1 /* Primary expression subroutines
2 Copyright (C) 2000, 2001, 2002, 2004, 2005, 2006, 2007
3 Free Software Foundation, Inc.
4 Contributed by Andy Vaught
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
30 /* Matches a kind-parameter expression, which is either a named
31 symbolic constant or a nonnegative integer constant. If
32 successful, sets the kind value to the correct integer. */
35 match_kind_param (int *kind)
37 char name[GFC_MAX_SYMBOL_LEN + 1];
42 m = gfc_match_small_literal_int (kind, NULL);
46 m = gfc_match_name (name);
50 if (gfc_find_symbol (name, NULL, 1, &sym))
56 if (sym->attr.flavor != FL_PARAMETER)
59 p = gfc_extract_int (sym->value, kind);
70 /* Get a trailing kind-specification for non-character variables.
72 the integer kind value or:
73 -1 if an error was generated
74 -2 if no kind was found */
82 if (gfc_match_char ('_') != MATCH_YES)
85 m = match_kind_param (&kind);
87 gfc_error ("Missing kind-parameter at %C");
89 return (m == MATCH_YES) ? kind : -1;
93 /* Given a character and a radix, see if the character is a valid
94 digit in that radix. */
97 check_digit (int c, int radix)
104 r = ('0' <= c && c <= '1');
108 r = ('0' <= c && c <= '7');
112 r = ('0' <= c && c <= '9');
120 gfc_internal_error ("check_digit(): bad radix");
127 /* Match the digit string part of an integer if signflag is not set,
128 the signed digit string part if signflag is set. If the buffer
129 is NULL, we just count characters for the resolution pass. Returns
130 the number of characters matched, -1 for no match. */
133 match_digits (int signflag, int radix, char *buffer)
139 c = gfc_next_char ();
141 if (signflag && (c == '+' || c == '-'))
145 gfc_gobble_whitespace ();
146 c = gfc_next_char ();
150 if (!check_digit (c, radix))
159 old_loc = gfc_current_locus;
160 c = gfc_next_char ();
162 if (!check_digit (c, radix))
170 gfc_current_locus = old_loc;
176 /* Match an integer (digit string and optional kind).
177 A sign will be accepted if signflag is set. */
180 match_integer_constant (gfc_expr **result, int signflag)
187 old_loc = gfc_current_locus;
188 gfc_gobble_whitespace ();
190 length = match_digits (signflag, 10, NULL);
191 gfc_current_locus = old_loc;
195 buffer = alloca (length + 1);
196 memset (buffer, '\0', length + 1);
198 gfc_gobble_whitespace ();
200 match_digits (signflag, 10, buffer);
204 kind = gfc_default_integer_kind;
208 if (gfc_validate_kind (BT_INTEGER, kind, true) < 0)
210 gfc_error ("Integer kind %d at %C not available", kind);
214 e = gfc_convert_integer (buffer, kind, 10, &gfc_current_locus);
216 if (gfc_range_check (e) != ARITH_OK)
218 gfc_error ("Integer too big for its kind at %C. This check can be "
219 "disabled with the option -fno-range-check");
230 /* Match a Hollerith constant. */
233 match_hollerith_constant (gfc_expr **result)
241 old_loc = gfc_current_locus;
242 gfc_gobble_whitespace ();
244 if (match_integer_constant (&e, 0) == MATCH_YES
245 && gfc_match_char ('h') == MATCH_YES)
247 if (gfc_notify_std (GFC_STD_LEGACY, "Extension: Hollerith constant "
251 msg = gfc_extract_int (e, &num);
259 gfc_error ("Invalid Hollerith constant: %L must contain at least "
260 "one character", &old_loc);
263 if (e->ts.kind != gfc_default_integer_kind)
265 gfc_error ("Invalid Hollerith constant: Integer kind at %L "
266 "should be default", &old_loc);
272 e = gfc_constant_result (BT_HOLLERITH, gfc_default_character_kind,
275 e->representation.string = gfc_getmem (num + 1);
276 for (i = 0; i < num; i++)
278 e->representation.string[i] = gfc_next_char_literal (1);
280 e->representation.string[num] = '\0';
281 e->representation.length = num;
289 gfc_current_locus = old_loc;
298 /* Match a binary, octal or hexadecimal constant that can be found in
299 a DATA statement. The standard permits b'010...', o'73...', and
300 z'a1...' where b, o, and z can be capital letters. This function
301 also accepts postfixed forms of the constants: '01...'b, '73...'o,
302 and 'a1...'z. An additional extension is the use of x for z. */
305 match_boz_constant (gfc_expr **result)
307 int post, radix, delim, length, x_hex, kind;
308 locus old_loc, start_loc;
312 start_loc = old_loc = gfc_current_locus;
313 gfc_gobble_whitespace ();
316 switch (post = gfc_next_char ())
338 radix = 16; /* Set to accept any valid digit string. */
344 /* No whitespace allowed here. */
347 delim = gfc_next_char ();
349 if (delim != '\'' && delim != '\"')
352 if (x_hex && pedantic
353 && (gfc_notify_std (GFC_STD_GNU, "Extension: Hexadecimal "
354 "constant at %C uses non-standard syntax.")
358 old_loc = gfc_current_locus;
360 length = match_digits (0, radix, NULL);
363 gfc_error ("Empty set of digits in BOZ constant at %C");
367 if (gfc_next_char () != delim)
369 gfc_error ("Illegal character in BOZ constant at %C");
375 switch (gfc_next_char ())
391 gfc_notify_std (GFC_STD_GNU, "Extension: BOZ constant "
392 "at %C uses non-standard postfix syntax.");
395 gfc_current_locus = old_loc;
397 buffer = alloca (length + 1);
398 memset (buffer, '\0', length + 1);
400 match_digits (0, radix, buffer);
401 gfc_next_char (); /* Eat delimiter. */
403 gfc_next_char (); /* Eat postfixed b, o, z, or x. */
405 /* In section 5.2.5 and following C567 in the Fortran 2003 standard, we find
406 "If a data-stmt-constant is a boz-literal-constant, the corresponding
407 variable shall be of type integer. The boz-literal-constant is treated
408 as if it were an int-literal-constant with a kind-param that specifies
409 the representation method with the largest decimal exponent range
410 supported by the processor." */
412 kind = gfc_max_integer_kind;
413 e = gfc_convert_integer (buffer, kind, radix, &gfc_current_locus);
415 if (gfc_range_check (e) != ARITH_OK)
417 gfc_error ("Integer too big for integer kind %i at %C", kind);
426 gfc_current_locus = start_loc;
431 /* Match a real constant of some sort. Allow a signed constant if signflag
432 is nonzero. Allow integer constants if allow_int is true. */
435 match_real_constant (gfc_expr **result, int signflag)
437 int kind, c, count, seen_dp, seen_digits, exp_char;
438 locus old_loc, temp_loc;
443 old_loc = gfc_current_locus;
444 gfc_gobble_whitespace ();
454 c = gfc_next_char ();
455 if (signflag && (c == '+' || c == '-'))
460 gfc_gobble_whitespace ();
461 c = gfc_next_char ();
464 /* Scan significand. */
465 for (;; c = gfc_next_char (), count++)
472 /* Check to see if "." goes with a following operator like
474 temp_loc = gfc_current_locus;
475 c = gfc_next_char ();
477 if (c == 'e' || c == 'd' || c == 'q')
479 c = gfc_next_char ();
481 goto done; /* Operator named .e. or .d. */
485 goto done; /* Distinguish 1.e9 from 1.eq.2 */
487 gfc_current_locus = temp_loc;
501 if (!seen_digits || (c != 'e' && c != 'd' && c != 'q'))
506 c = gfc_next_char ();
509 if (c == '+' || c == '-')
510 { /* optional sign */
511 c = gfc_next_char ();
517 gfc_error ("Missing exponent in real number at %C");
523 c = gfc_next_char ();
528 /* Check that we have a numeric constant. */
529 if (!seen_digits || (!seen_dp && exp_char == ' '))
531 gfc_current_locus = old_loc;
535 /* Convert the number. */
536 gfc_current_locus = old_loc;
537 gfc_gobble_whitespace ();
539 buffer = alloca (count + 1);
540 memset (buffer, '\0', count + 1);
543 c = gfc_next_char ();
544 if (c == '+' || c == '-')
546 gfc_gobble_whitespace ();
547 c = gfc_next_char ();
550 /* Hack for mpfr_set_str(). */
553 if (c == 'd' || c == 'q')
561 c = gfc_next_char ();
573 gfc_error ("Real number at %C has a 'd' exponent and an explicit "
577 kind = gfc_default_double_kind;
582 kind = gfc_default_real_kind;
584 if (gfc_validate_kind (BT_REAL, kind, true) < 0)
586 gfc_error ("Invalid real kind %d at %C", kind);
591 e = gfc_convert_real (buffer, kind, &gfc_current_locus);
593 mpfr_neg (e->value.real, e->value.real, GFC_RND_MODE);
595 switch (gfc_range_check (e))
600 gfc_error ("Real constant overflows its kind at %C");
603 case ARITH_UNDERFLOW:
604 if (gfc_option.warn_underflow)
605 gfc_warning ("Real constant underflows its kind at %C");
606 mpfr_set_ui (e->value.real, 0, GFC_RND_MODE);
610 gfc_internal_error ("gfc_range_check() returned bad value");
622 /* Match a substring reference. */
625 match_substring (gfc_charlen *cl, int init, gfc_ref **result)
627 gfc_expr *start, *end;
635 old_loc = gfc_current_locus;
637 m = gfc_match_char ('(');
641 if (gfc_match_char (':') != MATCH_YES)
644 m = gfc_match_init_expr (&start);
646 m = gfc_match_expr (&start);
654 m = gfc_match_char (':');
659 if (gfc_match_char (')') != MATCH_YES)
662 m = gfc_match_init_expr (&end);
664 m = gfc_match_expr (&end);
668 if (m == MATCH_ERROR)
671 m = gfc_match_char (')');
676 /* Optimize away the (:) reference. */
677 if (start == NULL && end == NULL)
681 ref = gfc_get_ref ();
683 ref->type = REF_SUBSTRING;
685 start = gfc_int_expr (1);
686 ref->u.ss.start = start;
687 if (end == NULL && cl)
688 end = gfc_copy_expr (cl->length);
690 ref->u.ss.length = cl;
697 gfc_error ("Syntax error in SUBSTRING specification at %C");
701 gfc_free_expr (start);
704 gfc_current_locus = old_loc;
709 /* Reads the next character of a string constant, taking care to
710 return doubled delimiters on the input as a single instance of
713 Special return values are:
714 -1 End of the string, as determined by the delimiter
715 -2 Unterminated string detected
717 Backslash codes are also expanded at this time. */
720 next_string_char (char delimiter)
725 c = gfc_next_char_literal (1);
730 if (gfc_option.flag_backslash && c == '\\')
732 old_locus = gfc_current_locus;
734 if (gfc_match_special_char (&c) == MATCH_NO)
735 gfc_current_locus = old_locus;
737 if (!(gfc_option.allow_std & GFC_STD_GNU) && !inhibit_warnings)
738 gfc_warning ("Extension: backslash character at %C");
744 old_locus = gfc_current_locus;
745 c = gfc_next_char_literal (0);
749 gfc_current_locus = old_locus;
755 /* Special case of gfc_match_name() that matches a parameter kind name
756 before a string constant. This takes case of the weird but legal
761 where kind____ is a parameter. gfc_match_name() will happily slurp
762 up all the underscores, which leads to problems. If we return
763 MATCH_YES, the parse pointer points to the final underscore, which
764 is not part of the name. We never return MATCH_ERROR-- errors in
765 the name will be detected later. */
768 match_charkind_name (char *name)
774 gfc_gobble_whitespace ();
775 c = gfc_next_char ();
784 old_loc = gfc_current_locus;
785 c = gfc_next_char ();
789 peek = gfc_peek_char ();
791 if (peek == '\'' || peek == '\"')
793 gfc_current_locus = old_loc;
801 && (gfc_option.flag_dollar_ok && c != '$'))
805 if (++len > GFC_MAX_SYMBOL_LEN)
813 /* See if the current input matches a character constant. Lots of
814 contortions have to be done to match the kind parameter which comes
815 before the actual string. The main consideration is that we don't
816 want to error out too quickly. For example, we don't actually do
817 any validation of the kinds until we have actually seen a legal
818 delimiter. Using match_kind_param() generates errors too quickly. */
821 match_string_constant (gfc_expr **result)
823 char *p, name[GFC_MAX_SYMBOL_LEN + 1];
824 int i, c, kind, length, delimiter, warn_ampersand;
825 locus old_locus, start_locus;
831 old_locus = gfc_current_locus;
833 gfc_gobble_whitespace ();
835 start_locus = gfc_current_locus;
837 c = gfc_next_char ();
838 if (c == '\'' || c == '"')
840 kind = gfc_default_character_kind;
850 kind = kind * 10 + c - '0';
853 c = gfc_next_char ();
859 gfc_current_locus = old_locus;
861 m = match_charkind_name (name);
865 if (gfc_find_symbol (name, NULL, 1, &sym)
867 || sym->attr.flavor != FL_PARAMETER)
871 c = gfc_next_char ();
876 gfc_gobble_whitespace ();
877 c = gfc_next_char ();
883 gfc_gobble_whitespace ();
884 start_locus = gfc_current_locus;
886 c = gfc_next_char ();
887 if (c != '\'' && c != '"')
892 q = gfc_extract_int (sym->value, &kind);
900 if (gfc_validate_kind (BT_CHARACTER, kind, true) < 0)
902 gfc_error ("Invalid kind %d for CHARACTER constant at %C", kind);
907 /* Scan the string into a block of memory by first figuring out how
908 long it is, allocating the structure, then re-reading it. This
909 isn't particularly efficient, but string constants aren't that
910 common in most code. TODO: Use obstacks? */
917 c = next_string_char (delimiter);
922 gfc_current_locus = start_locus;
923 gfc_error ("Unterminated character constant beginning at %C");
930 /* Peek at the next character to see if it is a b, o, z, or x for the
931 postfixed BOZ literal constants. */
932 c = gfc_peek_char ();
933 if (c == 'b' || c == 'o' || c =='z' || c == 'x')
939 e->expr_type = EXPR_CONSTANT;
941 e->ts.type = BT_CHARACTER;
943 e->ts.is_c_interop = 0;
945 e->where = start_locus;
947 e->value.character.string = p = gfc_getmem (length + 1);
948 e->value.character.length = length;
950 gfc_current_locus = start_locus;
951 gfc_next_char (); /* Skip delimiter */
953 /* We disable the warning for the following loop as the warning has already
954 been printed in the loop above. */
955 warn_ampersand = gfc_option.warn_ampersand;
956 gfc_option.warn_ampersand = 0;
958 for (i = 0; i < length; i++)
959 *p++ = next_string_char (delimiter);
961 *p = '\0'; /* TODO: C-style string is for development/debug purposes. */
962 gfc_option.warn_ampersand = warn_ampersand;
964 if (next_string_char (delimiter) != -1)
965 gfc_internal_error ("match_string_constant(): Delimiter not found");
967 if (match_substring (NULL, 0, &e->ref) != MATCH_NO)
968 e->expr_type = EXPR_SUBSTRING;
975 gfc_current_locus = old_locus;
980 /* Match a .true. or .false. Returns 1 if a .true. was found,
981 0 if a .false. was found, and -1 otherwise. */
983 match_logical_constant_string (void)
985 locus orig_loc = gfc_current_locus;
987 gfc_gobble_whitespace ();
988 if (gfc_next_char () == '.')
990 int ch = gfc_next_char();
993 if (gfc_next_char () == 'a'
994 && gfc_next_char () == 'l'
995 && gfc_next_char () == 's'
996 && gfc_next_char () == 'e'
997 && gfc_next_char () == '.')
998 /* Matched ".false.". */
1003 if (gfc_next_char () == 'r'
1004 && gfc_next_char () == 'u'
1005 && gfc_next_char () == 'e'
1006 && gfc_next_char () == '.')
1007 /* Matched ".true.". */
1011 gfc_current_locus = orig_loc;
1015 /* Match a .true. or .false. */
1018 match_logical_constant (gfc_expr **result)
1023 i = match_logical_constant_string ();
1031 kind = gfc_default_logical_kind;
1033 if (gfc_validate_kind (BT_LOGICAL, kind, true) < 0)
1035 gfc_error ("Bad kind for logical constant at %C");
1039 e = gfc_get_expr ();
1041 e->expr_type = EXPR_CONSTANT;
1042 e->value.logical = i;
1043 e->ts.type = BT_LOGICAL;
1045 e->ts.is_c_interop = 0;
1047 e->where = gfc_current_locus;
1054 /* Match a real or imaginary part of a complex constant that is a
1055 symbolic constant. */
1058 match_sym_complex_part (gfc_expr **result)
1060 char name[GFC_MAX_SYMBOL_LEN + 1];
1065 m = gfc_match_name (name);
1069 if (gfc_find_symbol (name, NULL, 1, &sym) || sym == NULL)
1072 if (sym->attr.flavor != FL_PARAMETER)
1074 gfc_error ("Expected PARAMETER symbol in complex constant at %C");
1078 if (!gfc_numeric_ts (&sym->value->ts))
1080 gfc_error ("Numeric PARAMETER required in complex constant at %C");
1084 if (sym->value->rank != 0)
1086 gfc_error ("Scalar PARAMETER required in complex constant at %C");
1090 if (gfc_notify_std (GFC_STD_F2003, "Fortran 2003: PARAMETER symbol in "
1091 "complex constant at %C") == FAILURE)
1094 switch (sym->value->ts.type)
1097 e = gfc_copy_expr (sym->value);
1101 e = gfc_complex2real (sym->value, sym->value->ts.kind);
1107 e = gfc_int2real (sym->value, gfc_default_real_kind);
1113 gfc_internal_error ("gfc_match_sym_complex_part(): Bad type");
1116 *result = e; /* e is a scalar, real, constant expression. */
1120 gfc_error ("Error converting PARAMETER constant in complex constant at %C");
1125 /* Match a real or imaginary part of a complex number. */
1128 match_complex_part (gfc_expr **result)
1132 m = match_sym_complex_part (result);
1136 m = match_real_constant (result, 1);
1140 return match_integer_constant (result, 1);
1144 /* Try to match a complex constant. */
1147 match_complex_constant (gfc_expr **result)
1149 gfc_expr *e, *real, *imag;
1150 gfc_error_buf old_error;
1151 gfc_typespec target;
1156 old_loc = gfc_current_locus;
1157 real = imag = e = NULL;
1159 m = gfc_match_char ('(');
1163 gfc_push_error (&old_error);
1165 m = match_complex_part (&real);
1168 gfc_free_error (&old_error);
1172 if (gfc_match_char (',') == MATCH_NO)
1174 gfc_pop_error (&old_error);
1179 /* If m is error, then something was wrong with the real part and we
1180 assume we have a complex constant because we've seen the ','. An
1181 ambiguous case here is the start of an iterator list of some
1182 sort. These sort of lists are matched prior to coming here. */
1184 if (m == MATCH_ERROR)
1186 gfc_free_error (&old_error);
1189 gfc_pop_error (&old_error);
1191 m = match_complex_part (&imag);
1194 if (m == MATCH_ERROR)
1197 m = gfc_match_char (')');
1200 /* Give the matcher for implied do-loops a chance to run. This
1201 yields a much saner error message for (/ (i, 4=i, 6) /). */
1202 if (gfc_peek_char () == '=')
1211 if (m == MATCH_ERROR)
1214 /* Decide on the kind of this complex number. */
1215 if (real->ts.type == BT_REAL)
1217 if (imag->ts.type == BT_REAL)
1218 kind = gfc_kind_max (real, imag);
1220 kind = real->ts.kind;
1224 if (imag->ts.type == BT_REAL)
1225 kind = imag->ts.kind;
1227 kind = gfc_default_real_kind;
1229 target.type = BT_REAL;
1231 target.is_c_interop = 0;
1232 target.is_iso_c = 0;
1234 if (real->ts.type != BT_REAL || kind != real->ts.kind)
1235 gfc_convert_type (real, &target, 2);
1236 if (imag->ts.type != BT_REAL || kind != imag->ts.kind)
1237 gfc_convert_type (imag, &target, 2);
1239 e = gfc_convert_complex (real, imag, kind);
1240 e->where = gfc_current_locus;
1242 gfc_free_expr (real);
1243 gfc_free_expr (imag);
1249 gfc_error ("Syntax error in COMPLEX constant at %C");
1254 gfc_free_expr (real);
1255 gfc_free_expr (imag);
1256 gfc_current_locus = old_loc;
1262 /* Match constants in any of several forms. Returns nonzero for a
1263 match, zero for no match. */
1266 gfc_match_literal_constant (gfc_expr **result, int signflag)
1270 m = match_complex_constant (result);
1274 m = match_string_constant (result);
1278 m = match_boz_constant (result);
1282 m = match_real_constant (result, signflag);
1286 m = match_hollerith_constant (result);
1290 m = match_integer_constant (result, signflag);
1294 m = match_logical_constant (result);
1302 /* Match a single actual argument value. An actual argument is
1303 usually an expression, but can also be a procedure name. If the
1304 argument is a single name, it is not always possible to tell
1305 whether the name is a dummy procedure or not. We treat these cases
1306 by creating an argument that looks like a dummy procedure and
1307 fixing things later during resolution. */
1310 match_actual_arg (gfc_expr **result)
1312 char name[GFC_MAX_SYMBOL_LEN + 1];
1313 gfc_symtree *symtree;
1318 where = gfc_current_locus;
1320 switch (gfc_match_name (name))
1329 w = gfc_current_locus;
1330 gfc_gobble_whitespace ();
1331 c = gfc_next_char ();
1332 gfc_current_locus = w;
1334 if (c != ',' && c != ')')
1337 if (gfc_find_sym_tree (name, NULL, 1, &symtree))
1339 /* Handle error elsewhere. */
1341 /* Eliminate a couple of common cases where we know we don't
1342 have a function argument. */
1343 if (symtree == NULL)
1345 gfc_get_sym_tree (name, NULL, &symtree);
1346 gfc_set_sym_referenced (symtree->n.sym);
1352 sym = symtree->n.sym;
1353 gfc_set_sym_referenced (sym);
1354 if (sym->attr.flavor != FL_PROCEDURE
1355 && sym->attr.flavor != FL_UNKNOWN)
1358 /* If the symbol is a function with itself as the result and
1359 is being defined, then we have a variable. */
1360 if (sym->attr.function && sym->result == sym)
1362 if (gfc_current_ns->proc_name == sym
1363 || (gfc_current_ns->parent != NULL
1364 && gfc_current_ns->parent->proc_name == sym))
1368 && (sym->ns == gfc_current_ns
1369 || sym->ns == gfc_current_ns->parent))
1371 gfc_entry_list *el = NULL;
1373 for (el = sym->ns->entries; el; el = el->next)
1383 e = gfc_get_expr (); /* Leave it unknown for now */
1384 e->symtree = symtree;
1385 e->expr_type = EXPR_VARIABLE;
1386 e->ts.type = BT_PROCEDURE;
1393 gfc_current_locus = where;
1394 return gfc_match_expr (result);
1398 /* Match a keyword argument. */
1401 match_keyword_arg (gfc_actual_arglist *actual, gfc_actual_arglist *base)
1403 char name[GFC_MAX_SYMBOL_LEN + 1];
1404 gfc_actual_arglist *a;
1408 name_locus = gfc_current_locus;
1409 m = gfc_match_name (name);
1413 if (gfc_match_char ('=') != MATCH_YES)
1419 m = match_actual_arg (&actual->expr);
1423 /* Make sure this name has not appeared yet. */
1425 if (name[0] != '\0')
1427 for (a = base; a; a = a->next)
1428 if (a->name != NULL && strcmp (a->name, name) == 0)
1430 gfc_error ("Keyword '%s' at %C has already appeared in the "
1431 "current argument list", name);
1436 actual->name = gfc_get_string (name);
1440 gfc_current_locus = name_locus;
1445 /* Match an argument list function, such as %VAL. */
1448 match_arg_list_function (gfc_actual_arglist *result)
1450 char name[GFC_MAX_SYMBOL_LEN + 1];
1454 old_locus = gfc_current_locus;
1456 if (gfc_match_char ('%') != MATCH_YES)
1462 m = gfc_match ("%n (", name);
1466 if (name[0] != '\0')
1471 if (strncmp (name, "loc", 3) == 0)
1473 result->name = "%LOC";
1477 if (strncmp (name, "ref", 3) == 0)
1479 result->name = "%REF";
1483 if (strncmp (name, "val", 3) == 0)
1485 result->name = "%VAL";
1494 if (gfc_notify_std (GFC_STD_GNU, "Extension: argument list "
1495 "function at %C") == FAILURE)
1501 m = match_actual_arg (&result->expr);
1505 if (gfc_match_char (')') != MATCH_YES)
1514 gfc_current_locus = old_locus;
1519 /* Matches an actual argument list of a function or subroutine, from
1520 the opening parenthesis to the closing parenthesis. The argument
1521 list is assumed to allow keyword arguments because we don't know if
1522 the symbol associated with the procedure has an implicit interface
1523 or not. We make sure keywords are unique. If sub_flag is set,
1524 we're matching the argument list of a subroutine. */
1527 gfc_match_actual_arglist (int sub_flag, gfc_actual_arglist **argp)
1529 gfc_actual_arglist *head, *tail;
1531 gfc_st_label *label;
1535 *argp = tail = NULL;
1536 old_loc = gfc_current_locus;
1540 if (gfc_match_char ('(') == MATCH_NO)
1541 return (sub_flag) ? MATCH_YES : MATCH_NO;
1543 if (gfc_match_char (')') == MATCH_YES)
1550 head = tail = gfc_get_actual_arglist ();
1553 tail->next = gfc_get_actual_arglist ();
1557 if (sub_flag && gfc_match_char ('*') == MATCH_YES)
1559 m = gfc_match_st_label (&label);
1561 gfc_error ("Expected alternate return label at %C");
1565 tail->label = label;
1569 /* After the first keyword argument is seen, the following
1570 arguments must also have keywords. */
1573 m = match_keyword_arg (tail, head);
1575 if (m == MATCH_ERROR)
1579 gfc_error ("Missing keyword name in actual argument list at %C");
1586 /* Try an argument list function, like %VAL. */
1587 m = match_arg_list_function (tail);
1588 if (m == MATCH_ERROR)
1591 /* See if we have the first keyword argument. */
1594 m = match_keyword_arg (tail, head);
1597 if (m == MATCH_ERROR)
1603 /* Try for a non-keyword argument. */
1604 m = match_actual_arg (&tail->expr);
1605 if (m == MATCH_ERROR)
1614 if (gfc_match_char (')') == MATCH_YES)
1616 if (gfc_match_char (',') != MATCH_YES)
1624 gfc_error ("Syntax error in argument list at %C");
1627 gfc_free_actual_arglist (head);
1628 gfc_current_locus = old_loc;
1634 /* Used by match_varspec() to extend the reference list by one
1638 extend_ref (gfc_expr *primary, gfc_ref *tail)
1640 if (primary->ref == NULL)
1641 primary->ref = tail = gfc_get_ref ();
1645 gfc_internal_error ("extend_ref(): Bad tail");
1646 tail->next = gfc_get_ref ();
1654 /* Match any additional specifications associated with the current
1655 variable like member references or substrings. If equiv_flag is
1656 set we only match stuff that is allowed inside an EQUIVALENCE
1660 match_varspec (gfc_expr *primary, int equiv_flag)
1662 char name[GFC_MAX_SYMBOL_LEN + 1];
1663 gfc_ref *substring, *tail;
1664 gfc_component *component;
1665 gfc_symbol *sym = primary->symtree->n.sym;
1670 if ((equiv_flag && gfc_peek_char () == '(') || sym->attr.dimension)
1672 /* In EQUIVALENCE, we don't know yet whether we are seeing
1673 an array, character variable or array of character
1674 variables. We'll leave the decision till resolve time. */
1675 tail = extend_ref (primary, tail);
1676 tail->type = REF_ARRAY;
1678 m = gfc_match_array_ref (&tail->u.ar, equiv_flag ? NULL : sym->as,
1683 if (equiv_flag && gfc_peek_char () == '(')
1685 tail = extend_ref (primary, tail);
1686 tail->type = REF_ARRAY;
1688 m = gfc_match_array_ref (&tail->u.ar, NULL, equiv_flag);
1694 primary->ts = sym->ts;
1699 if (sym->ts.type != BT_DERIVED || gfc_match_char ('%') != MATCH_YES)
1700 goto check_substring;
1702 sym = sym->ts.derived;
1706 m = gfc_match_name (name);
1708 gfc_error ("Expected structure component name at %C");
1712 component = gfc_find_component (sym, name);
1713 if (component == NULL)
1716 tail = extend_ref (primary, tail);
1717 tail->type = REF_COMPONENT;
1719 tail->u.c.component = component;
1720 tail->u.c.sym = sym;
1722 primary->ts = component->ts;
1724 if (component->as != NULL)
1726 tail = extend_ref (primary, tail);
1727 tail->type = REF_ARRAY;
1729 m = gfc_match_array_ref (&tail->u.ar, component->as, equiv_flag);
1734 if (component->ts.type != BT_DERIVED
1735 || gfc_match_char ('%') != MATCH_YES)
1738 sym = component->ts.derived;
1742 if (primary->ts.type == BT_UNKNOWN)
1744 if (gfc_get_default_type (sym, sym->ns)->type == BT_CHARACTER)
1746 gfc_set_default_type (sym, 0, sym->ns);
1747 primary->ts = sym->ts;
1751 if (primary->ts.type == BT_CHARACTER)
1753 switch (match_substring (primary->ts.cl, equiv_flag, &substring))
1757 primary->ref = substring;
1759 tail->next = substring;
1761 if (primary->expr_type == EXPR_CONSTANT)
1762 primary->expr_type = EXPR_SUBSTRING;
1765 primary->ts.cl = NULL;
1781 /* Given an expression that is a variable, figure out what the
1782 ultimate variable's type and attribute is, traversing the reference
1783 structures if necessary.
1785 This subroutine is trickier than it looks. We start at the base
1786 symbol and store the attribute. Component references load a
1787 completely new attribute.
1789 A couple of rules come into play. Subobjects of targets are always
1790 targets themselves. If we see a component that goes through a
1791 pointer, then the expression must also be a target, since the
1792 pointer is associated with something (if it isn't core will soon be
1793 dumped). If we see a full part or section of an array, the
1794 expression is also an array.
1796 We can have at most one full array reference. */
1799 gfc_variable_attr (gfc_expr *expr, gfc_typespec *ts)
1801 int dimension, pointer, allocatable, target;
1802 symbol_attribute attr;
1805 if (expr->expr_type != EXPR_VARIABLE)
1806 gfc_internal_error ("gfc_variable_attr(): Expression isn't a variable");
1809 attr = expr->symtree->n.sym->attr;
1811 dimension = attr.dimension;
1812 pointer = attr.pointer;
1813 allocatable = attr.allocatable;
1815 target = attr.target;
1819 if (ts != NULL && expr->ts.type == BT_UNKNOWN)
1820 *ts = expr->symtree->n.sym->ts;
1822 for (; ref; ref = ref->next)
1827 switch (ref->u.ar.type)
1834 allocatable = pointer = 0;
1839 allocatable = pointer = 0;
1843 gfc_internal_error ("gfc_variable_attr(): Bad array reference");
1849 gfc_get_component_attr (&attr, ref->u.c.component);
1852 *ts = ref->u.c.component->ts;
1853 /* Don't set the string length if a substring reference
1855 if (ts->type == BT_CHARACTER
1856 && ref->next && ref->next->type == REF_SUBSTRING)
1860 pointer = ref->u.c.component->pointer;
1861 allocatable = ref->u.c.component->allocatable;
1868 allocatable = pointer = 0;
1872 attr.dimension = dimension;
1873 attr.pointer = pointer;
1874 attr.allocatable = allocatable;
1875 attr.target = target;
1881 /* Return the attribute from a general expression. */
1884 gfc_expr_attr (gfc_expr *e)
1886 symbol_attribute attr;
1888 switch (e->expr_type)
1891 attr = gfc_variable_attr (e, NULL);
1895 gfc_clear_attr (&attr);
1897 if (e->value.function.esym != NULL)
1898 attr = e->value.function.esym->result->attr;
1900 /* TODO: NULL() returns pointers. May have to take care of this
1906 gfc_clear_attr (&attr);
1914 /* Match a structure constructor. The initial symbol has already been
1918 gfc_match_structure_constructor (gfc_symbol *sym, gfc_expr **result)
1920 gfc_constructor *head, *tail;
1921 gfc_component *comp;
1925 bool private_comp = false;
1929 if (gfc_match_char ('(') != MATCH_YES)
1932 where = gfc_current_locus;
1934 gfc_find_component (sym, NULL);
1936 for (comp = sym->components; comp; comp = comp->next)
1938 if (comp->access == ACCESS_PRIVATE)
1940 private_comp = true;
1944 tail = head = gfc_get_constructor ();
1947 tail->next = gfc_get_constructor ();
1951 m = gfc_match_expr (&tail->expr);
1954 if (m == MATCH_ERROR)
1957 if (gfc_match_char (',') == MATCH_YES)
1959 if (comp->next == NULL)
1961 gfc_error ("Too many components in structure constructor at %C");
1971 if (sym->attr.use_assoc
1972 && (sym->component_access == ACCESS_PRIVATE || private_comp))
1974 gfc_error ("Structure constructor for '%s' at %C has PRIVATE "
1975 "components", sym->name);
1979 if (gfc_match_char (')') != MATCH_YES)
1982 if (comp->next != NULL)
1984 gfc_error ("Too few components in structure constructor at %C");
1988 e = gfc_get_expr ();
1990 e->expr_type = EXPR_STRUCTURE;
1992 e->ts.type = BT_DERIVED;
1993 e->ts.derived = sym;
1996 e->value.constructor = head;
2002 gfc_error ("Syntax error in structure constructor at %C");
2005 gfc_free_constructor (head);
2010 /* If the symbol is an implicit do loop index and implicitly typed,
2011 it should not be host associated. Provide a symtree from the
2012 current namespace. */
2014 check_for_implicit_index (gfc_symtree **st, gfc_symbol **sym)
2016 if ((*sym)->attr.flavor == FL_VARIABLE
2017 && (*sym)->ns != gfc_current_ns
2018 && (*sym)->attr.implied_index
2019 && (*sym)->attr.implicit_type
2020 && !(*sym)->attr.use_assoc)
2023 i = gfc_get_sym_tree ((*sym)->name, NULL, st);
2026 *sym = (*st)->n.sym;
2032 /* Matches a variable name followed by anything that might follow it--
2033 array reference, argument list of a function, etc. */
2036 gfc_match_rvalue (gfc_expr **result)
2038 gfc_actual_arglist *actual_arglist;
2039 char name[GFC_MAX_SYMBOL_LEN + 1], argname[GFC_MAX_SYMBOL_LEN + 1];
2042 gfc_symtree *symtree;
2043 locus where, old_loc;
2051 m = gfc_match_name (name);
2055 if (gfc_find_state (COMP_INTERFACE) == SUCCESS
2056 && !gfc_current_ns->has_import_set)
2057 i = gfc_get_sym_tree (name, NULL, &symtree);
2059 i = gfc_get_ha_sym_tree (name, &symtree);
2064 sym = symtree->n.sym;
2066 where = gfc_current_locus;
2068 /* If this is an implicit do loop index and implicitly typed,
2069 it should not be host associated. */
2070 m = check_for_implicit_index (&symtree, &sym);
2074 gfc_set_sym_referenced (sym);
2075 sym->attr.implied_index = 0;
2077 if (sym->attr.function && sym->result == sym)
2079 /* See if this is a directly recursive function call. */
2080 gfc_gobble_whitespace ();
2081 if (sym->attr.recursive
2082 && gfc_peek_char () == '('
2083 && gfc_current_ns->proc_name == sym
2084 && !sym->attr.dimension)
2086 gfc_error ("'%s' at %C is the name of a recursive function "
2087 "and so refers to the result variable. Use an "
2088 "explicit RESULT variable for direct recursion "
2089 "(12.5.2.1)", sym->name);
2093 if (gfc_current_ns->proc_name == sym
2094 || (gfc_current_ns->parent != NULL
2095 && gfc_current_ns->parent->proc_name == sym))
2099 && (sym->ns == gfc_current_ns
2100 || sym->ns == gfc_current_ns->parent))
2102 gfc_entry_list *el = NULL;
2104 for (el = sym->ns->entries; el; el = el->next)
2110 if (sym->attr.function || sym->attr.external || sym->attr.intrinsic)
2113 if (sym->attr.generic)
2114 goto generic_function;
2116 switch (sym->attr.flavor)
2120 if (sym->ts.type == BT_UNKNOWN && gfc_peek_char () == '%'
2121 && gfc_get_default_type (sym, sym->ns)->type == BT_DERIVED)
2122 gfc_set_default_type (sym, 0, sym->ns);
2124 e = gfc_get_expr ();
2126 e->expr_type = EXPR_VARIABLE;
2127 e->symtree = symtree;
2129 m = match_varspec (e, 0);
2133 /* A statement of the form "REAL, parameter :: a(0:10) = 1" will
2134 end up here. Unfortunately, sym->value->expr_type is set to
2135 EXPR_CONSTANT, and so the if () branch would be followed without
2136 the !sym->as check. */
2137 if (sym->value && sym->value->expr_type != EXPR_ARRAY && !sym->as)
2138 e = gfc_copy_expr (sym->value);
2141 e = gfc_get_expr ();
2142 e->expr_type = EXPR_VARIABLE;
2145 e->symtree = symtree;
2146 m = match_varspec (e, 0);
2148 if (sym->ts.is_c_interop || sym->ts.is_iso_c)
2151 /* Variable array references to derived type parameters cause
2152 all sorts of headaches in simplification. Treating such
2153 expressions as variable works just fine for all array
2155 if (sym->value && sym->ts.type == BT_DERIVED && e->ref)
2157 for (ref = e->ref; ref; ref = ref->next)
2158 if (ref->type == REF_ARRAY)
2161 if (ref == NULL || ref->u.ar.type == AR_FULL)
2167 e = gfc_get_expr ();
2168 e->expr_type = EXPR_VARIABLE;
2169 e->symtree = symtree;
2176 sym = gfc_use_derived (sym);
2180 m = gfc_match_structure_constructor (sym, &e);
2183 /* If we're here, then the name is known to be the name of a
2184 procedure, yet it is not sure to be the name of a function. */
2186 if (sym->attr.subroutine)
2188 gfc_error ("Unexpected use of subroutine name '%s' at %C",
2194 /* At this point, the name has to be a non-statement function.
2195 If the name is the same as the current function being
2196 compiled, then we have a variable reference (to the function
2197 result) if the name is non-recursive. */
2199 st = gfc_enclosing_unit (NULL);
2201 if (st != NULL && st->state == COMP_FUNCTION
2203 && !sym->attr.recursive)
2205 e = gfc_get_expr ();
2206 e->symtree = symtree;
2207 e->expr_type = EXPR_VARIABLE;
2209 m = match_varspec (e, 0);
2213 /* Match a function reference. */
2215 m = gfc_match_actual_arglist (0, &actual_arglist);
2218 if (sym->attr.proc == PROC_ST_FUNCTION)
2219 gfc_error ("Statement function '%s' requires argument list at %C",
2222 gfc_error ("Function '%s' requires an argument list at %C",
2235 gfc_get_ha_sym_tree (name, &symtree); /* Can't fail */
2236 sym = symtree->n.sym;
2238 e = gfc_get_expr ();
2239 e->symtree = symtree;
2240 e->expr_type = EXPR_FUNCTION;
2241 e->value.function.actual = actual_arglist;
2242 e->where = gfc_current_locus;
2244 if (sym->as != NULL)
2245 e->rank = sym->as->rank;
2247 if (!sym->attr.function
2248 && gfc_add_function (&sym->attr, sym->name, NULL) == FAILURE)
2254 /* Check here for the existence of at least one argument for the
2255 iso_c_binding functions C_LOC, C_FUNLOC, and C_ASSOCIATED. The
2256 argument(s) given will be checked in gfc_iso_c_func_interface,
2257 during resolution of the function call. */
2258 if (sym->attr.is_iso_c == 1
2259 && (sym->from_intmod == INTMOD_ISO_C_BINDING
2260 && (sym->intmod_sym_id == ISOCBINDING_LOC
2261 || sym->intmod_sym_id == ISOCBINDING_FUNLOC
2262 || sym->intmod_sym_id == ISOCBINDING_ASSOCIATED)))
2264 /* make sure we were given a param */
2265 if (actual_arglist == NULL)
2267 gfc_error ("Missing argument to '%s' at %C", sym->name);
2273 if (sym->result == NULL)
2281 /* Special case for derived type variables that get their types
2282 via an IMPLICIT statement. This can't wait for the
2283 resolution phase. */
2285 if (gfc_peek_char () == '%'
2286 && sym->ts.type == BT_UNKNOWN
2287 && gfc_get_default_type (sym, sym->ns)->type == BT_DERIVED)
2288 gfc_set_default_type (sym, 0, sym->ns);
2290 /* If the symbol has a dimension attribute, the expression is a
2293 if (sym->attr.dimension)
2295 if (gfc_add_flavor (&sym->attr, FL_VARIABLE,
2296 sym->name, NULL) == FAILURE)
2302 e = gfc_get_expr ();
2303 e->symtree = symtree;
2304 e->expr_type = EXPR_VARIABLE;
2305 m = match_varspec (e, 0);
2309 /* Name is not an array, so we peek to see if a '(' implies a
2310 function call or a substring reference. Otherwise the
2311 variable is just a scalar. */
2313 gfc_gobble_whitespace ();
2314 if (gfc_peek_char () != '(')
2316 /* Assume a scalar variable */
2317 e = gfc_get_expr ();
2318 e->symtree = symtree;
2319 e->expr_type = EXPR_VARIABLE;
2321 if (gfc_add_flavor (&sym->attr, FL_VARIABLE,
2322 sym->name, NULL) == FAILURE)
2328 /*FIXME:??? match_varspec does set this for us: */
2330 m = match_varspec (e, 0);
2334 /* See if this is a function reference with a keyword argument
2335 as first argument. We do this because otherwise a spurious
2336 symbol would end up in the symbol table. */
2338 old_loc = gfc_current_locus;
2339 m2 = gfc_match (" ( %n =", argname);
2340 gfc_current_locus = old_loc;
2342 e = gfc_get_expr ();
2343 e->symtree = symtree;
2345 if (m2 != MATCH_YES)
2347 /* Try to figure out whether we're dealing with a character type.
2348 We're peeking ahead here, because we don't want to call
2349 match_substring if we're dealing with an implicitly typed
2350 non-character variable. */
2351 implicit_char = false;
2352 if (sym->ts.type == BT_UNKNOWN)
2354 ts = gfc_get_default_type (sym,NULL);
2355 if (ts->type == BT_CHARACTER)
2356 implicit_char = true;
2359 /* See if this could possibly be a substring reference of a name
2360 that we're not sure is a variable yet. */
2362 if ((implicit_char || sym->ts.type == BT_CHARACTER)
2363 && match_substring (sym->ts.cl, 0, &e->ref) == MATCH_YES)
2366 e->expr_type = EXPR_VARIABLE;
2368 if (sym->attr.flavor != FL_VARIABLE
2369 && gfc_add_flavor (&sym->attr, FL_VARIABLE,
2370 sym->name, NULL) == FAILURE)
2376 if (sym->ts.type == BT_UNKNOWN
2377 && gfc_set_default_type (sym, 1, NULL) == FAILURE)
2391 /* Give up, assume we have a function. */
2393 gfc_get_sym_tree (name, NULL, &symtree); /* Can't fail */
2394 sym = symtree->n.sym;
2395 e->expr_type = EXPR_FUNCTION;
2397 if (!sym->attr.function
2398 && gfc_add_function (&sym->attr, sym->name, NULL) == FAILURE)
2406 m = gfc_match_actual_arglist (0, &e->value.function.actual);
2408 gfc_error ("Missing argument list in function '%s' at %C", sym->name);
2416 /* If our new function returns a character, array or structure
2417 type, it might have subsequent references. */
2419 m = match_varspec (e, 0);
2426 gfc_get_sym_tree (name, NULL, &symtree); /* Can't fail */
2428 e = gfc_get_expr ();
2429 e->symtree = symtree;
2430 e->expr_type = EXPR_FUNCTION;
2432 m = gfc_match_actual_arglist (0, &e->value.function.actual);
2436 gfc_error ("Symbol at %C is not appropriate for an expression");
2452 /* Match a variable, ie something that can be assigned to. This
2453 starts as a symbol, can be a structure component or an array
2454 reference. It can be a function if the function doesn't have a
2455 separate RESULT variable. If the symbol has not been previously
2456 seen, we assume it is a variable.
2458 This function is called by two interface functions:
2459 gfc_match_variable, which has host_flag = 1, and
2460 gfc_match_equiv_variable, with host_flag = 0, to restrict the
2461 match of the symbol to the local scope. */
2464 match_variable (gfc_expr **result, int equiv_flag, int host_flag)
2472 /* Since nothing has any business being an lvalue in a module
2473 specification block, an interface block or a contains section,
2474 we force the changed_symbols mechanism to work by setting
2475 host_flag to 0. This prevents valid symbols that have the name
2476 of keywords, such as 'end', being turned into variables by
2477 failed matching to assignments for, eg., END INTERFACE. */
2478 if (gfc_current_state () == COMP_MODULE
2479 || gfc_current_state () == COMP_INTERFACE
2480 || gfc_current_state () == COMP_CONTAINS)
2483 m = gfc_match_sym_tree (&st, host_flag);
2486 where = gfc_current_locus;
2490 /* If this is an implicit do loop index and implicitly typed,
2491 it should not be host associated. */
2492 m = check_for_implicit_index (&st, &sym);
2496 sym->attr.implied_index = 0;
2498 gfc_set_sym_referenced (sym);
2499 switch (sym->attr.flavor)
2502 if (sym->attr.protected && sym->attr.use_assoc)
2504 gfc_error ("Assigning to PROTECTED variable at %C");
2510 if (sym->attr.access == ACCESS_PUBLIC
2511 || sym->attr.access == ACCESS_PRIVATE)
2513 if (gfc_add_flavor (&sym->attr, FL_VARIABLE,
2514 sym->name, NULL) == FAILURE)
2520 gfc_error ("Named constant at %C in an EQUIVALENCE");
2522 gfc_error ("Cannot assign to a named constant at %C");
2527 /* Check for a nonrecursive function result */
2528 if (sym->attr.function && (sym->result == sym || sym->attr.entry)
2529 && !sym->attr.external)
2531 /* If a function result is a derived type, then the derived
2532 type may still have to be resolved. */
2534 if (sym->ts.type == BT_DERIVED
2535 && gfc_use_derived (sym->ts.derived) == NULL)
2540 /* Fall through to error */
2543 gfc_error ("Expected VARIABLE at %C");
2547 /* Special case for derived type variables that get their types
2548 via an IMPLICIT statement. This can't wait for the
2549 resolution phase. */
2552 gfc_namespace * implicit_ns;
2554 if (gfc_current_ns->proc_name == sym)
2555 implicit_ns = gfc_current_ns;
2557 implicit_ns = sym->ns;
2559 if (gfc_peek_char () == '%'
2560 && sym->ts.type == BT_UNKNOWN
2561 && gfc_get_default_type (sym, implicit_ns)->type == BT_DERIVED)
2562 gfc_set_default_type (sym, 0, implicit_ns);
2565 expr = gfc_get_expr ();
2567 expr->expr_type = EXPR_VARIABLE;
2570 expr->where = where;
2572 /* Now see if we have to do more. */
2573 m = match_varspec (expr, equiv_flag);
2576 gfc_free_expr (expr);
2586 gfc_match_variable (gfc_expr **result, int equiv_flag)
2588 return match_variable (result, equiv_flag, 1);
2593 gfc_match_equiv_variable (gfc_expr **result)
2595 return match_variable (result, 1, 0);