Remove no-longer-needed loop in ExecGather().

Coverity complained quite properly that commit ea15e1867 had introduced
unreachable code into ExecGather(); to wit, it was no longer possible to
iterate the final for-loop more or less than once.  So remove the for().

In passing, clean up a couple of comments, and make better use of a local
variable.

diff --git a/src/backend/executor/nodeGather.c b/src/backend/executor/nodeGather.c
index 45aa1132d92271e9a65c9beeacfe7e2196af2d13..a1a3561d48c101e80cd3fcbefc279f3d6e5a5ab1 100644 (file)
--- a/src/backend/executor/nodeGather.c
+++ b/src/backend/executor/nodeGather.c
@@ -135,8 +135,8 @@ ExecGather(GatherState *node)
    /*
     * Initialize the parallel context and workers on first execution. We do
     * this on first execution rather than during node initialization, as it
-    * needs to allocate large dynamic segment, so it is better to do if it is
-    * really needed.
+    * needs to allocate a large dynamic segment, so it is better to do it
+    * only if it is really needed.
     */
    if (!node->initialized)
    {
@@ -201,32 +201,23 @@ ExecGather(GatherState *node)
     * any previous tuple returned by a TupleQueueReader; to make sure we
     * don't leave a dangling pointer around, clear the working slot first.
     */
-   ExecClearTuple(node->funnel_slot);
+   ExecClearTuple(fslot);
    econtext = node->ps.ps_ExprContext;
    ResetExprContext(econtext);
 
-   /* Get and return the next tuple, projecting if necessary. */
-   for (;;)
-   {
-       /*
-        * Get next tuple, either from one of our workers, or by running the
-        * plan ourselves.
-        */
-       slot = gather_getnext(node);
-       if (TupIsNull(slot))
-           return NULL;
-
-       /*
-        * form the result tuple using ExecProject(), and return it --- unless
-        * the projection produces an empty set, in which case we must loop
-        * back around for another tuple
-        */
-       econtext->ecxt_outertuple = slot;
-
-       return ExecProject(node->ps.ps_ProjInfo);
-   }
+   /*
+    * Get next tuple, either from one of our workers, or by running the plan
+    * ourselves.
+    */
+   slot = gather_getnext(node);
+   if (TupIsNull(slot))
+       return NULL;
 
-   return slot;
+   /*
+    * Form the result tuple using ExecProject(), and return it.
+    */
+   econtext->ecxt_outertuple = slot;
+   return ExecProject(node->ps.ps_ProjInfo);
 }
 
 /* ----------------------------------------------------------------