Fix pg_dump to dump casts between auto-generated types.

The heuristic for when to dump a cast failed for a cast between table
rowtypes, as reported by Frédéric Rejol.  Fix it by setting
the "dump" flag for such a type the same way as the flag is set for the
underlying table or base type.  This won't result in the auto-generated
type appearing in the output, since setting its objType to DO_DUMMY_TYPE
unconditionally suppresses that.  But it will result in dumpCast doing what
was intended.

Back-patch to 8.3.  The 8.2 code is rather different in this area, and it
doesn't seem worth any risk to fix a corner case that nobody has stumbled
on before.

src/bin/pg_dump/common.c

@@ -125,7 +125,7 @@ getSchemaData(int *numTablesPtr)
 	funinfo = getFuncs(&numFuncs);
 	funinfoindex = buildIndexArray(funinfo, numFuncs, sizeof(FuncInfo));
 
-	/* this must be after getFuncs */
+	/* this must be after getTables and getFuncs */
 	if (g_verbose)
 		write_msg(NULL, "reading user-defined types\n");
 	typinfo = getTypes(&numTypes);

src/bin/pg_dump/pg_dump.c

@@ -1093,8 +1093,11 @@ selectDumpableTable(TableInfo *tbinfo)
  * If it's a table's rowtype or an autogenerated array type, we also apply a
  * special type code to facilitate sorting into the desired order.	(We don't
  * want to consider those to be ordinary types because that would bring tables
- * up into the datatype part of the dump order.)  Those tests should be made
- * first to ensure the objType change is applied regardless of namespace etc.
+ * up into the datatype part of the dump order.)  We still set the object's
+ * dump flag; that's not going to cause the dummy type to be dumped, but we
+ * need it so that casts involving such types will be dumped correctly -- see
+ * dumpCast.  This means the flag should be set the same as for the underlying
+ * object (the table or base type).
  */
 static void
 selectDumpableType(TypeInfo *tyinfo)
@@ -1103,19 +1106,30 @@ selectDumpableType(TypeInfo *tyinfo)
 	if (OidIsValid(tyinfo->typrelid) &&
 		tyinfo->typrelkind != RELKIND_COMPOSITE_TYPE)
 	{
-		tyinfo->dobj.dump = false;
+		TableInfo  *tytable = findTableByOid(tyinfo->typrelid);
+
 		tyinfo->dobj.objType = DO_DUMMY_TYPE;
+		if (tytable != NULL)
+			tyinfo->dobj.dump = tytable->dobj.dump;
+		else
+			tyinfo->dobj.dump = false;
+		return;
 	}
 
 	/* skip auto-generated array types */
-	else if (tyinfo->isArray)
+	if (tyinfo->isArray)
 	{
-		tyinfo->dobj.dump = false;
 		tyinfo->dobj.objType = DO_DUMMY_TYPE;
+		/*
+		 * Fall through to set the dump flag; we assume that the subsequent
+		 * rules will do the same thing as they would for the array's base
+		 * type.  (We cannot reliably look up the base type here, since
+		 * getTypes may not have processed it yet.)
+		 */
 	}
 
 	/* dump only types in dumpable namespaces */
-	else if (!tyinfo->dobj.namespace->dobj.dump)
+	if (!tyinfo->dobj.namespace->dobj.dump)
 		tyinfo->dobj.dump = false;
 
 	/* skip undefined placeholder types */