sql: too many autogenerated ids leads to SEGFAULT

This probleam appeared because region was cleaned twice: once in
sqlite3VdbeHalt() and once in sqlite3VdbeDelete() which was
executed during sqlite3_finalize(). Autogenerated ids that were
saved there, were fetched after sqlite3VdbeHalt() and before
sqlite3_finalize(). In this patch region cleaning in
sqlite3VdbeHalt() were removed.

Follow up #2618
Follow up #3199

src/box/sql/vdbe.c

@@ -2911,12 +2911,8 @@ case OP_MakeRecord: {
 	 * memory shouldn't be reused until it is written into WAL.
 	 *
 	 * However, if memory for ephemeral space is allocated
-	 * on region, it will be freed only in vdbeHalt() routine.
-	 * It is the only way to free this region memory,
-	 * since ephemeral spaces don't have nothing in common
-	 * with txn routine and region memory won't be released
-	 * after txn_commit() or txn_rollback() as it happens
-	 * with ordinary spaces.
+	 * on region, it will be freed only in sqlite3_finalize()
+	 * routine.
 	 */
 	if (bIsEphemeral) {
 		rc = sqlite3VdbeMemClearAndResize(pOut, nByte);

src/box/sql/vdbeaux.c

@@ -2498,12 +2498,6 @@ sqlite3VdbeHalt(Vdbe * p)
 		p->rc = SQLITE_NOMEM_BKPT;
 	}
 
-	/* Release all region memory which was allocated
-	 * to hold tuples to be inserted into ephemeral spaces.
-	 */
-	if (!box_txn())
-		fiber_gc();
-
 	assert(db->nVdbeActive > 0 || box_txn() ||
 	       p->anonymous_savepoint == NULL);
 	return (p->rc == SQLITE_BUSY ? SQLITE_BUSY : SQLITE_OK);

test/sql/iproto.result

@@ -794,6 +794,22 @@ res.rows
 - - [[{'name': 'space_id', 'type': 'unsigned'}, {'name': 'lsn', 'type': 'unsigned'},
       {'name': 'tuple', 'type': 'array'}]]
 ...
+-- Too many autogenerated ids leads to SEGFAULT.
+cn = remote.connect(box.cfg.listen)
+---
+...
+box.sql.execute('CREATE TABLE t1(id INTEGER PRIMARY KEY AUTOINCREMENT)')
+---
+...
+for i = 0, 1000 do cn:execute("INSERT INTO t1 VALUES (null)") end
+---
+...
+_ = cn:execute("INSERT INTO t1 SELECT NULL from t1")
+---
+...
+box.sql.execute('DROP TABLE t1')
+---
+...
 cn:close()
 ---
 ...

test/sql/iproto.test.lua

@@ -261,6 +261,13 @@ _ = cn:execute("EXPLAIN SELECT 1;")
 res = cn:execute('select "format" from "_space" limit 1;')
 res.rows
 
+-- Too many autogenerated ids leads to SEGFAULT.
+cn = remote.connect(box.cfg.listen)
+box.sql.execute('CREATE TABLE t1(id INTEGER PRIMARY KEY AUTOINCREMENT)')
+for i = 0, 1000 do cn:execute("INSERT INTO t1 VALUES (null)") end
+_ = cn:execute("INSERT INTO t1 SELECT NULL from t1")
+box.sql.execute('DROP TABLE t1')
+
 cn:close()
 
 box.schema.user.revoke('guest', 'read,write,execute', 'universe')