re PR libfortran/92100 (Formatted stream IO irreproducible read with binary data in file)

2019-11-24  Jerry DeLisle  <jvdelisle@gcc.ngu.org>

	PR fortran/92100
	io/transfer.c (data_transfer_init_worker): Use fbuf_reset
	instead of fbuf_flush before the seek. Note that fbuf_reset
	calls fbuf_flush and adjusts fbuf pointers.

From-SVN: r278660

libgfortran/ChangeLog

+2019-11-24  Jerry DeLisle  <jvdelisle@gcc.ngu.org>
+
+	PR fortran/92100
+	io/transfer.c (data_transfer_init_worker): Use fbuf_reset
+	instead of fbuf_flush before the seek. Note that fbuf_reset
+	calls fbuf_flush and adjusts fbuf pointers.
+
 2019-11-23  Thomas Koenig  <tkoenig@gcc.gnu.org>
 	Harald Anlauf <anlauf@gmx.de>
 

libgfortran/io/transfer.c

@@ -3309,8 +3309,9 @@ data_transfer_init_worker (st_parameter_dt *dtp, int read_flag)
 
           if (dtp->pos != dtp->u.p.current_unit->strm_pos)
             {
-              fbuf_flush (dtp->u.p.current_unit, dtp->u.p.mode);
-              if (sseek (dtp->u.p.current_unit->s, dtp->pos - 1, SEEK_SET) < 0)
+	      fbuf_reset (dtp->u.p.current_unit);
+	      if (sseek (dtp->u.p.current_unit->s, dtp->pos - 1,
+			 SEEK_SET) < 0)
                 {
                   generate_error (&dtp->common, LIBERROR_OS, NULL);
                   return;