diff --git a/src/configure.ac b/src/configure.ac
index e511b35..630433f 100644
--- a/src/configure.ac
+++ b/src/configure.ac
@@ -90,7 +90,7 @@
 dnl Set default value for CFLAGS if none is defined or it's empty
 if test -z "$CFLAGS"; then
   CFLAGS="-O"
-  test "$GCC" = yes && CFLAGS="-O2 -fno-strength-reduce -Wall"
+  test "$GCC" = yes && CFLAGS="-O2 -fno-strength-reduce -Wall -Wno-deprecated-declarations"
 fi
 if test "$GCC" = yes; then
   dnl method that should work for nearly all versions