------- Comment #3 from burnus at gcc dot gnu dot org 2007-03-09 12:55 -------
I was checking where bytes_left is set:
open.c: u->bytes_left = 0;
This is the default setting in new_unit (/* Open an unused unit. */)
It is also set to 0 in file_pos.c (two places).
In list_read.c's next_char it is set to current_unit->recl;
And in transfer.c:
- read_block
- write_block (but only if stdout/stderr or default reclen, otherwise a
ERROR_EOR error is generated, but this is not the error of this PR.)
- us_read
- us_write: This one is also not called for this PR
- next_record_w: Not for unformatted
The problem seems to be that bytes_left == 0 from the initial setting in
new_unit as no data has been written. And as 4bytes have to be written, nbytes
= 4 > bytes_left.
Note: The same problem occurs if one tries to read from a file which has been
written by gfortran-4.1. In this case the error condition is in:
transfer.c's read_block_direct:
if (dtp->u.p.current_unit->flags.has_recl)
{
to_read_record =
*nbytes > (size_t) dtp->u.p.current_unit->bytes_left ?
*nbytes : (size_t) dtp->u.p.current_unit->bytes_left;
short_record = 1;
}
else
{
to_read_record = *nbytes;
short_record = 0;
}
This check has been introduced by the same patch.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31099
