+
+#if defined(XMLTOOLING_LOG4SHIB)
+# ifndef OPENSAML_LOG4SHIB
+# error "Logging library mismatch (XMLTooling is using log4shib)."
+# endif
+#elif defined(XMLTOOLING_LOG4CPP)
+# ifndef OPENSAML_LOG4CPP
+# error "Logging library mismatch (XMLTooling is using log4cpp)."
+# endif
+#else
+# error "No supported logging library."
+#endif
+