Should be virtual inheritance.

diff --git a/saml/saml2/metadata/ObservableMetadataProvider.h b/saml/saml2/metadata/ObservableMetadataProvider.h
index f652f73..ab47da3 100644 (file)
--- a/saml/saml2/metadata/ObservableMetadataProvider.h
+++ b/saml/saml2/metadata/ObservableMetadataProvider.h
@@ -40,7 +40,7 @@ namespace opensaml {
         /**
          * A metadata provider that notifies interested parties of changes.
          */
-        class SAML_API ObservableMetadataProvider : public MetadataProvider
+        class SAML_API ObservableMetadataProvider : public virtual MetadataProvider
         {
         protected:
             /**