diff --git a/src/configure b/src/configure
index 78e55fb7b..484a22961 100755
--- a/src/configure
+++ b/src/configure
@@ -3944,6 +3944,10 @@ else
   ECL_CC="${CXX}"
 fi
 
+if test "${GCC}" = "yes"; then
+  CFLAGS="${CFLAGS} -fstrict-aliasing"
+fi
+
 
   echo "$as_me:$LINENO: checking whether stack growns downwards" >&5
 echo $ECHO_N "checking whether stack growns downwards... $ECHO_C" >&6
diff --git a/src/configure.in b/src/configure.in
index d99595bc8..193a90d70 100644
--- a/src/configure.in
+++ b/src/configure.in
@@ -223,6 +223,13 @@ else
   ECL_CC="${CXX}"
 fi
 
+dnl ---------------------------------------------------------------------
+dnl		This flag is an optimization for GNU
+dnl ---------------------------------------------------------------------
+if test "${GCC}" = "yes"; then
+  CFLAGS="${CFLAGS} -fstrict-aliasing"
+fi
+
 dnl ----------------------------------------------------------------------
 dnl		Study the call conventions
 dnl