diff --git a/configure.ac b/configure.ac
index baa0bada6..d8195767e 100644
--- a/configure.ac
+++ b/configure.ac
@@ -435,6 +435,7 @@ CHARYBDIS_C_GCC_TRY_FLAGS([-Wrestrict], charybdis_cv_c_gcc_w_restrict)
 CHARYBDIS_C_GCC_TRY_FLAGS([-Wnull-dereference], charybdis_cv_c_gcc_w_null_dereference)
 CHARYBDIS_C_GCC_TRY_FLAGS([-Wplacement-new=2], charybdis_cv_c_gcc_w_placement_new)
 CHARYBDIS_C_GCC_TRY_FLAGS([-Wundef], charybdis_cv_c_gcc_w_undef)
+CHARYBDIS_C_GCC_TRY_FLAGS([-Wodr], charybdis_cv_c_gcc_w_odr)
 
 dnl
 dnl List of warnings we suppress: