Oversight in commit 
976b24fb4.
Andreas Seltenreich
Report: <87y448l3ag.fsf@credativ.de>
        int                     prettyFlags;
        RangeVar   *viewrel;
        Oid                     viewoid;
+       char       *res;
 
        prettyFlags = pretty ? PRETTYFLAG_PAREN | PRETTYFLAG_INDENT : PRETTYFLAG_INDENT;
 
        viewrel = makeRangeVarFromNameList(textToQualifiedNameList(viewname));
        viewoid = RangeVarGetRelid(viewrel, NoLock, false);
 
-       PG_RETURN_TEXT_P(string_to_text(pg_get_viewdef_worker(viewoid, prettyFlags, WRAP_COLUMN_DEFAULT)));
+       res = pg_get_viewdef_worker(viewoid, prettyFlags, WRAP_COLUMN_DEFAULT);
+
+       if (res == NULL)
+               PG_RETURN_NULL();
+
+       PG_RETURN_TEXT_P(string_to_text(res));
 }
 
 /*