Linux: Stop installing the gold linker as /usr/bin/ld. Ask users to pass -B/usr/local/gold/bin in...

build/install-build-deps.sh

 #!/bin/bash -e
 
 # Copyright (c) 2011 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
 
 usage() {
   echo "Usage: $0 [--options]"
   echo "Options:"
   echo "--[no-]syms: enable or disable installation of debugging symbols"
   echo "--[no-]gold: enable or disable installation of gold linker"
   echo "--[no-]lib32: enable or disable installation of 32 bit libraries"
+  echo "--[no-]restore-usr-bin-ld: enable or disable restoring /usr/bin/ld to"
+  echo "                           ld.bfd if it is currently gold"
   echo "Script will prompt interactively if options not given."
   exit 1
 }
 
 while test "$1" != ""
 do
   case "$1" in
-  --syms)     do_inst_syms=1;;
-  --no-syms)  do_inst_syms=0;;
-  --gold)     do_inst_gold=1;;
-  --no-gold)  do_inst_gold=0;;
-  --lib32)    do_inst_lib32=1;;
-  --no-lib32) do_inst_lib32=0;;
+  --syms)                   do_inst_syms=1;;
+  --no-syms)                do_inst_syms=0;;
+  --gold)                   do_inst_gold=1;;
+  --no-gold)                do_inst_gold=0;;
+  --lib32)                  do_inst_lib32=1;;
+  --no-lib32)               do_inst_lib32=0;;
+  --restore-usr-bin-ld)     do_restore_usr_bin_ld=1;;
+  --no-restore-usr-bin-ld)  do_restore_usr_bin_ld=0;;
   *) usage;;
   esac
   shift
 done
 
 install_gold() {
   # Gold is optional; it's a faster replacement for ld,
   # and makes life on 2GB machines much more pleasant.
 
   # First make sure root can access this directory, as that's tripped
@@ skipping 12 matching lines @@
 
   test -f $BINUTILS.tar.bz2 || wget $BINUTILS_URL
   if test "`sha1sum $BINUTILS.tar.bz2|cut -d' ' -f1`" != "$BINUTILS_SHA1"
   then
     echo Bad sha1sum for $BINUTILS.tar.bz2
     exit 1
   fi
 
   tar -xjvf $BINUTILS.tar.bz2
   cd $BINUTILS
-  ./configure --prefix=/usr/local/gold --enable-gold --enable-threads
-  make maybe-all-binutils maybe-all-gold -j4
-  if sudo make maybe-install-binutils maybe-install-gold
+  ./configure --prefix=/usr/local/gold --enable-gold=default --enable-threads \
+    --enable-bfd=yes
+  NCPU=`cat /proc/cpuinfo |grep ^processor|wc -l`
+  make maybe-all-binutils maybe-all-gold maybe-all-ld -j${NCPU}
+  if sudo make maybe-install-binutils maybe-install-gold maybe-install-ld
   then
     # Still need to figure out graceful way of pointing gyp to use
     # /usr/local/gold/bin/ld without requiring him to set environment
-    # variables.  That will go into bootstrap-linux.sh when it's ready.
-    echo "Installing gold as /usr/bin/ld."
-    echo "To uninstall, do 'cd /usr/bin; sudo rm ld; sudo mv ld.orig ld'"
-    test -f /usr/bin/ld && test ! -f /usr/bin/ld.orig && \
-        sudo mv /usr/bin/ld /usr/bin/ld.orig
-    sudo strip /usr/local/gold/bin/ld
-    sudo ln -fs /usr/local/gold/bin/ld /usr/bin/ld.gold
-    sudo ln -fs /usr/bin/ld.gold /usr/bin/ld
+    # variables.
+    sudo strip /usr/local/gold/bin/ld.gold
+    sudo strip /usr/local/gold/bin/ld.bfd
   else
     echo "make install failed, not installing gold"
   fi
 }
 
 if ! egrep -q \
     'Ubuntu (10\.04|10\.10|11\.04|lucid|maverick|natty)' \
     /etc/issue; then
   echo "Only Ubuntu 10.04 (lucid) through 11.04 (natty) are currently" \
       "supported" >&2
@@ skipping 159 matching lines @@
 fi
 
 # Some operating systems already ship gold (on recent Debian and
 # Ubuntu you can do "apt-get install binutils-gold" to get it), but
 # older releases didn't.  Additionally, gold 2.20 (included in Ubuntu
 # Lucid) makes binaries that just segfault, and 2.20.1 does not support
 # --map-whole-files.
 # So install from source if we don't have a good version.
 
 case `ld --version` in
+*gold*2.2[1-9].*)
+  echo "*** Warning ***"
+  echo "If the default linker is gold, linking may fail for:"
+  echo "the Linux kernel, kernel modules, Valgrind, and Wine."
+  echo "If you previously installed gold as the default linker,"
+  echo "you can restore the original linker by running:"
+  echo "'cd /usr/bin; sudo rm ld; sudo mv ld.orig ld'"
+  echo
+  if [ "$do_restore_usr_bin_ld" = "" ]
+  then
+    echo -n "Restore /usr/bin/ld to the original linker? (Y/n) "
+    if yes_no 0
+    then
+      do_restore_usr_bin_ld=1
+    fi
+    echo
+  fi
+  if [ "$do_restore_usr_bin_ld" = "1" ]
+  then
+    if sudo mv /usr/bin/ld.orig /usr/bin/ld
+    then
+      echo "Restored /usr/bin/ld.orig as /usr/bin/ld"
+    else
+      echo "Failed to restore /usr/bin/ld.orig as /usr/bin/ld"
+    fi
+    echo
+  fi
+  ;;
+esac
+
+# Check the gold version first.
+gold_up_to_date="1"
+case `/usr/local/gold/bin/ld --version` in
 *gold*2.2[1-9].*) ;;
 * )
+  gold_up_to_date="0"
+esac
+
+# Then check and make sure ld.bfd exists.
+if [ "$gold_up_to_date" = "1" ] && [ ! -x "/usr/local/gold/bin/ld.bfd" ]
+then
+  gold_up_to_date="0"
+fi
+
+if [ "$gold_up_to_date" = "0" ]
+then
   if test "$do_inst_gold" = ""
   then
-    echo "Gold is a new linker that links Chrome 5x faster than ld."
-    echo "Don't use it if you need to link other apps (e.g. valgrind, wine)"
-    echo -n "REPLACE SYSTEM LINKER ld with gold and back up ld? (y/N) "
+    echo "Gold is a new linker that links Chrome 5x faster than GNU ld."
+    echo -n "*** To use the gold linker, "
+    echo "you must pass -B/usr/local/gold/bin/ to g++ ***"
+    echo -n "Install the gold linker? (y/N) "
     if yes_no 1; then
       do_inst_gold=1
     fi
   fi
   if test "$do_inst_gold" = "1"
   then
     # If the system provides a good version of gold, just install it.
     if apt-cache show binutils-gold | grep -Eq 'Version: 2.2[1-9].*'; then
       echo "Installing binutils-gold. Backing up ld as ld.single."
       sudo apt-get install binutils-gold
     else
-      # FIXME: avoid installing as /usr/bin/ld
-      echo "Building binutils. Backing up ld as ld.orig."
+      echo "Building binutils with gold..."
       install_gold || exit 99
     fi
   else
     echo "Not installing gold."
   fi
-esac
+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
     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"
@@ skipping 165 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