Fix core dump in pg_dump --binary-upgrade on zero-column composite type.

This reverts nearly all of commit 28f6cab61ab8958b1a7dfb019724687d92722538
in favor of just using the typrelid we already have in pg_dump's TypeInfo
struct for the composite type.  As coded, it'd crash if the composite type
had no attributes, since then the query would return no rows.

Back-patch to all supported versions.  It seems to not really be a problem
in 9.0 because that version rejects the syntax "create type t as ()", but
we might as well keep the logic similar in all affected branches.

Report and fix by Rushabh Lathia.

diff --git a/src/bin/pg_dump/pg_dump.c b/src/bin/pg_dump/pg_dump.c
index 089f77ab34aefc457634517501b40f800350c46a..1e8f089224c5160a9edc756b51a2ab825ac9906e 100644 (file)
--- a/src/bin/pg_dump/pg_dump.c
+++ b/src/bin/pg_dump/pg_dump.c
@@ -9273,7 +9273,6 @@ dumpCompositeType(Archive *fout, DumpOptions *dopt, TypeInfo *tyinfo)
    int         i_attalign;
    int         i_attisdropped;
    int         i_attcollation;
-   int         i_typrelid;
    int         i;
    int         actual_atts;
 
@@ -9294,8 +9293,7 @@ dumpCompositeType(Archive *fout, DumpOptions *dopt, TypeInfo *tyinfo)
            "pg_catalog.format_type(a.atttypid, a.atttypmod) AS atttypdefn, "
                          "a.attlen, a.attalign, a.attisdropped, "
                          "CASE WHEN a.attcollation <> at.typcollation "
-                         "THEN a.attcollation ELSE 0 END AS attcollation, "
-                         "ct.typrelid "
+                         "THEN a.attcollation ELSE 0 END AS attcollation "
                          "FROM pg_catalog.pg_type ct "
                "JOIN pg_catalog.pg_attribute a ON a.attrelid = ct.typrelid "
                    "LEFT JOIN pg_catalog.pg_type at ON at.oid = a.atttypid "
@@ -9313,8 +9311,7 @@ dumpCompositeType(Archive *fout, DumpOptions *dopt, TypeInfo *tyinfo)
        appendPQExpBuffer(query, "SELECT a.attname, "
            "pg_catalog.format_type(a.atttypid, a.atttypmod) AS atttypdefn, "
                          "a.attlen, a.attalign, a.attisdropped, "
-                         "0 AS attcollation, "
-                         "ct.typrelid "
+                         "0 AS attcollation "
                     "FROM pg_catalog.pg_type ct, pg_catalog.pg_attribute a "
                          "WHERE ct.oid = '%u'::pg_catalog.oid "
                          "AND a.attrelid = ct.typrelid "
@@ -9332,15 +9329,12 @@ dumpCompositeType(Archive *fout, DumpOptions *dopt, TypeInfo *tyinfo)
    i_attalign = PQfnumber(res, "attalign");
    i_attisdropped = PQfnumber(res, "attisdropped");
    i_attcollation = PQfnumber(res, "attcollation");
-   i_typrelid = PQfnumber(res, "typrelid");
 
    if (dopt->binary_upgrade)
    {
-       Oid         typrelid = atooid(PQgetvalue(res, 0, i_typrelid));
-
        binary_upgrade_set_type_oids_by_type_oid(fout, q,
                                                 tyinfo->dobj.catId.oid);
-       binary_upgrade_set_pg_class_oids(fout, q, typrelid, false);
+       binary_upgrade_set_pg_class_oids(fout, q, tyinfo->typrelid, false);
    }
 
    qtypname = pg_strdup(fmtId(tyinfo->dobj.name));