diff --git a/src/mesa/program/program_parse.y b/src/mesa/program/program_parse.y
index ba4757ff74e..0f5fdcb4f84 100644
--- a/src/mesa/program/program_parse.y
+++ b/src/mesa/program/program_parse.y
@@ -684,6 +684,7 @@ extSwizSel: INTEGER
 
       if (strlen($1) > 1) {
          yyerror(& @1, state, "invalid extended swizzle selector");
+         free($1);
          YYERROR;
       }