diff --git a/config/ChangeLog b/config/ChangeLog
index 6e30188b9f..b7f81e3b6a 100644
--- a/config/ChangeLog
+++ b/config/ChangeLog
@@ -1,5 +1,15 @@
 2018-10-31  Joseph Myers  <joseph@codesourcery.com>
 
+	Merge from GCC:
+	2018-10-28  Iain Buclaw  <ibuclaw@gdcproject.org>
+
+	* multi.m4: Set GDC.
+
+	2018-07-05  James Clarke  <jrtc27@jrtc27.com>
+
+	* dfp.m4 (enable_decimal_float): Enable for x86_64*-*-gnu* to
+	catch x86_64 kFreeBSD and Hurd.
+
 	Merge from GCC:
 	PR bootstrap/82856
 	* math.m4, tls.m4: Use AC_LANG_SOURCE.
diff --git a/config/dfp.m4 b/config/dfp.m4
index 5b29089cec..a137ddebf8 100644
--- a/config/dfp.m4
+++ b/config/dfp.m4
@@ -21,7 +21,7 @@ Valid choices are 'yes', 'bid', 'dpd', and 'no'.]) ;;
 [
   case $1 in
     powerpc*-*-linux* | i?86*-*-linux* | x86_64*-*-linux* | s390*-*-linux* | \
-    i?86*-*-elfiamcu | i?86*-*-gnu* | \
+    i?86*-*-elfiamcu | i?86*-*-gnu* | x86_64*-*-gnu* | \
     i?86*-*-mingw* | x86_64*-*-mingw* | \
     i?86*-*-cygwin* | x86_64*-*-cygwin*)
       enable_decimal_float=yes
diff --git a/config/multi.m4 b/config/multi.m4
index bba338a826..10680a5b32 100644
--- a/config/multi.m4
+++ b/config/multi.m4
@@ -64,4 +64,5 @@ multi_basedir="$multi_basedir"
 CONFIG_SHELL=${CONFIG_SHELL-/bin/sh}
 CC="$CC"
 CXX="$CXX"
-GFORTRAN="$GFORTRAN"])])dnl
+GFORTRAN="$GFORTRAN"
+GDC="$GDC"])])dnl
diff --git a/libdecnumber/ChangeLog b/libdecnumber/ChangeLog
index 950cde5e27..58be97d524 100644
--- a/libdecnumber/ChangeLog
+++ b/libdecnumber/ChangeLog
@@ -1,3 +1,7 @@
+2018-10-31  Joseph Myers  <joseph@codesourcery.com>
+
+	* configure: Regenerate.
+
 2018-06-19  Simon Marchi  <simon.marchi@ericsson.com>
 
 	* configure.ac: Remove AC_PREREQ.
diff --git a/libdecnumber/configure b/libdecnumber/configure
index e324267457..6e672c785e 100755
--- a/libdecnumber/configure
+++ b/libdecnumber/configure
@@ -4765,7 +4765,7 @@ else
 
   case $target in
     powerpc*-*-linux* | i?86*-*-linux* | x86_64*-*-linux* | s390*-*-linux* | \
-    i?86*-*-elfiamcu | i?86*-*-gnu* | \
+    i?86*-*-elfiamcu | i?86*-*-gnu* | x86_64*-*-gnu* | \
     i?86*-*-mingw* | x86_64*-*-mingw* | \
     i?86*-*-cygwin* | x86_64*-*-cygwin*)
       enable_decimal_float=yes
diff --git a/zlib/ChangeLog.bin-gdb b/zlib/ChangeLog.bin-gdb
index f113fc6a22..2b48b0211f 100644
--- a/zlib/ChangeLog.bin-gdb
+++ b/zlib/ChangeLog.bin-gdb
@@ -1,5 +1,7 @@
 2018-10-31  Joseph Myers  <joseph@codesourcery.com>
 
+	* configure: Regenerate.
+
 	Merge from GCC.
 	PR bootstrap/82856
 	* Makefile.am: Include multilib.am.
diff --git a/zlib/configure b/zlib/configure
index 5e1e1bb767..041cbdbf71 100755
--- a/zlib/configure
+++ b/zlib/configure
@@ -12228,6 +12228,7 @@ CONFIG_SHELL=${CONFIG_SHELL-/bin/sh}
 CC="$CC"
 CXX="$CXX"
 GFORTRAN="$GFORTRAN"
+GDC="$GDC"
 AMDEP_TRUE="$AMDEP_TRUE" ac_aux_dir="$ac_aux_dir"