[PATCH] Thread-safe libgfortran (PRs fortran/14943 and fortran/21647)

[Alan Modra]

On Wed, Nov 23, 2005 at 07:47:32AM +0100, FX Coudert wrote:
> >Is this an AIX specific problem?  I won't have time
> >until tomorrow (10 hours from now) to investigate.
> 
> No, it isn't. I won't have time now either (stupid public transportation 
> strike).

To make the review easier, here's the supporting evidence that my patch
is correct.  Jakub's patch did

-  u = find_file ();
-  if (u != NULL
+  u2 = NULL;
+  if ((opp->common.flags & IOPARM_OPEN_HAS_FILE) != 0)
+    u2 = find_file (opp->file, opp->file_len);
+  if (u2 != NULL
       && (options.stdin_unit < 0 || u->unit_number != options.stdin_unit)
       && (options.stdout_unit < 0 || u->unit_number != options.stdout_unit)
       && (options.stderr_unit < 0 || u->unit_number != options.stderr_unit

ie. before Jakub's patch, u was the same as the new u2, the gfc_unit of
an already open file.  u is now the new gfc_unit passed in from st_open.

And, just to make it obvious, 

(gdb) p *u2
$6 = {unit_number = 5, s = 0x100af640, left = 0x0, right = 0x0, 
  priority = 10821, read_bad = 0, current_record = 0, endfile = NO_ENDFILE, 
  mode = READING, flags = {access = ACCESS_SEQUENTIAL, action = ACTION_READ, 
    blank = BLANK_UNSPECIFIED, delim = DELIM_NONE, form = FORM_FORMATTED, 
    is_notpadded = 0, position = POSITION_ASIS, status = STATUS_OLD, 
    pad = PAD_YES}, recl = 1073741824, last_record = 0, maxrec = 0, 
  bytes_left = 0, lock = {__m_reserved = 0, __m_count = 0, __m_owner = 0x0, 
    __m_kind = 0, __m_lock = {__status = 0, __spinlock = 0}}, waiting = 0, 
  closed = 0, ls = 0x0, rank = 0, file_len = 0, file = 0x0}
(gdb) p *u
$7 = {unit_number = 10, s = 0x0, left = 0x0, right = 0x0, priority = 14047, 
  read_bad = 0, current_record = 0, endfile = NO_ENDFILE, mode = READING, 
  flags = {access = ACCESS_SEQUENTIAL, action = ACTION_READ, 
    blank = BLANK_NULL, delim = DELIM_NONE, form = FORM_FORMATTED, 
    is_notpadded = 0, position = POSITION_ASIS, status = STATUS_UNKNOWN, 
    pad = PAD_YES}, recl = 0, last_record = 0, maxrec = 0, bytes_left = 0, 
  lock = {__m_reserved = 0, __m_count = 0, __m_owner = 0x0, __m_kind = 0, 
    __m_lock = {__status = 0, __spinlock = 0}}, waiting = 0, closed = 0, 
  ls = 0x0, rank = 0, file_len = 0, file = 0x0}
(gdb) p *(options_t *)$r11  (don't ask me why p options didn't work!)
$8 = {stdin_unit = 5, stdout_unit = 6, stderr_unit = 0, optional_plus = 0, 
  allocate_init_flag = 0, allocate_init_value = 0, locus = 1, 
  separator_len = 1, separator = 0x1008c348 " ", mem_check = 0, 
  use_stderr = 1, all_unbuffered = 0, default_recl = 1073741824, 
  fpu_round = 0, fpu_precision = 0, fpe = 0, sighup = 0, sigint = 0}

-- 
Alan Modra
IBM OzLabs - Linux Technology Centre