diff --git a/configure b/configure
index b68776435c..46fd8bdf8c 100755
--- a/configure
+++ b/configure
@@ -4451,6 +4451,8 @@ if test "$gcov" = "yes" ; then
   LDFLAGS="-fprofile-arcs -ftest-coverage $LDFLAGS"
 elif test "$fortify_source" = "yes" ; then
   CFLAGS="-O2 -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2 $CFLAGS"
+elif test "$debug" = "no"; then
+  CFLAGS="-O2 $CFLAGS"
 fi
 
 ##########################################