diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index c50d1824304..44c2ed1a80a 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,10 @@
+2012-09-25  Jakub Jelinek  <jakub@redhat.com>
+
+	PR other/54692
+	* configure.ac (CFLAGS, CXXFLAGS): Remove -Ofast or -Og
+	properly.
+	* configure: Regenerated.
+
 2012-09-25  Georg-Johann Lay  <avr@gjlay.de>
 
 	PR other/54701
diff --git a/gcc/configure b/gcc/configure
index b656d9e5266..ff98a2254eb 100755
--- a/gcc/configure
+++ b/gcc/configure
@@ -4863,8 +4863,8 @@ fi
 # optimizations to be activated explicitly by the toplevel.
 case "$CC" in
   */prev-gcc/xgcc*) ;;
-  *) CFLAGS=`echo $CFLAGS | sed "s/-O[s0-9]* *//" `
-     CXXFLAGS=`echo $CXXFLAGS | sed "s/-O[s0-9]* *//" ` ;;
+  *) CFLAGS=`echo "$CFLAGS " | sed -e "s/-Ofast[ 	]//" -e "s/-O[gs][ 	]//" -e "s/-O[0-9]*[ 	]//" `
+     CXXFLAGS=`echo "$CXXFLAGS " | sed -e "s/-Ofast[ 	]//" -e "s/-O[gs][ 	]//" -e "s/-O[0-9]*[ 	]//" ` ;;
 esac
 
 
diff --git a/gcc/configure.ac b/gcc/configure.ac
index 5a260228973..453088e2fee 100644
--- a/gcc/configure.ac
+++ b/gcc/configure.ac
@@ -296,8 +296,8 @@ AC_SUBST(OUTPUT_OPTION)
 # optimizations to be activated explicitly by the toplevel.
 case "$CC" in
   */prev-gcc/xgcc*) ;;
-  *) CFLAGS=`echo $CFLAGS | sed "s/-O[[s0-9]]* *//" `
-     CXXFLAGS=`echo $CXXFLAGS | sed "s/-O[[s0-9]]* *//" ` ;;
+  *) CFLAGS=`echo "$CFLAGS " | sed -e "s/-Ofast[[ 	]]//" -e "s/-O[[gs]][[ 	]]//" -e "s/-O[[0-9]]*[[ 	]]//" `
+     CXXFLAGS=`echo "$CXXFLAGS " | sed -e "s/-Ofast[[ 	]]//" -e "s/-O[[gs]][[ 	]]//" -e "s/-O[[0-9]]*[[ 	]]//" ` ;;
 esac
 AC_SUBST(CFLAGS)
 AC_SUBST(CXXFLAGS)