Add some not null constraints to catalogs

Use BKI_FORCE_NOT_NULL on some catalog field declarations that are never
null (according to the source code that accesses them).

src/include/catalog/catversion.h

@@ -53,6 +53,6 @@
  */
 
 /*							yyyymmddN */
-#define CATALOG_VERSION_NO	201807191
+#define CATALOG_VERSION_NO	201808271
 
 #endif

src/include/catalog/pg_attrdef.h

@@ -32,8 +32,8 @@ CATALOG(pg_attrdef,2604,AttrDefaultRelationId)
 	int16		adnum;			/* attnum of attribute */
 
 #ifdef CATALOG_VARLEN			/* variable-length fields start here */
-	pg_node_tree adbin;			/* nodeToString representation of default */
-	text		adsrc;			/* human-readable representation of default */
+	pg_node_tree adbin BKI_FORCE_NOT_NULL;			/* nodeToString representation of default */
+	text		adsrc BKI_FORCE_NOT_NULL;			/* human-readable representation of default */
 #endif
 } FormData_pg_attrdef;
 

src/include/catalog/pg_default_acl.h

@@ -34,7 +34,7 @@ CATALOG(pg_default_acl,826,DefaultAclRelationId)
 	char		defaclobjtype;	/* see DEFACLOBJ_xxx constants below */
 
 #ifdef CATALOG_VARLEN			/* variable-length fields start here */
-	aclitem		defaclacl[1];	/* permissions to add at CREATE time */
+	aclitem		defaclacl[1] BKI_FORCE_NOT_NULL;	/* permissions to add at CREATE time */
 #endif
 } FormData_pg_default_acl;
 

src/include/catalog/pg_policy.h

@@ -34,7 +34,7 @@ CATALOG(pg_policy,3256,PolicyRelationId)
 	bool		polpermissive;	/* restrictive or permissive policy */
 
 #ifdef CATALOG_VARLEN
-	Oid			polroles[1];	/* Roles associated with policy, not-NULL */
+	Oid			polroles[1] BKI_FORCE_NOT_NULL;	/* Roles associated with policy */
 	pg_node_tree polqual;		/* Policy quals. */
 	pg_node_tree polwithcheck;	/* WITH CHECK quals. */
 #endif

src/include/catalog/pg_rewrite.h

@@ -38,8 +38,8 @@ CATALOG(pg_rewrite,2618,RewriteRelationId)
 	bool		is_instead;
 
 #ifdef CATALOG_VARLEN			/* variable-length fields start here */
-	pg_node_tree ev_qual;
-	pg_node_tree ev_action;
+	pg_node_tree ev_qual BKI_FORCE_NOT_NULL;
+	pg_node_tree ev_action BKI_FORCE_NOT_NULL;
 #endif
 } FormData_pg_rewrite;