Update copyright for 2021

Backpatch-through: 9.5

src/backend/nodes/bitmapset.c

@@ -11,7 +11,7 @@
  * bms_is_empty() in preference to testing for NULL.)
  *
  *
- * Copyright (c) 2003-2020, PostgreSQL Global Development Group
+ * Copyright (c) 2003-2021, PostgreSQL Global Development Group
  *
  * IDENTIFICATION
  *	  src/backend/nodes/bitmapset.c

src/backend/nodes/copyfuncs.c

@@ -11,7 +11,7 @@
  * be handled easily in a simple depth-first traversal.
  *
  *
- * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION

src/backend/nodes/equalfuncs.c

@@ -18,7 +18,7 @@
  * "x" to be considered equal() to another reference to "x" in the query.
  *
  *
- * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION

src/backend/nodes/extensible.c

@@ -10,7 +10,7 @@
  * and GetExtensibleNodeMethods to get information about a previously
  * registered type of extensible node.
  *
- * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION

src/backend/nodes/list.c

@@ -6,7 +6,7 @@
  * See comments in pg_list.h.
  *
  *
- * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  *

src/backend/nodes/makefuncs.c

@@ -4,7 +4,7 @@
  *	  creator functions for various nodes. The functions here are for the
  *	  most frequently created nodes.
  *
- * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  *

src/backend/nodes/nodeFuncs.c

@@ -3,7 +3,7 @@
  * nodeFuncs.c
  *		Various general-purpose manipulations of Node trees
  *
- * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  *

src/backend/nodes/nodes.c

@@ -4,7 +4,7 @@
  *	  support code for nodes (now that we have removed the home-brew
  *	  inheritance system, our support code for nodes is much simpler)
  *
- * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  *

src/backend/nodes/outfuncs.c

@@ -3,7 +3,7 @@
  * outfuncs.c
  *	  Output functions for Postgres tree nodes.
  *
- * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  *

src/backend/nodes/params.c

@@ -4,7 +4,7 @@
  *	  Support for finding the values associated with Param nodes.
  *
  *
- * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION

src/backend/nodes/print.c

@@ -3,7 +3,7 @@
  * print.c
  *	  various print routines (used mostly for debugging)
  *
- * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  *

src/backend/nodes/read.c

@@ -4,7 +4,7 @@
  *	  routines to convert a string (legal ascii representation of node) back
  *	  to nodes
  *
- * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  *

src/backend/nodes/readfuncs.c

@@ -3,7 +3,7 @@
  * readfuncs.c
  *	  Reader functions for Postgres tree nodes.
  *
- * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  *

src/backend/nodes/tidbitmap.c

@@ -29,7 +29,7 @@
  * and a non-lossy page.
  *
  *
- * Copyright (c) 2003-2020, PostgreSQL Global Development Group
+ * Copyright (c) 2003-2021, PostgreSQL Global Development Group
  *
  * IDENTIFICATION
  *	  src/backend/nodes/tidbitmap.c

src/backend/nodes/value.c

@@ -4,7 +4,7 @@
  *	  implementation of Value nodes
  *
  *
- * Copyright (c) 2003-2020, PostgreSQL Global Development Group
+ * Copyright (c) 2003-2021, PostgreSQL Global Development Group
  *
  *
  * IDENTIFICATION