diff --git a/src/_tkagg.cpp b/src/_tkagg.cpp
index 1d690f4f4e00..7be9ad2fcbd9 100644
--- a/src/_tkagg.cpp
+++ b/src/_tkagg.cpp
@@ -114,7 +114,7 @@ static int PyAggImagePhoto(ClientData clientdata, Tcl_Interp *interp, int
         try {
             destbuffer = new agg::int8u[deststride * destheight];
         }
-        catch (std::bad_alloc) {
+        catch (const std::bad_alloc &) {
             TCL_APPEND_RESULT(interp, "could not allocate memory", (char *)NULL);
             return TCL_ERROR;
         }