Ensure prepared statement is finalized when an error occurs.

stmt.go

@@ -100,6 +100,7 @@ func (c *Conn) prepare(sql string, args ...interface{}) (*Stmt, error) {
 	// If the caller knows that the supplied string is nul-terminated, then there is a small performance advantage to be gained by passing an nByte parameter that is equal to the number of bytes in the input string including the nul-terminator bytes as this saves SQLite from having to make a copy of the input string.
 	rv := C.sqlite3_prepare_v2(c.db, sqlstr, C.int(len(sql)+1), &stmt, &tail)
 	if rv != C.SQLITE_OK {
+		C.sqlite3_finalize(stmt)
 		return nil, c.error(rv, sql)
 	}
 	var t string