diff --git a/src/api/z3_replayer.cpp b/src/api/z3_replayer.cpp
index aebc2f9a5..92f2c2d6a 100644
--- a/src/api/z3_replayer.cpp
+++ b/src/api/z3_replayer.cpp
@@ -80,7 +80,7 @@ struct z3_replayer::imp {
             strm << "expecting " << kind2string(k) << " at position "
                  << pos << " but got " << kind2string(m_args[pos].m_kind);
             TRACE("z3_replayer", tout << strm.str() << "\n";);
-            throw z3_replayer_exception(strm.str());
+            throw z3_replayer_exception(std::move(strm).str());
         }
     }
 
@@ -529,6 +529,9 @@ struct z3_replayer::imp {
                 catch (z3_error & ex) {
                     throw ex;
                 }
+                catch (z3_replayer_exception &) {
+                    throw;
+                }
                 catch (z3_exception & ex) {
                     std::cout << "[z3 exception]: " << ex.msg() << std::endl;
                 }