diff --git a/src/vim9execute.c b/src/vim9execute.c
index 49336c0..9814f25 100644
--- a/src/vim9execute.c
+++ b/src/vim9execute.c
@@ -3345,10 +3345,12 @@
 		else
 		{
 		    exarg_T ea;
+		    char_u  *line_to_free = NULL;
 
 		    CLEAR_FIELD(ea);
 		    ea.cmd = ea.arg = iptr->isn_arg.string;
-		    define_function(&ea, NULL);
+		    define_function(&ea, NULL, &line_to_free);
+		    vim_free(line_to_free);
 		}
 		break;