1 /* Routines for manipulation of expression nodes.
2 Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2006 Free Software
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 2, 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 COPYING. If not, write to the Free
20 Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
29 /* Get a new expr node. */
36 e = gfc_getmem (sizeof (gfc_expr));
38 gfc_clear_ts (&e->ts);
47 /* Free an argument list and everything below it. */
50 gfc_free_actual_arglist (gfc_actual_arglist * a1)
52 gfc_actual_arglist *a2;
57 gfc_free_expr (a1->expr);
64 /* Copy an arglist structure and all of the arguments. */
67 gfc_copy_actual_arglist (gfc_actual_arglist * p)
69 gfc_actual_arglist *head, *tail, *new;
73 for (; p; p = p->next)
75 new = gfc_get_actual_arglist ();
78 new->expr = gfc_copy_expr (p->expr);
93 /* Free a list of reference structures. */
96 gfc_free_ref_list (gfc_ref * p)
108 for (i = 0; i < GFC_MAX_DIMENSIONS; i++)
110 gfc_free_expr (p->u.ar.start[i]);
111 gfc_free_expr (p->u.ar.end[i]);
112 gfc_free_expr (p->u.ar.stride[i]);
118 gfc_free_expr (p->u.ss.start);
119 gfc_free_expr (p->u.ss.end);
131 /* Workhorse function for gfc_free_expr() that frees everything
132 beneath an expression node, but not the node itself. This is
133 useful when we want to simplify a node and replace it with
134 something else or the expression node belongs to another structure. */
137 free_expr0 (gfc_expr * e)
141 switch (e->expr_type)
146 gfc_free (e->value.character.string);
153 mpz_clear (e->value.integer);
157 mpfr_clear (e->value.real);
162 gfc_free (e->value.character.string);
166 mpfr_clear (e->value.complex.r);
167 mpfr_clear (e->value.complex.i);
177 if (e->value.op.op1 != NULL)
178 gfc_free_expr (e->value.op.op1);
179 if (e->value.op.op2 != NULL)
180 gfc_free_expr (e->value.op.op2);
184 gfc_free_actual_arglist (e->value.function.actual);
192 gfc_free_constructor (e->value.constructor);
196 gfc_free (e->value.character.string);
203 gfc_internal_error ("free_expr0(): Bad expr type");
206 /* Free a shape array. */
207 if (e->shape != NULL)
209 for (n = 0; n < e->rank; n++)
210 mpz_clear (e->shape[n]);
215 gfc_free_ref_list (e->ref);
217 memset (e, '\0', sizeof (gfc_expr));
221 /* Free an expression node and everything beneath it. */
224 gfc_free_expr (gfc_expr * e)
235 /* Graft the *src expression onto the *dest subexpression. */
238 gfc_replace_expr (gfc_expr * dest, gfc_expr * src)
248 /* Try to extract an integer constant from the passed expression node.
249 Returns an error message or NULL if the result is set. It is
250 tempting to generate an error and return SUCCESS or FAILURE, but
251 failure is OK for some callers. */
254 gfc_extract_int (gfc_expr * expr, int *result)
257 if (expr->expr_type != EXPR_CONSTANT)
258 return _("Constant expression required at %C");
260 if (expr->ts.type != BT_INTEGER)
261 return _("Integer expression required at %C");
263 if ((mpz_cmp_si (expr->value.integer, INT_MAX) > 0)
264 || (mpz_cmp_si (expr->value.integer, INT_MIN) < 0))
266 return _("Integer value too large in expression at %C");
269 *result = (int) mpz_get_si (expr->value.integer);
275 /* Recursively copy a list of reference structures. */
278 copy_ref (gfc_ref * src)
286 dest = gfc_get_ref ();
287 dest->type = src->type;
292 ar = gfc_copy_array_ref (&src->u.ar);
298 dest->u.c = src->u.c;
302 dest->u.ss = src->u.ss;
303 dest->u.ss.start = gfc_copy_expr (src->u.ss.start);
304 dest->u.ss.end = gfc_copy_expr (src->u.ss.end);
308 dest->next = copy_ref (src->next);
314 /* Detect whether an expression has any vector index array
318 gfc_has_vector_index (gfc_expr *e)
322 for (ref = e->ref; ref; ref = ref->next)
323 if (ref->type == REF_ARRAY)
324 for (i = 0; i < ref->u.ar.dimen; i++)
325 if (ref->u.ar.dimen_type[i] == DIMEN_VECTOR)
331 /* Copy a shape array. */
334 gfc_copy_shape (mpz_t * shape, int rank)
342 new_shape = gfc_get_shape (rank);
344 for (n = 0; n < rank; n++)
345 mpz_init_set (new_shape[n], shape[n]);
351 /* Copy a shape array excluding dimension N, where N is an integer
352 constant expression. Dimensions are numbered in fortran style --
355 So, if the original shape array contains R elements
356 { s1 ... sN-1 sN sN+1 ... sR-1 sR}
357 the result contains R-1 elements:
358 { s1 ... sN-1 sN+1 ... sR-1}
360 If anything goes wrong -- N is not a constant, its value is out
361 of range -- or anything else, just returns NULL.
365 gfc_copy_shape_excluding (mpz_t * shape, int rank, gfc_expr * dim)
367 mpz_t *new_shape, *s;
373 || dim->expr_type != EXPR_CONSTANT
374 || dim->ts.type != BT_INTEGER)
377 n = mpz_get_si (dim->value.integer);
378 n--; /* Convert to zero based index */
379 if (n < 0 || n >= rank)
382 s = new_shape = gfc_get_shape (rank-1);
384 for (i = 0; i < rank; i++)
388 mpz_init_set (*s, shape[i]);
395 /* Given an expression pointer, return a copy of the expression. This
396 subroutine is recursive. */
399 gfc_copy_expr (gfc_expr * p)
410 switch (q->expr_type)
413 s = gfc_getmem (p->value.character.length + 1);
414 q->value.character.string = s;
416 memcpy (s, p->value.character.string, p->value.character.length + 1);
422 s = gfc_getmem (p->value.character.length + 1);
423 q->value.character.string = s;
425 memcpy (s, p->value.character.string,
426 p->value.character.length + 1);
432 mpz_init_set (q->value.integer, p->value.integer);
436 gfc_set_model_kind (q->ts.kind);
437 mpfr_init (q->value.real);
438 mpfr_set (q->value.real, p->value.real, GFC_RND_MODE);
442 gfc_set_model_kind (q->ts.kind);
443 mpfr_init (q->value.complex.r);
444 mpfr_init (q->value.complex.i);
445 mpfr_set (q->value.complex.r, p->value.complex.r, GFC_RND_MODE);
446 mpfr_set (q->value.complex.i, p->value.complex.i, GFC_RND_MODE);
451 s = gfc_getmem (p->value.character.length + 1);
452 q->value.character.string = s;
454 memcpy (s, p->value.character.string,
455 p->value.character.length + 1);
460 break; /* Already done */
464 gfc_internal_error ("gfc_copy_expr(): Bad expr node");
471 switch (q->value.op.operator)
474 case INTRINSIC_UPLUS:
475 case INTRINSIC_UMINUS:
476 q->value.op.op1 = gfc_copy_expr (p->value.op.op1);
479 default: /* Binary operators */
480 q->value.op.op1 = gfc_copy_expr (p->value.op.op1);
481 q->value.op.op2 = gfc_copy_expr (p->value.op.op2);
488 q->value.function.actual =
489 gfc_copy_actual_arglist (p->value.function.actual);
494 q->value.constructor = gfc_copy_constructor (p->value.constructor);
502 q->shape = gfc_copy_shape (p->shape, p->rank);
504 q->ref = copy_ref (p->ref);
510 /* Return the maximum kind of two expressions. In general, higher
511 kind numbers mean more precision for numeric types. */
514 gfc_kind_max (gfc_expr * e1, gfc_expr * e2)
517 return (e1->ts.kind > e2->ts.kind) ? e1->ts.kind : e2->ts.kind;
521 /* Returns nonzero if the type is numeric, zero otherwise. */
524 numeric_type (bt type)
527 return type == BT_COMPLEX || type == BT_REAL || type == BT_INTEGER;
531 /* Returns nonzero if the typespec is a numeric type, zero otherwise. */
534 gfc_numeric_ts (gfc_typespec * ts)
537 return numeric_type (ts->type);
541 /* Returns an expression node that is an integer constant. */
550 p->expr_type = EXPR_CONSTANT;
551 p->ts.type = BT_INTEGER;
552 p->ts.kind = gfc_default_integer_kind;
554 p->where = gfc_current_locus;
555 mpz_init_set_si (p->value.integer, i);
561 /* Returns an expression node that is a logical constant. */
564 gfc_logical_expr (int i, locus * where)
570 p->expr_type = EXPR_CONSTANT;
571 p->ts.type = BT_LOGICAL;
572 p->ts.kind = gfc_default_logical_kind;
575 where = &gfc_current_locus;
577 p->value.logical = i;
583 /* Return an expression node with an optional argument list attached.
584 A variable number of gfc_expr pointers are strung together in an
585 argument list with a NULL pointer terminating the list. */
588 gfc_build_conversion (gfc_expr * e)
593 p->expr_type = EXPR_FUNCTION;
595 p->value.function.actual = NULL;
597 p->value.function.actual = gfc_get_actual_arglist ();
598 p->value.function.actual->expr = e;
604 /* Given an expression node with some sort of numeric binary
605 expression, insert type conversions required to make the operands
608 The exception is that the operands of an exponential don't have to
609 have the same type. If possible, the base is promoted to the type
610 of the exponent. For example, 1**2.3 becomes 1.0**2.3, but
611 1.0**2 stays as it is. */
614 gfc_type_convert_binary (gfc_expr * e)
618 op1 = e->value.op.op1;
619 op2 = e->value.op.op2;
621 if (op1->ts.type == BT_UNKNOWN || op2->ts.type == BT_UNKNOWN)
623 gfc_clear_ts (&e->ts);
627 /* Kind conversions of same type. */
628 if (op1->ts.type == op2->ts.type)
631 if (op1->ts.kind == op2->ts.kind)
633 /* No type conversions. */
638 if (op1->ts.kind > op2->ts.kind)
639 gfc_convert_type (op2, &op1->ts, 2);
641 gfc_convert_type (op1, &op2->ts, 2);
647 /* Integer combined with real or complex. */
648 if (op2->ts.type == BT_INTEGER)
652 /* Special case for ** operator. */
653 if (e->value.op.operator == INTRINSIC_POWER)
656 gfc_convert_type (e->value.op.op2, &e->ts, 2);
660 if (op1->ts.type == BT_INTEGER)
663 gfc_convert_type (e->value.op.op1, &e->ts, 2);
667 /* Real combined with complex. */
668 e->ts.type = BT_COMPLEX;
669 if (op1->ts.kind > op2->ts.kind)
670 e->ts.kind = op1->ts.kind;
672 e->ts.kind = op2->ts.kind;
673 if (op1->ts.type != BT_COMPLEX || op1->ts.kind != e->ts.kind)
674 gfc_convert_type (e->value.op.op1, &e->ts, 2);
675 if (op2->ts.type != BT_COMPLEX || op2->ts.kind != e->ts.kind)
676 gfc_convert_type (e->value.op.op2, &e->ts, 2);
683 /* Function to determine if an expression is constant or not. This
684 function expects that the expression has already been simplified. */
687 gfc_is_constant_expr (gfc_expr * e)
690 gfc_actual_arglist *arg;
696 switch (e->expr_type)
699 rv = (gfc_is_constant_expr (e->value.op.op1)
700 && (e->value.op.op2 == NULL
701 || gfc_is_constant_expr (e->value.op.op2)));
710 /* Call to intrinsic with at least one argument. */
712 if (e->value.function.isym && e->value.function.actual)
714 for (arg = e->value.function.actual; arg; arg = arg->next)
716 if (!gfc_is_constant_expr (arg->expr))
730 rv = (gfc_is_constant_expr (e->ref->u.ss.start)
731 && gfc_is_constant_expr (e->ref->u.ss.end));
736 for (c = e->value.constructor; c; c = c->next)
737 if (!gfc_is_constant_expr (c->expr))
745 rv = gfc_constant_ac (e);
749 gfc_internal_error ("gfc_is_constant_expr(): Unknown expression type");
756 /* Try to collapse intrinsic expressions. */
759 simplify_intrinsic_op (gfc_expr * p, int type)
761 gfc_expr *op1, *op2, *result;
763 if (p->value.op.operator == INTRINSIC_USER)
766 op1 = p->value.op.op1;
767 op2 = p->value.op.op2;
769 if (gfc_simplify_expr (op1, type) == FAILURE)
771 if (gfc_simplify_expr (op2, type) == FAILURE)
774 if (!gfc_is_constant_expr (op1)
775 || (op2 != NULL && !gfc_is_constant_expr (op2)))
779 p->value.op.op1 = NULL;
780 p->value.op.op2 = NULL;
782 switch (p->value.op.operator)
784 case INTRINSIC_UPLUS:
785 case INTRINSIC_PARENTHESES:
786 result = gfc_uplus (op1);
789 case INTRINSIC_UMINUS:
790 result = gfc_uminus (op1);
794 result = gfc_add (op1, op2);
797 case INTRINSIC_MINUS:
798 result = gfc_subtract (op1, op2);
801 case INTRINSIC_TIMES:
802 result = gfc_multiply (op1, op2);
805 case INTRINSIC_DIVIDE:
806 result = gfc_divide (op1, op2);
809 case INTRINSIC_POWER:
810 result = gfc_power (op1, op2);
813 case INTRINSIC_CONCAT:
814 result = gfc_concat (op1, op2);
818 result = gfc_eq (op1, op2);
822 result = gfc_ne (op1, op2);
826 result = gfc_gt (op1, op2);
830 result = gfc_ge (op1, op2);
834 result = gfc_lt (op1, op2);
838 result = gfc_le (op1, op2);
842 result = gfc_not (op1);
846 result = gfc_and (op1, op2);
850 result = gfc_or (op1, op2);
854 result = gfc_eqv (op1, op2);
858 result = gfc_neqv (op1, op2);
862 gfc_internal_error ("simplify_intrinsic_op(): Bad operator");
872 result->rank = p->rank;
873 result->where = p->where;
874 gfc_replace_expr (p, result);
880 /* Subroutine to simplify constructor expressions. Mutually recursive
881 with gfc_simplify_expr(). */
884 simplify_constructor (gfc_constructor * c, int type)
887 for (; c; c = c->next)
890 && (gfc_simplify_expr (c->iterator->start, type) == FAILURE
891 || gfc_simplify_expr (c->iterator->end, type) == FAILURE
892 || gfc_simplify_expr (c->iterator->step, type) == FAILURE))
895 if (c->expr && gfc_simplify_expr (c->expr, type) == FAILURE)
903 /* Pull a single array element out of an array constructor. */
906 find_array_element (gfc_constructor * cons, gfc_array_ref * ar,
907 gfc_constructor ** rval)
909 unsigned long nelemen;
919 mpz_init_set_ui (offset, 0);
921 for (i = 0; i < ar->dimen; i++)
923 e = gfc_copy_expr (ar->start[i]);
924 if (e->expr_type != EXPR_CONSTANT)
930 /* Check the bounds. */
932 && (mpz_cmp (e->value.integer,
933 ar->as->upper[i]->value.integer) > 0
934 || mpz_cmp (e->value.integer,
935 ar->as->lower[i]->value.integer) < 0))
937 gfc_error ("index in dimension %d is out of bounds "
938 "at %L", i + 1, &ar->c_where[i]);
944 mpz_sub (delta, e->value.integer,
945 ar->as->lower[i]->value.integer);
946 mpz_add (offset, offset, delta);
951 for (nelemen = mpz_get_ui (offset); nelemen > 0; nelemen--)
972 /* Find a component of a structure constructor. */
974 static gfc_constructor *
975 find_component_ref (gfc_constructor * cons, gfc_ref * ref)
980 comp = ref->u.c.sym->components;
981 pick = ref->u.c.component;
992 /* Replace an expression with the contents of a constructor, removing
993 the subobject reference in the process. */
996 remove_subobject_ref (gfc_expr * p, gfc_constructor * cons)
1002 e->ref = p->ref->next;
1003 p->ref->next = NULL;
1004 gfc_replace_expr (p, e);
1008 /* Pull an array section out of an array constructor. */
1011 find_array_section (gfc_expr *expr, gfc_ref *ref)
1016 long unsigned one = 1;
1017 mpz_t start[GFC_MAX_DIMENSIONS];
1018 mpz_t end[GFC_MAX_DIMENSIONS];
1019 mpz_t stride[GFC_MAX_DIMENSIONS];
1020 mpz_t delta[GFC_MAX_DIMENSIONS];
1021 mpz_t ctr[GFC_MAX_DIMENSIONS];
1028 gfc_constructor *cons;
1029 gfc_constructor *base;
1039 base = expr->value.constructor;
1040 expr->value.constructor = NULL;
1042 rank = ref->u.ar.as->rank;
1044 if (expr->shape == NULL)
1045 expr->shape = gfc_get_shape (rank);
1047 mpz_init_set_ui (delta_mpz, one);
1048 mpz_init_set_ui (nelts, one);
1051 /* Do the initialization now, so that we can cleanup without
1052 keeping track of where we were. */
1053 for (d = 0; d < rank; d++)
1055 mpz_init (delta[d]);
1056 mpz_init (start[d]);
1059 mpz_init (stride[d]);
1062 /* Build the counters to clock through the array reference. */
1063 for (d = 0; d < rank; d++)
1065 /* Make this stretch of code easier on the eye! */
1066 begin = ref->u.ar.start[d];
1067 finish = ref->u.ar.end[d];
1068 step = ref->u.ar.stride[d];
1069 lower = ref->u.ar.as->lower[d];
1070 upper = ref->u.ar.as->upper[d];
1072 if ((begin && begin->expr_type != EXPR_CONSTANT)
1073 || (finish && finish->expr_type != EXPR_CONSTANT)
1074 || (step && step->expr_type != EXPR_CONSTANT))
1080 /* Obtain the stride. */
1082 mpz_set (stride[d], step->value.integer);
1084 mpz_set_ui (stride[d], one);
1086 if (mpz_cmp_ui (stride[d], 0) == 0)
1087 mpz_set_ui (stride[d], one);
1089 /* Obtain the start value for the index. */
1091 mpz_set (start[d], begin->value.integer);
1093 mpz_set (start[d], lower->value.integer);
1095 mpz_set (ctr[d], start[d]);
1097 /* Obtain the end value for the index. */
1099 mpz_set (end[d], finish->value.integer);
1101 mpz_set (end[d], upper->value.integer);
1103 /* Separate 'if' because elements sometimes arrive with
1105 if (ref->u.ar.dimen_type[d] == DIMEN_ELEMENT)
1106 mpz_set (end [d], begin->value.integer);
1108 /* Check the bounds. */
1109 if (mpz_cmp (ctr[d], upper->value.integer) > 0
1110 || mpz_cmp (end[d], upper->value.integer) > 0
1111 || mpz_cmp (ctr[d], lower->value.integer) < 0
1112 || mpz_cmp (end[d], lower->value.integer) < 0)
1114 gfc_error ("index in dimension %d is out of bounds "
1115 "at %L", d + 1, &ref->u.ar.c_where[d]);
1120 /* Calculate the number of elements and the shape. */
1121 mpz_abs (tmp_mpz, stride[d]);
1122 mpz_div (tmp_mpz, stride[d], tmp_mpz);
1123 mpz_add (tmp_mpz, end[d], tmp_mpz);
1124 mpz_sub (tmp_mpz, tmp_mpz, ctr[d]);
1125 mpz_div (tmp_mpz, tmp_mpz, stride[d]);
1126 mpz_mul (nelts, nelts, tmp_mpz);
1128 mpz_set (expr->shape[d], tmp_mpz);
1130 /* Calculate the 'stride' (=delta) for conversion of the
1131 counter values into the index along the constructor. */
1132 mpz_set (delta[d], delta_mpz);
1133 mpz_sub (tmp_mpz, upper->value.integer, lower->value.integer);
1134 mpz_add_ui (tmp_mpz, tmp_mpz, one);
1135 mpz_mul (delta_mpz, delta_mpz, tmp_mpz);
1143 /* Now clock through the array reference, calculating the index in
1144 the source constructor and transferring the elements to the new
1146 for (idx = 0; idx < (int)mpz_get_si (nelts); idx++)
1148 if (ref->u.ar.offset)
1149 mpz_set (ptr, ref->u.ar.offset->value.integer);
1151 mpz_init_set_ui (ptr, 0);
1153 mpz_set_ui (stop, one);
1154 for (d = 0; d < rank; d++)
1156 mpz_set (tmp_mpz, ctr[d]);
1157 mpz_sub_ui (tmp_mpz, tmp_mpz, one);
1158 mpz_mul (tmp_mpz, tmp_mpz, delta[d]);
1159 mpz_add (ptr, ptr, tmp_mpz);
1161 mpz_mul (tmp_mpz, stride[d], stop);
1162 mpz_add (ctr[d], ctr[d], tmp_mpz);
1164 mpz_set (tmp_mpz, end[d]);
1165 if (mpz_cmp_ui (stride[d], 0) > 0 ?
1166 mpz_cmp (ctr[d], tmp_mpz) > 0 :
1167 mpz_cmp (ctr[d], tmp_mpz) < 0)
1168 mpz_set (ctr[d], start[d]);
1170 mpz_set_ui (stop, 0);
1173 /* There must be a better way of dealing with negative strides
1174 than resetting the index and the constructor pointer! */
1175 if (mpz_cmp (ptr, index) < 0)
1177 mpz_set_ui (index, 0);
1181 while (mpz_cmp (ptr, index) > 0)
1183 mpz_add_ui (index, index, one);
1187 gfc_append_constructor (expr, gfc_copy_expr (cons->expr));
1196 mpz_clear (delta_mpz);
1197 mpz_clear (tmp_mpz);
1199 for (d = 0; d < rank; d++)
1201 mpz_clear (delta[d]);
1202 mpz_clear (start[d]);
1205 mpz_clear (stride[d]);
1207 gfc_free_constructor (base);
1211 /* Pull a substring out of an expression. */
1214 find_substring_ref (gfc_expr *p, gfc_expr **newp)
1220 if (p->ref->u.ss.start->expr_type != EXPR_CONSTANT
1221 || p->ref->u.ss.end->expr_type != EXPR_CONSTANT)
1224 *newp = gfc_copy_expr (p);
1225 chr = p->value.character.string;
1226 end = (int)mpz_get_ui (p->ref->u.ss.end->value.integer);
1227 start = (int)mpz_get_ui (p->ref->u.ss.start->value.integer);
1229 (*newp)->value.character.length = end - start + 1;
1230 strncpy ((*newp)->value.character.string, &chr[start - 1],
1231 (*newp)->value.character.length);
1237 /* Simplify a subobject reference of a constructor. This occurs when
1238 parameter variable values are substituted. */
1241 simplify_const_ref (gfc_expr * p)
1243 gfc_constructor *cons;
1248 switch (p->ref->type)
1251 switch (p->ref->u.ar.type)
1254 if (find_array_element (p->value.constructor,
1262 remove_subobject_ref (p, cons);
1266 if (find_array_section (p, p->ref) == FAILURE)
1268 p->ref->u.ar.type = AR_FULL;
1273 if (p->ref->next != NULL
1274 && (p->ts.type == BT_CHARACTER || p->ts.type == BT_DERIVED))
1276 cons = p->value.constructor;
1277 for (; cons; cons = cons->next)
1279 cons->expr->ref = copy_ref (p->ref->next);
1280 simplify_const_ref (cons->expr);
1283 gfc_free_ref_list (p->ref);
1294 cons = find_component_ref (p->value.constructor, p->ref);
1295 remove_subobject_ref (p, cons);
1299 if (find_substring_ref (p, &newp) == FAILURE)
1302 gfc_replace_expr (p, newp);
1303 gfc_free_ref_list (p->ref);
1313 /* Simplify a chain of references. */
1316 simplify_ref_chain (gfc_ref * ref, int type)
1320 for (; ref; ref = ref->next)
1325 for (n = 0; n < ref->u.ar.dimen; n++)
1327 if (gfc_simplify_expr (ref->u.ar.start[n], type)
1330 if (gfc_simplify_expr (ref->u.ar.end[n], type)
1333 if (gfc_simplify_expr (ref->u.ar.stride[n], type)
1341 if (gfc_simplify_expr (ref->u.ss.start, type) == FAILURE)
1343 if (gfc_simplify_expr (ref->u.ss.end, type) == FAILURE)
1355 /* Try to substitute the value of a parameter variable. */
1357 simplify_parameter_variable (gfc_expr * p, int type)
1362 e = gfc_copy_expr (p->symtree->n.sym->value);
1366 /* Do not copy subobject refs for constant. */
1367 if (e->expr_type != EXPR_CONSTANT && p->ref != NULL)
1368 e->ref = copy_ref (p->ref);
1369 t = gfc_simplify_expr (e, type);
1371 /* Only use the simplification if it eliminated all subobject
1373 if (t == SUCCESS && ! e->ref)
1374 gfc_replace_expr (p, e);
1381 /* Given an expression, simplify it by collapsing constant
1382 expressions. Most simplification takes place when the expression
1383 tree is being constructed. If an intrinsic function is simplified
1384 at some point, we get called again to collapse the result against
1387 We work by recursively simplifying expression nodes, simplifying
1388 intrinsic functions where possible, which can lead to further
1389 constant collapsing. If an operator has constant operand(s), we
1390 rip the expression apart, and rebuild it, hoping that it becomes
1393 The expression type is defined for:
1394 0 Basic expression parsing
1395 1 Simplifying array constructors -- will substitute
1397 Returns FAILURE on error, SUCCESS otherwise.
1398 NOTE: Will return SUCCESS even if the expression can not be simplified. */
1401 gfc_simplify_expr (gfc_expr * p, int type)
1403 gfc_actual_arglist *ap;
1408 switch (p->expr_type)
1415 for (ap = p->value.function.actual; ap; ap = ap->next)
1416 if (gfc_simplify_expr (ap->expr, type) == FAILURE)
1419 if (p->value.function.isym != NULL
1420 && gfc_intrinsic_func_interface (p, 1) == MATCH_ERROR)
1425 case EXPR_SUBSTRING:
1426 if (simplify_ref_chain (p->ref, type) == FAILURE)
1429 if (gfc_is_constant_expr (p))
1434 gfc_extract_int (p->ref->u.ss.start, &start);
1435 start--; /* Convert from one-based to zero-based. */
1436 gfc_extract_int (p->ref->u.ss.end, &end);
1437 s = gfc_getmem (end - start + 1);
1438 memcpy (s, p->value.character.string + start, end - start);
1439 s[end] = '\0'; /* TODO: C-style string for debugging. */
1440 gfc_free (p->value.character.string);
1441 p->value.character.string = s;
1442 p->value.character.length = end - start;
1443 p->ts.cl = gfc_get_charlen ();
1444 p->ts.cl->next = gfc_current_ns->cl_list;
1445 gfc_current_ns->cl_list = p->ts.cl;
1446 p->ts.cl->length = gfc_int_expr (p->value.character.length);
1447 gfc_free_ref_list (p->ref);
1449 p->expr_type = EXPR_CONSTANT;
1454 if (simplify_intrinsic_op (p, type) == FAILURE)
1459 /* Only substitute array parameter variables if we are in an
1460 initialization expression, or we want a subsection. */
1461 if (p->symtree->n.sym->attr.flavor == FL_PARAMETER
1462 && (gfc_init_expr || p->ref
1463 || p->symtree->n.sym->value->expr_type != EXPR_ARRAY))
1465 if (simplify_parameter_variable (p, type) == FAILURE)
1472 gfc_simplify_iterator_var (p);
1475 /* Simplify subcomponent references. */
1476 if (simplify_ref_chain (p->ref, type) == FAILURE)
1481 case EXPR_STRUCTURE:
1483 if (simplify_ref_chain (p->ref, type) == FAILURE)
1486 if (simplify_constructor (p->value.constructor, type) == FAILURE)
1489 if (p->expr_type == EXPR_ARRAY
1490 && p->ref && p->ref->type == REF_ARRAY
1491 && p->ref->u.ar.type == AR_FULL)
1492 gfc_expand_constructor (p);
1494 if (simplify_const_ref (p) == FAILURE)
1504 /* Returns the type of an expression with the exception that iterator
1505 variables are automatically integers no matter what else they may
1512 if (e->expr_type == EXPR_VARIABLE && gfc_check_iter_variable (e) == SUCCESS)
1519 /* Check an intrinsic arithmetic operation to see if it is consistent
1520 with some type of expression. */
1522 static try check_init_expr (gfc_expr *);
1525 check_intrinsic_op (gfc_expr * e, try (*check_function) (gfc_expr *))
1527 gfc_expr *op1 = e->value.op.op1;
1528 gfc_expr *op2 = e->value.op.op2;
1530 if ((*check_function) (op1) == FAILURE)
1533 switch (e->value.op.operator)
1535 case INTRINSIC_UPLUS:
1536 case INTRINSIC_UMINUS:
1537 if (!numeric_type (et0 (op1)))
1547 if ((*check_function) (op2) == FAILURE)
1550 if (!(et0 (op1) == BT_CHARACTER && et0 (op2) == BT_CHARACTER)
1551 && !(numeric_type (et0 (op1)) && numeric_type (et0 (op2))))
1553 gfc_error ("Numeric or CHARACTER operands are required in "
1554 "expression at %L", &e->where);
1559 case INTRINSIC_PLUS:
1560 case INTRINSIC_MINUS:
1561 case INTRINSIC_TIMES:
1562 case INTRINSIC_DIVIDE:
1563 case INTRINSIC_POWER:
1564 if ((*check_function) (op2) == FAILURE)
1567 if (!numeric_type (et0 (op1)) || !numeric_type (et0 (op2)))
1570 if (e->value.op.operator == INTRINSIC_POWER
1571 && check_function == check_init_expr && et0 (op2) != BT_INTEGER)
1573 gfc_error ("Exponent at %L must be INTEGER for an initialization "
1574 "expression", &op2->where);
1580 case INTRINSIC_CONCAT:
1581 if ((*check_function) (op2) == FAILURE)
1584 if (et0 (op1) != BT_CHARACTER || et0 (op2) != BT_CHARACTER)
1586 gfc_error ("Concatenation operator in expression at %L "
1587 "must have two CHARACTER operands", &op1->where);
1591 if (op1->ts.kind != op2->ts.kind)
1593 gfc_error ("Concat operator at %L must concatenate strings of the "
1594 "same kind", &e->where);
1601 if (et0 (op1) != BT_LOGICAL)
1603 gfc_error (".NOT. operator in expression at %L must have a LOGICAL "
1604 "operand", &op1->where);
1613 case INTRINSIC_NEQV:
1614 if ((*check_function) (op2) == FAILURE)
1617 if (et0 (op1) != BT_LOGICAL || et0 (op2) != BT_LOGICAL)
1619 gfc_error ("LOGICAL operands are required in expression at %L",
1626 case INTRINSIC_PARENTHESES:
1630 gfc_error ("Only intrinsic operators can be used in expression at %L",
1638 gfc_error ("Numeric operands are required in expression at %L", &e->where);
1645 /* Certain inquiry functions are specifically allowed to have variable
1646 arguments, which is an exception to the normal requirement that an
1647 initialization function have initialization arguments. We head off
1648 this problem here. */
1651 check_inquiry (gfc_expr * e, int not_restricted)
1655 /* FIXME: This should be moved into the intrinsic definitions,
1656 to eliminate this ugly hack. */
1657 static const char * const inquiry_function[] = {
1658 "digits", "epsilon", "huge", "kind", "len", "maxexponent", "minexponent",
1659 "precision", "radix", "range", "tiny", "bit_size", "size", "shape",
1660 "lbound", "ubound", NULL
1665 /* An undeclared parameter will get us here (PR25018). */
1666 if (e->symtree == NULL)
1669 name = e->symtree->n.sym->name;
1671 for (i = 0; inquiry_function[i]; i++)
1672 if (strcmp (inquiry_function[i], name) == 0)
1675 if (inquiry_function[i] == NULL)
1678 e = e->value.function.actual->expr;
1680 if (e == NULL || e->expr_type != EXPR_VARIABLE)
1683 /* At this point we have an inquiry function with a variable argument. The
1684 type of the variable might be undefined, but we need it now, because the
1685 arguments of these functions are allowed to be undefined. */
1687 if (e->ts.type == BT_UNKNOWN)
1689 if (e->symtree->n.sym->ts.type == BT_UNKNOWN
1690 && gfc_set_default_type (e->symtree->n.sym, 0, gfc_current_ns)
1694 e->ts = e->symtree->n.sym->ts;
1697 /* Assumed character length will not reduce to a constant expression
1698 with LEN, as required by the standard. */
1699 if (i == 4 && not_restricted
1700 && e->symtree->n.sym->ts.type == BT_CHARACTER
1701 && e->symtree->n.sym->ts.cl->length == NULL)
1702 gfc_notify_std (GFC_STD_GNU, "assumed character length "
1703 "variable '%s' in constant expression at %L",
1704 e->symtree->n.sym->name, &e->where);
1710 /* Verify that an expression is an initialization expression. A side
1711 effect is that the expression tree is reduced to a single constant
1712 node if all goes well. This would normally happen when the
1713 expression is constructed but function references are assumed to be
1714 intrinsics in the context of initialization expressions. If
1715 FAILURE is returned an error message has been generated. */
1718 check_init_expr (gfc_expr * e)
1720 gfc_actual_arglist *ap;
1727 switch (e->expr_type)
1730 t = check_intrinsic_op (e, check_init_expr);
1732 t = gfc_simplify_expr (e, 0);
1739 if (check_inquiry (e, 1) != SUCCESS)
1742 for (ap = e->value.function.actual; ap; ap = ap->next)
1743 if (check_init_expr (ap->expr) == FAILURE)
1752 m = gfc_intrinsic_func_interface (e, 0);
1755 gfc_error ("Function '%s' in initialization expression at %L "
1756 "must be an intrinsic function",
1757 e->symtree->n.sym->name, &e->where);
1768 if (gfc_check_iter_variable (e) == SUCCESS)
1771 if (e->symtree->n.sym->attr.flavor == FL_PARAMETER)
1773 t = simplify_parameter_variable (e, 0);
1777 gfc_error ("Parameter '%s' at %L has not been declared or is "
1778 "a variable, which does not reduce to a constant "
1779 "expression", e->symtree->n.sym->name, &e->where);
1788 case EXPR_SUBSTRING:
1789 t = check_init_expr (e->ref->u.ss.start);
1793 t = check_init_expr (e->ref->u.ss.end);
1795 t = gfc_simplify_expr (e, 0);
1799 case EXPR_STRUCTURE:
1800 t = gfc_check_constructor (e, check_init_expr);
1804 t = gfc_check_constructor (e, check_init_expr);
1808 t = gfc_expand_constructor (e);
1812 t = gfc_check_constructor_type (e);
1816 gfc_internal_error ("check_init_expr(): Unknown expression type");
1823 /* Match an initialization expression. We work by first matching an
1824 expression, then reducing it to a constant. */
1827 gfc_match_init_expr (gfc_expr ** result)
1833 m = gfc_match_expr (&expr);
1838 t = gfc_resolve_expr (expr);
1840 t = check_init_expr (expr);
1845 gfc_free_expr (expr);
1849 if (expr->expr_type == EXPR_ARRAY
1850 && (gfc_check_constructor_type (expr) == FAILURE
1851 || gfc_expand_constructor (expr) == FAILURE))
1853 gfc_free_expr (expr);
1857 /* Not all inquiry functions are simplified to constant expressions
1858 so it is necessary to call check_inquiry again. */
1859 if (!gfc_is_constant_expr (expr)
1860 && check_inquiry (expr, 1) == FAILURE)
1862 gfc_error ("Initialization expression didn't reduce %C");
1873 static try check_restricted (gfc_expr *);
1875 /* Given an actual argument list, test to see that each argument is a
1876 restricted expression and optionally if the expression type is
1877 integer or character. */
1880 restricted_args (gfc_actual_arglist * a)
1882 for (; a; a = a->next)
1884 if (check_restricted (a->expr) == FAILURE)
1892 /************* Restricted/specification expressions *************/
1895 /* Make sure a non-intrinsic function is a specification function. */
1898 external_spec_function (gfc_expr * e)
1902 f = e->value.function.esym;
1904 if (f->attr.proc == PROC_ST_FUNCTION)
1906 gfc_error ("Specification function '%s' at %L cannot be a statement "
1907 "function", f->name, &e->where);
1911 if (f->attr.proc == PROC_INTERNAL)
1913 gfc_error ("Specification function '%s' at %L cannot be an internal "
1914 "function", f->name, &e->where);
1918 if (!f->attr.pure && !f->attr.elemental)
1920 gfc_error ("Specification function '%s' at %L must be PURE", f->name,
1925 if (f->attr.recursive)
1927 gfc_error ("Specification function '%s' at %L cannot be RECURSIVE",
1928 f->name, &e->where);
1932 return restricted_args (e->value.function.actual);
1936 /* Check to see that a function reference to an intrinsic is a
1937 restricted expression. */
1940 restricted_intrinsic (gfc_expr * e)
1942 /* TODO: Check constraints on inquiry functions. 7.1.6.2 (7). */
1943 if (check_inquiry (e, 0) == SUCCESS)
1946 return restricted_args (e->value.function.actual);
1950 /* Verify that an expression is a restricted expression. Like its
1951 cousin check_init_expr(), an error message is generated if we
1955 check_restricted (gfc_expr * e)
1963 switch (e->expr_type)
1966 t = check_intrinsic_op (e, check_restricted);
1968 t = gfc_simplify_expr (e, 0);
1973 t = e->value.function.esym ?
1974 external_spec_function (e) : restricted_intrinsic (e);
1979 sym = e->symtree->n.sym;
1982 if (sym->attr.optional)
1984 gfc_error ("Dummy argument '%s' at %L cannot be OPTIONAL",
1985 sym->name, &e->where);
1989 if (sym->attr.intent == INTENT_OUT)
1991 gfc_error ("Dummy argument '%s' at %L cannot be INTENT(OUT)",
1992 sym->name, &e->where);
1996 /* gfc_is_formal_arg broadcasts that a formal argument list is being processed
1997 in resolve.c(resolve_formal_arglist). This is done so that host associated
1998 dummy array indices are accepted (PR23446). */
1999 if (sym->attr.in_common
2000 || sym->attr.use_assoc
2002 || sym->ns != gfc_current_ns
2003 || (sym->ns->proc_name != NULL
2004 && sym->ns->proc_name->attr.flavor == FL_MODULE)
2005 || gfc_is_formal_arg ())
2011 gfc_error ("Variable '%s' cannot appear in the expression at %L",
2012 sym->name, &e->where);
2021 case EXPR_SUBSTRING:
2022 t = gfc_specification_expr (e->ref->u.ss.start);
2026 t = gfc_specification_expr (e->ref->u.ss.end);
2028 t = gfc_simplify_expr (e, 0);
2032 case EXPR_STRUCTURE:
2033 t = gfc_check_constructor (e, check_restricted);
2037 t = gfc_check_constructor (e, check_restricted);
2041 gfc_internal_error ("check_restricted(): Unknown expression type");
2048 /* Check to see that an expression is a specification expression. If
2049 we return FAILURE, an error has been generated. */
2052 gfc_specification_expr (gfc_expr * e)
2057 if (e->ts.type != BT_INTEGER)
2059 gfc_error ("Expression at %L must be of INTEGER type", &e->where);
2065 gfc_error ("Expression at %L must be scalar", &e->where);
2069 if (gfc_simplify_expr (e, 0) == FAILURE)
2072 return check_restricted (e);
2076 /************** Expression conformance checks. *************/
2078 /* Given two expressions, make sure that the arrays are conformable. */
2081 gfc_check_conformance (const char *optype_msgid,
2082 gfc_expr * op1, gfc_expr * op2)
2084 int op1_flag, op2_flag, d;
2085 mpz_t op1_size, op2_size;
2088 if (op1->rank == 0 || op2->rank == 0)
2091 if (op1->rank != op2->rank)
2093 gfc_error ("Incompatible ranks in %s at %L", _(optype_msgid),
2100 for (d = 0; d < op1->rank; d++)
2102 op1_flag = gfc_array_dimen_size (op1, d, &op1_size) == SUCCESS;
2103 op2_flag = gfc_array_dimen_size (op2, d, &op2_size) == SUCCESS;
2105 if (op1_flag && op2_flag && mpz_cmp (op1_size, op2_size) != 0)
2107 gfc_error ("different shape for %s at %L on dimension %d (%d/%d)",
2108 _(optype_msgid), &op1->where, d + 1,
2109 (int) mpz_get_si (op1_size),
2110 (int) mpz_get_si (op2_size));
2116 mpz_clear (op1_size);
2118 mpz_clear (op2_size);
2128 /* Given an assignable expression and an arbitrary expression, make
2129 sure that the assignment can take place. */
2132 gfc_check_assign (gfc_expr * lvalue, gfc_expr * rvalue, int conform)
2136 sym = lvalue->symtree->n.sym;
2138 if (sym->attr.intent == INTENT_IN)
2140 gfc_error ("Can't assign to INTENT(IN) variable '%s' at %L",
2141 sym->name, &lvalue->where);
2145 /* 12.5.2.2, Note 12.26: The result variable is very similar to any other
2146 variable local to a function subprogram. Its existence begins when
2147 execution of the function is initiated and ends when execution of the
2148 function is terminated.....
2149 Therefore, the left hand side is no longer a varaiable, when it is:*/
2150 if (sym->attr.flavor == FL_PROCEDURE
2151 && sym->attr.proc != PROC_ST_FUNCTION
2152 && !sym->attr.external)
2157 /* (i) Use associated; */
2158 if (sym->attr.use_assoc)
2161 /* (ii) The assignment is in the main program; or */
2162 if (gfc_current_ns->proc_name->attr.is_main_program)
2165 /* (iii) A module or internal procedure.... */
2166 if ((gfc_current_ns->proc_name->attr.proc == PROC_INTERNAL
2167 || gfc_current_ns->proc_name->attr.proc == PROC_MODULE)
2168 && gfc_current_ns->parent
2169 && (!(gfc_current_ns->parent->proc_name->attr.function
2170 || gfc_current_ns->parent->proc_name->attr.subroutine)
2171 || gfc_current_ns->parent->proc_name->attr.is_main_program))
2173 /* .... that is not a function.... */
2174 if (!gfc_current_ns->proc_name->attr.function)
2177 /* .... or is not an entry and has a different name. */
2178 if (!sym->attr.entry && sym->name != gfc_current_ns->proc_name->name)
2184 gfc_error ("'%s' at %L is not a VALUE", sym->name, &lvalue->where);
2189 if (rvalue->rank != 0 && lvalue->rank != rvalue->rank)
2191 gfc_error ("Incompatible ranks %d and %d in assignment at %L",
2192 lvalue->rank, rvalue->rank, &lvalue->where);
2196 if (lvalue->ts.type == BT_UNKNOWN)
2198 gfc_error ("Variable type is UNKNOWN in assignment at %L",
2203 if (rvalue->expr_type == EXPR_NULL)
2205 gfc_error ("NULL appears on right-hand side in assignment at %L",
2210 if (sym->attr.cray_pointee
2211 && lvalue->ref != NULL
2212 && lvalue->ref->u.ar.type == AR_FULL
2213 && lvalue->ref->u.ar.as->cp_was_assumed)
2215 gfc_error ("Vector assignment to assumed-size Cray Pointee at %L"
2216 " is illegal.", &lvalue->where);
2220 /* This is possibly a typo: x = f() instead of x => f() */
2221 if (gfc_option.warn_surprising
2222 && rvalue->expr_type == EXPR_FUNCTION
2223 && rvalue->symtree->n.sym->attr.pointer)
2224 gfc_warning ("POINTER valued function appears on right-hand side of "
2225 "assignment at %L", &rvalue->where);
2227 /* Check size of array assignments. */
2228 if (lvalue->rank != 0 && rvalue->rank != 0
2229 && gfc_check_conformance ("Array assignment", lvalue, rvalue) != SUCCESS)
2232 if (gfc_compare_types (&lvalue->ts, &rvalue->ts))
2237 /* Numeric can be converted to any other numeric. And Hollerith can be
2238 converted to any other type. */
2239 if ((gfc_numeric_ts (&lvalue->ts) && gfc_numeric_ts (&rvalue->ts))
2240 || rvalue->ts.type == BT_HOLLERITH)
2243 if (lvalue->ts.type == BT_LOGICAL && rvalue->ts.type == BT_LOGICAL)
2246 gfc_error ("Incompatible types in assignment at %L, %s to %s",
2247 &rvalue->where, gfc_typename (&rvalue->ts),
2248 gfc_typename (&lvalue->ts));
2253 return gfc_convert_type (rvalue, &lvalue->ts, 1);
2257 /* Check that a pointer assignment is OK. We first check lvalue, and
2258 we only check rvalue if it's not an assignment to NULL() or a
2259 NULLIFY statement. */
2262 gfc_check_pointer_assign (gfc_expr * lvalue, gfc_expr * rvalue)
2264 symbol_attribute attr;
2267 if (lvalue->symtree->n.sym->ts.type == BT_UNKNOWN)
2269 gfc_error ("Pointer assignment target is not a POINTER at %L",
2274 if (lvalue->symtree->n.sym->attr.flavor == FL_PROCEDURE
2275 && lvalue->symtree->n.sym->attr.use_assoc)
2277 gfc_error ("'%s' in the pointer assignment at %L cannot be an "
2278 "l-value since it is a procedure",
2279 lvalue->symtree->n.sym->name, &lvalue->where);
2283 attr = gfc_variable_attr (lvalue, NULL);
2286 gfc_error ("Pointer assignment to non-POINTER at %L", &lvalue->where);
2290 is_pure = gfc_pure (NULL);
2292 if (is_pure && gfc_impure_variable (lvalue->symtree->n.sym))
2294 gfc_error ("Bad pointer object in PURE procedure at %L",
2299 /* If rvalue is a NULL() or NULLIFY, we're done. Otherwise the type,
2300 kind, etc for lvalue and rvalue must match, and rvalue must be a
2301 pure variable if we're in a pure function. */
2302 if (rvalue->expr_type == EXPR_NULL && rvalue->ts.type == BT_UNKNOWN)
2305 if (!gfc_compare_types (&lvalue->ts, &rvalue->ts))
2307 gfc_error ("Different types in pointer assignment at %L",
2312 if (lvalue->ts.kind != rvalue->ts.kind)
2314 gfc_error ("Different kind type parameters in pointer "
2315 "assignment at %L", &lvalue->where);
2319 if (lvalue->rank != rvalue->rank)
2321 gfc_error ("Different ranks in pointer assignment at %L",
2326 /* Now punt if we are dealing with a NULLIFY(X) or X = NULL(X). */
2327 if (rvalue->expr_type == EXPR_NULL)
2330 if (lvalue->ts.type == BT_CHARACTER
2331 && lvalue->ts.cl->length && rvalue->ts.cl->length
2332 && abs (gfc_dep_compare_expr (lvalue->ts.cl->length,
2333 rvalue->ts.cl->length)) == 1)
2335 gfc_error ("Different character lengths in pointer "
2336 "assignment at %L", &lvalue->where);
2340 attr = gfc_expr_attr (rvalue);
2341 if (!attr.target && !attr.pointer)
2343 gfc_error ("Pointer assignment target is neither TARGET "
2344 "nor POINTER at %L", &rvalue->where);
2348 if (is_pure && gfc_impure_variable (rvalue->symtree->n.sym))
2350 gfc_error ("Bad target in pointer assignment in PURE "
2351 "procedure at %L", &rvalue->where);
2354 if (gfc_has_vector_index (rvalue))
2356 gfc_error ("Pointer assignment with vector subscript "
2357 "on rhs at %L", &rvalue->where);
2365 /* Relative of gfc_check_assign() except that the lvalue is a single
2366 symbol. Used for initialization assignments. */
2369 gfc_check_assign_symbol (gfc_symbol * sym, gfc_expr * rvalue)
2374 memset (&lvalue, '\0', sizeof (gfc_expr));
2376 lvalue.expr_type = EXPR_VARIABLE;
2377 lvalue.ts = sym->ts;
2379 lvalue.rank = sym->as->rank;
2380 lvalue.symtree = (gfc_symtree *)gfc_getmem (sizeof (gfc_symtree));
2381 lvalue.symtree->n.sym = sym;
2382 lvalue.where = sym->declared_at;
2384 if (sym->attr.pointer)
2385 r = gfc_check_pointer_assign (&lvalue, rvalue);
2387 r = gfc_check_assign (&lvalue, rvalue, 1);
2389 gfc_free (lvalue.symtree);
2395 /* Get an expression for a default initializer. */
2398 gfc_default_initializer (gfc_typespec *ts)
2400 gfc_constructor *tail;
2406 /* See if we have a default initializer. */
2407 for (c = ts->derived->components; c; c = c->next)
2409 if ((c->initializer || c->allocatable) && init == NULL)
2410 init = gfc_get_expr ();
2416 /* Build the constructor. */
2417 init->expr_type = EXPR_STRUCTURE;
2419 init->where = ts->derived->declared_at;
2421 for (c = ts->derived->components; c; c = c->next)
2424 init->value.constructor = tail = gfc_get_constructor ();
2427 tail->next = gfc_get_constructor ();
2432 tail->expr = gfc_copy_expr (c->initializer);
2436 tail->expr = gfc_get_expr ();
2437 tail->expr->expr_type = EXPR_NULL;
2438 tail->expr->ts = c->ts;
2445 /* Given a symbol, create an expression node with that symbol as a
2446 variable. If the symbol is array valued, setup a reference of the
2450 gfc_get_variable_expr (gfc_symtree * var)
2454 e = gfc_get_expr ();
2455 e->expr_type = EXPR_VARIABLE;
2457 e->ts = var->n.sym->ts;
2459 if (var->n.sym->as != NULL)
2461 e->rank = var->n.sym->as->rank;
2462 e->ref = gfc_get_ref ();
2463 e->ref->type = REF_ARRAY;
2464 e->ref->u.ar.type = AR_FULL;
2471 /* Traverse expr, marking all EXPR_VARIABLE symbols referenced. */
2474 gfc_expr_set_symbols_referenced (gfc_expr * expr)
2476 gfc_actual_arglist *arg;
2483 switch (expr->expr_type)
2486 gfc_expr_set_symbols_referenced (expr->value.op.op1);
2487 gfc_expr_set_symbols_referenced (expr->value.op.op2);
2491 for (arg = expr->value.function.actual; arg; arg = arg->next)
2492 gfc_expr_set_symbols_referenced (arg->expr);
2496 gfc_set_sym_referenced (expr->symtree->n.sym);
2501 case EXPR_SUBSTRING:
2504 case EXPR_STRUCTURE:
2506 for (c = expr->value.constructor; c; c = c->next)
2507 gfc_expr_set_symbols_referenced (c->expr);
2515 for (ref = expr->ref; ref; ref = ref->next)
2519 for (i = 0; i < ref->u.ar.dimen; i++)
2521 gfc_expr_set_symbols_referenced (ref->u.ar.start[i]);
2522 gfc_expr_set_symbols_referenced (ref->u.ar.end[i]);
2523 gfc_expr_set_symbols_referenced (ref->u.ar.stride[i]);
2531 gfc_expr_set_symbols_referenced (ref->u.ss.start);
2532 gfc_expr_set_symbols_referenced (ref->u.ss.end);