2>/dev/null`" ]; then
     cmp_list="${cmp_list} lib32readline-gplv2-dev"
   else
     cmp_list="${cmp_list} lib32readline5-dev"
   fi
   sudo apt-get install $cmp_list
@@ skipping 142 matching lines @@
              sed -e 's/[.]so[.][0-9].*/.so/' |
              sort -u); do
     [ "x${i##*/}" = "xld-linux.so" ] && continue
     [ -r "$i" ] && continue
     j="$(ls "$i."* | sed -e 's/.*[.]so[.]\([^.]*\)$/\1/;t;d' |
          sort -n | tail -n 1)"
     [ -r "$i.$j" ] || continue
     sudo ln -s "${i##*/}.$j" "$i"
   done
 fi