CbC/CbC_gcc: gcc/fortran/io.c comparison

comparison gcc/fortran/io.c @ 111:04ced10e8804

gcc 7

author	kono
date	Fri, 27 Oct 2017 22:46:09 +0900
parents
children	84e7813d76e9

comparison

equal deleted inserted replaced

-:561a7518be6b
+:04ced10e8804
+/* Deal with I/O statements & related stuff.
+Copyright (C) 2000-2017 Free Software Foundation, Inc.
+Contributed by Andy Vaught
+This file is part of GCC.
+GCC is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 3, or (at your option) any later
+version.
+GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+for more details.
+You should have received a copy of the GNU General Public License
+along with GCC; see the file COPYING3.  If not see
+<http://www.gnu.org/licenses/>.  */
+#include "config.h"
+#include "system.h"
+#include "coretypes.h"
+#include "options.h"
+#include "gfortran.h"
+#include "match.h"
+#include "parse.h"
+gfc_st_label
+format_asterisk = {0, NULL, NULL, -1, ST_LABEL_FORMAT, ST_LABEL_FORMAT, NULL,
+		   0, {NULL, NULL}, NULL};
+typedef struct
+{
+const char *name, *spec, *value;
+bt type;
+}
+io_tag;
+static const io_tag
+	tag_readonly	= {"READONLY", " readonly", NULL, BT_UNKNOWN },
+	tag_shared	= {"SHARE", " shared", NULL, BT_UNKNOWN },
+	tag_noshared	= {"SHARE", " noshared", NULL, BT_UNKNOWN },
+	tag_e_share	= {"SHARE", " share =", " %e", BT_CHARACTER },
+	tag_v_share	= {"SHARE", " share =", " %v", BT_CHARACTER },
+	tag_cc		= {"CARRIAGECONTROL", " carriagecontrol =", " %e",
+			   BT_CHARACTER },
+	tag_v_cc	= {"CARRIAGECONTROL", " carriagecontrol =", " %v",
+			   BT_CHARACTER },
+	tag_file	= {"FILE", " file =", " %e", BT_CHARACTER },
+	tag_status	= {"STATUS", " status =", " %e", BT_CHARACTER},
+	tag_e_access	= {"ACCESS", " access =", " %e", BT_CHARACTER},
+	tag_e_form	= {"FORM", " form =", " %e", BT_CHARACTER},
+	tag_e_recl	= {"RECL", " recl =", " %e", BT_INTEGER},
+	tag_e_blank	= {"BLANK", " blank =", " %e", BT_CHARACTER},
+	tag_e_position	= {"POSITION", " position =", " %e", BT_CHARACTER},
+	tag_e_action	= {"ACTION", " action =", " %e", BT_CHARACTER},
+	tag_e_delim	= {"DELIM", " delim =", " %e", BT_CHARACTER},
+	tag_e_pad	= {"PAD", " pad =", " %e", BT_CHARACTER},
+	tag_e_decimal	= {"DECIMAL", " decimal =", " %e", BT_CHARACTER},
+	tag_e_encoding	= {"ENCODING", " encoding =", " %e", BT_CHARACTER},
+	tag_e_async	= {"ASYNCHRONOUS", " asynchronous =", " %e", BT_CHARACTER},
+	tag_e_round	= {"ROUND", " round =", " %e", BT_CHARACTER},
+	tag_e_sign	= {"SIGN", " sign =", " %e", BT_CHARACTER},
+	tag_unit	= {"UNIT", " unit =", " %e", BT_INTEGER},
+	tag_advance	= {"ADVANCE", " advance =", " %e", BT_CHARACTER},
+	tag_rec		= {"REC", " rec =", " %e", BT_INTEGER},
+	tag_spos	= {"POSITION", " pos =", " %e", BT_INTEGER},
+	tag_format	= {"FORMAT", NULL, NULL, BT_CHARACTER},
+	tag_iomsg	= {"IOMSG", " iomsg =", " %e", BT_CHARACTER},
+	tag_iostat	= {"IOSTAT", " iostat =", " %v", BT_INTEGER},
+	tag_size	= {"SIZE", " size =", " %v", BT_INTEGER},
+	tag_exist	= {"EXIST", " exist =", " %v", BT_LOGICAL},
+	tag_opened	= {"OPENED", " opened =", " %v", BT_LOGICAL},
+	tag_named	= {"NAMED", " named =", " %v", BT_LOGICAL},
+	tag_name	= {"NAME", " name =", " %v", BT_CHARACTER},
+	tag_number	= {"NUMBER", " number =", " %v", BT_INTEGER},
+	tag_s_access	= {"ACCESS", " access =", " %v", BT_CHARACTER},
+	tag_sequential	= {"SEQUENTIAL", " sequential =", " %v", BT_CHARACTER},
+	tag_direct	= {"DIRECT", " direct =", " %v", BT_CHARACTER},
+	tag_s_form	= {"FORM", " form =", " %v", BT_CHARACTER},
+	tag_formatted	= {"FORMATTED", " formatted =", " %v", BT_CHARACTER},
+	tag_unformatted	= {"UNFORMATTED", " unformatted =", " %v", BT_CHARACTER},
+	tag_s_recl	= {"RECL", " recl =", " %v", BT_INTEGER},
+	tag_nextrec	= {"NEXTREC", " nextrec =", " %v", BT_INTEGER},
+	tag_s_blank	= {"BLANK", " blank =", " %v", BT_CHARACTER},
+	tag_s_position	= {"POSITION", " position =", " %v", BT_CHARACTER},
+	tag_s_action	= {"ACTION", " action =", " %v", BT_CHARACTER},
+	tag_read	= {"READ", " read =", " %v", BT_CHARACTER},
+	tag_write	= {"WRITE", " write =", " %v", BT_CHARACTER},
+	tag_readwrite	= {"READWRITE", " readwrite =", " %v", BT_CHARACTER},
+	tag_s_delim	= {"DELIM", " delim =", " %v", BT_CHARACTER},
+	tag_s_pad	= {"PAD", " pad =", " %v", BT_CHARACTER},
+	tag_s_decimal	= {"DECIMAL", " decimal =", " %v", BT_CHARACTER},
+	tag_s_encoding	= {"ENCODING", " encoding =", " %v", BT_CHARACTER},
+	tag_s_async	= {"ASYNCHRONOUS", " asynchronous =", " %v", BT_CHARACTER},
+	tag_s_round	= {"ROUND", " round =", " %v", BT_CHARACTER},
+	tag_s_sign	= {"SIGN", " sign =", " %v", BT_CHARACTER},
+	tag_iolength	= {"IOLENGTH", " iolength =", " %v", BT_INTEGER},
+	tag_convert     = {"CONVERT", " convert =", " %e", BT_CHARACTER},
+	tag_strm_out    = {"POS", " pos =", " %v", BT_INTEGER},
+	tag_err		= {"ERR", " err =", " %l", BT_UNKNOWN},
+	tag_end		= {"END", " end =", " %l", BT_UNKNOWN},
+	tag_eor		= {"EOR", " eor =", " %l", BT_UNKNOWN},
+	tag_id		= {"ID", " id =", " %v", BT_INTEGER},
+	tag_pending	= {"PENDING", " pending =", " %v", BT_LOGICAL},
+	tag_newunit	= {"NEWUNIT", " newunit =", " %v", BT_INTEGER},
+	tag_s_iqstream	= {"STREAM", " stream =", " %v", BT_CHARACTER};
+static gfc_dt *current_dt;
+#define RESOLVE_TAG(x, y) if (!resolve_tag (x, y)) return false;
+/* Are we currently processing an asynchronous I/O statement? */
+bool async_io_dt;
+/**************** Fortran 95 FORMAT parser  *****************/
+/* FORMAT tokens returned by format_lex().  */
+enum format_token
+{
+FMT_NONE, FMT_UNKNOWN, FMT_SIGNED_INT, FMT_ZERO, FMT_POSINT, FMT_PERIOD,
+FMT_COMMA, FMT_COLON, FMT_SLASH, FMT_DOLLAR, FMT_LPAREN,
+FMT_RPAREN, FMT_X, FMT_SIGN, FMT_BLANK, FMT_CHAR, FMT_P, FMT_IBOZ, FMT_F,
+FMT_E, FMT_EN, FMT_ES, FMT_G, FMT_L, FMT_A, FMT_D, FMT_H, FMT_END,
+FMT_ERROR, FMT_DC, FMT_DP, FMT_T, FMT_TR, FMT_TL, FMT_STAR, FMT_RC,
+FMT_RD, FMT_RN, FMT_RP, FMT_RU, FMT_RZ, FMT_DT
+};
+/* Local variables for checking format strings.  The saved_token is
+used to back up by a single format token during the parsing
+process.  */
+static gfc_char_t *format_string;
+static int format_string_pos;
+static int format_length, use_last_char;
+static char error_element;
+static locus format_locus;
+static format_token saved_token;
+static enum
+{ MODE_STRING, MODE_FORMAT, MODE_COPY }
+mode;
+/* Return the next character in the format string.  */
+static char
+next_char (gfc_instring in_string)
+{
+static gfc_char_t c;
+if (use_last_char)
+{
+use_last_char = 0;
+return c;
+}
+format_length++;
+if (mode == MODE_STRING)
+c = *format_string++;
+else
+{
+c = gfc_next_char_literal (in_string);
+if (c == '\n')
+	c = '\0';
+}
+if (flag_backslash && c == '\\')
+{
+locus old_locus = gfc_current_locus;
+if (gfc_match_special_char (&c) == MATCH_NO)
+	gfc_current_locus = old_locus;
+if (!(gfc_option.allow_std & GFC_STD_GNU) && !inhibit_warnings)
+	gfc_warning (0, "Extension: backslash character at %C");
+}
+if (mode == MODE_COPY)
+*format_string++ = c;
+if (mode != MODE_STRING)
+format_locus = gfc_current_locus;
+format_string_pos++;
+c = gfc_wide_toupper (c);
+return c;
+}
+/* Back up one character position.  Only works once.  */
+static void
+unget_char (void)
+{
+use_last_char = 1;
+}
+/* Eat up the spaces and return a character.  */
+static char
+next_char_not_space ()
+{
+char c;
+do
+{
+error_element = c = next_char (NONSTRING);
+if (c == '\t')
+	gfc_warning (OPT_Wtabs, "Nonconforming tab character in format at %C");
+}
+while (gfc_is_whitespace (c));
+return c;
+}
+static int value = 0;
+/* Simple lexical analyzer for getting the next token in a FORMAT
+statement.  */
+static format_token
+format_lex (void)
+{
+format_token token;
+char c, delim;
+int zflag;
+int negative_flag;
+if (saved_token != FMT_NONE)
+{
+token = saved_token;
+saved_token = FMT_NONE;
+return token;
+}
+c = next_char_not_space ();
+negative_flag = 0;
+switch (c)
+{
+case '-':
+negative_flag = 1;
+/* Falls through.  */
+case '+':
+c = next_char_not_space ();
+if (!ISDIGIT (c))
+	{
+	  token = FMT_UNKNOWN;
+	  break;
+	}
+value = c - '0';
+do
+	{
+	  c = next_char_not_space ();
+	  if (ISDIGIT (c))
+	    value = 10 * value + c - '0';
+	}
+while (ISDIGIT (c));
+unget_char ();
+if (negative_flag)
+	value = -value;
+token = FMT_SIGNED_INT;
+break;
+case '0':
+case '1':
+case '2':
+case '3':
+case '4':
+case '5':
+case '6':
+case '7':
+case '8':
+case '9':
+zflag = (c == '0');
+value = c - '0';
+do
+	{
+	  c = next_char_not_space ();
+	  if (ISDIGIT (c))
+	    {
+	      value = 10 * value + c - '0';
+	      if (c != '0')
+		zflag = 0;
+	    }
+	}
+while (ISDIGIT (c));
+unget_char ();
+token = zflag ? FMT_ZERO : FMT_POSINT;
+break;
+case '.':
+token = FMT_PERIOD;
+break;
+case ',':
+token = FMT_COMMA;
+break;
+case ':':
+token = FMT_COLON;
+break;
+case '/':
+token = FMT_SLASH;
+break;
+case '$':
+token = FMT_DOLLAR;
+break;
+case 'T':
+c = next_char_not_space ();
+switch (c)
+	{
+	case 'L':
+	  token = FMT_TL;
+	  break;
+	case 'R':
+	  token = FMT_TR;
+	  break;
+	default:
+	  token = FMT_T;
+	  unget_char ();
+	}
+break;
+case '(':
+token = FMT_LPAREN;
+break;
+case ')':
+token = FMT_RPAREN;
+break;
+case 'X':
+token = FMT_X;
+break;
+case 'S':
+c = next_char_not_space ();
+if (c != 'P' && c != 'S')
+	unget_char ();
+token = FMT_SIGN;
+break;
+case 'B':
+c = next_char_not_space ();
+if (c == 'N' || c == 'Z')
+	token = FMT_BLANK;
+else
+	{
+	  unget_char ();
+	  token = FMT_IBOZ;
+	}
+break;
+case '\'':
+case '"':
+delim = c;
+value = 0;
+for (;;)
+	{
+	  c = next_char (INSTRING_WARN);
+	  if (c == '\0')
+	    {
+	      token = FMT_END;
+	      break;
+	    }
+	  if (c == delim)
+	    {
+	      c = next_char (NONSTRING);
+	      if (c == '\0')
+		{
+		  token = FMT_END;
+		  break;
+		}
+	      if (c != delim)
+		{
+		  unget_char ();
+		  token = FMT_CHAR;
+		  break;
+		}
+	    }
+	  value++;
+	}
+break;
+case 'P':
+token = FMT_P;
+break;
+case 'I':
+case 'O':
+case 'Z':
+token = FMT_IBOZ;
+break;
+case 'F':
+token = FMT_F;
+break;
+case 'E':
+c = next_char_not_space ();
+if (c == 'N' )
+	token = FMT_EN;
+else if (c == 'S')
+token = FMT_ES;
+else
+	{
+	  token = FMT_E;
+	  unget_char ();
+	}
+break;
+case 'G':
+token = FMT_G;
+break;
+case 'H':
+token = FMT_H;
+break;
+case 'L':
+token = FMT_L;
+break;
+case 'A':
+token = FMT_A;
+break;
+case 'D':
+c = next_char_not_space ();
+if (c == 'P')
+	{
+	  if (!gfc_notify_std (GFC_STD_F2003, "DP format "
+			       "specifier not allowed at %C"))
+	    return FMT_ERROR;
+	  token = FMT_DP;
+	}
+else if (c == 'C')
+	{
+	  if (!gfc_notify_std (GFC_STD_F2003, "DC format "
+			       "specifier not allowed at %C"))
+	    return FMT_ERROR;
+	  token = FMT_DC;
+	}
+else if (c == 'T')
+	{
+	  if (!gfc_notify_std (GFC_STD_F2003, "Fortran 2003: DT format "
+	      "specifier not allowed at %C"))
+	    return FMT_ERROR;
+	  token = FMT_DT;
+	  c = next_char_not_space ();
+	  if (c == '\'' || c == '"')
+	    {
+	      delim = c;
+	      value = 0;
+	      for (;;)
+		{
+		  c = next_char (INSTRING_WARN);
+		  if (c == '\0')
+		    {
+		      token = FMT_END;
+		      break;
+		    }
+		  if (c == delim)
+		    {
+		      c = next_char (NONSTRING);
+		      if (c == '\0')
+			{
+			  token = FMT_END;
+			  break;
+			}
+		      if (c == '/')
+			{
+			  token = FMT_SLASH;
+			  break;
+			}
+		      if (c == delim)
+			continue;
+		      unget_char ();
+		      break;
+		    }
+		}
+	    }
+	  else if (c == '/')
+	    {
+	      token = FMT_SLASH;
+	      break;
+	    }
+	  else
+	    unget_char ();
+	}
+else
+	{
+	  token = FMT_D;
+	  unget_char ();
+	}
+break;
+case 'R':
+c = next_char_not_space ();
+switch (c)
+	{
+	case 'C':
+	  token = FMT_RC;
+	  break;
+	case 'D':
+	  token = FMT_RD;
+	  break;
+	case 'N':
+	  token = FMT_RN;
+	  break;
+	case 'P':
+	  token = FMT_RP;
+	  break;
+	case 'U':
+	  token = FMT_RU;
+	  break;
+	case 'Z':
+	  token = FMT_RZ;
+	  break;
+	default:
+	  token = FMT_UNKNOWN;
+	  unget_char ();
+	  break;
+	}
+break;
+case '\0':
+token = FMT_END;
+break;
+case '*':
+token = FMT_STAR;
+break;
+default:
+token = FMT_UNKNOWN;
+break;
+}
+return token;
+}
+static const char *
+token_to_string (format_token t)
+{
+switch (t)
+{
+case FMT_D:
+	return "D";
+case FMT_G:
+	return "G";
+case FMT_E:
+	return "E";
+case FMT_EN:
+	return "EN";
+case FMT_ES:
+	return "ES";
+default:
+return "";
+}
+}
+/* Check a format statement.  The format string, either from a FORMAT
+statement or a constant in an I/O statement has already been parsed
+by itself, and we are checking it for validity.  The dual origin
+means that the warning message is a little less than great.  */
+static bool
+check_format (bool is_input)
+{
+const char *posint_required	  = _("Positive width required");
+const char *nonneg_required	  = _("Nonnegative width required");
+const char *unexpected_element  = _("Unexpected element %qc in format "
+				      "string at %L");
+const char *unexpected_end	  = _("Unexpected end of format string");
+const char *zero_width	  = _("Zero width in format descriptor");
+const char *error = NULL;
+format_token t, u;
+int level;
+int repeat;
+bool rv;
+use_last_char = 0;
+saved_token = FMT_NONE;
+level = 0;
+repeat = 0;
+rv = true;
+format_string_pos = 0;
+t = format_lex ();
+if (t == FMT_ERROR)
+goto fail;
+if (t != FMT_LPAREN)
+{
+error = _("Missing leading left parenthesis");
+goto syntax;
+}
+t = format_lex ();
+if (t == FMT_ERROR)
+goto fail;
+if (t == FMT_RPAREN)
+goto finished;		/* Empty format is legal */
+saved_token = t;
+format_item:
+/* In this state, the next thing has to be a format item.  */
+t = format_lex ();
+if (t == FMT_ERROR)
+goto fail;
+format_item_1:
+switch (t)
+{
+case FMT_STAR:
+repeat = -1;
+t = format_lex ();
+if (t == FMT_ERROR)
+	goto fail;
+if (t == FMT_LPAREN)
+	{
+	  level++;
+	  goto format_item;
+	}
+error = _("Left parenthesis required after %<*%>");
+goto syntax;
+case FMT_POSINT:
+repeat = value;
+t = format_lex ();
+if (t == FMT_ERROR)
+	goto fail;
+if (t == FMT_LPAREN)
+	{
+	  level++;
+	  goto format_item;
+	}
+if (t == FMT_SLASH)
+	goto optional_comma;
+goto data_desc;
+case FMT_LPAREN:
+level++;
+goto format_item;
+case FMT_SIGNED_INT:
+case FMT_ZERO:
+/* Signed integer can only precede a P format.  */
+t = format_lex ();
+if (t == FMT_ERROR)
+	goto fail;
+if (t != FMT_P)
+	{
+	  error = _("Expected P edit descriptor");
+	  goto syntax;
+	}
+goto data_desc;
+case FMT_P:
+/* P requires a prior number.  */
+error = _("P descriptor requires leading scale factor");
+goto syntax;
+case FMT_X:
+/* X requires a prior number if we're being pedantic.  */
+if (mode != MODE_FORMAT)
+	format_locus.nextc += format_string_pos;
+if (!gfc_notify_std (GFC_STD_GNU, "X descriptor requires leading "
+			   "space count at %L", &format_locus))
+	return false;
+goto between_desc;
+case FMT_SIGN:
+case FMT_BLANK:
+case FMT_DP:
+case FMT_DC:
+case FMT_RC:
+case FMT_RD:
+case FMT_RN:
+case FMT_RP:
+case FMT_RU:
+case FMT_RZ:
+goto between_desc;
+case FMT_CHAR:
+goto extension_optional_comma;
+case FMT_COLON:
+case FMT_SLASH:
+goto optional_comma;
+case FMT_DOLLAR:
+t = format_lex ();
+if (t == FMT_ERROR)
+	goto fail;
+if (!gfc_notify_std (GFC_STD_GNU, "$ descriptor at %L", &format_locus))
+	return false;
+if (t != FMT_RPAREN || level > 0)
+	{
+	  gfc_warning (0, "$ should be the last specifier in format at %L",
+		       &format_locus);
+	  goto optional_comma_1;
+	}
+goto finished;
+case FMT_T:
+case FMT_TL:
+case FMT_TR:
+case FMT_IBOZ:
+case FMT_F:
+case FMT_E:
+case FMT_EN:
+case FMT_ES:
+case FMT_G:
+case FMT_L:
+case FMT_A:
+case FMT_D:
+case FMT_H:
+case FMT_DT:
+goto data_desc;
+case FMT_END:
+error = unexpected_end;
+goto syntax;
+default:
+error = unexpected_element;
+goto syntax;
+}
+data_desc:
+/* In this state, t must currently be a data descriptor.
+Deal with things that can/must follow the descriptor.  */
+switch (t)
+{
+case FMT_SIGN:
+case FMT_BLANK:
+case FMT_DP:
+case FMT_DC:
+case FMT_X:
+break;
+case FMT_P:
+/* No comma after P allowed only for F, E, EN, ES, D, or G.
+	 10.1.1 (1).  */
+t = format_lex ();
+if (t == FMT_ERROR)
+	goto fail;
+if (!(gfc_option.allow_std & GFC_STD_F2003) && t != FMT_COMMA
+	  && t != FMT_F && t != FMT_E && t != FMT_EN && t != FMT_ES
+	  && t != FMT_D && t != FMT_G && t != FMT_RPAREN && t != FMT_SLASH)
+	{
+	  error = _("Comma required after P descriptor");
+	  goto syntax;
+	}
+if (t != FMT_COMMA)
+	{
+	  if (t == FMT_POSINT)
+	    {
+	      t = format_lex ();
+	      if (t == FMT_ERROR)
+		goto fail;
+	    }
+if (t != FMT_F && t != FMT_E && t != FMT_EN && t != FMT_ES && t != FMT_D
+	      && t != FMT_G && t != FMT_RPAREN && t != FMT_SLASH)
+	    {
+	      error = _("Comma required after P descriptor");
+	      goto syntax;
+	    }
+	}
+saved_token = t;
+goto optional_comma;
+case FMT_T:
+case FMT_TL:
+case FMT_TR:
+t = format_lex ();
+if (t != FMT_POSINT)
+	{
+	  error = _("Positive width required with T descriptor");
+	  goto syntax;
+	}
+break;
+case FMT_L:
+t = format_lex ();
+if (t == FMT_ERROR)
+	goto fail;
+if (t == FMT_POSINT)
+	break;
+if (mode != MODE_FORMAT)
+	format_locus.nextc += format_string_pos;
+if (t == FMT_ZERO)
+	{
+	  switch (gfc_notification_std (GFC_STD_GNU))
+	    {
+	      case WARNING:
+		gfc_warning (0, "Extension: Zero width after L "
+			     "descriptor at %L", &format_locus);
+		break;
+	      case ERROR:
+		gfc_error ("Extension: Zero width after L "
+			     "descriptor at %L", &format_locus);
+		goto fail;
+	      case SILENT:
+		break;
+	      default:
+		gcc_unreachable ();
+	    }
+	}
+else
+	{
+	  saved_token = t;
+	  gfc_notify_std (GFC_STD_GNU, "Missing positive width after "
+			  "L descriptor at %L", &format_locus);
+	}
+break;
+case FMT_A:
+t = format_lex ();
+if (t == FMT_ERROR)
+	goto fail;
+if (t == FMT_ZERO)
+	{
+	  error = zero_width;
+	  goto syntax;
+	}
+if (t != FMT_POSINT)
+	saved_token = t;
+break;
+case FMT_D:
+case FMT_E:
+case FMT_G:
+case FMT_EN:
+case FMT_ES:
+u = format_lex ();
+if (t == FMT_G && u == FMT_ZERO)
+	{
+	  if (is_input)
+	    {
+	      error = zero_width;
+	      goto syntax;
+	    }
+	  if (!gfc_notify_std (GFC_STD_F2008, "%<G0%> in format at %L",
+			       &format_locus))
+	    return false;
+	  u = format_lex ();
+	  if (u != FMT_PERIOD)
+	    {
+	      saved_token = u;
+	      break;
+	    }
+	  u = format_lex ();
+	  if (u != FMT_POSINT)
+	    {
+	      error = posint_required;
+	      goto syntax;
+	    }
+	  u = format_lex ();
+	  if (u == FMT_E)
+	    {
+	      error = _("E specifier not allowed with g0 descriptor");
+	      goto syntax;
+	    }
+	  saved_token = u;
+	  break;
+	}
+if (u != FMT_POSINT)
+	{
+	  format_locus.nextc += format_string_pos;
+	  gfc_error ("Positive width required in format "
+			 "specifier %s at %L", token_to_string (t),
+			 &format_locus);
+	  saved_token = u;
+	  goto fail;
+	}
+u = format_lex ();
+if (u == FMT_ERROR)
+	goto fail;
+if (u != FMT_PERIOD)
+	{
+	  /* Warn if -std=legacy, otherwise error.  */
+	  format_locus.nextc += format_string_pos;
+	  if (gfc_option.warn_std != 0)
+	    {
+	      gfc_error ("Period required in format "
+			     "specifier %s at %L", token_to_string (t),
+			     &format_locus);
+	      saved_token = u;
+goto fail;
+	    }
+	  else
+	    gfc_warning (0, "Period required in format "
+			 "specifier %s at %L", token_to_string (t),
+			  &format_locus);
+	  /* If we go to finished, we need to unwind this
+	     before the next round.  */
+	  format_locus.nextc -= format_string_pos;
+	  saved_token = u;
+	  break;
+	}
+u = format_lex ();
+if (u == FMT_ERROR)
+	goto fail;
+if (u != FMT_ZERO && u != FMT_POSINT)
+	{
+	  error = nonneg_required;
+	  goto syntax;
+	}
+if (t == FMT_D)
+	break;
+/* Look for optional exponent.  */
+u = format_lex ();
+if (u == FMT_ERROR)
+	goto fail;
+if (u != FMT_E)
+	{
+	  saved_token = u;
+	}
+else
+	{
+	  u = format_lex ();
+	  if (u == FMT_ERROR)
+	    goto fail;
+	  if (u != FMT_POSINT)
+	    {
+	      error = _("Positive exponent width required");
+	      goto syntax;
+	    }
+	}
+break;
+case FMT_DT:
+t = format_lex ();
+if (t == FMT_ERROR)
+	goto fail;
+switch (t)
+	{
+	case FMT_RPAREN:
+	  level--;
+	  if (level < 0)
+	    goto finished;
+	  goto between_desc;
+	case FMT_COMMA:
+	  goto format_item;
+	case FMT_LPAREN:
+dtio_vlist:
+	  t = format_lex ();
+	  if (t == FMT_ERROR)
+	    goto fail;
+	  if (t != FMT_POSINT)
+	    {
+	      error = posint_required;
+	      goto syntax;
+	    }
+	  t = format_lex ();
+	  if (t == FMT_ERROR)
+	    goto fail;
+	  if (t == FMT_COMMA)
+	    goto dtio_vlist;
+	  if (t != FMT_RPAREN)
+	    {
+	      error = _("Right parenthesis expected at %C");
+	      goto syntax;
+	    }
+	  goto between_desc;
+	default:
+	  error = unexpected_element;
+	  goto syntax;
+	}
+break;
+case FMT_F:
+t = format_lex ();
+if (t == FMT_ERROR)
+	goto fail;
+if (t != FMT_ZERO && t != FMT_POSINT)
+	{
+	  error = nonneg_required;
+	  goto syntax;
+	}
+else if (is_input && t == FMT_ZERO)
+	{
+	  error = posint_required;
+	  goto syntax;
+	}
+t = format_lex ();
+if (t == FMT_ERROR)
+	goto fail;
+if (t != FMT_PERIOD)
+	{
+	  /* Warn if -std=legacy, otherwise error.  */
+	  if (gfc_option.warn_std != 0)
+	    {
+	      error = _("Period required in format specifier");
+	      goto syntax;
+	    }
+	  if (mode != MODE_FORMAT)
+	    format_locus.nextc += format_string_pos;
+	  gfc_warning (0, "Period required in format specifier at %L",
+		       &format_locus);
+	  saved_token = t;
+	  break;
+	}
+t = format_lex ();
+if (t == FMT_ERROR)
+	goto fail;
+if (t != FMT_ZERO && t != FMT_POSINT)
+	{
+	  error = nonneg_required;
+	  goto syntax;
+	}
+break;
+case FMT_H:
+if (!(gfc_option.allow_std & GFC_STD_GNU) && !inhibit_warnings)
+	{
+	  if (mode != MODE_FORMAT)
+	    format_locus.nextc += format_string_pos;
+	  gfc_warning (0, "The H format specifier at %L is"
+		       " a Fortran 95 deleted feature", &format_locus);
+	}
+if (mode == MODE_STRING)
+	{
+	  format_string += value;
+	  format_length -= value;
+format_string_pos += repeat;
+	}
+else
+	{
+	  while (repeat >0)
+	   {
+	     next_char (INSTRING_WARN);
+	     repeat -- ;
+	   }
+	}
+break;
+case FMT_IBOZ:
+t = format_lex ();
+if (t == FMT_ERROR)
+	goto fail;
+if (t != FMT_ZERO && t != FMT_POSINT)
+	{
+	  error = nonneg_required;
+	  goto syntax;
+	}
+else if (is_input && t == FMT_ZERO)
+	{
+	  error = posint_required;
+	  goto syntax;
+	}
+t = format_lex ();
+if (t == FMT_ERROR)
+	goto fail;
+if (t != FMT_PERIOD)
+	{
+	  saved_token = t;
+	}
+else
+	{
+	  t = format_lex ();
+	  if (t == FMT_ERROR)
+	    goto fail;
+	  if (t != FMT_ZERO && t != FMT_POSINT)
+	    {
+	      error = nonneg_required;
+	      goto syntax;
+	    }
+	}
+break;
+default:
+error = unexpected_element;
+goto syntax;
+}
+between_desc:
+/* Between a descriptor and what comes next.  */
+t = format_lex ();
+if (t == FMT_ERROR)
+goto fail;
+switch (t)
+{
+case FMT_COMMA:
+goto format_item;
+case FMT_RPAREN:
+level--;
+if (level < 0)
+	goto finished;
+goto between_desc;
+case FMT_COLON:
+case FMT_SLASH:
+goto optional_comma;
+case FMT_END:
+error = unexpected_end;
+goto syntax;
+default:
+if (mode != MODE_FORMAT)
+	format_locus.nextc += format_string_pos - 1;
+if (!gfc_notify_std (GFC_STD_GNU, "Missing comma at %L", &format_locus))
+	return false;
+/* If we do not actually return a failure, we need to unwind this
+before the next round.  */
+if (mode != MODE_FORMAT)
+	format_locus.nextc -= format_string_pos;
+goto format_item_1;
+}
+optional_comma:
+/* Optional comma is a weird between state where we've just finished
+reading a colon, slash, dollar or P descriptor.  */
+t = format_lex ();
+if (t == FMT_ERROR)
+goto fail;
+optional_comma_1:
+switch (t)
+{
+case FMT_COMMA:
+break;
+case FMT_RPAREN:
+level--;
+if (level < 0)
+	goto finished;
+goto between_desc;
+default:
+/* Assume that we have another format item.  */
+saved_token = t;
+break;
+}
+goto format_item;
+extension_optional_comma:
+/* As a GNU extension, permit a missing comma after a string literal.  */
+t = format_lex ();
+if (t == FMT_ERROR)
+goto fail;
+switch (t)
+{
+case FMT_COMMA:
+break;
+case FMT_RPAREN:
+level--;
+if (level < 0)
+	goto finished;
+goto between_desc;
+case FMT_COLON:
+case FMT_SLASH:
+goto optional_comma;
+case FMT_END:
+error = unexpected_end;
+goto syntax;
+default:
+if (mode != MODE_FORMAT)
+	format_locus.nextc += format_string_pos;
+if (!gfc_notify_std (GFC_STD_GNU, "Missing comma at %L", &format_locus))
+	return false;
+/* If we do not actually return a failure, we need to unwind this
+before the next round.  */
+if (mode != MODE_FORMAT)
+	format_locus.nextc -= format_string_pos;
+saved_token = t;
+break;
+}
+goto format_item;
+syntax:
+if (mode != MODE_FORMAT)
+format_locus.nextc += format_string_pos;
+if (error == unexpected_element)
+gfc_error (error, error_element, &format_locus);
+else
+gfc_error ("%s in format string at %L", error, &format_locus);
+fail:
+rv = false;
+finished:
+return rv;
+}
+/* Given an expression node that is a constant string, see if it looks
+like a format string.  */
+static bool
+check_format_string (gfc_expr *e, bool is_input)
+{
+bool rv;
+int i;
+if (!e || e->ts.type != BT_CHARACTER || e->expr_type != EXPR_CONSTANT)
+return true;
+mode = MODE_STRING;
+format_string = e->value.character.string;
+/* More elaborate measures are needed to show where a problem is within a
+format string that has been calculated, but that's probably not worth the
+effort.  */
+format_locus = e->where;
+rv = check_format (is_input);
+/* check for extraneous characters at the end of an otherwise valid format
+string, like '(A10,I3)F5'
+start at the end and move back to the last character processed,
+spaces are OK */
+if (rv && e->value.character.length > format_string_pos)
+for (i=e->value.character.length-1;i>format_string_pos-1;i--)
+if (e->value.character.string[i] != ' ')
+{
+format_locus.nextc += format_length + 1;
+gfc_warning (0,
+		       "Extraneous characters in format at %L", &format_locus);
+break;
+}
+return rv;
+}
+/************ Fortran I/O statement matchers *************/
+/* Match a FORMAT statement.  This amounts to actually parsing the
+format descriptors in order to correctly locate the end of the
+format string.  */
+match
+gfc_match_format (void)
+{
+gfc_expr *e;
+locus start;
+if (gfc_current_ns->proc_name
+&& gfc_current_ns->proc_name->attr.flavor == FL_MODULE)
+{
+gfc_error ("Format statement in module main block at %C");
+return MATCH_ERROR;
+}
+/* Before parsing the rest of a FORMAT statement, check F2008:c1206.  */
+if ((gfc_current_state () == COMP_FUNCTION
+|| gfc_current_state () == COMP_SUBROUTINE)
+&& gfc_state_stack->previous->state == COMP_INTERFACE)
+{
+gfc_error ("FORMAT statement at %C cannot appear within an INTERFACE");
+return MATCH_ERROR;
+}
+if (gfc_statement_label == NULL)
+{
+gfc_error ("Missing format label at %C");
+return MATCH_ERROR;
+}
+gfc_gobble_whitespace ();
+mode = MODE_FORMAT;
+format_length = 0;
+start = gfc_current_locus;
+if (!check_format (false))
+return MATCH_ERROR;
+if (gfc_match_eos () != MATCH_YES)
+{
+gfc_syntax_error (ST_FORMAT);
+return MATCH_ERROR;
+}
+/* The label doesn't get created until after the statement is done
+being matched, so we have to leave the string for later.  */
+gfc_current_locus = start;	/* Back to the beginning */
+new_st.loc = start;
+new_st.op = EXEC_NOP;
+e = gfc_get_character_expr (gfc_default_character_kind, &start,
+			      NULL, format_length);
+format_string = e->value.character.string;
+gfc_statement_label->format = e;
+mode = MODE_COPY;
+check_format (false);		/* Guaranteed to succeed */
+gfc_match_eos ();		/* Guaranteed to succeed */
+return MATCH_YES;
+}
+/* Check for a CHARACTER variable.  The check for scalar is done in
+resolve_tag.  */
+static bool
+check_char_variable (gfc_expr *e)
+{
+if (e->expr_type != EXPR_VARIABLE || e->ts.type != BT_CHARACTER)
+{
+gfc_error("IOMSG must be a scalar-default-char-variable at %L", &e->where);
+return false;
+}
+return true;
+}
+static bool
+is_char_type (const char *name, gfc_expr *e)
+{
+gfc_resolve_expr (e);
+if (e->ts.type != BT_CHARACTER)
+{
+gfc_error ("%s requires a scalar-default-char-expr at %L",
+		   name, &e->where);
+return false;
+}
+return true;
+}
+/* Match an expression I/O tag of some sort.  */
+static match
+match_etag (const io_tag *tag, gfc_expr **v)
+{
+gfc_expr *result;
+match m;
+m = gfc_match (tag->spec);
+if (m != MATCH_YES)
+return m;
+m = gfc_match (tag->value, &result);
+if (m != MATCH_YES)
+{
+gfc_error ("Invalid value for %s specification at %C", tag->name);
+return MATCH_ERROR;
+}
+if (*v != NULL)
+{
+gfc_error ("Duplicate %s specification at %C", tag->name);
+gfc_free_expr (result);
+return MATCH_ERROR;
+}
+*v = result;
+return MATCH_YES;
+}
+/* Match a variable I/O tag of some sort.  */
+static match
+match_vtag (const io_tag *tag, gfc_expr **v)
+{
+gfc_expr *result;
+match m;
+m = gfc_match (tag->spec);
+if (m != MATCH_YES)
+return m;
+m = gfc_match (tag->value, &result);
+if (m != MATCH_YES)
+{
+gfc_error ("Invalid value for %s specification at %C", tag->name);
+return MATCH_ERROR;
+}
+if (*v != NULL)
+{
+gfc_error ("Duplicate %s specification at %C", tag->name);
+gfc_free_expr (result);
+return MATCH_ERROR;
+}
+if (result->symtree->n.sym->attr.intent == INTENT_IN)
+{
+gfc_error ("Variable %s cannot be INTENT(IN) at %C", tag->name);
+gfc_free_expr (result);
+return MATCH_ERROR;
+}
+bool impure = gfc_impure_variable (result->symtree->n.sym);
+if (impure && gfc_pure (NULL))
+{
+gfc_error ("Variable %s cannot be assigned in PURE procedure at %C",
+		 tag->name);
+gfc_free_expr (result);
+return MATCH_ERROR;
+}
+if (impure)
+gfc_unset_implicit_pure (NULL);
+*v = result;
+return MATCH_YES;
+}
+/* Match I/O tags that cause variables to become redefined.  */
+static match
+match_out_tag (const io_tag *tag, gfc_expr **result)
+{
+match m;
+m = match_vtag (tag, result);
+if (m == MATCH_YES)
+gfc_check_do_variable ((*result)->symtree);
+return m;
+}
+/* Match a label I/O tag.  */
+static match
+match_ltag (const io_tag *tag, gfc_st_label ** label)
+{
+match m;
+gfc_st_label *old;
+old = *label;
+m = gfc_match (tag->spec);
+if (m != MATCH_YES)
+return m;
+m = gfc_match (tag->value, label);
+if (m != MATCH_YES)
+{
+gfc_error ("Invalid value for %s specification at %C", tag->name);
+return MATCH_ERROR;
+}
+if (old)
+{
+gfc_error ("Duplicate %s label specification at %C", tag->name);
+return MATCH_ERROR;
+}
+if (!gfc_reference_st_label (*label, ST_LABEL_TARGET))
+return MATCH_ERROR;
+return m;
+}
+/* Match a tag using match_etag, but only if -fdec is enabled.  */
+static match
+match_dec_etag (const io_tag *tag, gfc_expr **e)
+{
+match m = match_etag (tag, e);
+if (flag_dec && m != MATCH_NO)
+return m;
+else if (m != MATCH_NO)
+{
+gfc_error ("%s at %C is a DEC extension, enable with "
+		 "%<-fdec%>", tag->name);
+return MATCH_ERROR;
+}
+return m;
+}
+/* Match a tag using match_vtag, but only if -fdec is enabled.  */
+static match
+match_dec_vtag (const io_tag *tag, gfc_expr **e)
+{
+match m = match_vtag(tag, e);
+if (flag_dec && m != MATCH_NO)
+return m;
+else if (m != MATCH_NO)
+{
+gfc_error ("%s at %C is a DEC extension, enable with "
+		 "%<-fdec%>", tag->name);
+return MATCH_ERROR;
+}
+return m;
+}
+/* Match a DEC I/O flag tag - a tag with no expression such as READONLY.  */
+static match
+match_dec_ftag (const io_tag *tag, gfc_open *o)
+{
+match m;
+m = gfc_match (tag->spec);
+if (m != MATCH_YES)
+return m;
+if (!flag_dec)
+{
+gfc_error ("%s at %C is a DEC extension, enable with "
+		 "%<-fdec%>", tag->name);
+return MATCH_ERROR;
+}
+/* Just set the READONLY flag, which we use at runtime to avoid delete on
+close.  */
+if (tag == &tag_readonly)
+{
+o->readonly |= 1;
+return MATCH_YES;
+}
+/* Interpret SHARED as SHARE='DENYNONE' (read lock).  */
+else if (tag == &tag_shared)
+{
+if (o->share != NULL)
+	{
+	  gfc_error ("Duplicate %s specification at %C", tag->name);
+	  return MATCH_ERROR;
+	}
+o->share = gfc_get_character_expr (gfc_default_character_kind,
+	  &gfc_current_locus, "denynone", 8);
+return MATCH_YES;
+}
+/* Interpret NOSHARED as SHARE='DENYRW' (exclusive lock).  */
+else if (tag == &tag_noshared)
+{
+if (o->share != NULL)
+	{
+	  gfc_error ("Duplicate %s specification at %C", tag->name);
+	  return MATCH_ERROR;
+	}
+o->share = gfc_get_character_expr (gfc_default_character_kind,
+	  &gfc_current_locus, "denyrw", 6);
+return MATCH_YES;
+}
+/* We handle all DEC tags above.  */
+gcc_unreachable ();
+}
+/* Resolution of the FORMAT tag, to be called from resolve_tag.  */
+static bool
+resolve_tag_format (const gfc_expr *e)
+{
+if (e->expr_type == EXPR_CONSTANT
+&& (e->ts.type != BT_CHARACTER
+	  || e->ts.kind != gfc_default_character_kind))
+{
+gfc_error ("Constant expression in FORMAT tag at %L must be "
+		 "of type default CHARACTER", &e->where);
+return false;
+}
+/* If e's rank is zero and e is not an element of an array, it should be
+of integer or character type.  The integer variable should be
+ASSIGNED.  */
+if (e->rank == 0
+&& (e->expr_type != EXPR_VARIABLE
+	  || e->symtree == NULL
+	  || e->symtree->n.sym->as == NULL
+	  || e->symtree->n.sym->as->rank == 0))
+{
+if ((e->ts.type != BT_CHARACTER
+	   || e->ts.kind != gfc_default_character_kind)
+	  && e->ts.type != BT_INTEGER)
+	{
+	  gfc_error ("FORMAT tag at %L must be of type default-kind CHARACTER "
+		     "or of INTEGER", &e->where);
+	  return false;
+	}
+else if (e->ts.type == BT_INTEGER && e->expr_type == EXPR_VARIABLE)
+	{
+	  if (!gfc_notify_std (GFC_STD_F95_DEL, "ASSIGNED variable in "
+			       "FORMAT tag at %L", &e->where))
+	    return false;
+	  if (e->symtree->n.sym->attr.assign != 1)
+	    {
+	      gfc_error ("Variable %qs at %L has not been assigned a "
+			 "format label", e->symtree->n.sym->name, &e->where);
+	      return false;
+	    }
+	}
+else if (e->ts.type == BT_INTEGER)
+	{
+	  gfc_error ("Scalar %qs in FORMAT tag at %L is not an ASSIGNED "
+		     "variable", gfc_basic_typename (e->ts.type), &e->where);
+	  return false;
+	}
+return true;
+}
+/* If rank is nonzero and type is not character, we allow it under GFC_STD_LEGACY.
+It may be assigned an Hollerith constant.  */
+if (e->ts.type != BT_CHARACTER)
+{
+if (!gfc_notify_std (GFC_STD_LEGACY, "Non-character in FORMAT tag "
+			   "at %L", &e->where))
+	return false;
+if (e->rank == 0 && e->symtree->n.sym->as->type == AS_ASSUMED_SHAPE)
+	{
+	  gfc_error ("Non-character assumed shape array element in FORMAT"
+		     " tag at %L", &e->where);
+	  return false;
+	}
+if (e->rank == 0 && e->symtree->n.sym->as->type == AS_ASSUMED_SIZE)
+	{
+	  gfc_error ("Non-character assumed size array element in FORMAT"
+		     " tag at %L", &e->where);
+	  return false;
+	}
+if (e->rank == 0 && e->symtree->n.sym->attr.pointer)
+	{
+	  gfc_error ("Non-character pointer array element in FORMAT tag at %L",
+		     &e->where);
+	  return false;
+	}
+}
+return true;
+}
+/* Do expression resolution and type-checking on an expression tag.  */
+static bool
+resolve_tag (const io_tag *tag, gfc_expr *e)
+{
+if (e == NULL)
+return true;
+if (!gfc_resolve_expr (e))
+return false;
+if (tag == &tag_format)
+return resolve_tag_format (e);
+if (e->ts.type != tag->type)
+{
+gfc_error ("%s tag at %L must be of type %s", tag->name,
+		 &e->where, gfc_basic_typename (tag->type));
+return false;
+}
+if (e->ts.type == BT_CHARACTER && e->ts.kind != gfc_default_character_kind)
+{
+gfc_error ("%s tag at %L must be a character string of default kind",
+		 tag->name, &e->where);
+return false;
+}
+if (e->rank != 0)
+{
+gfc_error ("%s tag at %L must be scalar", tag->name, &e->where);
+return false;
+}
+if (tag == &tag_iomsg)
+{
+if (!gfc_notify_std (GFC_STD_F2003, "IOMSG tag at %L", &e->where))
+	return false;
+}
+if ((tag == &tag_iostat || tag == &tag_size || tag == &tag_iolength
+|| tag == &tag_number || tag == &tag_nextrec || tag == &tag_s_recl)
+&& e->ts.kind != gfc_default_integer_kind)
+{
+if (!gfc_notify_std (GFC_STD_F2003, "Fortran 95 requires default "
+			   "INTEGER in %s tag at %L", tag->name, &e->where))
+	return false;
+}
+if (e->ts.kind != gfc_default_logical_kind &&
+(tag == &tag_exist || tag == &tag_named || tag == &tag_opened
+|| tag == &tag_pending))
+{
+if (!gfc_notify_std (GFC_STD_F2008, "Non-default LOGICAL kind "
+			   "in %s tag at %L", tag->name, &e->where))
+	return false;
+}
+if (tag == &tag_newunit)
+{
+if (!gfc_notify_std (GFC_STD_F2008, "NEWUNIT specifier at %L",
+			   &e->where))
+	return false;
+}
+/* NEWUNIT, IOSTAT, SIZE and IOMSG are variable definition contexts.  */
+if (tag == &tag_newunit || tag == &tag_iostat
+|| tag == &tag_size || tag == &tag_iomsg)
+{
+char context[64];
+sprintf (context, _("%s tag"), tag->name);
+if (!gfc_check_vardef_context (e, false, false, false, context))
+	return false;
+}
+if (tag == &tag_convert)
+{
+if (!gfc_notify_std (GFC_STD_GNU, "CONVERT tag at %L", &e->where))
+	return false;
+}
+return true;
+}
+/* Match a single tag of an OPEN statement.  */
+static match
+match_open_element (gfc_open *open)
+{
+match m;
+m = match_etag (&tag_e_async, &open->asynchronous);
+if (m == MATCH_YES && !is_char_type ("ASYNCHRONOUS", open->asynchronous))
+return MATCH_ERROR;
+if (m != MATCH_NO)
+return m;
+m = match_etag (&tag_unit, &open->unit);
+if (m != MATCH_NO)
+return m;
+m = match_etag (&tag_iomsg, &open->iomsg);
+if (m == MATCH_YES && !check_char_variable (open->iomsg))
+return MATCH_ERROR;
+if (m != MATCH_NO)
+return m;
+m = match_out_tag (&tag_iostat, &open->iostat);
+if (m != MATCH_NO)
+return m;
+m = match_etag (&tag_file, &open->file);
+if (m != MATCH_NO)
+return m;
+m = match_etag (&tag_status, &open->status);
+if (m != MATCH_NO)
+return m;
+m = match_etag (&tag_e_access, &open->access);
+if (m != MATCH_NO)
+return m;
+m = match_etag (&tag_e_form, &open->form);
+if (m != MATCH_NO)
+return m;
+m = match_etag (&tag_e_recl, &open->recl);
+if (m != MATCH_NO)
+return m;
+m = match_etag (&tag_e_blank, &open->blank);
+if (m != MATCH_NO)
+return m;
+m = match_etag (&tag_e_position, &open->position);
+if (m != MATCH_NO)
+return m;
+m = match_etag (&tag_e_action, &open->action);
+if (m != MATCH_NO)
+return m;
+m = match_etag (&tag_e_delim, &open->delim);
+if (m != MATCH_NO)
+return m;
+m = match_etag (&tag_e_pad, &open->pad);
+if (m != MATCH_NO)
+return m;
+m = match_etag (&tag_e_decimal, &open->decimal);
+if (m != MATCH_NO)
+return m;
+m = match_etag (&tag_e_encoding, &open->encoding);
+if (m != MATCH_NO)
+return m;
+m = match_etag (&tag_e_round, &open->round);
+if (m != MATCH_NO)
+return m;
+m = match_etag (&tag_e_sign, &open->sign);
+if (m != MATCH_NO)
+return m;
+m = match_ltag (&tag_err, &open->err);
+if (m != MATCH_NO)
+return m;
+m = match_etag (&tag_convert, &open->convert);
+if (m != MATCH_NO)
+return m;
+m = match_out_tag (&tag_newunit, &open->newunit);
+if (m != MATCH_NO)
+return m;
+/* The following are extensions enabled with -fdec.  */
+m = match_dec_etag (&tag_e_share, &open->share);
+if (m != MATCH_NO)
+return m;
+m = match_dec_etag (&tag_cc, &open->cc);
+if (m != MATCH_NO)
+return m;
+m = match_dec_ftag (&tag_readonly, open);
+if (m != MATCH_NO)
+return m;
+m = match_dec_ftag (&tag_shared, open);
+if (m != MATCH_NO)
+return m;
+m = match_dec_ftag (&tag_noshared, open);
+if (m != MATCH_NO)
+return m;
+return MATCH_NO;
+}
+/* Free the gfc_open structure and all the expressions it contains.  */
+void
+gfc_free_open (gfc_open *open)
+{
+if (open == NULL)
+return;
+gfc_free_expr (open->unit);
+gfc_free_expr (open->iomsg);
+gfc_free_expr (open->iostat);
+gfc_free_expr (open->file);
+gfc_free_expr (open->status);
+gfc_free_expr (open->access);
+gfc_free_expr (open->form);
+gfc_free_expr (open->recl);
+gfc_free_expr (open->blank);
+gfc_free_expr (open->position);
+gfc_free_expr (open->action);
+gfc_free_expr (open->delim);
+gfc_free_expr (open->pad);
+gfc_free_expr (open->decimal);
+gfc_free_expr (open->encoding);
+gfc_free_expr (open->round);
+gfc_free_expr (open->sign);
+gfc_free_expr (open->convert);
+gfc_free_expr (open->asynchronous);
+gfc_free_expr (open->newunit);
+gfc_free_expr (open->share);
+gfc_free_expr (open->cc);
+free (open);
+}
+/* Resolve everything in a gfc_open structure.  */
+bool
+gfc_resolve_open (gfc_open *open)
+{
+RESOLVE_TAG (&tag_unit, open->unit);
+RESOLVE_TAG (&tag_iomsg, open->iomsg);
+RESOLVE_TAG (&tag_iostat, open->iostat);
+RESOLVE_TAG (&tag_file, open->file);
+RESOLVE_TAG (&tag_status, open->status);
+RESOLVE_TAG (&tag_e_access, open->access);
+RESOLVE_TAG (&tag_e_form, open->form);
+RESOLVE_TAG (&tag_e_recl, open->recl);
+RESOLVE_TAG (&tag_e_blank, open->blank);
+RESOLVE_TAG (&tag_e_position, open->position);
+RESOLVE_TAG (&tag_e_action, open->action);
+RESOLVE_TAG (&tag_e_delim, open->delim);
+RESOLVE_TAG (&tag_e_pad, open->pad);
+RESOLVE_TAG (&tag_e_decimal, open->decimal);
+RESOLVE_TAG (&tag_e_encoding, open->encoding);
+RESOLVE_TAG (&tag_e_async, open->asynchronous);
+RESOLVE_TAG (&tag_e_round, open->round);
+RESOLVE_TAG (&tag_e_sign, open->sign);
+RESOLVE_TAG (&tag_convert, open->convert);
+RESOLVE_TAG (&tag_newunit, open->newunit);
+RESOLVE_TAG (&tag_e_share, open->share);
+RESOLVE_TAG (&tag_cc, open->cc);
+if (!gfc_reference_st_label (open->err, ST_LABEL_TARGET))
+return false;
+return true;
+}
+/* Check if a given value for a SPECIFIER is either in the list of values
+allowed in F95 or F2003, issuing an error message and returning a zero
+value if it is not allowed.  */
+static int
+compare_to_allowed_values (const char *specifier, const char *allowed[],
+			   const char *allowed_f2003[],
+			   const char *allowed_gnu[], gfc_char_t *value,
+			   const char *statement, bool warn,
+			   int *num = NULL);
+static int
+compare_to_allowed_values (const char *specifier, const char *allowed[],
+			   const char *allowed_f2003[],
+			   const char *allowed_gnu[], gfc_char_t *value,
+			   const char *statement, bool warn, int *num)
+{
+int i;
+unsigned int len;
+len = gfc_wide_strlen (value);
+if (len > 0)
+{
+for (len--; len > 0; len--)
+if (value[len] != ' ')
+	break;
+len++;
+}
+for (i = 0; allowed[i]; i++)
+if (len == strlen (allowed[i])
+	&& gfc_wide_strncasecmp (value, allowed[i], strlen (allowed[i])) == 0)
+{
+	if (num)
+	  *num = i;
+return 1;
+}
+for (i = 0; allowed_f2003 && allowed_f2003[i]; i++)
+if (len == strlen (allowed_f2003[i])
+	&& gfc_wide_strncasecmp (value, allowed_f2003[i],
+				 strlen (allowed_f2003[i])) == 0)
+{
+	notification n = gfc_notification_std (GFC_STD_F2003);
+	if (n == WARNING || (warn && n == ERROR))
+	  {
+	    gfc_warning (0, "Fortran 2003: %s specifier in %s statement at %C "
+			 "has value %qs", specifier, statement,
+			 allowed_f2003[i]);
+	    return 1;
+	  }
+	else
+	  if (n == ERROR)
+	    {
+	      gfc_notify_std (GFC_STD_F2003, "%s specifier in "
+			      "%s statement at %C has value %qs", specifier,
+			      statement, allowed_f2003[i]);
+	      return 0;
+	    }
+	/* n == SILENT */
+	return 1;
+}
+for (i = 0; allowed_gnu && allowed_gnu[i]; i++)
+if (len == strlen (allowed_gnu[i])
+	&& gfc_wide_strncasecmp (value, allowed_gnu[i],
+				 strlen (allowed_gnu[i])) == 0)
+{
+	notification n = gfc_notification_std (GFC_STD_GNU);
+	if (n == WARNING || (warn && n == ERROR))
+	  {
+	    gfc_warning (0, "Extension: %s specifier in %s statement at %C "
+			 "has value %qs", specifier, statement,
+			 allowed_gnu[i]);
+	    return 1;
+	  }
+	else
+	  if (n == ERROR)
+	    {
+	      gfc_notify_std (GFC_STD_GNU, "%s specifier in "
+			      "%s statement at %C has value %qs", specifier,
+			      statement, allowed_gnu[i]);
+	      return 0;
+	    }
+	/* n == SILENT */
+	return 1;
+}
+if (warn)
+{
+char *s = gfc_widechar_to_char (value, -1);
+gfc_warning (0,
+		   "%s specifier in %s statement at %C has invalid value %qs",
+		   specifier, statement, s);
+free (s);
+return 1;
+}
+else
+{
+char *s = gfc_widechar_to_char (value, -1);
+gfc_error ("%s specifier in %s statement at %C has invalid value %qs",
+		 specifier, statement, s);
+free (s);
+return 0;
+}
+}
+/* Match an OPEN statement.  */
+match
+gfc_match_open (void)
+{
+gfc_open *open;
+match m;
+bool warn;
+m = gfc_match_char ('(');
+if (m == MATCH_NO)
+return m;
+open = XCNEW (gfc_open);
+m = match_open_element (open);
+if (m == MATCH_ERROR)
+goto cleanup;
+if (m == MATCH_NO)
+{
+m = gfc_match_expr (&open->unit);
+if (m == MATCH_ERROR)
+	goto cleanup;
+}
+for (;;)
+{
+if (gfc_match_char (')') == MATCH_YES)
+	break;
+if (gfc_match_char (',') != MATCH_YES)
+	goto syntax;
+m = match_open_element (open);
+if (m == MATCH_ERROR)
+	goto cleanup;
+if (m == MATCH_NO)
+	goto syntax;
+}
+if (gfc_match_eos () == MATCH_NO)
+goto syntax;
+if (gfc_pure (NULL))
+{
+gfc_error ("OPEN statement not allowed in PURE procedure at %C");
+goto cleanup;
+}
+gfc_unset_implicit_pure (NULL);
+warn = (open->err || open->iostat) ? true : false;
+/* Checks on NEWUNIT specifier.  */
+if (open->newunit)
+{
+if (open->unit)
+	{
+	  gfc_error ("UNIT specifier not allowed with NEWUNIT at %C");
+	  goto cleanup;
+	}
+if (!open->file && open->status)
+{
+	  if (open->status->expr_type == EXPR_CONSTANT
+	     && gfc_wide_strncasecmp (open->status->value.character.string,
+				       "scratch", 7) != 0)
+	   {
+	     gfc_error ("NEWUNIT specifier must have FILE= "
+			"or STATUS='scratch' at %C");
+	     goto cleanup;
+	   }
+	}
+}
+else if (!open->unit)
+{
+gfc_error ("OPEN statement at %C must have UNIT or NEWUNIT specified");
+goto cleanup;
+}
+/* Checks on the ACCESS specifier.  */
+if (open->access && open->access->expr_type == EXPR_CONSTANT)
+{
+static const char *access_f95[] = { "SEQUENTIAL", "DIRECT", NULL };
+static const char *access_f2003[] = { "STREAM", NULL };
+static const char *access_gnu[] = { "APPEND", NULL };
+if (!is_char_type ("ACCESS", open->access))
+	goto cleanup;
+if (!compare_to_allowed_values ("ACCESS", access_f95, access_f2003,
+				      access_gnu,
+				      open->access->value.character.string,
+				      "OPEN", warn))
+	goto cleanup;
+}
+/* Checks on the ACTION specifier.  */
+if (open->action && open->action->expr_type == EXPR_CONSTANT)
+{
+gfc_char_t *str = open->action->value.character.string;
+static const char *action[] = { "READ", "WRITE", "READWRITE", NULL };
+if (!is_char_type ("ACTION", open->action))
+	goto cleanup;
+if (!compare_to_allowed_values ("ACTION", action, NULL, NULL,
+				      str, "OPEN", warn))
+	goto cleanup;
+/* With READONLY, only allow ACTION='READ'.  */
+if (open->readonly && (gfc_wide_strlen (str) != 4
+			     || gfc_wide_strncasecmp (str, "READ", 4) != 0))
+	{
+	  gfc_error ("ACTION type conflicts with READONLY specifier at %C");
+	  goto cleanup;
+	}
+}
+/* If we see READONLY and no ACTION, set ACTION='READ'.  */
+else if (open->readonly && open->action == NULL)
+{
+open->action = gfc_get_character_expr (gfc_default_character_kind,
+					     &gfc_current_locus, "read", 4);
+}
+/* Checks on the ASYNCHRONOUS specifier.  */
+if (open->asynchronous)
+{
+if (!gfc_notify_std (GFC_STD_F2003, "ASYNCHRONOUS= at %C "
+			   "not allowed in Fortran 95"))
+	goto cleanup;
+if (!is_char_type ("ASYNCHRONOUS", open->asynchronous))
+	goto cleanup;
+if (open->asynchronous->expr_type == EXPR_CONSTANT)
+	{
+	  static const char * asynchronous[] = { "YES", "NO", NULL };
+	  if (!compare_to_allowed_values ("ASYNCHRONOUS", asynchronous,
+			NULL, NULL, open->asynchronous->value.character.string,
+			"OPEN", warn))
+	    goto cleanup;
+	}
+}
+/* Checks on the BLANK specifier.  */
+if (open->blank)
+{
+if (!gfc_notify_std (GFC_STD_F2003, "BLANK= at %C "
+			   "not allowed in Fortran 95"))
+	goto cleanup;
+if (!is_char_type ("BLANK", open->blank))
+	goto cleanup;
+if (open->blank->expr_type == EXPR_CONSTANT)
+	{
+	  static const char *blank[] = { "ZERO", "NULL", NULL };
+	  if (!compare_to_allowed_values ("BLANK", blank, NULL, NULL,
+					  open->blank->value.character.string,
+					  "OPEN", warn))
+	    goto cleanup;
+	}
+}
+/* Checks on the CARRIAGECONTROL specifier.  */
+if (open->cc)
+{
+if (!is_char_type ("CARRIAGECONTROL", open->cc))
+	goto cleanup;
+if (open->cc->expr_type == EXPR_CONSTANT)
+	{
+	  static const char *cc[] = { "LIST", "FORTRAN", "NONE", NULL };
+	  if (!compare_to_allowed_values ("CARRIAGECONTROL", cc, NULL, NULL,
+					  open->cc->value.character.string,
+					  "OPEN", warn))
+	    goto cleanup;
+	}
+}
+/* Checks on the DECIMAL specifier.  */
+if (open->decimal)
+{
+if (!gfc_notify_std (GFC_STD_F2003, "DECIMAL= at %C "
+			   "not allowed in Fortran 95"))
+	goto cleanup;
+if (!is_char_type ("DECIMAL", open->decimal))
+	goto cleanup;
+if (open->decimal->expr_type == EXPR_CONSTANT)
+	{
+	  static const char * decimal[] = { "COMMA", "POINT", NULL };
+	  if (!compare_to_allowed_values ("DECIMAL", decimal, NULL, NULL,
+					  open->decimal->value.character.string,
+					  "OPEN", warn))
+	    goto cleanup;
+	}
+}
+/* Checks on the DELIM specifier.  */
+if (open->delim)
+{
+if (open->delim->expr_type == EXPR_CONSTANT)
+	{
+	  static const char *delim[] = { "APOSTROPHE", "QUOTE", "NONE", NULL };
+	  if (!is_char_type ("DELIM", open->delim))
+	    goto cleanup;
+	  if (!compare_to_allowed_values ("DELIM", delim, NULL, NULL,
+					  open->delim->value.character.string,
+					  "OPEN", warn))
+	  goto cleanup;
+	}
+}
+/* Checks on the ENCODING specifier.  */
+if (open->encoding)
+{
+if (!gfc_notify_std (GFC_STD_F2003, "ENCODING= at %C "
+			   "not allowed in Fortran 95"))
+	goto cleanup;
+if (!is_char_type ("ENCODING", open->encoding))
+	goto cleanup;
+if (open->encoding->expr_type == EXPR_CONSTANT)
+	{
+	  static const char * encoding[] = { "DEFAULT", "UTF-8", NULL };
+	  if (!compare_to_allowed_values ("ENCODING", encoding, NULL, NULL,
+					  open->encoding->value.character.string,
+					  "OPEN", warn))
+	  goto cleanup;
+	}
+}
+/* Checks on the FORM specifier.  */
+if (open->form && open->form->expr_type == EXPR_CONSTANT)
+{
+static const char *form[] = { "FORMATTED", "UNFORMATTED", NULL };
+if (!is_char_type ("FORM", open->form))
+	goto cleanup;
+if (!compare_to_allowed_values ("FORM", form, NULL, NULL,
+				      open->form->value.character.string,
+				      "OPEN", warn))
+	goto cleanup;
+}
+/* Checks on the PAD specifier.  */
+if (open->pad && open->pad->expr_type == EXPR_CONSTANT)
+{
+static const char *pad[] = { "YES", "NO", NULL };
+if (!is_char_type ("PAD", open->pad))
+	goto cleanup;
+if (!compare_to_allowed_values ("PAD", pad, NULL, NULL,
+				      open->pad->value.character.string,
+				      "OPEN", warn))
+	goto cleanup;
+}
+/* Checks on the POSITION specifier.  */
+if (open->position && open->position->expr_type == EXPR_CONSTANT)
+{
+static const char *position[] = { "ASIS", "REWIND", "APPEND", NULL };
+if (!is_char_type ("POSITION", open->position))
+	goto cleanup;
+if (!compare_to_allowed_values ("POSITION", position, NULL, NULL,
+				      open->position->value.character.string,
+				      "OPEN", warn))
+	goto cleanup;
+}
+/* Checks on the ROUND specifier.  */
+if (open->round)
+{
+if (!gfc_notify_std (GFC_STD_F2003, "ROUND= at %C "
+			   "not allowed in Fortran 95"))
+goto cleanup;
+if (!is_char_type ("ROUND", open->round))
+	goto cleanup;
+if (open->round->expr_type == EXPR_CONSTANT)
+	{
+	  static const char * round[] = { "UP", "DOWN", "ZERO", "NEAREST",
+					  "COMPATIBLE", "PROCESSOR_DEFINED",
+					   NULL };
+	  if (!compare_to_allowed_values ("ROUND", round, NULL, NULL,
+					  open->round->value.character.string,
+					  "OPEN", warn))
+	  goto cleanup;
+	}
+}
+/* Checks on the SHARE specifier.  */
+if (open->share)
+{
+if (!is_char_type ("SHARE", open->share))
+	goto cleanup;
+if (open->share->expr_type == EXPR_CONSTANT)
+	{
+	  static const char *share[] = { "DENYNONE", "DENYRW", NULL };
+	  if (!compare_to_allowed_values ("SHARE", share, NULL, NULL,
+					  open->share->value.character.string,
+					  "OPEN", warn))
+	    goto cleanup;
+	}
+}
+/* Checks on the SIGN specifier.  */
+if (open->sign)
+{
+if (!gfc_notify_std (GFC_STD_F2003, "SIGN= at %C "
+			   "not allowed in Fortran 95"))
+	goto cleanup;
+if (!is_char_type ("SIGN", open->sign))
+	goto cleanup;
+if (open->sign->expr_type == EXPR_CONSTANT)
+	{
+	  static const char * sign[] = { "PLUS", "SUPPRESS", "PROCESSOR_DEFINED",
+					  NULL };
+	  if (!compare_to_allowed_values ("SIGN", sign, NULL, NULL,
+					  open->sign->value.character.string,
+					  "OPEN", warn))
+	  goto cleanup;
+	}
+}
+#define warn_or_error(...) \
+{ \
+if (warn) \
+gfc_warning (0, __VA_ARGS__); \
+else \
+{ \
+gfc_error (__VA_ARGS__); \
+goto cleanup; \
+} \
+}
+/* Checks on the RECL specifier.  */
+if (open->recl && open->recl->expr_type == EXPR_CONSTANT
+&& open->recl->ts.type == BT_INTEGER
+&& mpz_sgn (open->recl->value.integer) != 1)
+{
+warn_or_error ("RECL in OPEN statement at %C must be positive");
+}
+/* Checks on the STATUS specifier.  */
+if (open->status && open->status->expr_type == EXPR_CONSTANT)
+{
+static const char *status[] = { "OLD", "NEW", "SCRATCH",
+	"REPLACE", "UNKNOWN", NULL };
+if (!is_char_type ("STATUS", open->status))
+	goto cleanup;
+if (!compare_to_allowed_values ("STATUS", status, NULL, NULL,
+				      open->status->value.character.string,
+				      "OPEN", warn))
+	goto cleanup;
+/* F2003, 9.4.5: If the STATUS= specifier has the value NEW or REPLACE,
+	 the FILE= specifier shall appear.  */
+if (open->file == NULL
+	  && (gfc_wide_strncasecmp (open->status->value.character.string,
+				    "replace", 7) == 0
+	      || gfc_wide_strncasecmp (open->status->value.character.string,
+				       "new", 3) == 0))
+	{
+	  char *s = gfc_widechar_to_char (open->status->value.character.string,
+					  -1);
+	  warn_or_error ("The STATUS specified in OPEN statement at %C is "
+			 "%qs and no FILE specifier is present", s);
+	  free (s);
+	}
+/* F2003, 9.4.5: If the STATUS= specifier has the value SCRATCH,
+	 the FILE= specifier shall not appear.  */
+if (gfc_wide_strncasecmp (open->status->value.character.string,
+				"scratch", 7) == 0 && open->file)
+	{
+	  warn_or_error ("The STATUS specified in OPEN statement at %C "
+			 "cannot have the value SCRATCH if a FILE specifier "
+			 "is present");
+	}
+}
+/* Things that are not allowed for unformatted I/O.  */
+if (open->form && open->form->expr_type == EXPR_CONSTANT
+&& (open->delim || open->decimal || open->encoding || open->round
+	  || open->sign || open->pad || open->blank)
+&& gfc_wide_strncasecmp (open->form->value.character.string,
+			       "unformatted", 11) == 0)
+{
+const char *spec = (open->delim ? "DELIM "
+				      : (open->pad ? "PAD " : open->blank
+							    ? "BLANK " : ""));
+warn_or_error ("%s specifier at %C not allowed in OPEN statement for "
+		     "unformatted I/O", spec);
+}
+if (open->recl && open->access && open->access->expr_type == EXPR_CONSTANT
+&& gfc_wide_strncasecmp (open->access->value.character.string,
+			       "stream", 6) == 0)
+{
+warn_or_error ("RECL specifier not allowed in OPEN statement at %C for "
+		     "stream I/O");
+}
+if (open->position
+&& open->access && open->access->expr_type == EXPR_CONSTANT
+&& !(gfc_wide_strncasecmp (open->access->value.character.string,
+				 "sequential", 10) == 0
+	   || gfc_wide_strncasecmp (open->access->value.character.string,
+				    "stream", 6) == 0
+	   || gfc_wide_strncasecmp (open->access->value.character.string,
+				    "append", 6) == 0))
+{
+warn_or_error ("POSITION specifier in OPEN statement at %C only allowed "
+		     "for stream or sequential ACCESS");
+}
+#undef warn_or_error
+new_st.op = EXEC_OPEN;
+new_st.ext.open = open;
+return MATCH_YES;
+syntax:
+gfc_syntax_error (ST_OPEN);
+cleanup:
+gfc_free_open (open);
+return MATCH_ERROR;
+}
+/* Free a gfc_close structure an all its expressions.  */
+void
+gfc_free_close (gfc_close *close)
+{
+if (close == NULL)
+return;
+gfc_free_expr (close->unit);
+gfc_free_expr (close->iomsg);
+gfc_free_expr (close->iostat);
+gfc_free_expr (close->status);
+free (close);
+}
+/* Match elements of a CLOSE statement.  */
+static match
+match_close_element (gfc_close *close)
+{
+match m;
+m = match_etag (&tag_unit, &close->unit);
+if (m != MATCH_NO)
+return m;
+m = match_etag (&tag_status, &close->status);
+if (m != MATCH_NO)
+return m;
+m = match_etag (&tag_iomsg, &close->iomsg);
+if (m == MATCH_YES && !check_char_variable (close->iomsg))
+return MATCH_ERROR;
+if (m != MATCH_NO)
+return m;
+m = match_out_tag (&tag_iostat, &close->iostat);
+if (m != MATCH_NO)
+return m;
+m = match_ltag (&tag_err, &close->err);
+if (m != MATCH_NO)
+return m;
+return MATCH_NO;
+}
+/* Match a CLOSE statement.  */
+match
+gfc_match_close (void)
+{
+gfc_close *close;
+match m;
+bool warn;
+m = gfc_match_char ('(');
+if (m == MATCH_NO)
+return m;
+close = XCNEW (gfc_close);
+m = match_close_element (close);
+if (m == MATCH_ERROR)
+goto cleanup;
+if (m == MATCH_NO)
+{
+m = gfc_match_expr (&close->unit);
+if (m == MATCH_NO)
+	goto syntax;
+if (m == MATCH_ERROR)
+	goto cleanup;
+}
+for (;;)
+{
+if (gfc_match_char (')') == MATCH_YES)
+	break;
+if (gfc_match_char (',') != MATCH_YES)
+	goto syntax;
+m = match_close_element (close);
+if (m == MATCH_ERROR)
+	goto cleanup;
+if (m == MATCH_NO)
+	goto syntax;
+}
+if (gfc_match_eos () == MATCH_NO)
+goto syntax;
+if (gfc_pure (NULL))
+{
+gfc_error ("CLOSE statement not allowed in PURE procedure at %C");
+goto cleanup;
+}
+gfc_unset_implicit_pure (NULL);
+warn = (close->iostat || close->err) ? true : false;
+/* Checks on the STATUS specifier.  */
+if (close->status && close->status->expr_type == EXPR_CONSTANT)
+{
+static const char *status[] = { "KEEP", "DELETE", NULL };
+if (!is_char_type ("STATUS", close->status))
+	goto cleanup;
+if (!compare_to_allowed_values ("STATUS", status, NULL, NULL,
+				      close->status->value.character.string,
+				      "CLOSE", warn))
+	goto cleanup;
+}
+new_st.op = EXEC_CLOSE;
+new_st.ext.close = close;
+return MATCH_YES;
+syntax:
+gfc_syntax_error (ST_CLOSE);
+cleanup:
+gfc_free_close (close);
+return MATCH_ERROR;
+}
+/* Resolve everything in a gfc_close structure.  */
+bool
+gfc_resolve_close (gfc_close *close)
+{
+RESOLVE_TAG (&tag_unit, close->unit);
+RESOLVE_TAG (&tag_iomsg, close->iomsg);
+RESOLVE_TAG (&tag_iostat, close->iostat);
+RESOLVE_TAG (&tag_status, close->status);
+if (!gfc_reference_st_label (close->err, ST_LABEL_TARGET))
+return false;
+if (close->unit == NULL)
+{
+/* Find a locus from one of the arguments to close, when UNIT is
+	 not specified.  */
+locus loc = gfc_current_locus;
+if (close->status)
+	loc = close->status->where;
+else if (close->iostat)
+	loc = close->iostat->where;
+else if (close->iomsg)
+	loc = close->iomsg->where;
+else if (close->err)
+	loc = close->err->where;
+gfc_error ("CLOSE statement at %L requires a UNIT number", &loc);
+return false;
+}
+if (close->unit->expr_type == EXPR_CONSTANT
+&& close->unit->ts.type == BT_INTEGER
+&& mpz_sgn (close->unit->value.integer) < 0)
+{
+gfc_error ("UNIT number in CLOSE statement at %L must be non-negative",
+		 &close->unit->where);
+}
+return true;
+}
+/* Free a gfc_filepos structure.  */
+void
+gfc_free_filepos (gfc_filepos *fp)
+{
+gfc_free_expr (fp->unit);
+gfc_free_expr (fp->iomsg);
+gfc_free_expr (fp->iostat);
+free (fp);
+}
+/* Match elements of a REWIND, BACKSPACE, ENDFILE, or FLUSH statement.  */
+static match
+match_file_element (gfc_filepos *fp)
+{
+match m;
+m = match_etag (&tag_unit, &fp->unit);
+if (m != MATCH_NO)
+return m;
+m = match_etag (&tag_iomsg, &fp->iomsg);
+if (m == MATCH_YES && !check_char_variable (fp->iomsg))
+return MATCH_ERROR;
+if (m != MATCH_NO)
+return m;
+m = match_out_tag (&tag_iostat, &fp->iostat);
+if (m != MATCH_NO)
+return m;
+m = match_ltag (&tag_err, &fp->err);
+if (m != MATCH_NO)
+return m;
+return MATCH_NO;
+}
+/* Match the second half of the file-positioning statements, REWIND,
+BACKSPACE, ENDFILE, or the FLUSH statement.  */
+static match
+match_filepos (gfc_statement st, gfc_exec_op op)
+{
+gfc_filepos *fp;
+match m;
+fp = XCNEW (gfc_filepos);
+if (gfc_match_char ('(') == MATCH_NO)
+{
+m = gfc_match_expr (&fp->unit);
+if (m == MATCH_ERROR)
+	goto cleanup;
+if (m == MATCH_NO)
+	goto syntax;
+goto done;
+}
+m = match_file_element (fp);
+if (m == MATCH_ERROR)
+goto done;
+if (m == MATCH_NO)
+{
+m = gfc_match_expr (&fp->unit);
+if (m == MATCH_ERROR || m == MATCH_NO)
+	goto syntax;
+}
+for (;;)
+{
+if (gfc_match_char (')') == MATCH_YES)
+	break;
+if (gfc_match_char (',') != MATCH_YES)
+	goto syntax;
+m = match_file_element (fp);
+if (m == MATCH_ERROR)
+	goto cleanup;
+if (m == MATCH_NO)
+	goto syntax;
+}
+done:
+if (gfc_match_eos () != MATCH_YES)
+goto syntax;
+if (gfc_pure (NULL))
+{
+gfc_error ("%s statement not allowed in PURE procedure at %C",
+		 gfc_ascii_statement (st));
+goto cleanup;
+}
+gfc_unset_implicit_pure (NULL);
+new_st.op = op;
+new_st.ext.filepos = fp;
+return MATCH_YES;
+syntax:
+gfc_syntax_error (st);
+cleanup:
+gfc_free_filepos (fp);
+return MATCH_ERROR;
+}
+bool
+gfc_resolve_filepos (gfc_filepos *fp)
+{
+RESOLVE_TAG (&tag_unit, fp->unit);
+RESOLVE_TAG (&tag_iostat, fp->iostat);
+RESOLVE_TAG (&tag_iomsg, fp->iomsg);
+if (!gfc_reference_st_label (fp->err, ST_LABEL_TARGET))
+return false;
+if (!fp->unit && (fp->iostat || fp->iomsg))
+{
+locus where;
+where = fp->iostat ? fp->iostat->where : fp->iomsg->where;
+gfc_error ("UNIT number missing in statement at %L", &where);
+return false;
+}
+if (fp->unit->expr_type == EXPR_CONSTANT
+&& fp->unit->ts.type == BT_INTEGER
+&& mpz_sgn (fp->unit->value.integer) < 0)
+{
+gfc_error ("UNIT number in statement at %L must be non-negative",
+		 &fp->unit->where);
+return false;
+}
+return true;
+}
+/* Match the file positioning statements: ENDFILE, BACKSPACE, REWIND,
+and the FLUSH statement.  */
+match
+gfc_match_endfile (void)
+{
+return match_filepos (ST_END_FILE, EXEC_ENDFILE);
+}
+match
+gfc_match_backspace (void)
+{
+return match_filepos (ST_BACKSPACE, EXEC_BACKSPACE);
+}
+match
+gfc_match_rewind (void)
+{
+return match_filepos (ST_REWIND, EXEC_REWIND);
+}
+match
+gfc_match_flush (void)
+{
+if (!gfc_notify_std (GFC_STD_F2003, "FLUSH statement at %C"))
+return MATCH_ERROR;
+return match_filepos (ST_FLUSH, EXEC_FLUSH);
+}
+/******************** Data Transfer Statements *********************/
+/* Return a default unit number.  */
+static gfc_expr *
+default_unit (io_kind k)
+{
+int unit;
+if (k == M_READ)
+unit = 5;
+else
+unit = 6;
+return gfc_get_int_expr (gfc_default_integer_kind, NULL, unit);
+}
+/* Match a unit specification for a data transfer statement.  */
+static match
+match_dt_unit (io_kind k, gfc_dt *dt)
+{
+gfc_expr *e;
+char c;
+if (gfc_match_char ('*') == MATCH_YES)
+{
+if (dt->io_unit != NULL)
+	goto conflict;
+dt->io_unit = default_unit (k);
+c = gfc_peek_ascii_char ();
+if (c == ')')
+	gfc_error_now ("Missing format with default unit at %C");
+return MATCH_YES;
+}
+if (gfc_match_expr (&e) == MATCH_YES)
+{
+if (dt->io_unit != NULL)
+	{
+	  gfc_free_expr (e);
+	  goto conflict;
+	}
+dt->io_unit = e;
+return MATCH_YES;
+}
+return MATCH_NO;
+conflict:
+gfc_error ("Duplicate UNIT specification at %C");
+return MATCH_ERROR;
+}
+/* Match a format specification.  */
+static match
+match_dt_format (gfc_dt *dt)
+{
+locus where;
+gfc_expr *e;
+gfc_st_label *label;
+match m;
+where = gfc_current_locus;
+if (gfc_match_char ('*') == MATCH_YES)
+{
+if (dt->format_expr != NULL || dt->format_label != NULL)
+	goto conflict;
+dt->format_label = &format_asterisk;
+return MATCH_YES;
+}
+if ((m = gfc_match_st_label (&label)) == MATCH_YES)
+{
+char c;
+/* Need to check if the format label is actually either an operand
+	 to a user-defined operator or is a kind type parameter.  That is,
+	 print 2.ip.8      ! .ip. is a user-defined operator return CHARACTER.
+	 print 1_'(I0)', i ! 1_'(I0)' is a default character string.  */
+gfc_gobble_whitespace ();
+c = gfc_peek_ascii_char ();
+if (c == '.' || c == '_')
+	gfc_current_locus = where;
+else
+	{
+	  if (dt->format_expr != NULL || dt->format_label != NULL)
+	    {
+	      gfc_free_st_label (label);
+	      goto conflict;
+	    }
+	  if (!gfc_reference_st_label (label, ST_LABEL_FORMAT))
+	    return MATCH_ERROR;
+	  dt->format_label = label;
+	  return MATCH_YES;
+	}
+}
+else if (m == MATCH_ERROR)
+/* The label was zero or too large.  Emit the correct diagnosis.  */
+return MATCH_ERROR;
+if (gfc_match_expr (&e) == MATCH_YES)
+{
+if (dt->format_expr != NULL || dt->format_label != NULL)
+	{
+	  gfc_free_expr (e);
+	  goto conflict;
+	}
+dt->format_expr = e;
+return MATCH_YES;
+}
+gfc_current_locus = where;	/* The only case where we have to restore */
+return MATCH_NO;
+conflict:
+gfc_error ("Duplicate format specification at %C");
+return MATCH_ERROR;
+}
+/* Check for formatted read and write DTIO procedures.  */
+static bool
+dtio_procs_present (gfc_symbol *sym, io_kind k)
+{
+gfc_symbol *derived;
+if (sym && sym->ts.u.derived)
+{
+if (sym->ts.type == BT_CLASS && CLASS_DATA (sym))
+	derived = CLASS_DATA (sym)->ts.u.derived;
+else if (sym->ts.type == BT_DERIVED)
+	derived = sym->ts.u.derived;
+else
+	return false;
+if ((k == M_WRITE || k == M_PRINT) &&
+	  (gfc_find_specific_dtio_proc (derived, true, true) != NULL))
+	return true;
+if ((k == M_READ) &&
+	  (gfc_find_specific_dtio_proc (derived, false, true) != NULL))
+	return true;
+}
+return false;
+}
+/* Traverse a namelist that is part of a READ statement to make sure
+that none of the variables in the namelist are INTENT(IN).  Returns
+nonzero if we find such a variable.  */
+static int
+check_namelist (gfc_symbol *sym)
+{
+gfc_namelist *p;
+for (p = sym->namelist; p; p = p->next)
+if (p->sym->attr.intent == INTENT_IN)
+{
+	gfc_error ("Symbol %qs in namelist %qs is INTENT(IN) at %C",
+		   p->sym->name, sym->name);
+	return 1;
+}
+return 0;
+}
+/* Match a single data transfer element.  */
+static match
+match_dt_element (io_kind k, gfc_dt *dt)
+{
+char name[GFC_MAX_SYMBOL_LEN + 1];
+gfc_symbol *sym;
+match m;
+if (gfc_match (" unit =") == MATCH_YES)
+{
+m = match_dt_unit (k, dt);
+if (m != MATCH_NO)
+	return m;
+}
+if (gfc_match (" fmt =") == MATCH_YES)
+{
+m = match_dt_format (dt);
+if (m != MATCH_NO)
+	return m;
+}
+if (gfc_match (" nml = %n", name) == MATCH_YES)
+{
+if (dt->namelist != NULL)
+	{
+	  gfc_error ("Duplicate NML specification at %C");
+	  return MATCH_ERROR;
+	}
+if (gfc_find_symbol (name, NULL, 1, &sym))
+	return MATCH_ERROR;
+if (sym == NULL || sym->attr.flavor != FL_NAMELIST)
+	{
+	  gfc_error ("Symbol %qs at %C must be a NAMELIST group name",
+		     sym != NULL ? sym->name : name);
+	  return MATCH_ERROR;
+	}
+dt->namelist = sym;
+if (k == M_READ && check_namelist (sym))
+	return MATCH_ERROR;
+return MATCH_YES;
+}
+m = match_etag (&tag_e_async, &dt->asynchronous);
+if (m == MATCH_YES && !is_char_type ("ASYNCHRONOUS", dt->asynchronous))
+return MATCH_ERROR;
+if (m != MATCH_NO)
+return m;
+m = match_etag (&tag_e_blank, &dt->blank);
+if (m != MATCH_NO)
+return m;
+m = match_etag (&tag_e_delim, &dt->delim);
+if (m != MATCH_NO)
+return m;
+m = match_etag (&tag_e_pad, &dt->pad);
+if (m != MATCH_NO)
+return m;
+m = match_etag (&tag_e_sign, &dt->sign);
+if (m != MATCH_NO)
+return m;
+m = match_etag (&tag_e_round, &dt->round);
+if (m != MATCH_NO)
+return m;
+m = match_out_tag (&tag_id, &dt->id);
+if (m != MATCH_NO)
+return m;
+m = match_etag (&tag_e_decimal, &dt->decimal);
+if (m != MATCH_NO)
+return m;
+m = match_etag (&tag_rec, &dt->rec);
+if (m != MATCH_NO)
+return m;
+m = match_etag (&tag_spos, &dt->pos);
+if (m != MATCH_NO)
+return m;
+m = match_etag (&tag_iomsg, &dt->iomsg);
+if (m == MATCH_YES && !check_char_variable (dt->iomsg))
+return MATCH_ERROR;
+if (m != MATCH_NO)
+return m;
+m = match_out_tag (&tag_iostat, &dt->iostat);
+if (m != MATCH_NO)
+return m;
+m = match_ltag (&tag_err, &dt->err);
+if (m == MATCH_YES)
+dt->err_where = gfc_current_locus;
+if (m != MATCH_NO)
+return m;
+m = match_etag (&tag_advance, &dt->advance);
+if (m != MATCH_NO)
+return m;
+m = match_out_tag (&tag_size, &dt->size);
+if (m != MATCH_NO)
+return m;
+m = match_ltag (&tag_end, &dt->end);
+if (m == MATCH_YES)
+{
+if (k == M_WRITE)
+{
+	 gfc_error ("END tag at %C not allowed in output statement");
+	 return MATCH_ERROR;
+}
+dt->end_where = gfc_current_locus;
+}
+if (m != MATCH_NO)
+return m;
+m = match_ltag (&tag_eor, &dt->eor);
+if (m == MATCH_YES)
+dt->eor_where = gfc_current_locus;
+if (m != MATCH_NO)
+return m;
+return MATCH_NO;
+}
+/* Free a data transfer structure and everything below it.  */
+void
+gfc_free_dt (gfc_dt *dt)
+{
+if (dt == NULL)
+return;
+gfc_free_expr (dt->io_unit);
+gfc_free_expr (dt->format_expr);
+gfc_free_expr (dt->rec);
+gfc_free_expr (dt->advance);
+gfc_free_expr (dt->iomsg);
+gfc_free_expr (dt->iostat);
+gfc_free_expr (dt->size);
+gfc_free_expr (dt->pad);
+gfc_free_expr (dt->delim);
+gfc_free_expr (dt->sign);
+gfc_free_expr (dt->round);
+gfc_free_expr (dt->blank);
+gfc_free_expr (dt->decimal);
+gfc_free_expr (dt->pos);
+gfc_free_expr (dt->dt_io_kind);
+/* dt->extra_comma is a link to dt_io_kind if it is set.  */
+free (dt);
+}
+/* Resolve everything in a gfc_dt structure.  */
+bool
+gfc_resolve_dt (gfc_dt *dt, locus *loc)
+{
+gfc_expr *e;
+io_kind k;
+/* This is set in any case.  */
+gcc_assert (dt->dt_io_kind);
+k = dt->dt_io_kind->value.iokind;
+RESOLVE_TAG (&tag_format, dt->format_expr);
+RESOLVE_TAG (&tag_rec, dt->rec);
+RESOLVE_TAG (&tag_spos, dt->pos);
+RESOLVE_TAG (&tag_advance, dt->advance);
+RESOLVE_TAG (&tag_id, dt->id);
+RESOLVE_TAG (&tag_iomsg, dt->iomsg);
+RESOLVE_TAG (&tag_iostat, dt->iostat);
+RESOLVE_TAG (&tag_size, dt->size);
+RESOLVE_TAG (&tag_e_pad, dt->pad);
+RESOLVE_TAG (&tag_e_delim, dt->delim);
+RESOLVE_TAG (&tag_e_sign, dt->sign);
+RESOLVE_TAG (&tag_e_round, dt->round);
+RESOLVE_TAG (&tag_e_blank, dt->blank);
+RESOLVE_TAG (&tag_e_decimal, dt->decimal);
+RESOLVE_TAG (&tag_e_async, dt->asynchronous);
+e = dt->io_unit;
+if (e == NULL)
+{
+gfc_error ("UNIT not specified at %L", loc);
+return false;
+}
+if (gfc_resolve_expr (e)
+&& (e->ts.type != BT_INTEGER
+	  && (e->ts.type != BT_CHARACTER || e->expr_type != EXPR_VARIABLE)))
+{
+/* If there is no extra comma signifying the "format" form of the IO
+	 statement, then this must be an error.  */
+if (!dt->extra_comma)
+	{
+	  gfc_error ("UNIT specification at %L must be an INTEGER expression "
+		     "or a CHARACTER variable", &e->where);
+	  return false;
+	}
+else
+	{
+	  /* At this point, we have an extra comma.  If io_unit has arrived as
+	     type character, we assume its really the "format" form of the I/O
+	     statement.  We set the io_unit to the default unit and format to
+	     the character expression.  See F95 Standard section 9.4.  */
+	  if (e->ts.type == BT_CHARACTER && (k == M_READ || k == M_PRINT))
+	    {
+	      dt->format_expr = dt->io_unit;
+	      dt->io_unit = default_unit (k);
+	      /* Nullify this pointer now so that a warning/error is not
+		 triggered below for the "Extension".  */
+	      dt->extra_comma = NULL;
+	    }
+	  if (k == M_WRITE)
+	    {
+	      gfc_error ("Invalid form of WRITE statement at %L, UNIT required",
+			 &dt->extra_comma->where);
+	      return false;
+	    }
+	}
+}
+if (e->ts.type == BT_CHARACTER)
+{
+if (gfc_has_vector_index (e))
+	{
+	  gfc_error ("Internal unit with vector subscript at %L", &e->where);
+	  return false;
+	}
+/* If we are writing, make sure the internal unit can be changed.  */
+gcc_assert (k != M_PRINT);
+if (k == M_WRITE
+	  && !gfc_check_vardef_context (e, false, false, false,
+					_("internal unit in WRITE")))
+	return false;
+}
+if (e->rank && e->ts.type != BT_CHARACTER)
+{
+gfc_error ("External IO UNIT cannot be an array at %L", &e->where);
+return false;
+}
+if (e->expr_type == EXPR_CONSTANT && e->ts.type == BT_INTEGER
+&& mpz_sgn (e->value.integer) < 0)
+{
+gfc_error ("UNIT number in statement at %L must be non-negative",
+		 &e->where);
+return false;
+}
+/* If we are reading and have a namelist, check that all namelist symbols
+can appear in a variable definition context.  */
+if (dt->namelist)
+{
+gfc_namelist* n;
+for (n = dt->namelist->namelist; n; n = n->next)
+	{
+	  gfc_expr* e;
+	  bool t;
+	  if (k == M_READ)
+	    {
+	      e = gfc_get_variable_expr (gfc_find_sym_in_symtree (n->sym));
+	      t = gfc_check_vardef_context (e, false, false, false, NULL);
+	      gfc_free_expr (e);
+	      if (!t)
+		{
+		  gfc_error ("NAMELIST %qs in READ statement at %L contains"
+			     " the symbol %qs which may not appear in a"
+			     " variable definition context",
+			     dt->namelist->name, loc, n->sym->name);
+		  return false;
+		}
+	    }
+	  t = dtio_procs_present (n->sym, k);
+	  if (n->sym->ts.type == BT_CLASS && !t)
+	    {
+	      gfc_error ("NAMELIST object %qs in namelist %qs at %L is "
+			 "polymorphic and requires a defined input/output "
+			 "procedure", n->sym->name, dt->namelist->name, loc);
+	      return false;
+	    }
+	  if ((n->sym->ts.type == BT_DERIVED)
+	      && (n->sym->ts.u.derived->attr.alloc_comp
+		  || n->sym->ts.u.derived->attr.pointer_comp))
+	    {
+	      if (!gfc_notify_std (GFC_STD_F2003, "NAMELIST object %qs in "
+				   "namelist %qs at %L with ALLOCATABLE "
+				   "or POINTER components", n->sym->name,
+				   dt->namelist->name, loc))
+		return false;
+	      if (!t)
+		{
+		  gfc_error ("NAMELIST object %qs in namelist %qs at %L has "
+			     "ALLOCATABLE or POINTER components and thus requires "
+			     "a defined input/output procedure", n->sym->name,
+			     dt->namelist->name, loc);
+		  return false;
+		}
+	    }
+	}
+}
+if (dt->extra_comma
+&& !gfc_notify_std (GFC_STD_LEGACY, "Comma before i/o item list at %L",
+			  &dt->extra_comma->where))
+return false;
+if (dt->err)
+{
+if (!gfc_reference_st_label (dt->err, ST_LABEL_TARGET))
+	return false;
+if (dt->err->defined == ST_LABEL_UNKNOWN)
+	{
+	  gfc_error ("ERR tag label %d at %L not defined",
+		      dt->err->value, &dt->err_where);
+	  return false;
+	}
+}
+if (dt->end)
+{
+if (!gfc_reference_st_label (dt->end, ST_LABEL_TARGET))
+	return false;
+if (dt->end->defined == ST_LABEL_UNKNOWN)
+	{
+	  gfc_error ("END tag label %d at %L not defined",
+		      dt->end->value, &dt->end_where);
+	  return false;
+	}
+}
+if (dt->eor)
+{
+if (!gfc_reference_st_label (dt->eor, ST_LABEL_TARGET))
+	return false;
+if (dt->eor->defined == ST_LABEL_UNKNOWN)
+	{
+	  gfc_error ("EOR tag label %d at %L not defined",
+		      dt->eor->value, &dt->eor_where);
+	  return false;
+	}
+}
+/* Check the format label actually exists.  */
+if (dt->format_label && dt->format_label != &format_asterisk
+&& dt->format_label->defined == ST_LABEL_UNKNOWN)
+{
+gfc_error ("FORMAT label %d at %L not defined", dt->format_label->value,
+		 loc);
+return false;
+}
+return true;
+}
+/* Given an io_kind, return its name.  */
+static const char *
+io_kind_name (io_kind k)
+{
+const char *name;
+switch (k)
+{
+case M_READ:
+name = "READ";
+break;
+case M_WRITE:
+name = "WRITE";
+break;
+case M_PRINT:
+name = "PRINT";
+break;
+case M_INQUIRE:
+name = "INQUIRE";
+break;
+default:
+gfc_internal_error ("io_kind_name(): bad I/O-kind");
+}
+return name;
+}
+/* Match an IO iteration statement of the form:
+( [<IO element> ,] <IO element>, I = <expr>, <expr> [, <expr> ] )
+which is equivalent to a single IO element.  This function is
+mutually recursive with match_io_element().  */
+static match match_io_element (io_kind, gfc_code **);
+static match
+match_io_iterator (io_kind k, gfc_code **result)
+{
+gfc_code *head, *tail, *new_code;
+gfc_iterator *iter;
+locus old_loc;
+match m;
+int n;
+iter = NULL;
+head = NULL;
+old_loc = gfc_current_locus;
+if (gfc_match_char ('(') != MATCH_YES)
+return MATCH_NO;
+m = match_io_element (k, &head);
+tail = head;
+if (m != MATCH_YES || gfc_match_char (',') != MATCH_YES)
+{
+m = MATCH_NO;
+goto cleanup;
+}
+/* Can't be anything but an IO iterator.  Build a list.  */
+iter = gfc_get_iterator ();
+for (n = 1;; n++)
+{
+m = gfc_match_iterator (iter, 0);
+if (m == MATCH_ERROR)
+	goto cleanup;
+if (m == MATCH_YES)
+	{
+	  gfc_check_do_variable (iter->var->symtree);
+	  break;
+	}
+m = match_io_element (k, &new_code);
+if (m == MATCH_ERROR)
+	goto cleanup;
+if (m == MATCH_NO)
+	{
+	  if (n > 2)
+	    goto syntax;
+	  goto cleanup;
+	}
+tail = gfc_append_code (tail, new_code);
+if (gfc_match_char (',') != MATCH_YES)
+	{
+	  if (n > 2)
+	    goto syntax;
+	  m = MATCH_NO;
+	  goto cleanup;
+	}
+}
+if (gfc_match_char (')') != MATCH_YES)
+goto syntax;
+new_code = gfc_get_code (EXEC_DO);
+new_code->ext.iterator = iter;
+new_code->block = gfc_get_code (EXEC_DO);
+new_code->block->next = head;
+*result = new_code;
+return MATCH_YES;
+syntax:
+gfc_error ("Syntax error in I/O iterator at %C");
+m = MATCH_ERROR;
+cleanup:
+gfc_free_iterator (iter, 1);
+gfc_free_statements (head);
+gfc_current_locus = old_loc;
+return m;
+}
+/* Match a single element of an IO list, which is either a single
+expression or an IO Iterator.  */
+static match
+match_io_element (io_kind k, gfc_code **cpp)
+{
+gfc_expr *expr;
+gfc_code *cp;
+match m;
+expr = NULL;
+m = match_io_iterator (k, cpp);
+if (m == MATCH_YES)
+return MATCH_YES;
+if (k == M_READ)
+{
+m = gfc_match_variable (&expr, 0);
+if (m == MATCH_NO)
+	gfc_error ("Expected variable in READ statement at %C");
+}
+else
+{
+m = gfc_match_expr (&expr);
+if (m == MATCH_NO)
+	gfc_error ("Expected expression in %s statement at %C",
+		   io_kind_name (k));
+}
+if (m == MATCH_YES && k == M_READ && gfc_check_do_variable (expr->symtree))
+m = MATCH_ERROR;
+if (m != MATCH_YES)
+{
+gfc_free_expr (expr);
+return MATCH_ERROR;
+}
+cp = gfc_get_code (EXEC_TRANSFER);
+cp->expr1 = expr;
+if (k != M_INQUIRE)
+cp->ext.dt = current_dt;
+*cpp = cp;
+return MATCH_YES;
+}
+/* Match an I/O list, building gfc_code structures as we go.  */
+static match
+match_io_list (io_kind k, gfc_code **head_p)
+{
+gfc_code *head, *tail, *new_code;
+match m;
+*head_p = head = tail = NULL;
+if (gfc_match_eos () == MATCH_YES)
+return MATCH_YES;
+for (;;)
+{
+m = match_io_element (k, &new_code);
+if (m == MATCH_ERROR)
+	goto cleanup;
+if (m == MATCH_NO)
+	goto syntax;
+tail = gfc_append_code (tail, new_code);
+if (head == NULL)
+	head = new_code;
+if (gfc_match_eos () == MATCH_YES)
+	break;
+if (gfc_match_char (',') != MATCH_YES)
+	goto syntax;
+}
+*head_p = head;
+return MATCH_YES;
+syntax:
+gfc_error ("Syntax error in %s statement at %C", io_kind_name (k));
+cleanup:
+gfc_free_statements (head);
+return MATCH_ERROR;
+}
+/* Attach the data transfer end node.  */
+static void
+terminate_io (gfc_code *io_code)
+{
+gfc_code *c;
+if (io_code == NULL)
+io_code = new_st.block;
+c = gfc_get_code (EXEC_DT_END);
+/* Point to structure that is already there */
+c->ext.dt = new_st.ext.dt;
+gfc_append_code (io_code, c);
+}
+/* Check the constraints for a data transfer statement.  The majority of the
+constraints appearing in 9.4 of the standard appear here.  Some are handled
+in resolve_tag and others in gfc_resolve_dt.  Also set the async_io_dt flag
+and, if necessary, the asynchronous flag on the SIZE argument.  */
+static match
+check_io_constraints (io_kind k, gfc_dt *dt, gfc_code *io_code,
+		      locus *spec_end)
+{
+#define io_constraint(condition,msg,arg)\
+if (condition) \
+{\
+gfc_error(msg,arg);\
+m = MATCH_ERROR;\
+}
+match m;
+gfc_expr *expr;
+gfc_symbol *sym = NULL;
+bool warn, unformatted;
+warn = (dt->err || dt->iostat) ? true : false;
+unformatted = dt->format_expr == NULL && dt->format_label == NULL
+		&& dt->namelist == NULL;
+m = MATCH_YES;
+expr = dt->io_unit;
+if (expr && expr->expr_type == EXPR_VARIABLE
+&& expr->ts.type == BT_CHARACTER)
+{
+sym = expr->symtree->n.sym;
+io_constraint (k == M_WRITE && sym->attr.intent == INTENT_IN,
+		     "Internal file at %L must not be INTENT(IN)",
+		     &expr->where);
+io_constraint (gfc_has_vector_index (dt->io_unit),
+		     "Internal file incompatible with vector subscript at %L",
+		     &expr->where);
+io_constraint (dt->rec != NULL,
+		     "REC tag at %L is incompatible with internal file",
+		     &dt->rec->where);
+io_constraint (dt->pos != NULL,
+		     "POS tag at %L is incompatible with internal file",
+		     &dt->pos->where);
+io_constraint (unformatted,
+		     "Unformatted I/O not allowed with internal unit at %L",
+		     &dt->io_unit->where);
+io_constraint (dt->asynchronous != NULL,
+		     "ASYNCHRONOUS tag at %L not allowed with internal file",
+		     &dt->asynchronous->where);
+if (dt->namelist != NULL)
+	{
+	  if (!gfc_notify_std (GFC_STD_F2003, "Internal file at %L with "
+			       "namelist", &expr->where))
+	    m = MATCH_ERROR;
+	}
+io_constraint (dt->advance != NULL,
+		     "ADVANCE tag at %L is incompatible with internal file",
+		     &dt->advance->where);
+}
+if (expr && expr->ts.type != BT_CHARACTER)
+{
+io_constraint (gfc_pure (NULL) && (k == M_READ || k == M_WRITE),
+		     "IO UNIT in %s statement at %C must be "
+		     "an internal file in a PURE procedure",
+		     io_kind_name (k));
+if (k == M_READ || k == M_WRITE)
+	gfc_unset_implicit_pure (NULL);
+}
+if (k != M_READ)
+{
+io_constraint (dt->end, "END tag not allowed with output at %L",
+		     &dt->end_where);
+io_constraint (dt->eor, "EOR tag not allowed with output at %L",
+		     &dt->eor_where);
+io_constraint (dt->blank, "BLANK= specifier not allowed with output at %L",
+		     &dt->blank->where);
+io_constraint (dt->pad, "PAD= specifier not allowed with output at %L",
+		     &dt->pad->where);
+io_constraint (dt->size, "SIZE= specifier not allowed with output at %L",
+		     &dt->size->where);
+}
+else
+{
+io_constraint (dt->size && dt->advance == NULL,
+		     "SIZE tag at %L requires an ADVANCE tag",
+		     &dt->size->where);
+io_constraint (dt->eor && dt->advance == NULL,
+		     "EOR tag at %L requires an ADVANCE tag",
+		     &dt->eor_where);
+}
+if (dt->asynchronous)
+{
+int num;
+static const char * asynchronous[] = { "YES", "NO", NULL };
+if (!gfc_reduce_init_expr (dt->asynchronous))
+	{
+	  gfc_error ("ASYNCHRONOUS= specifier at %L must be an initialization "
+		     "expression", &dt->asynchronous->where);
+	  return MATCH_ERROR;
+	}
+if (!is_char_type ("ASYNCHRONOUS", dt->asynchronous))
+	return MATCH_ERROR;
+if (!compare_to_allowed_values
+		("ASYNCHRONOUS", asynchronous, NULL, NULL,
+		 dt->asynchronous->value.character.string,
+		 io_kind_name (k), warn, &num))
+	return MATCH_ERROR;
+/* Best to put this here because the yes/no info is still around.  */
+async_io_dt = num == 0;
+if (async_io_dt && dt->size)
+	dt->size->symtree->n.sym->attr.asynchronous = 1;
+}
+else
+async_io_dt = false;
+if (dt->id)
+{
+bool not_yes
+	= !dt->asynchronous
+	  || gfc_wide_strlen (dt->asynchronous->value.character.string) != 3
+	  || gfc_wide_strncasecmp (dt->asynchronous->value.character.string,
+				   "yes", 3) != 0;
+io_constraint (not_yes,
+		     "ID= specifier at %L must be with ASYNCHRONOUS='yes' "
+		     "specifier", &dt->id->where);
+}
+if (dt->decimal)
+{
+if (!gfc_notify_std (GFC_STD_F2003, "DECIMAL= at %C "
+			   "not allowed in Fortran 95"))
+	return MATCH_ERROR;
+if (dt->decimal->expr_type == EXPR_CONSTANT)
+	{
+	  static const char * decimal[] = { "COMMA", "POINT", NULL };
+if (!is_char_type ("DECIMAL", dt->decimal))
+	return MATCH_ERROR;
+	  if (!compare_to_allowed_values ("DECIMAL", decimal, NULL, NULL,
+					  dt->decimal->value.character.string,
+					  io_kind_name (k), warn))
+	    return MATCH_ERROR;
+	  io_constraint (unformatted,
+			 "the DECIMAL= specifier at %L must be with an "
+			 "explicit format expression", &dt->decimal->where);
+	}
+}
+if (dt->blank)
+{
+if (!gfc_notify_std (GFC_STD_F2003, "BLANK= at %C "
+			   "not allowed in Fortran 95"))
+	return MATCH_ERROR;
+if (!is_char_type ("BLANK", dt->blank))
+	return MATCH_ERROR;
+if (dt->blank->expr_type == EXPR_CONSTANT)
+	{
+	  static const char * blank[] = { "NULL", "ZERO", NULL };
+	  if (!compare_to_allowed_values ("BLANK", blank, NULL, NULL,
+					  dt->blank->value.character.string,
+					  io_kind_name (k), warn))
+	    return MATCH_ERROR;
+	  io_constraint (unformatted,
+			 "the BLANK= specifier at %L must be with an "
+			 "explicit format expression", &dt->blank->where);
+	}
+}
+if (dt->pad)
+{
+if (!gfc_notify_std (GFC_STD_F2003, "PAD= at %C "
+			   "not allowed in Fortran 95"))
+	return MATCH_ERROR;
+if (!is_char_type ("PAD", dt->pad))
+	return MATCH_ERROR;
+if (dt->pad->expr_type == EXPR_CONSTANT)
+	{
+	  static const char * pad[] = { "YES", "NO", NULL };
+	  if (!compare_to_allowed_values ("PAD", pad, NULL, NULL,
+					  dt->pad->value.character.string,
+					  io_kind_name (k), warn))
+	    return MATCH_ERROR;
+	  io_constraint (unformatted,
+			 "the PAD= specifier at %L must be with an "
+			 "explicit format expression", &dt->pad->where);
+	}
+}
+if (dt->round)
+{
+if (!gfc_notify_std (GFC_STD_F2003, "ROUND= at %C "
+			   "not allowed in Fortran 95"))
+	return MATCH_ERROR;
+if (!is_char_type ("ROUND", dt->round))
+	return MATCH_ERROR;
+if (dt->round->expr_type == EXPR_CONSTANT)
+	{
+	  static const char * round[] = { "UP", "DOWN", "ZERO", "NEAREST",
+					  "COMPATIBLE", "PROCESSOR_DEFINED",
+					  NULL };
+	  if (!compare_to_allowed_values ("ROUND", round, NULL, NULL,
+					  dt->round->value.character.string,
+					  io_kind_name (k), warn))
+	    return MATCH_ERROR;
+	}
+}
+if (dt->sign)
+{
+/* When implemented, change the following to use gfc_notify_std F2003.
+if (gfc_notify_std (GFC_STD_F2003, "SIGN= at %C "
+	  "not allowed in Fortran 95") == false)
+	return MATCH_ERROR;  */
+if (!is_char_type ("SIGN", dt->sign))
+	return MATCH_ERROR;
+if (dt->sign->expr_type == EXPR_CONSTANT)
+	{
+	  static const char * sign[] = { "PLUS", "SUPPRESS", "PROCESSOR_DEFINED",
+					 NULL };
+	  if (!compare_to_allowed_values ("SIGN", sign, NULL, NULL,
+				      dt->sign->value.character.string,
+				      io_kind_name (k), warn))
+	    return MATCH_ERROR;
+	  io_constraint (unformatted,
+			 "SIGN= specifier at %L must be with an "
+			 "explicit format expression", &dt->sign->where);
+	  io_constraint (k == M_READ,
+			 "SIGN= specifier at %L not allowed in a "
+			 "READ statement", &dt->sign->where);
+	}
+}
+if (dt->delim)
+{
+if (!gfc_notify_std (GFC_STD_F2003, "DELIM= at %C "
+			   "not allowed in Fortran 95"))
+	return MATCH_ERROR;
+if (!is_char_type ("DELIM", dt->delim))
+	return MATCH_ERROR;
+if (dt->delim->expr_type == EXPR_CONSTANT)
+	{
+	  static const char *delim[] = { "APOSTROPHE", "QUOTE", "NONE", NULL };
+	  if (!compare_to_allowed_values ("DELIM", delim, NULL, NULL,
+					  dt->delim->value.character.string,
+					  io_kind_name (k), warn))
+	    return MATCH_ERROR;
+	  io_constraint (k == M_READ,
+			 "DELIM= specifier at %L not allowed in a "
+			 "READ statement", &dt->delim->where);
+	  io_constraint (dt->format_label != &format_asterisk
+			 && dt->namelist == NULL,
+			 "DELIM= specifier at %L must have FMT=*",
+			 &dt->delim->where);
+	  io_constraint (unformatted && dt->namelist == NULL,
+			 "DELIM= specifier at %L must be with FMT=* or "
+			 "NML= specifier", &dt->delim->where);
+	}
+}
+if (dt->namelist)
+{
+io_constraint (io_code && dt->namelist,
+		     "NAMELIST cannot be followed by IO-list at %L",
+		     &io_code->loc);
+io_constraint (dt->format_expr,
+		     "IO spec-list cannot contain both NAMELIST group name "
+		     "and format specification at %L",
+		     &dt->format_expr->where);
+io_constraint (dt->format_label,
+		     "IO spec-list cannot contain both NAMELIST group name "
+		     "and format label at %L", spec_end);
+io_constraint (dt->rec,
+		     "NAMELIST IO is not allowed with a REC= specifier "
+		     "at %L", &dt->rec->where);
+io_constraint (dt->advance,
+		     "NAMELIST IO is not allowed with a ADVANCE= specifier "
+		     "at %L", &dt->advance->where);
+}
+if (dt->rec)
+{
+io_constraint (dt->end,
+		     "An END tag is not allowed with a "
+		     "REC= specifier at %L", &dt->end_where);
+io_constraint (dt->format_label == &format_asterisk,
+		     "FMT=* is not allowed with a REC= specifier "
+		     "at %L", spec_end);
+io_constraint (dt->pos,
+		     "POS= is not allowed with REC= specifier "
+		     "at %L", &dt->pos->where);
+}
+if (dt->advance)
+{
+int not_yes, not_no;
+expr = dt->advance;
+io_constraint (dt->format_label == &format_asterisk,
+		     "List directed format(*) is not allowed with a "
+		     "ADVANCE= specifier at %L.", &expr->where);
+io_constraint (unformatted,
+		     "the ADVANCE= specifier at %L must appear with an "
+		     "explicit format expression", &expr->where);
+if (expr->expr_type == EXPR_CONSTANT && expr->ts.type == BT_CHARACTER)
+	{
+	  const gfc_char_t *advance = expr->value.character.string;
+	  not_no = gfc_wide_strlen (advance) != 2
+		   || gfc_wide_strncasecmp (advance, "no", 2) != 0;
+	  not_yes = gfc_wide_strlen (advance) != 3
+		    || gfc_wide_strncasecmp (advance, "yes", 3) != 0;
+	}
+else
+	{
+	  not_no = 0;
+	  not_yes = 0;
+	}
+io_constraint (not_no && not_yes,
+		     "ADVANCE= specifier at %L must have value = "
+		     "YES or NO.", &expr->where);
+io_constraint (dt->size && not_no && k == M_READ,
+		     "SIZE tag at %L requires an ADVANCE = %<NO%>",
+		     &dt->size->where);
+io_constraint (dt->eor && not_no && k == M_READ,
+		     "EOR tag at %L requires an ADVANCE = %<NO%>",
+		     &dt->eor_where);
+}
+expr = dt->format_expr;
+if (!gfc_simplify_expr (expr, 0)
+|| !check_format_string (expr, k == M_READ))
+return MATCH_ERROR;
+return m;
+}
+#undef io_constraint
+/* Match a READ, WRITE or PRINT statement.  */
+static match
+match_io (io_kind k)
+{
+char name[GFC_MAX_SYMBOL_LEN + 1];
+gfc_code *io_code;
+gfc_symbol *sym;
+int comma_flag;
+locus where;
+locus spec_end, control;
+gfc_dt *dt;
+match m;
+where = gfc_current_locus;
+comma_flag = 0;
+current_dt = dt = XCNEW (gfc_dt);
+m = gfc_match_char ('(');
+if (m == MATCH_NO)
+{
+where = gfc_current_locus;
+if (k == M_WRITE)
+	goto syntax;
+else if (k == M_PRINT)
+	{
+	  /* Treat the non-standard case of PRINT namelist.  */
+	  if ((gfc_current_form == FORM_FIXED || gfc_peek_ascii_char () == ' ')
+	      && gfc_match_name (name) == MATCH_YES)
+	    {
+	      gfc_find_symbol (name, NULL, 1, &sym);
+	      if (sym && sym->attr.flavor == FL_NAMELIST)
+		{
+		  if (!gfc_notify_std (GFC_STD_GNU, "PRINT namelist at "
+				       "%C is an extension"))
+		    {
+		      m = MATCH_ERROR;
+		      goto cleanup;
+		    }
+		  dt->io_unit = default_unit (k);
+		  dt->namelist = sym;
+		  goto get_io_list;
+		}
+	      else
+		gfc_current_locus = where;
+	    }
+	}
+if (gfc_current_form == FORM_FREE)
+	{
+	  char c = gfc_peek_ascii_char ();
+	  if (c != ' ' && c != '*' && c != '\'' && c != '"')
+	    {
+	      m = MATCH_NO;
+	      goto cleanup;
+	    }
+	}
+m = match_dt_format (dt);
+if (m == MATCH_ERROR)
+	goto cleanup;
+if (m == MATCH_NO)
+	goto syntax;
+comma_flag = 1;
+dt->io_unit = default_unit (k);
+goto get_io_list;
+}
+else
+{
+/* Before issuing an error for a malformed 'print (1,*)' type of
+	 error, check for a default-char-expr of the form ('(I0)').  */
+if (m == MATCH_YES)
+{
+	  control = gfc_current_locus;
+	  if (k == M_PRINT)
+	    {
+	      /* Reset current locus to get the initial '(' in an expression.  */
+	      gfc_current_locus = where;
+	      dt->format_expr = NULL;
+	      m = match_dt_format (dt);
+	      if (m == MATCH_ERROR)
+		goto cleanup;
+	      if (m == MATCH_NO || dt->format_expr == NULL)
+		goto syntax;
+	      comma_flag = 1;
+	      dt->io_unit = default_unit (k);
+	      goto get_io_list;
+	    }
+	  if (k == M_READ)
+	    {
+	      /* Commit any pending symbols now so that when we undo
+		 symbols later we wont lose them.  */
+	      gfc_commit_symbols ();
+	      /* Reset current locus to get the initial '(' in an expression.  */
+	      gfc_current_locus = where;
+	      dt->format_expr = NULL;
+	      m = gfc_match_expr (&dt->format_expr);
+	      if (m == MATCH_YES)
+	        {
+		  if (dt->format_expr
+		      && dt->format_expr->ts.type == BT_CHARACTER)
+		    {
+		      comma_flag = 1;
+		      dt->io_unit = default_unit (k);
+		      goto get_io_list;
+		    }
+		  else
+		    {
+		      gfc_free_expr (dt->format_expr);
+		      dt->format_expr = NULL;
+		      gfc_current_locus = control;
+		    }
+		}
+	      else
+	        {
+		  gfc_clear_error ();
+		  gfc_undo_symbols ();
+		  gfc_free_expr (dt->format_expr);
+		  dt->format_expr = NULL;
+		  gfc_current_locus = control;
+		}
+	    }
+	}
+}
+/* Match a control list */
+if (match_dt_element (k, dt) == MATCH_YES)
+goto next;
+if (match_dt_unit (k, dt) != MATCH_YES)
+goto loop;
+if (gfc_match_char (')') == MATCH_YES)
+goto get_io_list;
+if (gfc_match_char (',') != MATCH_YES)
+goto syntax;
+m = match_dt_element (k, dt);
+if (m == MATCH_YES)
+goto next;
+if (m == MATCH_ERROR)
+goto cleanup;
+m = match_dt_format (dt);
+if (m == MATCH_YES)
+goto next;
+if (m == MATCH_ERROR)
+goto cleanup;
+where = gfc_current_locus;
+m = gfc_match_name (name);
+if (m == MATCH_YES)
+{
+gfc_find_symbol (name, NULL, 1, &sym);
+if (sym && sym->attr.flavor == FL_NAMELIST)
+	{
+	  dt->namelist = sym;
+	  if (k == M_READ && check_namelist (sym))
+	    {
+	      m = MATCH_ERROR;
+	      goto cleanup;
+	    }
+	  goto next;
+	}
+}
+gfc_current_locus = where;
+goto loop;			/* No matches, try regular elements */
+next:
+if (gfc_match_char (')') == MATCH_YES)
+goto get_io_list;
+if (gfc_match_char (',') != MATCH_YES)
+goto syntax;
+loop:
+for (;;)
+{
+m = match_dt_element (k, dt);
+if (m == MATCH_NO)
+	goto syntax;
+if (m == MATCH_ERROR)
+	goto cleanup;
+if (gfc_match_char (')') == MATCH_YES)
+	break;
+if (gfc_match_char (',') != MATCH_YES)
+	goto syntax;
+}
+get_io_list:
+/* Used in check_io_constraints, where no locus is available.  */
+spec_end = gfc_current_locus;
+/* Save the IO kind for later use.  */
+dt->dt_io_kind = gfc_get_iokind_expr (&gfc_current_locus, k);
+/* Optional leading comma (non-standard).  We use a gfc_expr structure here
+to save the locus.  This is used later when resolving transfer statements
+that might have a format expression without unit number.  */
+if (!comma_flag && gfc_match_char (',') == MATCH_YES)
+dt->extra_comma = dt->dt_io_kind;
+io_code = NULL;
+if (gfc_match_eos () != MATCH_YES)
+{
+if (comma_flag && gfc_match_char (',') != MATCH_YES)
+	{
+	  gfc_error ("Expected comma in I/O list at %C");
+	  m = MATCH_ERROR;
+	  goto cleanup;
+	}
+m = match_io_list (k, &io_code);
+if (m == MATCH_ERROR)
+	goto cleanup;
+if (m == MATCH_NO)
+	goto syntax;
+}
+/* See if we want to use defaults for missing exponents in real transfers.  */
+if (flag_dec)
+dt->default_exp = 1;
+/* A full IO statement has been matched.  Check the constraints.  spec_end is
+supplied for cases where no locus is supplied.  */
+m = check_io_constraints (k, dt, io_code, &spec_end);
+if (m == MATCH_ERROR)
+goto cleanup;
+new_st.op = (k == M_READ) ? EXEC_READ : EXEC_WRITE;
+new_st.ext.dt = dt;
+new_st.block = gfc_get_code (new_st.op);
+new_st.block->next = io_code;
+terminate_io (io_code);
+return MATCH_YES;
+syntax:
+gfc_error ("Syntax error in %s statement at %C", io_kind_name (k));
+m = MATCH_ERROR;
+cleanup:
+gfc_free_dt (dt);
+return m;
+}
+match
+gfc_match_read (void)
+{
+return match_io (M_READ);
+}
+match
+gfc_match_write (void)
+{
+return match_io (M_WRITE);
+}
+match
+gfc_match_print (void)
+{
+match m;
+m = match_io (M_PRINT);
+if (m != MATCH_YES)
+return m;
+if (gfc_pure (NULL))
+{
+gfc_error ("PRINT statement at %C not allowed within PURE procedure");
+return MATCH_ERROR;
+}
+gfc_unset_implicit_pure (NULL);
+return MATCH_YES;
+}
+/* Free a gfc_inquire structure.  */
+void
+gfc_free_inquire (gfc_inquire *inquire)
+{
+if (inquire == NULL)
+return;
+gfc_free_expr (inquire->unit);
+gfc_free_expr (inquire->file);
+gfc_free_expr (inquire->iomsg);
+gfc_free_expr (inquire->iostat);
+gfc_free_expr (inquire->exist);
+gfc_free_expr (inquire->opened);
+gfc_free_expr (inquire->number);
+gfc_free_expr (inquire->named);
+gfc_free_expr (inquire->name);
+gfc_free_expr (inquire->access);
+gfc_free_expr (inquire->sequential);
+gfc_free_expr (inquire->direct);
+gfc_free_expr (inquire->form);
+gfc_free_expr (inquire->formatted);
+gfc_free_expr (inquire->unformatted);
+gfc_free_expr (inquire->recl);
+gfc_free_expr (inquire->nextrec);
+gfc_free_expr (inquire->blank);
+gfc_free_expr (inquire->position);
+gfc_free_expr (inquire->action);
+gfc_free_expr (inquire->read);
+gfc_free_expr (inquire->write);
+gfc_free_expr (inquire->readwrite);
+gfc_free_expr (inquire->delim);
+gfc_free_expr (inquire->encoding);
+gfc_free_expr (inquire->pad);
+gfc_free_expr (inquire->iolength);
+gfc_free_expr (inquire->convert);
+gfc_free_expr (inquire->strm_pos);
+gfc_free_expr (inquire->asynchronous);
+gfc_free_expr (inquire->decimal);
+gfc_free_expr (inquire->pending);
+gfc_free_expr (inquire->id);
+gfc_free_expr (inquire->sign);
+gfc_free_expr (inquire->size);
+gfc_free_expr (inquire->round);
+gfc_free_expr (inquire->share);
+gfc_free_expr (inquire->cc);
+free (inquire);
+}
+/* Match an element of an INQUIRE statement.  */
+#define RETM   if (m != MATCH_NO) return m;
+static match
+match_inquire_element (gfc_inquire *inquire)
+{
+match m;
+m = match_etag (&tag_unit, &inquire->unit);
+RETM m = match_etag (&tag_file, &inquire->file);
+RETM m = match_ltag (&tag_err, &inquire->err);
+RETM m = match_etag (&tag_iomsg, &inquire->iomsg);
+if (m == MATCH_YES && !check_char_variable (inquire->iomsg))
+return MATCH_ERROR;
+RETM m = match_out_tag (&tag_iostat, &inquire->iostat);
+RETM m = match_vtag (&tag_exist, &inquire->exist);
+RETM m = match_vtag (&tag_opened, &inquire->opened);
+RETM m = match_vtag (&tag_named, &inquire->named);
+RETM m = match_vtag (&tag_name, &inquire->name);
+RETM m = match_out_tag (&tag_number, &inquire->number);
+RETM m = match_vtag (&tag_s_access, &inquire->access);
+RETM m = match_vtag (&tag_sequential, &inquire->sequential);
+RETM m = match_vtag (&tag_direct, &inquire->direct);
+RETM m = match_vtag (&tag_s_form, &inquire->form);
+RETM m = match_vtag (&tag_formatted, &inquire->formatted);
+RETM m = match_vtag (&tag_unformatted, &inquire->unformatted);
+RETM m = match_out_tag (&tag_s_recl, &inquire->recl);
+RETM m = match_out_tag (&tag_nextrec, &inquire->nextrec);
+RETM m = match_vtag (&tag_s_blank, &inquire->blank);
+RETM m = match_vtag (&tag_s_position, &inquire->position);
+RETM m = match_vtag (&tag_s_action, &inquire->action);
+RETM m = match_vtag (&tag_read, &inquire->read);
+RETM m = match_vtag (&tag_write, &inquire->write);
+RETM m = match_vtag (&tag_readwrite, &inquire->readwrite);
+RETM m = match_vtag (&tag_s_async, &inquire->asynchronous);
+if (m == MATCH_YES && !is_char_type ("ASYNCHRONOUS", inquire->asynchronous))
+return MATCH_ERROR;
+RETM m = match_vtag (&tag_s_delim, &inquire->delim);
+RETM m = match_vtag (&tag_s_decimal, &inquire->decimal);
+RETM m = match_out_tag (&tag_size, &inquire->size);
+RETM m = match_vtag (&tag_s_encoding, &inquire->encoding);
+RETM m = match_vtag (&tag_s_round, &inquire->round);
+RETM m = match_vtag (&tag_s_sign, &inquire->sign);
+RETM m = match_vtag (&tag_s_pad, &inquire->pad);
+RETM m = match_out_tag (&tag_iolength, &inquire->iolength);
+RETM m = match_vtag (&tag_convert, &inquire->convert);
+RETM m = match_out_tag (&tag_strm_out, &inquire->strm_pos);
+RETM m = match_vtag (&tag_pending, &inquire->pending);
+RETM m = match_vtag (&tag_id, &inquire->id);
+RETM m = match_vtag (&tag_s_iqstream, &inquire->iqstream);
+RETM m = match_dec_vtag (&tag_v_share, &inquire->share);
+RETM m = match_dec_vtag (&tag_v_cc, &inquire->cc);
+RETM return MATCH_NO;
+}
+#undef RETM
+match
+gfc_match_inquire (void)
+{
+gfc_inquire *inquire;
+gfc_code *code;
+match m;
+locus loc;
+m = gfc_match_char ('(');
+if (m == MATCH_NO)
+return m;
+inquire = XCNEW (gfc_inquire);
+loc = gfc_current_locus;
+m = match_inquire_element (inquire);
+if (m == MATCH_ERROR)
+goto cleanup;
+if (m == MATCH_NO)
+{
+m = gfc_match_expr (&inquire->unit);
+if (m == MATCH_ERROR)
+	goto cleanup;
+if (m == MATCH_NO)
+	goto syntax;
+}
+/* See if we have the IOLENGTH form of the inquire statement.  */
+if (inquire->iolength != NULL)
+{
+if (gfc_match_char (')') != MATCH_YES)
+	goto syntax;
+m = match_io_list (M_INQUIRE, &code);
+if (m == MATCH_ERROR)
+	goto cleanup;
+if (m == MATCH_NO)
+	goto syntax;
+new_st.op = EXEC_IOLENGTH;
+new_st.expr1 = inquire->iolength;
+new_st.ext.inquire = inquire;
+if (gfc_pure (NULL))
+	{
+	  gfc_free_statements (code);
+	  gfc_error ("INQUIRE statement not allowed in PURE procedure at %C");
+	  return MATCH_ERROR;
+	}
+gfc_unset_implicit_pure (NULL);
+new_st.block = gfc_get_code (EXEC_IOLENGTH);
+terminate_io (code);
+new_st.block->next = code;
+return MATCH_YES;
+}
+/* At this point, we have the non-IOLENGTH inquire statement.  */
+for (;;)
+{
+if (gfc_match_char (')') == MATCH_YES)
+	break;
+if (gfc_match_char (',') != MATCH_YES)
+	goto syntax;
+m = match_inquire_element (inquire);
+if (m == MATCH_ERROR)
+	goto cleanup;
+if (m == MATCH_NO)
+	goto syntax;
+if (inquire->iolength != NULL)
+	{
+	  gfc_error ("IOLENGTH tag invalid in INQUIRE statement at %C");
+	  goto cleanup;
+	}
+}
+if (gfc_match_eos () != MATCH_YES)
+goto syntax;
+if (inquire->unit != NULL && inquire->file != NULL)
+{
+gfc_error ("INQUIRE statement at %L cannot contain both FILE and "
+		 "UNIT specifiers", &loc);
+goto cleanup;
+}
+if (inquire->unit == NULL && inquire->file == NULL)
+{
+gfc_error ("INQUIRE statement at %L requires either FILE or "
+		 "UNIT specifier", &loc);
+goto cleanup;
+}
+if (inquire->unit != NULL && inquire->unit->expr_type == EXPR_CONSTANT
+&& inquire->unit->ts.type == BT_INTEGER
+&& ((mpz_get_si (inquire->unit->value.integer) == GFC_INTERNAL_UNIT4)
+|| (mpz_get_si (inquire->unit->value.integer) == GFC_INTERNAL_UNIT)))
+{
+gfc_error ("UNIT number in INQUIRE statement at %L can not "
+		 "be %d", &loc, (int) mpz_get_si (inquire->unit->value.integer));
+goto cleanup;
+}
+if (gfc_pure (NULL))
+{
+gfc_error ("INQUIRE statement not allowed in PURE procedure at %C");
+goto cleanup;
+}
+gfc_unset_implicit_pure (NULL);
+if (inquire->id != NULL && inquire->pending == NULL)
+{
+gfc_error ("INQUIRE statement at %L requires a PENDING= specifier with "
+		 "the ID= specifier", &loc);
+goto cleanup;
+}
+new_st.op = EXEC_INQUIRE;
+new_st.ext.inquire = inquire;
+return MATCH_YES;
+syntax:
+gfc_syntax_error (ST_INQUIRE);
+cleanup:
+gfc_free_inquire (inquire);
+return MATCH_ERROR;
+}
+/* Resolve everything in a gfc_inquire structure.  */
+bool
+gfc_resolve_inquire (gfc_inquire *inquire)
+{
+RESOLVE_TAG (&tag_unit, inquire->unit);
+RESOLVE_TAG (&tag_file, inquire->file);
+RESOLVE_TAG (&tag_id, inquire->id);
+/* For INQUIRE, all tags except FILE, ID and UNIT are variable definition
+contexts.  Thus, use an extended RESOLVE_TAG macro for that.  */
+#define INQUIRE_RESOLVE_TAG(tag, expr) \
+RESOLVE_TAG (tag, expr); \
+if (expr) \
+{ \
+char context[64]; \
+sprintf (context, _("%s tag with INQUIRE"), (tag)->name); \
+if (gfc_check_vardef_context ((expr), false, false, false, \
+				    context) == false) \
+	return false; \
+}
+INQUIRE_RESOLVE_TAG (&tag_iomsg, inquire->iomsg);
+INQUIRE_RESOLVE_TAG (&tag_iostat, inquire->iostat);
+INQUIRE_RESOLVE_TAG (&tag_exist, inquire->exist);
+INQUIRE_RESOLVE_TAG (&tag_opened, inquire->opened);
+INQUIRE_RESOLVE_TAG (&tag_number, inquire->number);
+INQUIRE_RESOLVE_TAG (&tag_named, inquire->named);
+INQUIRE_RESOLVE_TAG (&tag_name, inquire->name);
+INQUIRE_RESOLVE_TAG (&tag_s_access, inquire->access);
+INQUIRE_RESOLVE_TAG (&tag_sequential, inquire->sequential);
+INQUIRE_RESOLVE_TAG (&tag_direct, inquire->direct);
+INQUIRE_RESOLVE_TAG (&tag_s_form, inquire->form);
+INQUIRE_RESOLVE_TAG (&tag_formatted, inquire->formatted);
+INQUIRE_RESOLVE_TAG (&tag_unformatted, inquire->unformatted);
+INQUIRE_RESOLVE_TAG (&tag_s_recl, inquire->recl);
+INQUIRE_RESOLVE_TAG (&tag_nextrec, inquire->nextrec);
+INQUIRE_RESOLVE_TAG (&tag_s_blank, inquire->blank);
+INQUIRE_RESOLVE_TAG (&tag_s_position, inquire->position);
+INQUIRE_RESOLVE_TAG (&tag_s_action, inquire->action);
+INQUIRE_RESOLVE_TAG (&tag_read, inquire->read);
+INQUIRE_RESOLVE_TAG (&tag_write, inquire->write);
+INQUIRE_RESOLVE_TAG (&tag_readwrite, inquire->readwrite);
+INQUIRE_RESOLVE_TAG (&tag_s_delim, inquire->delim);
+INQUIRE_RESOLVE_TAG (&tag_s_pad, inquire->pad);
+INQUIRE_RESOLVE_TAG (&tag_s_encoding, inquire->encoding);
+INQUIRE_RESOLVE_TAG (&tag_s_round, inquire->round);
+INQUIRE_RESOLVE_TAG (&tag_iolength, inquire->iolength);
+INQUIRE_RESOLVE_TAG (&tag_convert, inquire->convert);
+INQUIRE_RESOLVE_TAG (&tag_strm_out, inquire->strm_pos);
+INQUIRE_RESOLVE_TAG (&tag_s_async, inquire->asynchronous);
+INQUIRE_RESOLVE_TAG (&tag_s_sign, inquire->sign);
+INQUIRE_RESOLVE_TAG (&tag_s_round, inquire->round);
+INQUIRE_RESOLVE_TAG (&tag_pending, inquire->pending);
+INQUIRE_RESOLVE_TAG (&tag_size, inquire->size);
+INQUIRE_RESOLVE_TAG (&tag_s_decimal, inquire->decimal);
+INQUIRE_RESOLVE_TAG (&tag_s_iqstream, inquire->iqstream);
+INQUIRE_RESOLVE_TAG (&tag_v_share, inquire->share);
+INQUIRE_RESOLVE_TAG (&tag_v_cc, inquire->cc);
+#undef INQUIRE_RESOLVE_TAG
+if (!gfc_reference_st_label (inquire->err, ST_LABEL_TARGET))
+return false;
+return true;
+}
+void
+gfc_free_wait (gfc_wait *wait)
+{
+if (wait == NULL)
+return;
+gfc_free_expr (wait->unit);
+gfc_free_expr (wait->iostat);
+gfc_free_expr (wait->iomsg);
+gfc_free_expr (wait->id);
+free (wait);
+}
+bool
+gfc_resolve_wait (gfc_wait *wait)
+{
+RESOLVE_TAG (&tag_unit, wait->unit);
+RESOLVE_TAG (&tag_iomsg, wait->iomsg);
+RESOLVE_TAG (&tag_iostat, wait->iostat);
+RESOLVE_TAG (&tag_id, wait->id);
+if (!gfc_reference_st_label (wait->err, ST_LABEL_TARGET))
+return false;
+if (!gfc_reference_st_label (wait->end, ST_LABEL_TARGET))
+return false;
+return true;
+}
+/* Match an element of a WAIT statement.  */
+#define RETM   if (m != MATCH_NO) return m;
+static match
+match_wait_element (gfc_wait *wait)
+{
+match m;
+m = match_etag (&tag_unit, &wait->unit);
+RETM m = match_ltag (&tag_err, &wait->err);
+RETM m = match_ltag (&tag_end, &wait->end);
+RETM m = match_ltag (&tag_eor, &wait->eor);
+RETM m = match_etag (&tag_iomsg, &wait->iomsg);
+if (m == MATCH_YES && !check_char_variable (wait->iomsg))
+return MATCH_ERROR;
+RETM m = match_out_tag (&tag_iostat, &wait->iostat);
+RETM m = match_etag (&tag_id, &wait->id);
+RETM return MATCH_NO;
+}
+#undef RETM
+match
+gfc_match_wait (void)
+{
+gfc_wait *wait;
+match m;
+m = gfc_match_char ('(');
+if (m == MATCH_NO)
+return m;
+wait = XCNEW (gfc_wait);
+m = match_wait_element (wait);
+if (m == MATCH_ERROR)
+goto cleanup;
+if (m == MATCH_NO)
+{
+m = gfc_match_expr (&wait->unit);
+if (m == MATCH_ERROR)
+	goto cleanup;
+if (m == MATCH_NO)
+	goto syntax;
+}
+for (;;)
+{
+if (gfc_match_char (')') == MATCH_YES)
+	break;
+if (gfc_match_char (',') != MATCH_YES)
+	goto syntax;
+m = match_wait_element (wait);
+if (m == MATCH_ERROR)
+	goto cleanup;
+if (m == MATCH_NO)
+	goto syntax;
+}
+if (!gfc_notify_std (GFC_STD_F2003, "WAIT at %C "
+		       "not allowed in Fortran 95"))
+goto cleanup;
+if (gfc_pure (NULL))
+{
+gfc_error ("WAIT statement not allowed in PURE procedure at %C");
+goto cleanup;
+}
+gfc_unset_implicit_pure (NULL);
+new_st.op = EXEC_WAIT;
+new_st.ext.wait = wait;
+return MATCH_YES;
+syntax:
+gfc_syntax_error (ST_WAIT);
+cleanup:
+gfc_free_wait (wait);
+return MATCH_ERROR;
+}

Mercurial > hg > CbC > CbC_gcc

comparison gcc/fortran/io.c @ 111:04ced10e8804