diff --git a/configure.ac b/configure.ac
index da1a8f44..33bc9101 100644
--- a/configure.ac
+++ b/configure.ac
@@ -364,6 +364,9 @@ if test "$enable_debug" = yes ; then
       AC_CHECK_LIB([efence], [malloc])
     fi
   fi
+else
+  BIRD_CHECK_GCC_OPTION([bird_cv_c_option_wno_implicit_fallthrough], [-Wno-implicit-fallthrough])
+  BIRD_ADD_GCC_OPTION([bird_cv_c_option_wno_implicit_fallthrough], [-Wno-implicit-fallthrough])
 fi
 
 CLIENT=birdcl