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6de9cd9a | 1 | /* Deal with interfaces. |
ec378180 | 2 | Copyright (C) 2000, 2001, 2002, 2004, 2005 Free Software Foundation, Inc. |
6de9cd9a DN |
3 | Contributed by Andy Vaught |
4 | ||
9fc4d79b | 5 | This file is part of GCC. |
6de9cd9a | 6 | |
9fc4d79b TS |
7 | GCC is free software; you can redistribute it and/or modify it under |
8 | the terms of the GNU General Public License as published by the Free | |
9 | Software Foundation; either version 2, or (at your option) any later | |
10 | version. | |
6de9cd9a | 11 | |
9fc4d79b TS |
12 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY |
13 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
14 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
15 | for more details. | |
6de9cd9a DN |
16 | |
17 | You should have received a copy of the GNU General Public License | |
9fc4d79b TS |
18 | along with GCC; see the file COPYING. If not, write to the Free |
19 | Software Foundation, 59 Temple Place - Suite 330, Boston, MA | |
20 | 02111-1307, USA. */ | |
6de9cd9a DN |
21 | |
22 | ||
23 | /* Deal with interfaces. An explicit interface is represented as a | |
24 | singly linked list of formal argument structures attached to the | |
25 | relevant symbols. For an implicit interface, the arguments don't | |
26 | point to symbols. Explicit interfaces point to namespaces that | |
27 | contain the symbols within that interface. | |
28 | ||
29 | Implicit interfaces are linked together in a singly linked list | |
30 | along the next_if member of symbol nodes. Since a particular | |
31 | symbol can only have a single explicit interface, the symbol cannot | |
32 | be part of multiple lists and a single next-member suffices. | |
33 | ||
34 | This is not the case for general classes, though. An operator | |
35 | definition is independent of just about all other uses and has it's | |
36 | own head pointer. | |
37 | ||
38 | Nameless interfaces: | |
39 | Nameless interfaces create symbols with explicit interfaces within | |
40 | the current namespace. They are otherwise unlinked. | |
41 | ||
42 | Generic interfaces: | |
43 | The generic name points to a linked list of symbols. Each symbol | |
44 | has an explicit interface. Each explicit interface has it's own | |
45 | namespace containing the arguments. Module procedures are symbols in | |
46 | which the interface is added later when the module procedure is parsed. | |
47 | ||
48 | User operators: | |
49 | User-defined operators are stored in a their own set of symtrees | |
50 | separate from regular symbols. The symtrees point to gfc_user_op | |
51 | structures which in turn head up a list of relevant interfaces. | |
52 | ||
53 | Extended intrinsics and assignment: | |
54 | The head of these interface lists are stored in the containing namespace. | |
55 | ||
56 | Implicit interfaces: | |
57 | An implicit interface is represented as a singly linked list of | |
58 | formal argument list structures that don't point to any symbol | |
59 | nodes -- they just contain types. | |
60 | ||
61 | ||
62 | When a subprogram is defined, the program unit's name points to an | |
63 | interface as usual, but the link to the namespace is NULL and the | |
64 | formal argument list points to symbols within the same namespace as | |
65 | the program unit name. */ | |
66 | ||
67 | #include "config.h" | |
d22e4895 | 68 | #include "system.h" |
6de9cd9a DN |
69 | #include "gfortran.h" |
70 | #include "match.h" | |
71 | ||
72 | ||
73 | /* The current_interface structure holds information about the | |
74 | interface currently being parsed. This structure is saved and | |
75 | restored during recursive interfaces. */ | |
76 | ||
77 | gfc_interface_info current_interface; | |
78 | ||
79 | ||
80 | /* Free a singly linked list of gfc_interface structures. */ | |
81 | ||
82 | void | |
83 | gfc_free_interface (gfc_interface * intr) | |
84 | { | |
85 | gfc_interface *next; | |
86 | ||
87 | for (; intr; intr = next) | |
88 | { | |
89 | next = intr->next; | |
90 | gfc_free (intr); | |
91 | } | |
92 | } | |
93 | ||
94 | ||
95 | /* Change the operators unary plus and minus into binary plus and | |
96 | minus respectively, leaving the rest unchanged. */ | |
97 | ||
98 | static gfc_intrinsic_op | |
99 | fold_unary (gfc_intrinsic_op operator) | |
100 | { | |
101 | ||
102 | switch (operator) | |
103 | { | |
104 | case INTRINSIC_UPLUS: | |
105 | operator = INTRINSIC_PLUS; | |
106 | break; | |
107 | case INTRINSIC_UMINUS: | |
108 | operator = INTRINSIC_MINUS; | |
109 | break; | |
110 | default: | |
111 | break; | |
112 | } | |
113 | ||
114 | return operator; | |
115 | } | |
116 | ||
117 | ||
118 | /* Match a generic specification. Depending on which type of | |
119 | interface is found, the 'name' or 'operator' pointers may be set. | |
120 | This subroutine doesn't return MATCH_NO. */ | |
121 | ||
122 | match | |
123 | gfc_match_generic_spec (interface_type * type, | |
124 | char *name, | |
125 | gfc_intrinsic_op *operator) | |
126 | { | |
127 | char buffer[GFC_MAX_SYMBOL_LEN + 1]; | |
128 | match m; | |
129 | gfc_intrinsic_op i; | |
130 | ||
131 | if (gfc_match (" assignment ( = )") == MATCH_YES) | |
132 | { | |
133 | *type = INTERFACE_INTRINSIC_OP; | |
134 | *operator = INTRINSIC_ASSIGN; | |
135 | return MATCH_YES; | |
136 | } | |
137 | ||
138 | if (gfc_match (" operator ( %o )", &i) == MATCH_YES) | |
139 | { /* Operator i/f */ | |
140 | *type = INTERFACE_INTRINSIC_OP; | |
141 | *operator = fold_unary (i); | |
142 | return MATCH_YES; | |
143 | } | |
144 | ||
145 | if (gfc_match (" operator ( ") == MATCH_YES) | |
146 | { | |
147 | m = gfc_match_defined_op_name (buffer, 1); | |
148 | if (m == MATCH_NO) | |
149 | goto syntax; | |
150 | if (m != MATCH_YES) | |
151 | return MATCH_ERROR; | |
152 | ||
153 | m = gfc_match_char (')'); | |
154 | if (m == MATCH_NO) | |
155 | goto syntax; | |
156 | if (m != MATCH_YES) | |
157 | return MATCH_ERROR; | |
158 | ||
159 | strcpy (name, buffer); | |
160 | *type = INTERFACE_USER_OP; | |
161 | return MATCH_YES; | |
162 | } | |
163 | ||
164 | if (gfc_match_name (buffer) == MATCH_YES) | |
165 | { | |
166 | strcpy (name, buffer); | |
167 | *type = INTERFACE_GENERIC; | |
168 | return MATCH_YES; | |
169 | } | |
170 | ||
171 | *type = INTERFACE_NAMELESS; | |
172 | return MATCH_YES; | |
173 | ||
174 | syntax: | |
175 | gfc_error ("Syntax error in generic specification at %C"); | |
176 | return MATCH_ERROR; | |
177 | } | |
178 | ||
179 | ||
180 | /* Match one of the five forms of an interface statement. */ | |
181 | ||
182 | match | |
183 | gfc_match_interface (void) | |
184 | { | |
185 | char name[GFC_MAX_SYMBOL_LEN + 1]; | |
186 | interface_type type; | |
187 | gfc_symbol *sym; | |
188 | gfc_intrinsic_op operator; | |
189 | match m; | |
190 | ||
191 | m = gfc_match_space (); | |
192 | ||
193 | if (gfc_match_generic_spec (&type, name, &operator) == MATCH_ERROR) | |
194 | return MATCH_ERROR; | |
195 | ||
196 | ||
197 | /* If we're not looking at the end of the statement now, or if this | |
198 | is not a nameless interface but we did not see a space, punt. */ | |
199 | if (gfc_match_eos () != MATCH_YES | |
200 | || (type != INTERFACE_NAMELESS | |
201 | && m != MATCH_YES)) | |
202 | { | |
203 | gfc_error | |
204 | ("Syntax error: Trailing garbage in INTERFACE statement at %C"); | |
205 | return MATCH_ERROR; | |
206 | } | |
207 | ||
208 | current_interface.type = type; | |
209 | ||
210 | switch (type) | |
211 | { | |
212 | case INTERFACE_GENERIC: | |
213 | if (gfc_get_symbol (name, NULL, &sym)) | |
214 | return MATCH_ERROR; | |
215 | ||
231b2fcc TS |
216 | if (!sym->attr.generic |
217 | && gfc_add_generic (&sym->attr, sym->name, NULL) == FAILURE) | |
6de9cd9a DN |
218 | return MATCH_ERROR; |
219 | ||
220 | current_interface.sym = gfc_new_block = sym; | |
221 | break; | |
222 | ||
223 | case INTERFACE_USER_OP: | |
224 | current_interface.uop = gfc_get_uop (name); | |
225 | break; | |
226 | ||
227 | case INTERFACE_INTRINSIC_OP: | |
228 | current_interface.op = operator; | |
229 | break; | |
230 | ||
231 | case INTERFACE_NAMELESS: | |
232 | break; | |
233 | } | |
234 | ||
235 | return MATCH_YES; | |
236 | } | |
237 | ||
238 | ||
239 | /* Match the different sort of generic-specs that can be present after | |
240 | the END INTERFACE itself. */ | |
241 | ||
242 | match | |
243 | gfc_match_end_interface (void) | |
244 | { | |
245 | char name[GFC_MAX_SYMBOL_LEN + 1]; | |
246 | interface_type type; | |
247 | gfc_intrinsic_op operator; | |
248 | match m; | |
249 | ||
250 | m = gfc_match_space (); | |
251 | ||
252 | if (gfc_match_generic_spec (&type, name, &operator) == MATCH_ERROR) | |
253 | return MATCH_ERROR; | |
254 | ||
255 | /* If we're not looking at the end of the statement now, or if this | |
256 | is not a nameless interface but we did not see a space, punt. */ | |
257 | if (gfc_match_eos () != MATCH_YES | |
258 | || (type != INTERFACE_NAMELESS | |
259 | && m != MATCH_YES)) | |
260 | { | |
261 | gfc_error | |
262 | ("Syntax error: Trailing garbage in END INTERFACE statement at %C"); | |
263 | return MATCH_ERROR; | |
264 | } | |
265 | ||
266 | m = MATCH_YES; | |
267 | ||
268 | switch (current_interface.type) | |
269 | { | |
270 | case INTERFACE_NAMELESS: | |
271 | if (type != current_interface.type) | |
272 | { | |
273 | gfc_error ("Expected a nameless interface at %C"); | |
274 | m = MATCH_ERROR; | |
275 | } | |
276 | ||
277 | break; | |
278 | ||
279 | case INTERFACE_INTRINSIC_OP: | |
280 | if (type != current_interface.type || operator != current_interface.op) | |
281 | { | |
282 | ||
283 | if (current_interface.op == INTRINSIC_ASSIGN) | |
284 | gfc_error ("Expected 'END INTERFACE ASSIGNMENT (=)' at %C"); | |
285 | else | |
286 | gfc_error ("Expecting 'END INTERFACE OPERATOR (%s)' at %C", | |
287 | gfc_op2string (current_interface.op)); | |
288 | ||
289 | m = MATCH_ERROR; | |
290 | } | |
291 | ||
292 | break; | |
293 | ||
294 | case INTERFACE_USER_OP: | |
295 | /* Comparing the symbol node names is OK because only use-associated | |
296 | symbols can be renamed. */ | |
297 | if (type != current_interface.type | |
298 | || strcmp (current_interface.sym->name, name) != 0) | |
299 | { | |
300 | gfc_error ("Expecting 'END INTERFACE OPERATOR (.%s.)' at %C", | |
301 | current_interface.sym->name); | |
302 | m = MATCH_ERROR; | |
303 | } | |
304 | ||
305 | break; | |
306 | ||
307 | case INTERFACE_GENERIC: | |
308 | if (type != current_interface.type | |
309 | || strcmp (current_interface.sym->name, name) != 0) | |
310 | { | |
311 | gfc_error ("Expecting 'END INTERFACE %s' at %C", | |
312 | current_interface.sym->name); | |
313 | m = MATCH_ERROR; | |
314 | } | |
315 | ||
316 | break; | |
317 | } | |
318 | ||
319 | return m; | |
320 | } | |
321 | ||
322 | ||
323 | /* Compare two typespecs, recursively if necessary. */ | |
324 | ||
325 | int | |
326 | gfc_compare_types (gfc_typespec * ts1, gfc_typespec * ts2) | |
327 | { | |
328 | gfc_component *dt1, *dt2; | |
329 | ||
330 | if (ts1->type != ts2->type) | |
331 | return 0; | |
332 | if (ts1->type != BT_DERIVED) | |
333 | return (ts1->kind == ts2->kind); | |
334 | ||
335 | /* Compare derived types. */ | |
336 | if (ts1->derived == ts2->derived) | |
337 | return 1; | |
338 | ||
339 | /* Special case for comparing derived types across namespaces. If the | |
340 | true names and module names are the same and the module name is | |
341 | nonnull, then they are equal. */ | |
342 | if (strcmp (ts1->derived->name, ts2->derived->name) == 0 | |
343 | && ts1->derived->module[0] != '\0' | |
344 | && strcmp (ts1->derived->module, ts2->derived->module) == 0) | |
345 | return 1; | |
346 | ||
347 | /* Compare type via the rules of the standard. Both types must have | |
348 | the SEQUENCE attribute to be equal. */ | |
349 | ||
350 | if (strcmp (ts1->derived->name, ts2->derived->name)) | |
351 | return 0; | |
352 | ||
353 | dt1 = ts1->derived->components; | |
354 | dt2 = ts2->derived->components; | |
355 | ||
356 | if (ts1->derived->attr.sequence == 0 || ts2->derived->attr.sequence == 0) | |
357 | return 0; | |
358 | ||
359 | /* Since subtypes of SEQUENCE types must be SEQUENCE types as well, a | |
360 | simple test can speed things up. Otherwise, lots of things have to | |
361 | match. */ | |
362 | for (;;) | |
363 | { | |
364 | if (strcmp (dt1->name, dt2->name) != 0) | |
365 | return 0; | |
366 | ||
367 | if (dt1->pointer != dt2->pointer) | |
368 | return 0; | |
369 | ||
370 | if (dt1->dimension != dt2->dimension) | |
371 | return 0; | |
372 | ||
373 | if (dt1->dimension && gfc_compare_array_spec (dt1->as, dt2->as) == 0) | |
374 | return 0; | |
375 | ||
376 | if (gfc_compare_types (&dt1->ts, &dt2->ts) == 0) | |
377 | return 0; | |
378 | ||
379 | dt1 = dt1->next; | |
380 | dt2 = dt2->next; | |
381 | ||
382 | if (dt1 == NULL && dt2 == NULL) | |
383 | break; | |
384 | if (dt1 == NULL || dt2 == NULL) | |
385 | return 0; | |
386 | } | |
387 | ||
388 | return 1; | |
389 | } | |
390 | ||
391 | ||
392 | /* Given two symbols that are formal arguments, compare their ranks | |
393 | and types. Returns nonzero if they have the same rank and type, | |
394 | zero otherwise. */ | |
395 | ||
396 | static int | |
397 | compare_type_rank (gfc_symbol * s1, gfc_symbol * s2) | |
398 | { | |
399 | int r1, r2; | |
400 | ||
401 | r1 = (s1->as != NULL) ? s1->as->rank : 0; | |
402 | r2 = (s2->as != NULL) ? s2->as->rank : 0; | |
403 | ||
404 | if (r1 != r2) | |
405 | return 0; /* Ranks differ */ | |
406 | ||
407 | return gfc_compare_types (&s1->ts, &s2->ts); | |
408 | } | |
409 | ||
410 | ||
411 | static int compare_interfaces (gfc_symbol *, gfc_symbol *, int); | |
412 | ||
413 | /* Given two symbols that are formal arguments, compare their types | |
414 | and rank and their formal interfaces if they are both dummy | |
415 | procedures. Returns nonzero if the same, zero if different. */ | |
416 | ||
417 | static int | |
418 | compare_type_rank_if (gfc_symbol * s1, gfc_symbol * s2) | |
419 | { | |
420 | ||
421 | if (s1->attr.flavor != FL_PROCEDURE && s2->attr.flavor != FL_PROCEDURE) | |
422 | return compare_type_rank (s1, s2); | |
423 | ||
424 | if (s1->attr.flavor != FL_PROCEDURE || s2->attr.flavor != FL_PROCEDURE) | |
425 | return 0; | |
426 | ||
427 | /* At this point, both symbols are procedures. */ | |
428 | if ((s1->attr.function == 0 && s1->attr.subroutine == 0) | |
429 | || (s2->attr.function == 0 && s2->attr.subroutine == 0)) | |
430 | return 0; | |
431 | ||
432 | if (s1->attr.function != s2->attr.function | |
433 | || s1->attr.subroutine != s2->attr.subroutine) | |
434 | return 0; | |
435 | ||
436 | if (s1->attr.function && compare_type_rank (s1, s2) == 0) | |
437 | return 0; | |
438 | ||
439 | return compare_interfaces (s1, s2, 0); /* Recurse! */ | |
440 | } | |
441 | ||
442 | ||
443 | /* Given a formal argument list and a keyword name, search the list | |
444 | for that keyword. Returns the correct symbol node if found, NULL | |
445 | if not found. */ | |
446 | ||
447 | static gfc_symbol * | |
448 | find_keyword_arg (const char *name, gfc_formal_arglist * f) | |
449 | { | |
450 | ||
451 | for (; f; f = f->next) | |
452 | if (strcmp (f->sym->name, name) == 0) | |
453 | return f->sym; | |
454 | ||
455 | return NULL; | |
456 | } | |
457 | ||
458 | ||
459 | /******** Interface checking subroutines **********/ | |
460 | ||
461 | ||
462 | /* Given an operator interface and the operator, make sure that all | |
463 | interfaces for that operator are legal. */ | |
464 | ||
465 | static void | |
466 | check_operator_interface (gfc_interface * intr, gfc_intrinsic_op operator) | |
467 | { | |
468 | gfc_formal_arglist *formal; | |
469 | sym_intent i1, i2; | |
470 | gfc_symbol *sym; | |
471 | bt t1, t2; | |
472 | int args; | |
473 | ||
474 | if (intr == NULL) | |
475 | return; | |
476 | ||
477 | args = 0; | |
478 | t1 = t2 = BT_UNKNOWN; | |
479 | i1 = i2 = INTENT_UNKNOWN; | |
480 | ||
481 | for (formal = intr->sym->formal; formal; formal = formal->next) | |
482 | { | |
483 | sym = formal->sym; | |
484 | ||
485 | if (args == 0) | |
486 | { | |
487 | t1 = sym->ts.type; | |
488 | i1 = sym->attr.intent; | |
489 | } | |
490 | if (args == 1) | |
491 | { | |
492 | t2 = sym->ts.type; | |
493 | i2 = sym->attr.intent; | |
494 | } | |
495 | args++; | |
496 | } | |
497 | ||
498 | if (args == 0 || args > 2) | |
499 | goto num_args; | |
500 | ||
501 | sym = intr->sym; | |
502 | ||
503 | if (operator == INTRINSIC_ASSIGN) | |
504 | { | |
505 | if (!sym->attr.subroutine) | |
506 | { | |
507 | gfc_error | |
508 | ("Assignment operator interface at %L must be a SUBROUTINE", | |
509 | &intr->where); | |
510 | return; | |
511 | } | |
512 | } | |
513 | else | |
514 | { | |
515 | if (!sym->attr.function) | |
516 | { | |
517 | gfc_error ("Intrinsic operator interface at %L must be a FUNCTION", | |
518 | &intr->where); | |
519 | return; | |
520 | } | |
521 | } | |
522 | ||
523 | switch (operator) | |
524 | { | |
525 | case INTRINSIC_PLUS: /* Numeric unary or binary */ | |
526 | case INTRINSIC_MINUS: | |
527 | if ((args == 1) | |
528 | && (t1 == BT_INTEGER | |
529 | || t1 == BT_REAL | |
530 | || t1 == BT_COMPLEX)) | |
531 | goto bad_repl; | |
532 | ||
533 | if ((args == 2) | |
534 | && (t1 == BT_INTEGER || t1 == BT_REAL || t1 == BT_COMPLEX) | |
535 | && (t2 == BT_INTEGER || t2 == BT_REAL || t2 == BT_COMPLEX)) | |
536 | goto bad_repl; | |
537 | ||
538 | break; | |
539 | ||
540 | case INTRINSIC_POWER: /* Binary numeric */ | |
541 | case INTRINSIC_TIMES: | |
542 | case INTRINSIC_DIVIDE: | |
543 | ||
544 | case INTRINSIC_EQ: | |
545 | case INTRINSIC_NE: | |
546 | if (args == 1) | |
547 | goto num_args; | |
548 | ||
549 | if ((t1 == BT_INTEGER || t1 == BT_REAL || t1 == BT_COMPLEX) | |
550 | && (t2 == BT_INTEGER || t2 == BT_REAL || t2 == BT_COMPLEX)) | |
551 | goto bad_repl; | |
552 | ||
553 | break; | |
554 | ||
555 | case INTRINSIC_GE: /* Binary numeric operators that do not support */ | |
556 | case INTRINSIC_LE: /* complex numbers */ | |
557 | case INTRINSIC_LT: | |
558 | case INTRINSIC_GT: | |
559 | if (args == 1) | |
560 | goto num_args; | |
561 | ||
562 | if ((t1 == BT_INTEGER || t1 == BT_REAL) | |
563 | && (t2 == BT_INTEGER || t2 == BT_REAL)) | |
564 | goto bad_repl; | |
565 | ||
566 | break; | |
567 | ||
568 | case INTRINSIC_OR: /* Binary logical */ | |
569 | case INTRINSIC_AND: | |
570 | case INTRINSIC_EQV: | |
571 | case INTRINSIC_NEQV: | |
572 | if (args == 1) | |
573 | goto num_args; | |
574 | if (t1 == BT_LOGICAL && t2 == BT_LOGICAL) | |
575 | goto bad_repl; | |
576 | break; | |
577 | ||
578 | case INTRINSIC_NOT: /* Unary logical */ | |
579 | if (args != 1) | |
580 | goto num_args; | |
581 | if (t1 == BT_LOGICAL) | |
582 | goto bad_repl; | |
583 | break; | |
584 | ||
585 | case INTRINSIC_CONCAT: /* Binary string */ | |
586 | if (args != 2) | |
587 | goto num_args; | |
588 | if (t1 == BT_CHARACTER && t2 == BT_CHARACTER) | |
589 | goto bad_repl; | |
590 | break; | |
591 | ||
592 | case INTRINSIC_ASSIGN: /* Class by itself */ | |
593 | if (args != 2) | |
594 | goto num_args; | |
595 | break; | |
596 | default: | |
597 | gfc_internal_error ("check_operator_interface(): Bad operator"); | |
598 | } | |
599 | ||
600 | /* Check intents on operator interfaces. */ | |
601 | if (operator == INTRINSIC_ASSIGN) | |
602 | { | |
603 | if (i1 != INTENT_OUT && i1 != INTENT_INOUT) | |
604 | gfc_error ("First argument of defined assignment at %L must be " | |
605 | "INTENT(IN) or INTENT(INOUT)", &intr->where); | |
606 | ||
607 | if (i2 != INTENT_IN) | |
608 | gfc_error ("Second argument of defined assignment at %L must be " | |
609 | "INTENT(IN)", &intr->where); | |
610 | } | |
611 | else | |
612 | { | |
613 | if (i1 != INTENT_IN) | |
614 | gfc_error ("First argument of operator interface at %L must be " | |
615 | "INTENT(IN)", &intr->where); | |
616 | ||
617 | if (args == 2 && i2 != INTENT_IN) | |
618 | gfc_error ("Second argument of operator interface at %L must be " | |
619 | "INTENT(IN)", &intr->where); | |
620 | } | |
621 | ||
622 | return; | |
623 | ||
624 | bad_repl: | |
625 | gfc_error ("Operator interface at %L conflicts with intrinsic interface", | |
626 | &intr->where); | |
627 | return; | |
628 | ||
629 | num_args: | |
630 | gfc_error ("Operator interface at %L has the wrong number of arguments", | |
631 | &intr->where); | |
632 | return; | |
633 | } | |
634 | ||
635 | ||
636 | /* Given a pair of formal argument lists, we see if the two lists can | |
637 | be distinguished by counting the number of nonoptional arguments of | |
638 | a given type/rank in f1 and seeing if there are less then that | |
639 | number of those arguments in f2 (including optional arguments). | |
640 | Since this test is asymmetric, it has to be called twice to make it | |
641 | symmetric. Returns nonzero if the argument lists are incompatible | |
642 | by this test. This subroutine implements rule 1 of section | |
643 | 14.1.2.3. */ | |
644 | ||
645 | static int | |
646 | count_types_test (gfc_formal_arglist * f1, gfc_formal_arglist * f2) | |
647 | { | |
648 | int rc, ac1, ac2, i, j, k, n1; | |
649 | gfc_formal_arglist *f; | |
650 | ||
651 | typedef struct | |
652 | { | |
653 | int flag; | |
654 | gfc_symbol *sym; | |
655 | } | |
656 | arginfo; | |
657 | ||
658 | arginfo *arg; | |
659 | ||
660 | n1 = 0; | |
661 | ||
662 | for (f = f1; f; f = f->next) | |
663 | n1++; | |
664 | ||
665 | /* Build an array of integers that gives the same integer to | |
666 | arguments of the same type/rank. */ | |
667 | arg = gfc_getmem (n1 * sizeof (arginfo)); | |
668 | ||
669 | f = f1; | |
670 | for (i = 0; i < n1; i++, f = f->next) | |
671 | { | |
672 | arg[i].flag = -1; | |
673 | arg[i].sym = f->sym; | |
674 | } | |
675 | ||
676 | k = 0; | |
677 | ||
678 | for (i = 0; i < n1; i++) | |
679 | { | |
680 | if (arg[i].flag != -1) | |
681 | continue; | |
682 | ||
683 | if (arg[i].sym->attr.optional) | |
684 | continue; /* Skip optional arguments */ | |
685 | ||
686 | arg[i].flag = k; | |
687 | ||
688 | /* Find other nonoptional arguments of the same type/rank. */ | |
689 | for (j = i + 1; j < n1; j++) | |
690 | if (!arg[j].sym->attr.optional | |
691 | && compare_type_rank_if (arg[i].sym, arg[j].sym)) | |
692 | arg[j].flag = k; | |
693 | ||
694 | k++; | |
695 | } | |
696 | ||
697 | /* Now loop over each distinct type found in f1. */ | |
698 | k = 0; | |
699 | rc = 0; | |
700 | ||
701 | for (i = 0; i < n1; i++) | |
702 | { | |
703 | if (arg[i].flag != k) | |
704 | continue; | |
705 | ||
706 | ac1 = 1; | |
707 | for (j = i + 1; j < n1; j++) | |
708 | if (arg[j].flag == k) | |
709 | ac1++; | |
710 | ||
711 | /* Count the number of arguments in f2 with that type, including | |
f7b529fa | 712 | those that are optional. */ |
6de9cd9a DN |
713 | ac2 = 0; |
714 | ||
715 | for (f = f2; f; f = f->next) | |
716 | if (compare_type_rank_if (arg[i].sym, f->sym)) | |
717 | ac2++; | |
718 | ||
719 | if (ac1 > ac2) | |
720 | { | |
721 | rc = 1; | |
722 | break; | |
723 | } | |
724 | ||
725 | k++; | |
726 | } | |
727 | ||
728 | gfc_free (arg); | |
729 | ||
730 | return rc; | |
731 | } | |
732 | ||
733 | ||
734 | /* Perform the abbreviated correspondence test for operators. The | |
735 | arguments cannot be optional and are always ordered correctly, | |
736 | which makes this test much easier than that for generic tests. | |
737 | ||
738 | This subroutine is also used when comparing a formal and actual | |
739 | argument list when an actual parameter is a dummy procedure. At | |
740 | that point, two formal interfaces must be compared for equality | |
741 | which is what happens here. */ | |
742 | ||
743 | static int | |
744 | operator_correspondence (gfc_formal_arglist * f1, gfc_formal_arglist * f2) | |
745 | { | |
746 | for (;;) | |
747 | { | |
748 | if (f1 == NULL && f2 == NULL) | |
749 | break; | |
750 | if (f1 == NULL || f2 == NULL) | |
751 | return 1; | |
752 | ||
753 | if (!compare_type_rank (f1->sym, f2->sym)) | |
754 | return 1; | |
755 | ||
756 | f1 = f1->next; | |
757 | f2 = f2->next; | |
758 | } | |
759 | ||
760 | return 0; | |
761 | } | |
762 | ||
763 | ||
764 | /* Perform the correspondence test in rule 2 of section 14.1.2.3. | |
765 | Returns zero if no argument is found that satisifes rule 2, nonzero | |
766 | otherwise. | |
767 | ||
768 | This test is also not symmetric in f1 and f2 and must be called | |
769 | twice. This test finds problems caused by sorting the actual | |
770 | argument list with keywords. For example: | |
771 | ||
772 | INTERFACE FOO | |
773 | SUBROUTINE F1(A, B) | |
774 | INTEGER :: A ; REAL :: B | |
775 | END SUBROUTINE F1 | |
776 | ||
777 | SUBROUTINE F2(B, A) | |
778 | INTEGER :: A ; REAL :: B | |
779 | END SUBROUTINE F1 | |
780 | END INTERFACE FOO | |
781 | ||
782 | At this point, 'CALL FOO(A=1, B=1.0)' is ambiguous. */ | |
783 | ||
784 | static int | |
785 | generic_correspondence (gfc_formal_arglist * f1, gfc_formal_arglist * f2) | |
786 | { | |
787 | ||
788 | gfc_formal_arglist *f2_save, *g; | |
789 | gfc_symbol *sym; | |
790 | ||
791 | f2_save = f2; | |
792 | ||
793 | while (f1) | |
794 | { | |
795 | if (f1->sym->attr.optional) | |
796 | goto next; | |
797 | ||
798 | if (f2 != NULL && compare_type_rank (f1->sym, f2->sym)) | |
799 | goto next; | |
800 | ||
801 | /* Now search for a disambiguating keyword argument starting at | |
802 | the current non-match. */ | |
803 | for (g = f1; g; g = g->next) | |
804 | { | |
805 | if (g->sym->attr.optional) | |
806 | continue; | |
807 | ||
808 | sym = find_keyword_arg (g->sym->name, f2_save); | |
809 | if (sym == NULL || !compare_type_rank (g->sym, sym)) | |
810 | return 1; | |
811 | } | |
812 | ||
813 | next: | |
814 | f1 = f1->next; | |
815 | if (f2 != NULL) | |
816 | f2 = f2->next; | |
817 | } | |
818 | ||
819 | return 0; | |
820 | } | |
821 | ||
822 | ||
823 | /* 'Compare' two formal interfaces associated with a pair of symbols. | |
824 | We return nonzero if there exists an actual argument list that | |
825 | would be ambiguous between the two interfaces, zero otherwise. */ | |
826 | ||
827 | static int | |
828 | compare_interfaces (gfc_symbol * s1, gfc_symbol * s2, int generic_flag) | |
829 | { | |
830 | gfc_formal_arglist *f1, *f2; | |
831 | ||
832 | if (s1->attr.function != s2->attr.function | |
833 | && s1->attr.subroutine != s2->attr.subroutine) | |
834 | return 0; /* disagreement between function/subroutine */ | |
835 | ||
836 | f1 = s1->formal; | |
837 | f2 = s2->formal; | |
838 | ||
839 | if (f1 == NULL && f2 == NULL) | |
840 | return 1; /* Special case */ | |
841 | ||
842 | if (count_types_test (f1, f2)) | |
843 | return 0; | |
844 | if (count_types_test (f2, f1)) | |
845 | return 0; | |
846 | ||
847 | if (generic_flag) | |
848 | { | |
849 | if (generic_correspondence (f1, f2)) | |
850 | return 0; | |
851 | if (generic_correspondence (f2, f1)) | |
852 | return 0; | |
853 | } | |
854 | else | |
855 | { | |
856 | if (operator_correspondence (f1, f2)) | |
857 | return 0; | |
858 | } | |
859 | ||
860 | return 1; | |
861 | } | |
862 | ||
863 | ||
864 | /* Given a pointer to an interface pointer, remove duplicate | |
865 | interfaces and make sure that all symbols are either functions or | |
866 | subroutines. Returns nonzero if something goes wrong. */ | |
867 | ||
868 | static int | |
869 | check_interface0 (gfc_interface * p, const char *interface_name) | |
870 | { | |
871 | gfc_interface *psave, *q, *qlast; | |
872 | ||
873 | psave = p; | |
874 | /* Make sure all symbols in the interface have been defined as | |
875 | functions or subroutines. */ | |
876 | for (; p; p = p->next) | |
877 | if (!p->sym->attr.function && !p->sym->attr.subroutine) | |
878 | { | |
879 | gfc_error ("Procedure '%s' in %s at %L is neither function nor " | |
880 | "subroutine", p->sym->name, interface_name, | |
881 | &p->sym->declared_at); | |
882 | return 1; | |
883 | } | |
884 | p = psave; | |
885 | ||
886 | /* Remove duplicate interfaces in this interface list. */ | |
887 | for (; p; p = p->next) | |
888 | { | |
889 | qlast = p; | |
890 | ||
891 | for (q = p->next; q;) | |
892 | { | |
893 | if (p->sym != q->sym) | |
894 | { | |
895 | qlast = q; | |
896 | q = q->next; | |
897 | ||
898 | } | |
899 | else | |
900 | { | |
901 | /* Duplicate interface */ | |
902 | qlast->next = q->next; | |
903 | gfc_free (q); | |
904 | q = qlast->next; | |
905 | } | |
906 | } | |
907 | } | |
908 | ||
909 | return 0; | |
910 | } | |
911 | ||
912 | ||
913 | /* Check lists of interfaces to make sure that no two interfaces are | |
914 | ambiguous. Duplicate interfaces (from the same symbol) are OK | |
915 | here. */ | |
916 | ||
917 | static int | |
918 | check_interface1 (gfc_interface * p, gfc_interface * q, | |
919 | int generic_flag, const char *interface_name) | |
920 | { | |
921 | ||
922 | for (; p; p = p->next) | |
923 | for (; q; q = q->next) | |
924 | { | |
925 | if (p->sym == q->sym) | |
926 | continue; /* Duplicates OK here */ | |
927 | ||
928 | if (strcmp (p->sym->name, q->sym->name) == 0 | |
929 | && strcmp (p->sym->module, q->sym->module) == 0) | |
930 | continue; | |
931 | ||
932 | if (compare_interfaces (p->sym, q->sym, generic_flag)) | |
933 | { | |
934 | gfc_error ("Ambiguous interfaces '%s' and '%s' in %s at %L", | |
935 | p->sym->name, q->sym->name, interface_name, &p->where); | |
936 | return 1; | |
937 | } | |
938 | } | |
939 | ||
940 | return 0; | |
941 | } | |
942 | ||
943 | ||
944 | /* Check the generic and operator interfaces of symbols to make sure | |
945 | that none of the interfaces conflict. The check has to be done | |
946 | after all of the symbols are actually loaded. */ | |
947 | ||
948 | static void | |
949 | check_sym_interfaces (gfc_symbol * sym) | |
950 | { | |
951 | char interface_name[100]; | |
952 | gfc_symbol *s2; | |
953 | ||
954 | if (sym->ns != gfc_current_ns) | |
955 | return; | |
956 | ||
957 | if (sym->generic != NULL) | |
958 | { | |
959 | sprintf (interface_name, "generic interface '%s'", sym->name); | |
960 | if (check_interface0 (sym->generic, interface_name)) | |
961 | return; | |
962 | ||
963 | s2 = sym; | |
964 | while (s2 != NULL) | |
965 | { | |
966 | if (check_interface1 (sym->generic, s2->generic, 1, interface_name)) | |
967 | return; | |
968 | ||
969 | if (s2->ns->parent == NULL) | |
970 | break; | |
971 | if (gfc_find_symbol (sym->name, s2->ns->parent, 1, &s2)) | |
972 | break; | |
973 | } | |
974 | } | |
975 | } | |
976 | ||
977 | ||
978 | static void | |
979 | check_uop_interfaces (gfc_user_op * uop) | |
980 | { | |
981 | char interface_name[100]; | |
982 | gfc_user_op *uop2; | |
983 | gfc_namespace *ns; | |
984 | ||
985 | sprintf (interface_name, "operator interface '%s'", uop->name); | |
986 | if (check_interface0 (uop->operator, interface_name)) | |
987 | return; | |
988 | ||
989 | for (ns = gfc_current_ns; ns; ns = ns->parent) | |
990 | { | |
991 | uop2 = gfc_find_uop (uop->name, ns); | |
992 | if (uop2 == NULL) | |
993 | continue; | |
994 | ||
995 | check_interface1 (uop->operator, uop2->operator, 0, interface_name); | |
996 | } | |
997 | } | |
998 | ||
999 | ||
1000 | /* For the namespace, check generic, user operator and intrinsic | |
1001 | operator interfaces for consistency and to remove duplicate | |
1002 | interfaces. We traverse the whole namespace, counting on the fact | |
1003 | that most symbols will not have generic or operator interfaces. */ | |
1004 | ||
1005 | void | |
1006 | gfc_check_interfaces (gfc_namespace * ns) | |
1007 | { | |
1008 | gfc_namespace *old_ns, *ns2; | |
1009 | char interface_name[100]; | |
1010 | gfc_intrinsic_op i; | |
1011 | ||
1012 | old_ns = gfc_current_ns; | |
1013 | gfc_current_ns = ns; | |
1014 | ||
1015 | gfc_traverse_ns (ns, check_sym_interfaces); | |
1016 | ||
1017 | gfc_traverse_user_op (ns, check_uop_interfaces); | |
1018 | ||
1019 | for (i = GFC_INTRINSIC_BEGIN; i != GFC_INTRINSIC_END; i++) | |
1020 | { | |
1021 | if (i == INTRINSIC_USER) | |
1022 | continue; | |
1023 | ||
1024 | if (i == INTRINSIC_ASSIGN) | |
1025 | strcpy (interface_name, "intrinsic assignment operator"); | |
1026 | else | |
1027 | sprintf (interface_name, "intrinsic '%s' operator", | |
1028 | gfc_op2string (i)); | |
1029 | ||
1030 | if (check_interface0 (ns->operator[i], interface_name)) | |
1031 | continue; | |
1032 | ||
1033 | check_operator_interface (ns->operator[i], i); | |
1034 | ||
1035 | for (ns2 = ns->parent; ns2; ns2 = ns2->parent) | |
1036 | if (check_interface1 (ns->operator[i], ns2->operator[i], 0, | |
1037 | interface_name)) | |
1038 | break; | |
1039 | } | |
1040 | ||
1041 | gfc_current_ns = old_ns; | |
1042 | } | |
1043 | ||
1044 | ||
1045 | static int | |
1046 | symbol_rank (gfc_symbol * sym) | |
1047 | { | |
1048 | ||
1049 | return (sym->as == NULL) ? 0 : sym->as->rank; | |
1050 | } | |
1051 | ||
1052 | ||
1053 | /* Given a symbol of a formal argument list and an expression, if the | |
1054 | formal argument is a pointer, see if the actual argument is a | |
1055 | pointer. Returns nonzero if compatible, zero if not compatible. */ | |
1056 | ||
1057 | static int | |
1058 | compare_pointer (gfc_symbol * formal, gfc_expr * actual) | |
1059 | { | |
1060 | symbol_attribute attr; | |
1061 | ||
1062 | if (formal->attr.pointer) | |
1063 | { | |
1064 | attr = gfc_expr_attr (actual); | |
1065 | if (!attr.pointer) | |
1066 | return 0; | |
1067 | } | |
1068 | ||
1069 | return 1; | |
1070 | } | |
1071 | ||
1072 | ||
1073 | /* Given a symbol of a formal argument list and an expression, see if | |
1074 | the two are compatible as arguments. Returns nonzero if | |
1075 | compatible, zero if not compatible. */ | |
1076 | ||
1077 | static int | |
1078 | compare_parameter (gfc_symbol * formal, gfc_expr * actual, | |
1079 | int ranks_must_agree, int is_elemental) | |
1080 | { | |
1081 | gfc_ref *ref; | |
1082 | ||
1083 | if (actual->ts.type == BT_PROCEDURE) | |
1084 | { | |
1085 | if (formal->attr.flavor != FL_PROCEDURE) | |
1086 | return 0; | |
1087 | ||
1088 | if (formal->attr.function | |
1089 | && !compare_type_rank (formal, actual->symtree->n.sym)) | |
1090 | return 0; | |
1091 | ||
1092 | if (formal->attr.if_source == IFSRC_UNKNOWN) | |
1093 | return 1; /* Assume match */ | |
1094 | ||
1095 | return compare_interfaces (formal, actual->symtree->n.sym, 0); | |
1096 | } | |
1097 | ||
1600fe22 TS |
1098 | if (actual->expr_type != EXPR_NULL |
1099 | && !gfc_compare_types (&formal->ts, &actual->ts)) | |
6de9cd9a DN |
1100 | return 0; |
1101 | ||
1102 | if (symbol_rank (formal) == actual->rank) | |
1103 | return 1; | |
1104 | ||
1105 | /* At this point the ranks didn't agree. */ | |
1106 | if (ranks_must_agree || formal->attr.pointer) | |
1107 | return 0; | |
1108 | ||
1109 | if (actual->rank != 0) | |
1110 | return is_elemental || formal->attr.dimension; | |
1111 | ||
1112 | /* At this point, we are considering a scalar passed to an array. | |
1113 | This is legal if the scalar is an array element of the right sort. */ | |
1114 | if (formal->as->type == AS_ASSUMED_SHAPE) | |
1115 | return 0; | |
1116 | ||
1117 | for (ref = actual->ref; ref; ref = ref->next) | |
1118 | if (ref->type == REF_SUBSTRING) | |
1119 | return 0; | |
1120 | ||
1121 | for (ref = actual->ref; ref; ref = ref->next) | |
1122 | if (ref->type == REF_ARRAY && ref->u.ar.type == AR_ELEMENT) | |
1123 | break; | |
1124 | ||
1125 | if (ref == NULL) | |
1126 | return 0; /* Not an array element */ | |
1127 | ||
1128 | return 1; | |
1129 | } | |
1130 | ||
1131 | ||
1132 | /* Given formal and actual argument lists, see if they are compatible. | |
1133 | If they are compatible, the actual argument list is sorted to | |
1134 | correspond with the formal list, and elements for missing optional | |
1135 | arguments are inserted. If WHERE pointer is nonnull, then we issue | |
1136 | errors when things don't match instead of just returning the status | |
1137 | code. */ | |
1138 | ||
1139 | static int | |
1140 | compare_actual_formal (gfc_actual_arglist ** ap, | |
1141 | gfc_formal_arglist * formal, | |
1142 | int ranks_must_agree, int is_elemental, locus * where) | |
1143 | { | |
1144 | gfc_actual_arglist **new, *a, *actual, temp; | |
1145 | gfc_formal_arglist *f; | |
1146 | int i, n, na; | |
1147 | ||
1148 | actual = *ap; | |
1149 | ||
1150 | if (actual == NULL && formal == NULL) | |
1151 | return 1; | |
1152 | ||
1153 | n = 0; | |
1154 | for (f = formal; f; f = f->next) | |
1155 | n++; | |
1156 | ||
1157 | new = (gfc_actual_arglist **) alloca (n * sizeof (gfc_actual_arglist *)); | |
1158 | ||
1159 | for (i = 0; i < n; i++) | |
1160 | new[i] = NULL; | |
1161 | ||
1162 | na = 0; | |
1163 | f = formal; | |
1164 | i = 0; | |
1165 | ||
1166 | for (a = actual; a; a = a->next, f = f->next) | |
1167 | { | |
1168 | if (a->name[0] != '\0') | |
1169 | { | |
1170 | i = 0; | |
1171 | for (f = formal; f; f = f->next, i++) | |
1172 | { | |
1173 | if (f->sym == NULL) | |
1174 | continue; | |
1175 | if (strcmp (f->sym->name, a->name) == 0) | |
1176 | break; | |
1177 | } | |
1178 | ||
1179 | if (f == NULL) | |
1180 | { | |
1181 | if (where) | |
1182 | gfc_error | |
1183 | ("Keyword argument '%s' at %L is not in the procedure", | |
1184 | a->name, &a->expr->where); | |
1185 | return 0; | |
1186 | } | |
1187 | ||
1188 | if (new[i] != NULL) | |
1189 | { | |
1190 | if (where) | |
1191 | gfc_error | |
1192 | ("Keyword argument '%s' at %L is already associated " | |
1193 | "with another actual argument", a->name, &a->expr->where); | |
1194 | return 0; | |
1195 | } | |
1196 | } | |
1197 | ||
1198 | if (f == NULL) | |
1199 | { | |
1200 | if (where) | |
1201 | gfc_error | |
1202 | ("More actual than formal arguments in procedure call at %L", | |
1203 | where); | |
1204 | ||
1205 | return 0; | |
1206 | } | |
1207 | ||
1208 | if (f->sym == NULL && a->expr == NULL) | |
1209 | goto match; | |
1210 | ||
1211 | if (f->sym == NULL) | |
1212 | { | |
1213 | if (where) | |
1214 | gfc_error | |
1215 | ("Missing alternate return spec in subroutine call at %L", | |
1216 | where); | |
1217 | return 0; | |
1218 | } | |
1219 | ||
1220 | if (a->expr == NULL) | |
1221 | { | |
1222 | if (where) | |
1223 | gfc_error | |
1224 | ("Unexpected alternate return spec in subroutine call at %L", | |
1225 | where); | |
1226 | return 0; | |
1227 | } | |
1228 | ||
1229 | if (!compare_parameter | |
1230 | (f->sym, a->expr, ranks_must_agree, is_elemental)) | |
1231 | { | |
1232 | if (where) | |
1233 | gfc_error ("Type/rank mismatch in argument '%s' at %L", | |
1234 | f->sym->name, &a->expr->where); | |
1235 | return 0; | |
1236 | } | |
1237 | ||
1600fe22 TS |
1238 | if (a->expr->expr_type != EXPR_NULL |
1239 | && compare_pointer (f->sym, a->expr) == 0) | |
6de9cd9a DN |
1240 | { |
1241 | if (where) | |
1242 | gfc_error ("Actual argument for '%s' must be a pointer at %L", | |
1243 | f->sym->name, &a->expr->where); | |
1244 | return 0; | |
1245 | } | |
1246 | ||
1247 | match: | |
1248 | if (a == actual) | |
1249 | na = i; | |
1250 | ||
1251 | new[i++] = a; | |
1252 | } | |
1253 | ||
1254 | /* Make sure missing actual arguments are optional. */ | |
1255 | i = 0; | |
1256 | for (f = formal; f; f = f->next, i++) | |
1257 | { | |
1258 | if (new[i] != NULL) | |
1259 | continue; | |
1260 | if (!f->sym->attr.optional) | |
1261 | { | |
1262 | if (where) | |
1263 | gfc_error ("Missing actual argument for argument '%s' at %L", | |
1264 | f->sym->name, where); | |
1265 | return 0; | |
1266 | } | |
1267 | } | |
1268 | ||
1269 | /* The argument lists are compatible. We now relink a new actual | |
1270 | argument list with null arguments in the right places. The head | |
1271 | of the list remains the head. */ | |
1272 | for (i = 0; i < n; i++) | |
1273 | if (new[i] == NULL) | |
1274 | new[i] = gfc_get_actual_arglist (); | |
1275 | ||
1276 | if (na != 0) | |
1277 | { | |
1278 | temp = *new[0]; | |
1279 | *new[0] = *actual; | |
1280 | *actual = temp; | |
1281 | ||
1282 | a = new[0]; | |
1283 | new[0] = new[na]; | |
1284 | new[na] = a; | |
1285 | } | |
1286 | ||
1287 | for (i = 0; i < n - 1; i++) | |
1288 | new[i]->next = new[i + 1]; | |
1289 | ||
1290 | new[i]->next = NULL; | |
1291 | ||
1292 | if (*ap == NULL && n > 0) | |
1293 | *ap = new[0]; | |
1294 | ||
1600fe22 TS |
1295 | /* Note the types of omitted optional arguments. */ |
1296 | for (a = actual, f = formal; a; a = a->next, f = f->next) | |
1297 | if (a->expr == NULL && a->label == NULL) | |
1298 | a->missing_arg_type = f->sym->ts.type; | |
1299 | ||
6de9cd9a DN |
1300 | return 1; |
1301 | } | |
1302 | ||
1303 | ||
1304 | typedef struct | |
1305 | { | |
1306 | gfc_formal_arglist *f; | |
1307 | gfc_actual_arglist *a; | |
1308 | } | |
1309 | argpair; | |
1310 | ||
1311 | /* qsort comparison function for argument pairs, with the following | |
1312 | order: | |
1313 | - p->a->expr == NULL | |
1314 | - p->a->expr->expr_type != EXPR_VARIABLE | |
f7b529fa | 1315 | - growing p->a->expr->symbol. */ |
6de9cd9a DN |
1316 | |
1317 | static int | |
1318 | pair_cmp (const void *p1, const void *p2) | |
1319 | { | |
1320 | const gfc_actual_arglist *a1, *a2; | |
1321 | ||
1322 | /* *p1 and *p2 are elements of the to-be-sorted array. */ | |
1323 | a1 = ((const argpair *) p1)->a; | |
1324 | a2 = ((const argpair *) p2)->a; | |
1325 | if (!a1->expr) | |
1326 | { | |
1327 | if (!a2->expr) | |
1328 | return 0; | |
1329 | return -1; | |
1330 | } | |
1331 | if (!a2->expr) | |
1332 | return 1; | |
1333 | if (a1->expr->expr_type != EXPR_VARIABLE) | |
1334 | { | |
1335 | if (a2->expr->expr_type != EXPR_VARIABLE) | |
1336 | return 0; | |
1337 | return -1; | |
1338 | } | |
1339 | if (a2->expr->expr_type != EXPR_VARIABLE) | |
1340 | return 1; | |
1341 | return a1->expr->symtree->n.sym < a2->expr->symtree->n.sym; | |
1342 | } | |
1343 | ||
1344 | ||
1345 | /* Given two expressions from some actual arguments, test whether they | |
1346 | refer to the same expression. The analysis is conservative. | |
1347 | Returning FAILURE will produce no warning. */ | |
1348 | ||
1349 | static try | |
1350 | compare_actual_expr (gfc_expr * e1, gfc_expr * e2) | |
1351 | { | |
1352 | const gfc_ref *r1, *r2; | |
1353 | ||
1354 | if (!e1 || !e2 | |
1355 | || e1->expr_type != EXPR_VARIABLE | |
1356 | || e2->expr_type != EXPR_VARIABLE | |
1357 | || e1->symtree->n.sym != e2->symtree->n.sym) | |
1358 | return FAILURE; | |
1359 | ||
1360 | /* TODO: improve comparison, see expr.c:show_ref(). */ | |
1361 | for (r1 = e1->ref, r2 = e2->ref; r1 && r2; r1 = r1->next, r2 = r2->next) | |
1362 | { | |
1363 | if (r1->type != r2->type) | |
1364 | return FAILURE; | |
1365 | switch (r1->type) | |
1366 | { | |
1367 | case REF_ARRAY: | |
1368 | if (r1->u.ar.type != r2->u.ar.type) | |
1369 | return FAILURE; | |
1370 | /* TODO: At the moment, consider only full arrays; | |
1371 | we could do better. */ | |
1372 | if (r1->u.ar.type != AR_FULL || r2->u.ar.type != AR_FULL) | |
1373 | return FAILURE; | |
1374 | break; | |
1375 | ||
1376 | case REF_COMPONENT: | |
1377 | if (r1->u.c.component != r2->u.c.component) | |
1378 | return FAILURE; | |
1379 | break; | |
1380 | ||
1381 | case REF_SUBSTRING: | |
1382 | return FAILURE; | |
1383 | ||
1384 | default: | |
1385 | gfc_internal_error ("compare_actual_expr(): Bad component code"); | |
1386 | } | |
1387 | } | |
1388 | if (!r1 && !r2) | |
1389 | return SUCCESS; | |
1390 | return FAILURE; | |
1391 | } | |
1392 | ||
1393 | /* Given formal and actual argument lists that correspond to one | |
1394 | another, check that identical actual arguments aren't not | |
1395 | associated with some incompatible INTENTs. */ | |
1396 | ||
1397 | static try | |
1398 | check_some_aliasing (gfc_formal_arglist * f, gfc_actual_arglist * a) | |
1399 | { | |
1400 | sym_intent f1_intent, f2_intent; | |
1401 | gfc_formal_arglist *f1; | |
1402 | gfc_actual_arglist *a1; | |
1403 | size_t n, i, j; | |
1404 | argpair *p; | |
1405 | try t = SUCCESS; | |
1406 | ||
1407 | n = 0; | |
1408 | for (f1 = f, a1 = a;; f1 = f1->next, a1 = a1->next) | |
1409 | { | |
1410 | if (f1 == NULL && a1 == NULL) | |
1411 | break; | |
1412 | if (f1 == NULL || a1 == NULL) | |
1413 | gfc_internal_error ("check_some_aliasing(): List mismatch"); | |
1414 | n++; | |
1415 | } | |
1416 | if (n == 0) | |
1417 | return t; | |
1418 | p = (argpair *) alloca (n * sizeof (argpair)); | |
1419 | ||
1420 | for (i = 0, f1 = f, a1 = a; i < n; i++, f1 = f1->next, a1 = a1->next) | |
1421 | { | |
1422 | p[i].f = f1; | |
1423 | p[i].a = a1; | |
1424 | } | |
1425 | ||
1426 | qsort (p, n, sizeof (argpair), pair_cmp); | |
1427 | ||
1428 | for (i = 0; i < n; i++) | |
1429 | { | |
1430 | if (!p[i].a->expr | |
1431 | || p[i].a->expr->expr_type != EXPR_VARIABLE | |
1432 | || p[i].a->expr->ts.type == BT_PROCEDURE) | |
1433 | continue; | |
1434 | f1_intent = p[i].f->sym->attr.intent; | |
1435 | for (j = i + 1; j < n; j++) | |
1436 | { | |
1437 | /* Expected order after the sort. */ | |
1438 | if (!p[j].a->expr || p[j].a->expr->expr_type != EXPR_VARIABLE) | |
1439 | gfc_internal_error ("check_some_aliasing(): corrupted data"); | |
1440 | ||
1441 | /* Are the expression the same? */ | |
1442 | if (compare_actual_expr (p[i].a->expr, p[j].a->expr) == FAILURE) | |
1443 | break; | |
1444 | f2_intent = p[j].f->sym->attr.intent; | |
1445 | if ((f1_intent == INTENT_IN && f2_intent == INTENT_OUT) | |
1446 | || (f1_intent == INTENT_OUT && f2_intent == INTENT_IN)) | |
1447 | { | |
1448 | gfc_warning ("Same actual argument associated with INTENT(%s) " | |
1449 | "argument '%s' and INTENT(%s) argument '%s' at %L", | |
1450 | gfc_intent_string (f1_intent), p[i].f->sym->name, | |
1451 | gfc_intent_string (f2_intent), p[j].f->sym->name, | |
1452 | &p[i].a->expr->where); | |
1453 | t = FAILURE; | |
1454 | } | |
1455 | } | |
1456 | } | |
1457 | ||
1458 | return t; | |
1459 | } | |
1460 | ||
1461 | ||
1462 | /* Given formal and actual argument lists that correspond to one | |
1463 | another, check that they are compatible in the sense that intents | |
1464 | are not mismatched. */ | |
1465 | ||
1466 | static try | |
1467 | check_intents (gfc_formal_arglist * f, gfc_actual_arglist * a) | |
1468 | { | |
1469 | sym_intent a_intent, f_intent; | |
1470 | ||
1471 | for (;; f = f->next, a = a->next) | |
1472 | { | |
1473 | if (f == NULL && a == NULL) | |
1474 | break; | |
1475 | if (f == NULL || a == NULL) | |
1476 | gfc_internal_error ("check_intents(): List mismatch"); | |
1477 | ||
1478 | if (a->expr == NULL || a->expr->expr_type != EXPR_VARIABLE) | |
1479 | continue; | |
1480 | ||
1481 | a_intent = a->expr->symtree->n.sym->attr.intent; | |
1482 | f_intent = f->sym->attr.intent; | |
1483 | ||
1484 | if (a_intent == INTENT_IN | |
1485 | && (f_intent == INTENT_INOUT | |
1486 | || f_intent == INTENT_OUT)) | |
1487 | { | |
1488 | ||
1489 | gfc_error ("Procedure argument at %L is INTENT(IN) while interface " | |
1490 | "specifies INTENT(%s)", &a->expr->where, | |
1491 | gfc_intent_string (f_intent)); | |
1492 | return FAILURE; | |
1493 | } | |
1494 | ||
1495 | if (gfc_pure (NULL) && gfc_impure_variable (a->expr->symtree->n.sym)) | |
1496 | { | |
1497 | if (f_intent == INTENT_INOUT || f_intent == INTENT_OUT) | |
1498 | { | |
1499 | gfc_error | |
1500 | ("Procedure argument at %L is local to a PURE procedure and " | |
1501 | "is passed to an INTENT(%s) argument", &a->expr->where, | |
1502 | gfc_intent_string (f_intent)); | |
1503 | return FAILURE; | |
1504 | } | |
1505 | ||
1506 | if (a->expr->symtree->n.sym->attr.pointer) | |
1507 | { | |
1508 | gfc_error | |
1509 | ("Procedure argument at %L is local to a PURE procedure and " | |
1510 | "has the POINTER attribute", &a->expr->where); | |
1511 | return FAILURE; | |
1512 | } | |
1513 | } | |
1514 | } | |
1515 | ||
1516 | return SUCCESS; | |
1517 | } | |
1518 | ||
1519 | ||
1520 | /* Check how a procedure is used against its interface. If all goes | |
1521 | well, the actual argument list will also end up being properly | |
1522 | sorted. */ | |
1523 | ||
1524 | void | |
1525 | gfc_procedure_use (gfc_symbol * sym, gfc_actual_arglist ** ap, locus * where) | |
1526 | { | |
1527 | /* Warn about calls with an implicit interface. */ | |
1528 | if (gfc_option.warn_implicit_interface | |
1529 | && sym->attr.if_source == IFSRC_UNKNOWN) | |
1530 | gfc_warning ("Procedure '%s' called with an implicit interface at %L", | |
1531 | sym->name, where); | |
1532 | ||
1533 | if (sym->attr.if_source == IFSRC_UNKNOWN | |
1534 | || !compare_actual_formal (ap, sym->formal, 0, | |
1535 | sym->attr.elemental, where)) | |
1536 | return; | |
1537 | ||
1538 | check_intents (sym->formal, *ap); | |
1539 | if (gfc_option.warn_aliasing) | |
1540 | check_some_aliasing (sym->formal, *ap); | |
1541 | } | |
1542 | ||
1543 | ||
1544 | /* Given an interface pointer and an actual argument list, search for | |
1545 | a formal argument list that matches the actual. If found, returns | |
1546 | a pointer to the symbol of the correct interface. Returns NULL if | |
1547 | not found. */ | |
1548 | ||
1549 | gfc_symbol * | |
1550 | gfc_search_interface (gfc_interface * intr, int sub_flag, | |
1551 | gfc_actual_arglist ** ap) | |
1552 | { | |
1553 | int r; | |
1554 | ||
1555 | for (; intr; intr = intr->next) | |
1556 | { | |
1557 | if (sub_flag && intr->sym->attr.function) | |
1558 | continue; | |
1559 | if (!sub_flag && intr->sym->attr.subroutine) | |
1560 | continue; | |
1561 | ||
1562 | r = !intr->sym->attr.elemental; | |
1563 | ||
1564 | if (compare_actual_formal (ap, intr->sym->formal, r, !r, NULL)) | |
1565 | { | |
1566 | check_intents (intr->sym->formal, *ap); | |
1567 | if (gfc_option.warn_aliasing) | |
1568 | check_some_aliasing (intr->sym->formal, *ap); | |
1569 | return intr->sym; | |
1570 | } | |
1571 | } | |
1572 | ||
1573 | return NULL; | |
1574 | } | |
1575 | ||
1576 | ||
1577 | /* Do a brute force recursive search for a symbol. */ | |
1578 | ||
1579 | static gfc_symtree * | |
1580 | find_symtree0 (gfc_symtree * root, gfc_symbol * sym) | |
1581 | { | |
1582 | gfc_symtree * st; | |
1583 | ||
1584 | if (root->n.sym == sym) | |
1585 | return root; | |
1586 | ||
1587 | st = NULL; | |
1588 | if (root->left) | |
1589 | st = find_symtree0 (root->left, sym); | |
1590 | if (root->right && ! st) | |
1591 | st = find_symtree0 (root->right, sym); | |
1592 | return st; | |
1593 | } | |
1594 | ||
1595 | ||
1596 | /* Find a symtree for a symbol. */ | |
1597 | ||
1598 | static gfc_symtree * | |
1599 | find_sym_in_symtree (gfc_symbol * sym) | |
1600 | { | |
1601 | gfc_symtree *st; | |
1602 | gfc_namespace *ns; | |
1603 | ||
1604 | /* First try to find it by name. */ | |
1605 | gfc_find_sym_tree (sym->name, gfc_current_ns, 1, &st); | |
1606 | if (st && st->n.sym == sym) | |
1607 | return st; | |
1608 | ||
1609 | /* if it's been renamed, resort to a brute-force search. */ | |
1610 | /* TODO: avoid having to do this search. If the symbol doesn't exist | |
1611 | in the symtree for the current namespace, it should probably be added. */ | |
1612 | for (ns = gfc_current_ns; ns; ns = ns->parent) | |
1613 | { | |
1614 | st = find_symtree0 (ns->sym_root, sym); | |
1615 | if (st) | |
1616 | return st; | |
1617 | } | |
1618 | gfc_internal_error ("Unable to find symbol %s", sym->name); | |
1619 | /* Not reached */ | |
1620 | } | |
1621 | ||
1622 | ||
1623 | /* This subroutine is called when an expression is being resolved. | |
1624 | The expression node in question is either a user defined operator | |
1f2959f0 | 1625 | or an intrinsic operator with arguments that aren't compatible |
6de9cd9a DN |
1626 | with the operator. This subroutine builds an actual argument list |
1627 | corresponding to the operands, then searches for a compatible | |
1628 | interface. If one is found, the expression node is replaced with | |
1629 | the appropriate function call. */ | |
1630 | ||
1631 | try | |
1632 | gfc_extend_expr (gfc_expr * e) | |
1633 | { | |
1634 | gfc_actual_arglist *actual; | |
1635 | gfc_symbol *sym; | |
1636 | gfc_namespace *ns; | |
1637 | gfc_user_op *uop; | |
1638 | gfc_intrinsic_op i; | |
1639 | ||
1640 | sym = NULL; | |
1641 | ||
1642 | actual = gfc_get_actual_arglist (); | |
1643 | actual->expr = e->op1; | |
1644 | ||
1645 | if (e->op2 != NULL) | |
1646 | { | |
1647 | actual->next = gfc_get_actual_arglist (); | |
1648 | actual->next->expr = e->op2; | |
1649 | } | |
1650 | ||
1651 | i = fold_unary (e->operator); | |
1652 | ||
1653 | if (i == INTRINSIC_USER) | |
1654 | { | |
1655 | for (ns = gfc_current_ns; ns; ns = ns->parent) | |
1656 | { | |
1657 | uop = gfc_find_uop (e->uop->name, ns); | |
1658 | if (uop == NULL) | |
1659 | continue; | |
1660 | ||
1661 | sym = gfc_search_interface (uop->operator, 0, &actual); | |
1662 | if (sym != NULL) | |
1663 | break; | |
1664 | } | |
1665 | } | |
1666 | else | |
1667 | { | |
1668 | for (ns = gfc_current_ns; ns; ns = ns->parent) | |
1669 | { | |
1670 | sym = gfc_search_interface (ns->operator[i], 0, &actual); | |
1671 | if (sym != NULL) | |
1672 | break; | |
1673 | } | |
1674 | } | |
1675 | ||
1676 | if (sym == NULL) | |
1677 | { | |
1678 | /* Don't use gfc_free_actual_arglist() */ | |
1679 | if (actual->next != NULL) | |
1680 | gfc_free (actual->next); | |
1681 | gfc_free (actual); | |
1682 | ||
1683 | return FAILURE; | |
1684 | } | |
1685 | ||
1686 | /* Change the expression node to a function call. */ | |
1687 | e->expr_type = EXPR_FUNCTION; | |
1688 | e->symtree = find_sym_in_symtree (sym); | |
1689 | e->value.function.actual = actual; | |
1690 | ||
1691 | if (gfc_pure (NULL) && !gfc_pure (sym)) | |
1692 | { | |
1693 | gfc_error | |
1694 | ("Function '%s' called in lieu of an operator at %L must be PURE", | |
1695 | sym->name, &e->where); | |
1696 | return FAILURE; | |
1697 | } | |
1698 | ||
1699 | if (gfc_resolve_expr (e) == FAILURE) | |
1700 | return FAILURE; | |
1701 | ||
1702 | return SUCCESS; | |
1703 | } | |
1704 | ||
1705 | ||
1706 | /* Tries to replace an assignment code node with a subroutine call to | |
1707 | the subroutine associated with the assignment operator. Return | |
1708 | SUCCESS if the node was replaced. On FAILURE, no error is | |
1709 | generated. */ | |
1710 | ||
1711 | try | |
1712 | gfc_extend_assign (gfc_code * c, gfc_namespace * ns) | |
1713 | { | |
1714 | gfc_actual_arglist *actual; | |
1715 | gfc_expr *lhs, *rhs; | |
1716 | gfc_symbol *sym; | |
1717 | ||
1718 | lhs = c->expr; | |
1719 | rhs = c->expr2; | |
1720 | ||
1721 | /* Don't allow an intrinsic assignment to be replaced. */ | |
1722 | if (lhs->ts.type != BT_DERIVED && rhs->ts.type != BT_DERIVED | |
1723 | && (lhs->ts.type == rhs->ts.type | |
1724 | || (gfc_numeric_ts (&lhs->ts) | |
1725 | && gfc_numeric_ts (&rhs->ts)))) | |
1726 | return FAILURE; | |
1727 | ||
1728 | actual = gfc_get_actual_arglist (); | |
1729 | actual->expr = lhs; | |
1730 | ||
1731 | actual->next = gfc_get_actual_arglist (); | |
1732 | actual->next->expr = rhs; | |
1733 | ||
1734 | sym = NULL; | |
1735 | ||
1736 | for (; ns; ns = ns->parent) | |
1737 | { | |
1738 | sym = gfc_search_interface (ns->operator[INTRINSIC_ASSIGN], 1, &actual); | |
1739 | if (sym != NULL) | |
1740 | break; | |
1741 | } | |
1742 | ||
1743 | if (sym == NULL) | |
1744 | { | |
1745 | gfc_free (actual->next); | |
1746 | gfc_free (actual); | |
1747 | return FAILURE; | |
1748 | } | |
1749 | ||
1750 | /* Replace the assignment with the call. */ | |
1751 | c->op = EXEC_CALL; | |
1752 | c->symtree = find_sym_in_symtree (sym); | |
1753 | c->expr = NULL; | |
1754 | c->expr2 = NULL; | |
1755 | c->ext.actual = actual; | |
1756 | ||
1757 | if (gfc_pure (NULL) && !gfc_pure (sym)) | |
1758 | { | |
1759 | gfc_error ("Subroutine '%s' called in lieu of assignment at %L must be " | |
1760 | "PURE", sym->name, &c->loc); | |
1761 | return FAILURE; | |
1762 | } | |
1763 | ||
1764 | return SUCCESS; | |
1765 | } | |
1766 | ||
1767 | ||
1768 | /* Make sure that the interface just parsed is not already present in | |
1769 | the given interface list. Ambiguity isn't checked yet since module | |
1770 | procedures can be present without interfaces. */ | |
1771 | ||
1772 | static try | |
1773 | check_new_interface (gfc_interface * base, gfc_symbol * new) | |
1774 | { | |
1775 | gfc_interface *ip; | |
1776 | ||
1777 | for (ip = base; ip; ip = ip->next) | |
1778 | { | |
1779 | if (ip->sym == new) | |
1780 | { | |
1781 | gfc_error ("Entity '%s' at %C is already present in the interface", | |
1782 | new->name); | |
1783 | return FAILURE; | |
1784 | } | |
1785 | } | |
1786 | ||
1787 | return SUCCESS; | |
1788 | } | |
1789 | ||
1790 | ||
1791 | /* Add a symbol to the current interface. */ | |
1792 | ||
1793 | try | |
1794 | gfc_add_interface (gfc_symbol * new) | |
1795 | { | |
1796 | gfc_interface **head, *intr; | |
1797 | gfc_namespace *ns; | |
1798 | gfc_symbol *sym; | |
1799 | ||
1800 | switch (current_interface.type) | |
1801 | { | |
1802 | case INTERFACE_NAMELESS: | |
1803 | return SUCCESS; | |
1804 | ||
1805 | case INTERFACE_INTRINSIC_OP: | |
1806 | for (ns = current_interface.ns; ns; ns = ns->parent) | |
1807 | if (check_new_interface (ns->operator[current_interface.op], new) | |
1808 | == FAILURE) | |
1809 | return FAILURE; | |
1810 | ||
1811 | head = ¤t_interface.ns->operator[current_interface.op]; | |
1812 | break; | |
1813 | ||
1814 | case INTERFACE_GENERIC: | |
1815 | for (ns = current_interface.ns; ns; ns = ns->parent) | |
1816 | { | |
1817 | gfc_find_symbol (current_interface.sym->name, ns, 0, &sym); | |
1818 | if (sym == NULL) | |
1819 | continue; | |
1820 | ||
1821 | if (check_new_interface (sym->generic, new) == FAILURE) | |
1822 | return FAILURE; | |
1823 | } | |
1824 | ||
1825 | head = ¤t_interface.sym->generic; | |
1826 | break; | |
1827 | ||
1828 | case INTERFACE_USER_OP: | |
1829 | if (check_new_interface (current_interface.uop->operator, new) == | |
1830 | FAILURE) | |
1831 | return FAILURE; | |
1832 | ||
1833 | head = ¤t_interface.uop->operator; | |
1834 | break; | |
1835 | ||
1836 | default: | |
1837 | gfc_internal_error ("gfc_add_interface(): Bad interface type"); | |
1838 | } | |
1839 | ||
1840 | intr = gfc_get_interface (); | |
1841 | intr->sym = new; | |
63645982 | 1842 | intr->where = gfc_current_locus; |
6de9cd9a DN |
1843 | |
1844 | intr->next = *head; | |
1845 | *head = intr; | |
1846 | ||
1847 | return SUCCESS; | |
1848 | } | |
1849 | ||
1850 | ||
1851 | /* Gets rid of a formal argument list. We do not free symbols. | |
1852 | Symbols are freed when a namespace is freed. */ | |
1853 | ||
1854 | void | |
1855 | gfc_free_formal_arglist (gfc_formal_arglist * p) | |
1856 | { | |
1857 | gfc_formal_arglist *q; | |
1858 | ||
1859 | for (; p; p = q) | |
1860 | { | |
1861 | q = p->next; | |
1862 | gfc_free (p); | |
1863 | } | |
1864 | } |