Fix EXIT out of outermost block in plpgsql.

Ordinarily, using EXIT this way would draw "control reached end of
function without RETURN".  However, if the function is one where we
don't require an explicit RETURN (such as a DO block), that should
not happen.  It did anyway, because add_dummy_return() neglected to
account for the case.

Per report from Herwig Goemans.  Back-patch to all supported branches.

Discussion: https://postgr.es/m/868ae948-e3ca-c7ec-95a6-83cfc08ef750@gmail.com

diff --git a/src/pl/plpgsql/src/pl_comp.c b/src/pl/plpgsql/src/pl_comp.c
index 75249b3ec8e72a98fe6c99016dcd81e5521a1d9d..e88c1ac551e7e10cfebb4d3cf36613878f2d10e1 100644 (file)
--- a/src/pl/plpgsql/src/pl_comp.c
+++ b/src/pl/plpgsql/src/pl_comp.c
@@ -976,9 +976,11 @@ add_dummy_return(PLpgSQL_function *function)
    /*
     * If the outer block has an EXCEPTION clause, we need to make a new outer
     * block, since the added RETURN shouldn't act like it is inside the
-    * EXCEPTION clause.
+    * EXCEPTION clause.  Likewise, if it has a label, wrap it in a new outer
+    * block so that EXIT doesn't skip the RETURN.
     */
-   if (function->action->exceptions != NULL)
+   if (function->action->exceptions != NULL ||
+       function->action->label != NULL)
    {
        PLpgSQL_stmt_block *new;