1 /* $NetBSD: tree.c,v 1.59 2009/05/02 16:10:49 christos Exp $ */ 2 3 /* 4 * Copyright (c) 1994, 1995 Jochen Pohl 5 * All Rights Reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by Jochen Pohl for 18 * The NetBSD Project. 19 * 4. The name of the author may not be used to endorse or promote products 20 * derived from this software without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 23 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 24 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 25 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 26 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 27 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 28 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 29 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 30 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 31 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 32 */ 33 34 #if HAVE_NBTOOL_CONFIG_H 35 #include "nbtool_config.h" 36 #endif 37 38 #include <sys/cdefs.h> 39 #if defined(__RCSID) && !defined(lint) 40 __RCSID("$NetBSD: tree.c,v 1.59 2009/05/02 16:10:49 christos Exp $"); 41 #endif 42 43 #include <stdlib.h> 44 #include <string.h> 45 #include <float.h> 46 #include <limits.h> 47 #include <math.h> 48 #include <signal.h> 49 50 #include "lint1.h" 51 #include "cgram.h" 52 #include "externs1.h" 53 54 /* Various flags for each operator. */ 55 static mod_t modtab[NOPS]; 56 57 static tnode_t *getinode(tspec_t, int64_t); 58 static void ptrcmpok(op_t, tnode_t *, tnode_t *); 59 static int asgntypok(op_t, int, tnode_t *, tnode_t *); 60 static void chkbeop(op_t, tnode_t *, tnode_t *); 61 static void chkeop2(op_t, int, tnode_t *, tnode_t *); 62 static void chkeop1(op_t, int, tnode_t *, tnode_t *); 63 static tnode_t *mktnode(op_t, type_t *, tnode_t *, tnode_t *); 64 static void balance(op_t, tnode_t **, tnode_t **); 65 static void incompat(op_t, tspec_t, tspec_t); 66 static void illptrc(mod_t *, type_t *, type_t *); 67 static void mrgqual(type_t **, type_t *, type_t *); 68 static int conmemb(type_t *); 69 static void ptconv(int, tspec_t, tspec_t, type_t *, tnode_t *); 70 static void iiconv(op_t, int, tspec_t, tspec_t, type_t *, tnode_t *); 71 static void piconv(op_t, tspec_t, type_t *, tnode_t *); 72 static void ppconv(op_t, tnode_t *, type_t *); 73 static tnode_t *bldstr(op_t, tnode_t *, tnode_t *); 74 static tnode_t *bldincdec(op_t, tnode_t *); 75 static tnode_t *bldri(op_t, tnode_t *); 76 static tnode_t *bldamper(tnode_t *, int); 77 static tnode_t *bldplmi(op_t, tnode_t *, tnode_t *); 78 static tnode_t *bldshft(op_t, tnode_t *, tnode_t *); 79 static tnode_t *bldcol(tnode_t *, tnode_t *); 80 static tnode_t *bldasgn(op_t, tnode_t *, tnode_t *); 81 static tnode_t *plength(type_t *); 82 static tnode_t *fold(tnode_t *); 83 static tnode_t *foldtst(tnode_t *); 84 static tnode_t *foldflt(tnode_t *); 85 static tnode_t *chkfarg(type_t *, tnode_t *); 86 static tnode_t *parg(int, type_t *, tnode_t *); 87 static void nulleff(tnode_t *); 88 static void displexpr(tnode_t *, int); 89 static void chkaidx(tnode_t *, int); 90 static void chkcomp(op_t, tnode_t *, tnode_t *); 91 static void precconf(tnode_t *); 92 93 extern sig_atomic_t fpe; 94 95 /* 96 * Initialize mods of operators. 97 */ 98 void 99 initmtab(void) 100 { 101 static struct { 102 op_t op; 103 mod_t m; 104 } imods[] = { 105 { ARROW, { 1,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0, 106 "->" } }, 107 { POINT, { 1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 108 "." } }, 109 { NOT, { 0,1,0,1,0,1,0,1,0,0,0,0,0,0,0,1,0,0, 110 "!" } }, 111 { COMPL, { 0,0,0,0,0,1,1,0,0,0,0,0,0,0,0,1,1,1, 112 "~" } }, 113 { INCBEF, { 0,0,0,1,0,0,0,0,0,1,0,0,0,0,0,1,0,0, 114 "prefix++" } }, 115 { DECBEF, { 0,0,0,1,0,0,0,0,0,1,0,0,0,0,0,1,0,0, 116 "prefix--" } }, 117 { INCAFT, { 0,0,0,1,0,0,0,0,0,1,0,0,0,0,0,1,0,0, 118 "postfix++" } }, 119 { DECAFT, { 0,0,0,1,0,0,0,0,0,1,0,0,0,0,0,1,0,0, 120 "postfix--" } }, 121 { UPLUS, { 0,0,0,0,1,1,1,0,0,0,0,0,0,0,0,1,1,0, 122 "unary +" } }, 123 { UMINUS, { 0,0,0,0,1,1,1,0,0,0,1,0,0,0,0,1,1,0, 124 "unary -" } }, 125 { STAR, { 0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0, 126 "unary *" } }, 127 { AMPER, { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 128 "unary &" } }, 129 { MULT, { 1,0,0,0,1,1,1,0,1,0,0,1,0,0,0,1,1,0, 130 "*" } }, 131 { DIV, { 1,0,0,0,1,1,1,0,1,0,1,1,0,0,0,1,1,0, 132 "/" } }, 133 { MOD, { 1,0,1,0,0,1,1,0,1,0,1,1,0,0,0,1,1,0, 134 "%" } }, 135 { PLUS, { 1,0,0,1,0,1,1,0,1,0,0,0,0,0,0,1,0,0, 136 "+" } }, 137 { MINUS, { 1,0,0,1,0,1,1,0,1,0,0,0,0,0,0,1,0,0, 138 "-" } }, 139 { SHL, { 1,0,1,0,0,1,1,0,0,0,0,0,1,0,0,1,1,0, 140 "<<" } }, 141 { SHR, { 1,0,1,0,0,1,1,0,0,0,1,0,1,0,0,1,1,0, 142 ">>" } }, 143 { LT, { 1,1,0,1,0,1,1,0,1,0,1,1,0,1,1,0,1,0, 144 "<" } }, 145 { LE, { 1,1,0,1,0,1,1,0,1,0,1,1,0,1,1,0,1,0, 146 "<=" } }, 147 { GT, { 1,1,0,1,0,1,1,0,1,0,1,1,0,1,1,0,1,0, 148 ">" } }, 149 { GE, { 1,1,0,1,0,1,1,0,1,0,1,1,0,1,1,0,1,0, 150 ">=" } }, 151 { EQ, { 1,1,0,1,0,1,1,0,1,0,0,0,0,1,1,0,1,0, 152 "==" } }, 153 { NE, { 1,1,0,1,0,1,1,0,1,0,0,0,0,1,1,0,1,0, 154 "!=" } }, 155 { AND, { 1,0,1,0,0,1,1,0,1,0,0,0,1,0,0,1,0,0, 156 "&" } }, 157 { XOR, { 1,0,1,0,0,1,1,0,1,0,0,0,1,0,0,1,0,0, 158 "^" } }, 159 { OR, { 1,0,1,0,0,1,1,0,1,0,0,0,1,0,0,1,0,0, 160 "|" } }, 161 { LOGAND, { 1,1,0,1,0,1,0,1,0,0,0,0,0,0,0,1,0,0, 162 "&&" } }, 163 { LOGOR, { 1,1,0,1,0,1,0,1,0,0,0,0,1,0,0,1,0,0, 164 "||" } }, 165 { QUEST, { 1,0,0,0,0,1,0,1,0,0,0,0,0,0,0,0,0,0, 166 "?" } }, 167 { COLON, { 1,0,0,0,0,0,1,0,1,0,0,0,0,0,1,0,0,0, 168 ":" } }, 169 { ASSIGN, { 1,0,0,0,0,0,0,0,0,1,0,0,0,0,1,0,0,0, 170 "=" } }, 171 { MULASS, { 1,0,0,0,1,0,0,0,0,1,0,0,0,0,0,1,0,0, 172 "*=" } }, 173 { DIVASS, { 1,0,0,0,1,0,0,0,0,1,0,1,0,0,0,1,0,0, 174 "/=" } }, 175 { MODASS, { 1,0,1,0,0,0,0,0,0,1,0,1,0,0,0,1,0,0, 176 "%=" } }, 177 { ADDASS, { 1,0,0,1,0,0,0,0,0,1,0,0,0,0,0,1,0,0, 178 "+=" } }, 179 { SUBASS, { 1,0,0,1,0,0,0,0,0,1,0,0,0,0,0,1,0,0, 180 "-=" } }, 181 { SHLASS, { 1,0,1,0,0,0,0,0,0,1,0,0,0,0,0,1,0,0, 182 "<<=" } }, 183 { SHRASS, { 1,0,1,0,0,0,0,0,0,1,0,0,0,0,0,1,0,0, 184 ">>=" } }, 185 { ANDASS, { 1,0,1,0,0,0,0,0,0,1,0,0,0,0,0,1,0,0, 186 "&=" } }, 187 { XORASS, { 1,0,1,0,0,0,0,0,0,1,0,0,0,0,0,1,0,0, 188 "^=" } }, 189 { ORASS, { 1,0,1,0,0,0,0,0,0,1,0,0,0,0,0,1,0,0, 190 "|=" } }, 191 { NAME, { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 192 "NAME" } }, 193 { CON, { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 194 "CON" } }, 195 { STRING, { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 196 "STRING" } }, 197 { FSEL, { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 198 "FSEL" } }, 199 { CALL, { 1,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0, 200 "CALL" } }, 201 { COMMA, { 1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0, 202 "," } }, 203 { CVT, { 0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0, 204 "CVT" } }, 205 { ICALL, { 1,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0, 206 "ICALL" } }, 207 { LOAD, { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 208 "LOAD" } }, 209 { PUSH, { 0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0, 210 "PUSH" } }, 211 { RETURN, { 1,0,0,0,0,0,0,0,0,1,0,0,0,0,1,0,0,0, 212 "RETURN" } }, 213 { INIT, { 1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0, 214 "INIT" } }, 215 { FARG, { 1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0, 216 "FARG" } }, 217 { NOOP, { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, NULL } } 218 }; 219 int i; 220 221 for (i = 0; imods[i].op != NOOP; i++) 222 STRUCT_ASSIGN(modtab[imods[i].op], imods[i].m); 223 } 224 225 /* 226 * Increase degree of reference. 227 * This is most often used to change type "T" in type "pointer to T". 228 */ 229 type_t * 230 incref(type_t *tp, tspec_t t) 231 { 232 type_t *tp2; 233 234 tp2 = getblk(sizeof (type_t)); 235 tp2->t_tspec = t; 236 tp2->t_subt = tp; 237 return (tp2); 238 } 239 240 /* 241 * same for use in expressions 242 */ 243 type_t * 244 tincref(type_t *tp, tspec_t t) 245 { 246 type_t *tp2; 247 248 tp2 = tgetblk(sizeof (type_t)); 249 tp2->t_tspec = t; 250 tp2->t_subt = tp; 251 return (tp2); 252 } 253 254 /* 255 * Create a node for a constant. 256 */ 257 tnode_t * 258 getcnode(type_t *tp, val_t *v) 259 { 260 tnode_t *n; 261 262 n = getnode(); 263 n->tn_op = CON; 264 n->tn_type = tp; 265 n->tn_val = tgetblk(sizeof (val_t)); 266 n->tn_val->v_tspec = tp->t_tspec; 267 n->tn_val->v_ansiu = v->v_ansiu; 268 n->tn_val->v_u = v->v_u; 269 free(v); 270 return (n); 271 } 272 273 /* 274 * Create a node for a integer constant. 275 */ 276 static tnode_t * 277 getinode(tspec_t t, int64_t q) 278 { 279 tnode_t *n; 280 281 n = getnode(); 282 n->tn_op = CON; 283 n->tn_type = gettyp(t); 284 n->tn_val = tgetblk(sizeof (val_t)); 285 n->tn_val->v_tspec = t; 286 n->tn_val->v_quad = q; 287 return (n); 288 } 289 290 /* 291 * Create a node for a name (symbol table entry). 292 * ntok is the token which follows the name. 293 */ 294 tnode_t * 295 getnnode(sym_t *sym, int ntok) 296 { 297 tnode_t *n; 298 299 if (sym->s_scl == NOSCL) { 300 sym->s_scl = EXTERN; 301 sym->s_def = DECL; 302 if (ntok == T_LPARN) { 303 if (sflag) { 304 /* function implicitly declared to ... */ 305 warning(215); 306 } 307 /* 308 * XXX if tflag is set the symbol should be 309 * exported to level 0 310 */ 311 sym->s_type = incref(sym->s_type, FUNC); 312 } else { 313 if (!blklev) { 314 /* %s undefined */ 315 error(99, sym->s_name); 316 } else { 317 int fixtype; 318 if (strcmp(sym->s_name, "__FUNCTION__") == 0) { 319 gnuism(316); 320 fixtype = 1; 321 } else if (strcmp(sym->s_name, "__func__") == 0) { 322 if (!Sflag) 323 warning(317); 324 fixtype = 1; 325 } else { 326 error(99, sym->s_name); 327 fixtype = 0; 328 } 329 if (fixtype) { 330 sym->s_type = incref(gettyp(CHAR), PTR); 331 sym->s_type->t_const = 1; 332 } 333 } 334 } 335 } 336 337 if (sym->s_kind != FVFT && sym->s_kind != FMOS) 338 LERROR("getnnode()"); 339 340 n = getnode(); 341 n->tn_type = sym->s_type; 342 if (sym->s_scl != ENUMCON) { 343 n->tn_op = NAME; 344 n->tn_sym = sym; 345 if (sym->s_kind == FVFT && sym->s_type->t_tspec != FUNC) 346 n->tn_lvalue = 1; 347 } else { 348 n->tn_op = CON; 349 n->tn_val = tgetblk(sizeof (val_t)); 350 *n->tn_val = sym->s_value; 351 } 352 353 return (n); 354 } 355 356 /* 357 * Create a node for a string. 358 */ 359 tnode_t * 360 getsnode(strg_t *strg) 361 { 362 size_t len; 363 tnode_t *n; 364 365 len = strg->st_len; 366 367 n = getnode(); 368 369 n->tn_op = STRING; 370 n->tn_type = tincref(gettyp(strg->st_tspec), ARRAY); 371 n->tn_type->t_dim = len + 1; 372 n->tn_lvalue = 1; 373 374 n->tn_strg = tgetblk(sizeof (strg_t)); 375 n->tn_strg->st_tspec = strg->st_tspec; 376 n->tn_strg->st_len = len; 377 378 if (strg->st_tspec == CHAR) { 379 n->tn_strg->st_cp = tgetblk(len + 1); 380 (void)memcpy(n->tn_strg->st_cp, strg->st_cp, len + 1); 381 free(strg->st_cp); 382 } else { 383 n->tn_strg->st_wcp = tgetblk((len + 1) * sizeof (wchar_t)); 384 (void)memcpy(n->tn_strg->st_wcp, strg->st_wcp, 385 (len + 1) * sizeof (wchar_t)); 386 free(strg->st_wcp); 387 } 388 free(strg); 389 390 return (n); 391 } 392 393 /* 394 * Returns a symbol which has the same name as the msym argument and is a 395 * member of the struct or union specified by the tn argument. 396 */ 397 sym_t * 398 strmemb(tnode_t *tn, op_t op, sym_t *msym) 399 { 400 str_t *str; 401 type_t *tp; 402 sym_t *sym, *csym; 403 int eq; 404 tspec_t t; 405 406 /* 407 * Remove the member if it was unknown until now (Which means 408 * that no defined struct or union has a member with the same name). 409 */ 410 if (msym->s_scl == NOSCL) { 411 /* undefined struct/union member: %s */ 412 error(101, msym->s_name); 413 rmsym(msym); 414 msym->s_kind = FMOS; 415 msym->s_scl = MOS; 416 msym->s_styp = tgetblk(sizeof (str_t)); 417 msym->s_styp->stag = tgetblk(sizeof (sym_t)); 418 msym->s_styp->stag->s_name = unnamed; 419 msym->s_value.v_tspec = INT; 420 return (msym); 421 } 422 423 /* Set str to the tag of which msym is expected to be a member. */ 424 str = NULL; 425 t = (tp = tn->tn_type)->t_tspec; 426 if (op == POINT) { 427 if (t == STRUCT || t == UNION) 428 str = tp->t_str; 429 } else if (op == ARROW && t == PTR) { 430 t = (tp = tp->t_subt)->t_tspec; 431 if (t == STRUCT || t == UNION) 432 str = tp->t_str; 433 } 434 435 /* 436 * If this struct/union has a member with the name of msym, return 437 * return this it. 438 */ 439 if (str != NULL) { 440 for (sym = msym; sym != NULL; sym = sym->s_link) { 441 if (sym->s_scl != MOS && sym->s_scl != MOU) 442 continue; 443 if (sym->s_styp != str) 444 continue; 445 if (strcmp(sym->s_name, msym->s_name) != 0) 446 continue; 447 return (sym); 448 } 449 } 450 451 /* 452 * Set eq to 0 if there are struct/union members with the same name 453 * and different types and/or offsets. 454 */ 455 eq = 1; 456 for (csym = msym; csym != NULL; csym = csym->s_link) { 457 if (csym->s_scl != MOS && csym->s_scl != MOU) 458 continue; 459 if (strcmp(msym->s_name, csym->s_name) != 0) 460 continue; 461 for (sym = csym->s_link ; sym != NULL; sym = sym->s_link) { 462 int w; 463 464 if (sym->s_scl != MOS && sym->s_scl != MOU) 465 continue; 466 if (strcmp(csym->s_name, sym->s_name) != 0) 467 continue; 468 if (csym->s_value.v_quad != sym->s_value.v_quad) { 469 eq = 0; 470 break; 471 } 472 w = 0; 473 eq = eqtype(csym->s_type, sym->s_type, 0, 0, &w) && !w; 474 if (!eq) 475 break; 476 if (csym->s_field != sym->s_field) { 477 eq = 0; 478 break; 479 } 480 if (csym->s_field) { 481 type_t *tp1, *tp2; 482 483 tp1 = csym->s_type; 484 tp2 = sym->s_type; 485 if (tp1->t_flen != tp2->t_flen) { 486 eq = 0; 487 break; 488 } 489 if (tp1->t_foffs != tp2->t_foffs) { 490 eq = 0; 491 break; 492 } 493 } 494 } 495 if (!eq) 496 break; 497 } 498 499 /* 500 * Now handle the case in which the left operand refers really 501 * to a struct/union, but the right operand is not member of it. 502 */ 503 if (str != NULL) { 504 /* illegal member use: %s */ 505 if (eq && tflag) { 506 warning(102, msym->s_name); 507 } else { 508 error(102, msym->s_name); 509 } 510 return (msym); 511 } 512 513 /* 514 * Now the left operand of ARROW does not point to a struct/union 515 * or the left operand of POINT is no struct/union. 516 */ 517 if (eq) { 518 if (op == POINT) { 519 /* left operand of "." must be struct/union object */ 520 if (tflag) { 521 warning(103); 522 } else { 523 error(103); 524 } 525 } else { 526 /* left operand of "->" must be pointer to ... */ 527 if (tflag && tn->tn_type->t_tspec == PTR) { 528 warning(104); 529 } else { 530 error(104); 531 } 532 } 533 } else { 534 if (tflag) { 535 /* non-unique member requires struct/union %s */ 536 error(105, op == POINT ? "object" : "pointer"); 537 } else { 538 /* unacceptable operand of %s */ 539 error(111, modtab[op].m_name); 540 } 541 } 542 543 return (msym); 544 } 545 546 /* 547 * Create a tree node. Called for most operands except function calls, 548 * sizeof and casts. 549 * 550 * op operator 551 * ln left operand 552 * rn if not NULL, right operand 553 */ 554 tnode_t * 555 build(op_t op, tnode_t *ln, tnode_t *rn) 556 { 557 mod_t *mp; 558 tnode_t *ntn; 559 type_t *rtp; 560 561 mp = &modtab[op]; 562 563 /* If there was an error in one of the operands, return. */ 564 if (ln == NULL || (mp->m_binary && rn == NULL)) 565 return (NULL); 566 567 /* 568 * Apply class conversions to the left operand, but only if its 569 * value is needed or it is compaired with null. 570 */ 571 if (mp->m_vctx || mp->m_tctx) 572 ln = cconv(ln); 573 /* 574 * The right operand is almost always in a test or value context, 575 * except if it is a struct or union member. 576 */ 577 if (mp->m_binary && op != ARROW && op != POINT) 578 rn = cconv(rn); 579 580 /* 581 * Print some warnings for comparisons of unsigned values with 582 * constants lower than or equal to null. This must be done 583 * before promote() because otherwise unsigned char and unsigned 584 * short would be promoted to int. Also types are tested to be 585 * CHAR, which would also become int. 586 */ 587 if (mp->m_comp) 588 chkcomp(op, ln, rn); 589 590 /* 591 * Promote the left operand if it is in a test or value context 592 */ 593 if (mp->m_vctx || mp->m_tctx) 594 ln = promote(op, 0, ln); 595 /* 596 * Promote the right operand, but only if it is no struct or 597 * union member, or if it is not to be assigned to the left operand 598 */ 599 if (mp->m_binary && op != ARROW && op != POINT && 600 op != ASSIGN && op != RETURN) { 601 rn = promote(op, 0, rn); 602 } 603 604 /* 605 * If the result of the operation is different for signed or 606 * unsigned operands and one of the operands is signed only in 607 * ANSI C, print a warning. 608 */ 609 if (mp->m_tlansiu && ln->tn_op == CON && ln->tn_val->v_ansiu) { 610 /* ANSI C treats constant as unsigned, op %s */ 611 warning(218, mp->m_name); 612 ln->tn_val->v_ansiu = 0; 613 } 614 if (mp->m_transiu && rn->tn_op == CON && rn->tn_val->v_ansiu) { 615 /* ANSI C treats constant as unsigned, op %s */ 616 warning(218, mp->m_name); 617 rn->tn_val->v_ansiu = 0; 618 } 619 620 /* Make sure both operands are of the same type */ 621 if (mp->m_balance || (tflag && (op == SHL || op == SHR))) 622 balance(op, &ln, &rn); 623 624 /* 625 * Check types for compatibility with the operation and mutual 626 * compatibility. Return if there are serios problems. 627 */ 628 if (!typeok(op, 0, ln, rn)) 629 return (NULL); 630 631 /* And now create the node. */ 632 switch (op) { 633 case POINT: 634 case ARROW: 635 ntn = bldstr(op, ln, rn); 636 break; 637 case INCAFT: 638 case DECAFT: 639 case INCBEF: 640 case DECBEF: 641 ntn = bldincdec(op, ln); 642 break; 643 case AMPER: 644 ntn = bldamper(ln, 0); 645 break; 646 case STAR: 647 ntn = mktnode(STAR, ln->tn_type->t_subt, ln, NULL); 648 break; 649 case PLUS: 650 case MINUS: 651 ntn = bldplmi(op, ln, rn); 652 break; 653 case SHL: 654 case SHR: 655 ntn = bldshft(op, ln, rn); 656 break; 657 case COLON: 658 ntn = bldcol(ln, rn); 659 break; 660 case ASSIGN: 661 case MULASS: 662 case DIVASS: 663 case MODASS: 664 case ADDASS: 665 case SUBASS: 666 case SHLASS: 667 case SHRASS: 668 case ANDASS: 669 case XORASS: 670 case ORASS: 671 case RETURN: 672 ntn = bldasgn(op, ln, rn); 673 break; 674 case COMMA: 675 case QUEST: 676 ntn = mktnode(op, rn->tn_type, ln, rn); 677 break; 678 case REAL: 679 case IMAG: 680 ntn = bldri(op, ln); 681 break; 682 default: 683 rtp = mp->m_logop ? gettyp(INT) : ln->tn_type; 684 if (!mp->m_binary && rn != NULL) 685 LERROR("build()"); 686 ntn = mktnode(op, rtp, ln, rn); 687 break; 688 } 689 690 /* Return if an error occurred. */ 691 if (ntn == NULL) 692 return (NULL); 693 694 /* Print a warning if precedence confusion is possible */ 695 if (mp->m_tpconf) 696 precconf(ntn); 697 698 /* 699 * Print a warning if one of the operands is in a context where 700 * it is compared with null and if this operand is a constant. 701 */ 702 if (mp->m_tctx) { 703 if (ln->tn_op == CON || 704 ((mp->m_binary && op != QUEST) && rn->tn_op == CON)) { 705 if (hflag && !ccflg) 706 /* constant in conditional context */ 707 warning(161); 708 } 709 } 710 711 /* Fold if the operator requires it */ 712 if (mp->m_fold) { 713 if (ln->tn_op == CON && (!mp->m_binary || rn->tn_op == CON)) { 714 if (mp->m_tctx) { 715 ntn = foldtst(ntn); 716 } else if (isftyp(ntn->tn_type->t_tspec)) { 717 ntn = foldflt(ntn); 718 } else { 719 ntn = fold(ntn); 720 } 721 } else if (op == QUEST && ln->tn_op == CON) { 722 ntn = ln->tn_val->v_quad ? rn->tn_left : rn->tn_right; 723 } 724 } 725 726 return (ntn); 727 } 728 729 /* 730 * Perform class conversions. 731 * 732 * Arrays of type T are converted into pointers to type T. 733 * Functions are converted to pointers to functions. 734 * Lvalues are converted to rvalues. 735 */ 736 tnode_t * 737 cconv(tnode_t *tn) 738 { 739 type_t *tp; 740 741 /* 742 * Array-lvalue (array of type T) is converted into rvalue 743 * (pointer to type T) 744 */ 745 if (tn->tn_type->t_tspec == ARRAY) { 746 if (!tn->tn_lvalue) { 747 /* %soperand of '%s' must be lvalue */ 748 /* XXX print correct operator */ 749 (void)gnuism(114, "", modtab[AMPER].m_name); 750 } 751 tn = mktnode(AMPER, tincref(tn->tn_type->t_subt, PTR), 752 tn, NULL); 753 } 754 755 /* 756 * Expression of type function (function with return value of type T) 757 * in rvalue-expression (pointer to function with return value 758 * of type T) 759 */ 760 if (tn->tn_type->t_tspec == FUNC) 761 tn = bldamper(tn, 1); 762 763 /* lvalue to rvalue */ 764 if (tn->tn_lvalue) { 765 tp = tduptyp(tn->tn_type); 766 tp->t_const = tp->t_volatile = 0; 767 tn = mktnode(LOAD, tp, tn, NULL); 768 } 769 770 return (tn); 771 } 772 773 /* 774 * Perform most type checks. First the types are checked using 775 * informations from modtab[]. After that it is done by hand for 776 * more complicated operators and type combinations. 777 * 778 * If the types are ok, typeok() returns 1, otherwise 0. 779 */ 780 int 781 typeok(op_t op, int arg, tnode_t *ln, tnode_t *rn) 782 { 783 mod_t *mp; 784 tspec_t lt, rt = NOTSPEC, lst = NOTSPEC, rst = NOTSPEC, olt = NOTSPEC, 785 ort = NOTSPEC; 786 type_t *ltp, *rtp = NULL, *lstp = NULL, *rstp = NULL; 787 tnode_t *tn; 788 789 mp = &modtab[op]; 790 791 if ((ltp = ln->tn_type) == NULL) 792 LERROR("typeok()"); 793 794 if ((lt = ltp->t_tspec) == PTR) 795 lst = (lstp = ltp->t_subt)->t_tspec; 796 if (mp->m_binary) { 797 if ((rtp = rn->tn_type) == NULL) 798 LERROR("typeok()"); 799 if ((rt = rtp->t_tspec) == PTR) 800 rst = (rstp = rtp->t_subt)->t_tspec; 801 } 802 803 if (mp->m_rqint) { 804 /* integertypes required */ 805 if (!isityp(lt) || (mp->m_binary && !isityp(rt))) { 806 incompat(op, lt, rt); 807 return (0); 808 } 809 } else if (mp->m_rqintcomp) { 810 /* integertypes required */ 811 if ((!isityp(lt) && !isctyp(lt)) || 812 (mp->m_binary && (!isityp(rt) && !isctyp(rt)))) { 813 incompat(op, lt, rt); 814 return (0); 815 } 816 } else if (mp->m_rqsclt) { 817 /* scalar types required */ 818 if (!issclt(lt) || (mp->m_binary && !issclt(rt))) { 819 incompat(op, lt, rt); 820 return (0); 821 } 822 } else if (mp->m_rqatyp) { 823 /* arithmetic types required */ 824 if (!isatyp(lt) || (mp->m_binary && !isatyp(rt))) { 825 incompat(op, lt, rt); 826 return (0); 827 } 828 } 829 830 if (op == SHL || op == SHR || op == SHLASS || op == SHRASS) { 831 /* 832 * For these operations we need the types before promotion 833 * and balancing. 834 */ 835 for (tn=ln; tn->tn_op==CVT && !tn->tn_cast; tn=tn->tn_left) 836 continue; 837 olt = tn->tn_type->t_tspec; 838 for (tn=rn; tn->tn_op==CVT && !tn->tn_cast; tn=tn->tn_left) 839 continue; 840 ort = tn->tn_type->t_tspec; 841 } 842 843 switch (op) { 844 case POINT: 845 /* 846 * Most errors required by ANSI C are reported in strmemb(). 847 * Here we only must check for totaly wrong things. 848 */ 849 if (lt == FUNC || lt == VOID || ltp->t_isfield || 850 ((lt != STRUCT && lt != UNION) && !ln->tn_lvalue)) { 851 /* Without tflag we got already an error */ 852 if (tflag) 853 /* unacceptable operand of %s */ 854 error(111, mp->m_name); 855 return (0); 856 } 857 /* Now we have an object we can create a pointer to */ 858 break; 859 case ARROW: 860 if (lt != PTR && !(tflag && isityp(lt))) { 861 /* Without tflag we got already an error */ 862 if (tflag) 863 /* unacceptabel operand of %s */ 864 error(111, mp->m_name); 865 return (0); 866 } 867 break; 868 case INCAFT: 869 case DECAFT: 870 case INCBEF: 871 case DECBEF: 872 /* operands have scalar types (checked above) */ 873 if (!ln->tn_lvalue) { 874 if (ln->tn_op == CVT && ln->tn_cast && 875 ln->tn_left->tn_op == LOAD) { 876 /* a cast to non-ptr does not yield an lvalue */ 877 if (ln->tn_type->t_tspec == PTR) 878 break; 879 error(163); 880 } 881 /* %soperand of %s must be lvalue */ 882 error(114, "", mp->m_name); 883 return (0); 884 } else if (ltp->t_const) { 885 /* %soperand of %s must be modifiable lvalue */ 886 if (!tflag) 887 warning(115, "", mp->m_name); 888 } 889 break; 890 case AMPER: 891 if (lt == ARRAY || lt == FUNC) { 892 /* ok, a warning comes later (in bldamper()) */ 893 } else if (!ln->tn_lvalue) { 894 if (ln->tn_op == CVT && ln->tn_cast && 895 ln->tn_left->tn_op == LOAD) { 896 /* a cast to non-ptr does not yield an lvalue */ 897 if (ln->tn_type->t_tspec == PTR) 898 break; 899 error(163); 900 } 901 /* %soperand of %s must be lvalue */ 902 error(114, "", mp->m_name); 903 return (0); 904 } else if (issclt(lt)) { 905 if (ltp->t_isfield) { 906 /* cannot take address of bit-field */ 907 error(112); 908 return (0); 909 } 910 } else if (lt != STRUCT && lt != UNION) { 911 /* unacceptable operand of %s */ 912 error(111, mp->m_name); 913 return (0); 914 } 915 if (ln->tn_op == NAME && ln->tn_sym->s_reg) { 916 /* cannot take address of register %s */ 917 error(113, ln->tn_sym->s_name); 918 return (0); 919 } 920 break; 921 case STAR: 922 /* until now there were no type checks for this operator */ 923 if (lt != PTR) { 924 /* cannot dereference non-pointer type */ 925 error(96); 926 return (0); 927 } 928 break; 929 case PLUS: 930 /* operands have scalar types (checked above) */ 931 if ((lt == PTR && !isityp(rt)) || (rt == PTR && !isityp(lt))) { 932 incompat(op, lt, rt); 933 return (0); 934 } 935 break; 936 case MINUS: 937 /* operands have scalar types (checked above) */ 938 if (lt == PTR && (!isityp(rt) && rt != PTR)) { 939 incompat(op, lt, rt); 940 return (0); 941 } else if (rt == PTR && lt != PTR) { 942 incompat(op, lt, rt); 943 return (0); 944 } 945 if (lt == PTR && rt == PTR) { 946 if (!eqtype(lstp, rstp, 1, 0, NULL)) { 947 /* illegal pointer subtraction */ 948 error(116); 949 } 950 } 951 break; 952 case SHR: 953 /* operands have integer types (checked above) */ 954 if (pflag && !isutyp(lt)) { 955 /* 956 * The left operand is signed. This means that 957 * the operation is (possibly) nonportable. 958 */ 959 /* bitwise operation on signed value nonportable */ 960 if (ln->tn_op != CON) { 961 /* possibly nonportable */ 962 warning(117); 963 } else if (ln->tn_val->v_quad < 0) { 964 warning(120); 965 } 966 } else if (!tflag && !sflag && !isutyp(olt) && isutyp(ort)) { 967 /* 968 * The left operand would become unsigned in 969 * traditional C. 970 */ 971 if (hflag && 972 (ln->tn_op != CON || ln->tn_val->v_quad < 0)) { 973 /* semantics of %s change in ANSI C; use ... */ 974 warning(118, mp->m_name); 975 } 976 } else if (!tflag && !sflag && !isutyp(olt) && !isutyp(ort) && 977 psize(lt) < psize(rt)) { 978 /* 979 * In traditional C the left operand would be extended, 980 * possibly with 1, and then shifted. 981 */ 982 if (hflag && 983 (ln->tn_op != CON || ln->tn_val->v_quad < 0)) { 984 /* semantics of %s change in ANSI C; use ... */ 985 warning(118, mp->m_name); 986 } 987 } 988 goto shift; 989 case SHL: 990 /* 991 * ANSI C does not perform balancing for shift operations, 992 * but traditional C does. If the width of the right operand 993 * is greather than the width of the left operand, than in 994 * traditional C the left operand would be extendet to the 995 * width of the right operand. For SHL this may result in 996 * different results. 997 */ 998 if (psize(lt) < psize(rt)) { 999 /* 1000 * XXX If both operands are constant make sure 1001 * that there is really a differencs between 1002 * ANSI C and traditional C. 1003 */ 1004 if (hflag) 1005 /* semantics of %s change in ANSI C; use ... */ 1006 warning(118, mp->m_name); 1007 } 1008 shift: 1009 if (rn->tn_op == CON) { 1010 if (!isutyp(rt) && rn->tn_val->v_quad < 0) { 1011 /* negative shift */ 1012 warning(121); 1013 } else if ((uint64_t)rn->tn_val->v_quad == (uint64_t)size(lt)) { 1014 /* shift equal to size fo object */ 1015 warning(267); 1016 } else if ((uint64_t)rn->tn_val->v_quad > (uint64_t)size(lt)) { 1017 /* shift greater than size of object */ 1018 warning(122); 1019 } 1020 } 1021 break; 1022 case EQ: 1023 case NE: 1024 /* 1025 * Accept some things which are allowed with EQ and NE, 1026 * but not with ordered comparisons. 1027 */ 1028 if (lt == PTR && ((rt == PTR && rst == VOID) || isityp(rt))) { 1029 if (rn->tn_op == CON && rn->tn_val->v_quad == 0) 1030 break; 1031 } 1032 if (rt == PTR && ((lt == PTR && lst == VOID) || isityp(lt))) { 1033 if (ln->tn_op == CON && ln->tn_val->v_quad == 0) 1034 break; 1035 } 1036 /* FALLTHROUGH */ 1037 case LT: 1038 case GT: 1039 case LE: 1040 case GE: 1041 if ((lt == PTR || rt == PTR) && lt != rt) { 1042 if (isityp(lt) || isityp(rt)) { 1043 /* illegal comb. of pointer and int., op %s */ 1044 warning(123, mp->m_name); 1045 } else { 1046 incompat(op, lt, rt); 1047 return (0); 1048 } 1049 } else if (lt == PTR && rt == PTR) { 1050 ptrcmpok(op, ln, rn); 1051 } 1052 break; 1053 case QUEST: 1054 if (!issclt(lt)) { 1055 /* first operand must have scalar type, op ? : */ 1056 error(170); 1057 return (0); 1058 } 1059 while (rn->tn_op == CVT) 1060 rn = rn->tn_left; 1061 if (rn->tn_op != COLON) 1062 LERROR("typeok()"); 1063 break; 1064 case COLON: 1065 1066 if (isatyp(lt) && isatyp(rt)) 1067 break; 1068 1069 if (lt == STRUCT && rt == STRUCT && ltp->t_str == rtp->t_str) 1070 break; 1071 if (lt == UNION && rt == UNION && ltp->t_str == rtp->t_str) 1072 break; 1073 1074 /* combination of any pointer and 0, 0L or (void *)0 is ok */ 1075 if (lt == PTR && ((rt == PTR && rst == VOID) || isityp(rt))) { 1076 if (rn->tn_op == CON && rn->tn_val->v_quad == 0) 1077 break; 1078 } 1079 if (rt == PTR && ((lt == PTR && lst == VOID) || isityp(lt))) { 1080 if (ln->tn_op == CON && ln->tn_val->v_quad == 0) 1081 break; 1082 } 1083 1084 if ((lt == PTR && isityp(rt)) || (isityp(lt) && rt == PTR)) { 1085 /* illegal comb. of ptr. and int., op %s */ 1086 warning(123, mp->m_name); 1087 break; 1088 } 1089 1090 if (lt == VOID || rt == VOID) { 1091 if (lt != VOID || rt != VOID) 1092 /* incompatible types in conditional */ 1093 warning(126); 1094 break; 1095 } 1096 1097 if (lt == PTR && rt == PTR && ((lst == VOID && rst == FUNC) || 1098 (lst == FUNC && rst == VOID))) { 1099 /* (void *)0 handled above */ 1100 if (sflag) 1101 /* ANSI C forbids conv. of %s to %s, op %s */ 1102 warning(305, "function pointer", "'void *'", 1103 mp->m_name); 1104 break; 1105 } 1106 1107 if (rt == PTR && lt == PTR) { 1108 if (eqptrtype(lstp, rstp, 1)) 1109 break; 1110 if (!eqtype(lstp, rstp, 1, 0, NULL)) 1111 illptrc(mp, ltp, rtp); 1112 break; 1113 } 1114 1115 /* incompatible types in conditional */ 1116 error(126); 1117 return (0); 1118 1119 case ASSIGN: 1120 case INIT: 1121 case FARG: 1122 case RETURN: 1123 if (!asgntypok(op, arg, ln, rn)) 1124 return (0); 1125 goto assign; 1126 case MULASS: 1127 case DIVASS: 1128 case MODASS: 1129 goto assign; 1130 case ADDASS: 1131 case SUBASS: 1132 /* operands have scalar types (checked above) */ 1133 if ((lt == PTR && !isityp(rt)) || rt == PTR) { 1134 incompat(op, lt, rt); 1135 return (0); 1136 } 1137 goto assign; 1138 case SHLASS: 1139 goto assign; 1140 case SHRASS: 1141 if (pflag && !isutyp(lt) && !(tflag && isutyp(rt))) { 1142 /* bitwise operation on s.v. possibly nonportabel */ 1143 warning(117); 1144 } 1145 goto assign; 1146 case ANDASS: 1147 case XORASS: 1148 case ORASS: 1149 goto assign; 1150 assign: 1151 if (!ln->tn_lvalue) { 1152 if (ln->tn_op == CVT && ln->tn_cast && 1153 ln->tn_left->tn_op == LOAD) { 1154 /* a cast to non-ptr does not yield an lvalue */ 1155 if (ln->tn_type->t_tspec == PTR) 1156 break; 1157 error(163); 1158 } 1159 /* %soperand of %s must be lvalue */ 1160 error(114, "left ", mp->m_name); 1161 return (0); 1162 } else if (ltp->t_const || ((lt == STRUCT || lt == UNION) && 1163 conmemb(ltp))) { 1164 /* %soperand of %s must be modifiable lvalue */ 1165 if (!tflag) 1166 warning(115, "left ", mp->m_name); 1167 } 1168 break; 1169 case COMMA: 1170 if (!modtab[ln->tn_op].m_sideeff) 1171 nulleff(ln); 1172 break; 1173 /* LINTED (enumeration values not handled in switch) */ 1174 case CON: 1175 case CASE: 1176 case PUSH: 1177 case LOAD: 1178 case ICALL: 1179 case CVT: 1180 case CALL: 1181 case FSEL: 1182 case STRING: 1183 case NAME: 1184 case LOGOR: 1185 case LOGAND: 1186 case OR: 1187 case XOR: 1188 case AND: 1189 case MOD: 1190 case DIV: 1191 case MULT: 1192 case UMINUS: 1193 case UPLUS: 1194 case DEC: 1195 case INC: 1196 case COMPL: 1197 case NOT: 1198 case NOOP: 1199 case REAL: 1200 case IMAG: 1201 break; 1202 } 1203 1204 if (mp->m_badeop && 1205 (ltp->t_isenum || (mp->m_binary && rtp->t_isenum))) { 1206 chkbeop(op, ln, rn); 1207 } else if (mp->m_enumop && (ltp->t_isenum && rtp && rtp->t_isenum)) { 1208 chkeop2(op, arg, ln, rn); 1209 } else if (mp->m_enumop && (ltp->t_isenum || (rtp && rtp->t_isenum))) { 1210 chkeop1(op, arg, ln, rn); 1211 } 1212 1213 return (1); 1214 } 1215 1216 static void 1217 ptrcmpok(op_t op, tnode_t *ln, tnode_t *rn) 1218 { 1219 type_t *ltp, *rtp; 1220 tspec_t lt, rt; 1221 const char *lts, *rts; 1222 1223 lt = (ltp = ln->tn_type)->t_subt->t_tspec; 1224 rt = (rtp = rn->tn_type)->t_subt->t_tspec; 1225 1226 if (lt == VOID || rt == VOID) { 1227 if (sflag && (lt == FUNC || rt == FUNC)) { 1228 /* (void *)0 already handled in typeok() */ 1229 *(lt == FUNC ? <s : &rts) = "function pointer"; 1230 *(lt == VOID ? <s : &rts) = "'void *'"; 1231 /* ANSI C forbids comparison of %s with %s */ 1232 warning(274, lts, rts); 1233 } 1234 return; 1235 } 1236 1237 if (!eqtype(ltp->t_subt, rtp->t_subt, 1, 0, NULL)) { 1238 illptrc(&modtab[op], ltp, rtp); 1239 return; 1240 } 1241 1242 if (lt == FUNC && rt == FUNC) { 1243 if (sflag && op != EQ && op != NE) 1244 /* ANSI C forbids ordered comp. of func ptr */ 1245 warning(125); 1246 } 1247 } 1248 1249 /* 1250 * Checks type compatibility for ASSIGN, INIT, FARG and RETURN 1251 * and prints warnings/errors if necessary. 1252 * If the types are (almost) compatible, 1 is returned, otherwise 0. 1253 */ 1254 static int 1255 asgntypok(op_t op, int arg, tnode_t *ln, tnode_t *rn) 1256 { 1257 tspec_t lt, rt, lst = NOTSPEC, rst = NOTSPEC; 1258 type_t *ltp, *rtp, *lstp = NULL, *rstp = NULL; 1259 mod_t *mp; 1260 const char *lts, *rts; 1261 char lbuf[128], rbuf[128]; 1262 1263 if ((lt = (ltp = ln->tn_type)->t_tspec) == PTR) 1264 lst = (lstp = ltp->t_subt)->t_tspec; 1265 if ((rt = (rtp = rn->tn_type)->t_tspec) == PTR) 1266 rst = (rstp = rtp->t_subt)->t_tspec; 1267 mp = &modtab[op]; 1268 1269 if (isatyp(lt) && isatyp(rt)) 1270 return (1); 1271 1272 if ((lt == STRUCT || lt == UNION) && (rt == STRUCT || rt == UNION)) 1273 /* both are struct or union */ 1274 return (ltp->t_str == rtp->t_str); 1275 1276 /* 0, 0L and (void *)0 may be assigned to any pointer */ 1277 if (lt == PTR && ((rt == PTR && rst == VOID) || isityp(rt))) { 1278 if (rn->tn_op == CON && rn->tn_val->v_quad == 0) 1279 return (1); 1280 } 1281 1282 if (lt == PTR && rt == PTR && (lst == VOID || rst == VOID)) { 1283 /* two pointers, at least one pointer to void */ 1284 if (sflag && (lst == FUNC || rst == FUNC)) { 1285 /* comb. of ptr to func and ptr to void */ 1286 *(lst == FUNC ? <s : &rts) = "function pointer"; 1287 *(lst == VOID ? <s : &rts) = "'void *'"; 1288 switch (op) { 1289 case INIT: 1290 case RETURN: 1291 /* ANSI C forbids conversion of %s to %s */ 1292 warning(303, rts, lts); 1293 break; 1294 case FARG: 1295 /* ANSI C forbids conv. of %s to %s, arg #%d */ 1296 warning(304, rts, lts, arg); 1297 break; 1298 default: 1299 /* ANSI C forbids conv. of %s to %s, op %s */ 1300 warning(305, rts, lts, mp->m_name); 1301 break; 1302 } 1303 } 1304 } 1305 1306 if (lt == PTR && rt == PTR && (lst == VOID || rst == VOID || 1307 eqtype(lstp, rstp, 1, 0, NULL))) { 1308 /* compatible pointer types (qualifiers ignored) */ 1309 if (!tflag && 1310 ((!lstp->t_const && rstp->t_const) || 1311 (!lstp->t_volatile && rstp->t_volatile))) { 1312 /* left side has not all qualifiers of right */ 1313 tyname(lbuf, sizeof(lbuf), lstp); 1314 tyname(rbuf, sizeof(rbuf), rstp); 1315 switch (op) { 1316 case INIT: 1317 case RETURN: 1318 /* incompatible pointer types */ 1319 warning(182, lbuf, rbuf); 1320 break; 1321 case FARG: 1322 /* argument has incompat. ptr. type, arg #%d */ 1323 warning(153, arg, lbuf, rbuf); 1324 break; 1325 default: 1326 /* operands have incompat. ptr. types, op %s */ 1327 warning(128, mp->m_name, lbuf, rbuf); 1328 break; 1329 } 1330 } 1331 return (1); 1332 } 1333 1334 if ((lt == PTR && isityp(rt)) || (isityp(lt) && rt == PTR)) { 1335 switch (op) { 1336 case INIT: 1337 case RETURN: 1338 /* illegal combination of pointer and integer */ 1339 warning(183); 1340 break; 1341 case FARG: 1342 /* illegal comb. of ptr. and int., arg #%d */ 1343 warning(154, arg); 1344 break; 1345 default: 1346 /* illegal comb. of ptr. and int., op %s */ 1347 warning(123, mp->m_name); 1348 break; 1349 } 1350 return (1); 1351 } 1352 1353 if (lt == PTR && rt == PTR) { 1354 switch (op) { 1355 case INIT: 1356 case RETURN: 1357 illptrc(NULL, ltp, rtp); 1358 break; 1359 case FARG: 1360 /* argument has incompatible pointer type, arg #%d */ 1361 warning(153, arg, tyname(lbuf, sizeof(lbuf), ltp), 1362 tyname(rbuf, sizeof(rbuf), rtp)); 1363 break; 1364 default: 1365 illptrc(mp, ltp, rtp); 1366 break; 1367 } 1368 return (1); 1369 } 1370 1371 switch (op) { 1372 case INIT: 1373 /* initialisation type mismatch */ 1374 error(185); 1375 break; 1376 case RETURN: 1377 /* return value type mismatch */ 1378 error(211); 1379 break; 1380 case FARG: 1381 /* argument is incompatible with prototype, arg #%d */ 1382 warning(155, arg); 1383 break; 1384 default: 1385 incompat(op, lt, rt); 1386 break; 1387 } 1388 1389 return (0); 1390 } 1391 1392 /* 1393 * Prints a warning if an operator, which should be senseless for an 1394 * enum type, is applied to an enum type. 1395 */ 1396 static void 1397 chkbeop(op_t op, tnode_t *ln, tnode_t *rn) 1398 { 1399 mod_t *mp; 1400 1401 if (!eflag) 1402 return; 1403 1404 mp = &modtab[op]; 1405 1406 if (!(ln->tn_type->t_isenum || 1407 (mp->m_binary && rn->tn_type->t_isenum))) { 1408 return; 1409 } 1410 1411 /* 1412 * Enum as offset to a pointer is an exception (otherwise enums 1413 * could not be used as array indizes). 1414 */ 1415 if (op == PLUS && 1416 ((ln->tn_type->t_isenum && rn->tn_type->t_tspec == PTR) || 1417 (rn->tn_type->t_isenum && ln->tn_type->t_tspec == PTR))) { 1418 return; 1419 } 1420 1421 /* dubious operation on enum, op %s */ 1422 warning(241, mp->m_name); 1423 1424 } 1425 1426 /* 1427 * Prints a warning if an operator is applied to two different enum types. 1428 */ 1429 static void 1430 chkeop2(op_t op, int arg, tnode_t *ln, tnode_t *rn) 1431 { 1432 mod_t *mp; 1433 1434 mp = &modtab[op]; 1435 1436 if (ln->tn_type->t_enum != rn->tn_type->t_enum) { 1437 switch (op) { 1438 case INIT: 1439 /* enum type mismatch in initialisation */ 1440 warning(210); 1441 break; 1442 case FARG: 1443 /* enum type mismatch, arg #%d */ 1444 warning(156, arg); 1445 break; 1446 case RETURN: 1447 /* return value type mismatch */ 1448 warning(211); 1449 break; 1450 default: 1451 /* enum type mismatch, op %s */ 1452 warning(130, mp->m_name); 1453 break; 1454 } 1455 } else if (Pflag && mp->m_comp && op != EQ && op != NE) { 1456 if (eflag) 1457 /* dubious comparisons of enums */ 1458 warning(243, mp->m_name); 1459 } 1460 } 1461 1462 /* 1463 * Prints a warning if an operator has both enum end other integer 1464 * types. 1465 */ 1466 static void 1467 chkeop1(op_t op, int arg, tnode_t *ln, tnode_t *rn) 1468 { 1469 char lbuf[64], rbuf[64]; 1470 1471 if (!eflag) 1472 return; 1473 1474 switch (op) { 1475 case INIT: 1476 /* 1477 * Initializations with 0 should be allowed. Otherwise, 1478 * we should complain about all uninitialized enums, 1479 * consequently. 1480 */ 1481 if (!rn->tn_type->t_isenum && rn->tn_op == CON && 1482 isityp(rn->tn_type->t_tspec) && rn->tn_val->v_quad == 0) { 1483 return; 1484 } 1485 /* initialisation of '%s' with '%s' */ 1486 warning(277, tyname(lbuf, sizeof(lbuf), ln->tn_type), 1487 tyname(rbuf, sizeof(rbuf), rn->tn_type)); 1488 break; 1489 case FARG: 1490 /* combination of '%s' and '%s', arg #%d */ 1491 warning(278, tyname(lbuf, sizeof(lbuf), ln->tn_type), 1492 tyname(rbuf, sizeof(rbuf), rn->tn_type), arg); 1493 break; 1494 case RETURN: 1495 /* combination of '%s' and '%s' in return */ 1496 warning(279, tyname(lbuf, sizeof(lbuf), ln->tn_type), 1497 tyname(rbuf, sizeof(rbuf), rn->tn_type)); 1498 break; 1499 default: 1500 /* combination of '%s' and %s, op %s */ 1501 warning(242, tyname(lbuf, sizeof(lbuf), ln->tn_type), 1502 tyname(rbuf, sizeof(rbuf), rn->tn_type), 1503 modtab[op].m_name); 1504 break; 1505 } 1506 } 1507 1508 /* 1509 * Build and initialize a new node. 1510 */ 1511 static tnode_t * 1512 mktnode(op_t op, type_t *type, tnode_t *ln, tnode_t *rn) 1513 { 1514 tnode_t *ntn; 1515 tspec_t t; 1516 1517 ntn = getnode(); 1518 1519 ntn->tn_op = op; 1520 ntn->tn_type = type; 1521 ntn->tn_left = ln; 1522 ntn->tn_right = rn; 1523 1524 if (op == STAR || op == FSEL) { 1525 if (ln->tn_type->t_tspec == PTR) { 1526 t = ln->tn_type->t_subt->t_tspec; 1527 if (t != FUNC && t != VOID) 1528 ntn->tn_lvalue = 1; 1529 } else { 1530 LERROR("mktnode()"); 1531 } 1532 } 1533 1534 return (ntn); 1535 } 1536 1537 /* 1538 * Performs usual conversion of operands to (unsigned) int. 1539 * 1540 * If tflag is set or the operand is a function argument with no 1541 * type information (no prototype or variable # of args), convert 1542 * float to double. 1543 */ 1544 tnode_t * 1545 promote(op_t op, int farg, tnode_t *tn) 1546 { 1547 tspec_t t; 1548 type_t *ntp; 1549 u_int len; 1550 1551 t = tn->tn_type->t_tspec; 1552 1553 if (!isatyp(t)) 1554 return (tn); 1555 1556 if (!tflag) { 1557 /* 1558 * ANSI C requires that the result is always of type INT 1559 * if INT can represent all possible values of the previous 1560 * type. 1561 */ 1562 if (tn->tn_type->t_isfield) { 1563 len = tn->tn_type->t_flen; 1564 if (size(INT) > len) { 1565 t = INT; 1566 } else { 1567 if (size(INT) != len) 1568 LERROR("promote()"); 1569 if (isutyp(t)) { 1570 t = UINT; 1571 } else { 1572 t = INT; 1573 } 1574 } 1575 } else if (t == CHAR || t == UCHAR || t == SCHAR) { 1576 t = (size(CHAR) < size(INT) || t != UCHAR) ? 1577 INT : UINT; 1578 } else if (t == SHORT || t == USHORT) { 1579 t = (size(SHORT) < size(INT) || t == SHORT) ? 1580 INT : UINT; 1581 } else if (t == ENUM) { 1582 t = INT; 1583 } else if (farg && t == FLOAT) { 1584 t = DOUBLE; 1585 } 1586 } else { 1587 /* 1588 * In traditional C, keep unsigned and promote FLOAT 1589 * to DOUBLE. 1590 */ 1591 if (t == UCHAR || t == USHORT) { 1592 t = UINT; 1593 } else if (t == CHAR || t == SCHAR || t == SHORT) { 1594 t = INT; 1595 } else if (t == FLOAT) { 1596 t = DOUBLE; 1597 } else if (t == ENUM) { 1598 t = INT; 1599 } 1600 } 1601 1602 if (t != tn->tn_type->t_tspec) { 1603 ntp = tduptyp(tn->tn_type); 1604 ntp->t_tspec = t; 1605 /* 1606 * Keep t_isenum so we are later able to check compatibility 1607 * of enum types. 1608 */ 1609 tn = convert(op, 0, ntp, tn); 1610 } 1611 1612 return (tn); 1613 } 1614 1615 /* 1616 * Insert conversions which are necessary to give both operands the same 1617 * type. This is done in different ways for traditional C and ANIS C. 1618 */ 1619 static void 1620 balance(op_t op, tnode_t **lnp, tnode_t **rnp) 1621 { 1622 tspec_t lt, rt, t; 1623 int i, u; 1624 type_t *ntp; 1625 static tspec_t tl[] = { 1626 LDOUBLE, DOUBLE, FLOAT, UQUAD, QUAD, ULONG, LONG, UINT, INT, 1627 }; 1628 1629 lt = (*lnp)->tn_type->t_tspec; 1630 rt = (*rnp)->tn_type->t_tspec; 1631 1632 if (!isatyp(lt) || !isatyp(rt)) 1633 return; 1634 1635 if (!tflag) { 1636 if (lt == rt) { 1637 t = lt; 1638 } else if (lt == LCOMPLEX || rt == LCOMPLEX) { 1639 t = LCOMPLEX; 1640 } else if (lt == DCOMPLEX || rt == DCOMPLEX) { 1641 t = DCOMPLEX; 1642 } else if (lt == COMPLEX || rt == COMPLEX) { 1643 t = COMPLEX; 1644 } else if (lt == FCOMPLEX || rt == FCOMPLEX) { 1645 t = FCOMPLEX; 1646 } else if (lt == LDOUBLE || rt == LDOUBLE) { 1647 t = LDOUBLE; 1648 } else if (lt == DOUBLE || rt == DOUBLE) { 1649 t = DOUBLE; 1650 } else if (lt == FLOAT || rt == FLOAT) { 1651 t = FLOAT; 1652 } else { 1653 /* 1654 * If type A has more bits than type B it should 1655 * be able to hold all possible values of type B. 1656 */ 1657 if (size(lt) > size(rt)) { 1658 t = lt; 1659 } else if (size(lt) < size(rt)) { 1660 t = rt; 1661 } else { 1662 for (i = 3; tl[i] != INT; i++) { 1663 if (tl[i] == lt || tl[i] == rt) 1664 break; 1665 } 1666 if ((isutyp(lt) || isutyp(rt)) && 1667 !isutyp(tl[i])) { 1668 i--; 1669 } 1670 t = tl[i]; 1671 } 1672 } 1673 } else { 1674 /* Keep unsigned in traditional C */ 1675 u = isutyp(lt) || isutyp(rt); 1676 for (i = 0; tl[i] != INT; i++) { 1677 if (lt == tl[i] || rt == tl[i]) 1678 break; 1679 } 1680 t = tl[i]; 1681 if (u && isityp(t) && !isutyp(t)) 1682 t = utyp(t); 1683 } 1684 1685 if (t != lt) { 1686 ntp = tduptyp((*lnp)->tn_type); 1687 ntp->t_tspec = t; 1688 *lnp = convert(op, 0, ntp, *lnp); 1689 } 1690 if (t != rt) { 1691 ntp = tduptyp((*rnp)->tn_type); 1692 ntp->t_tspec = t; 1693 *rnp = convert(op, 0, ntp, *rnp); 1694 } 1695 } 1696 1697 /* 1698 * Insert a conversion operator, which converts the type of the node 1699 * to another given type. 1700 * If op is FARG, arg is the number of the argument (used for warnings). 1701 */ 1702 tnode_t * 1703 convert(op_t op, int arg, type_t *tp, tnode_t *tn) 1704 { 1705 tnode_t *ntn; 1706 tspec_t nt, ot, ost = NOTSPEC; 1707 1708 if (tn->tn_lvalue) 1709 LERROR("convert()"); 1710 1711 nt = tp->t_tspec; 1712 if ((ot = tn->tn_type->t_tspec) == PTR) 1713 ost = tn->tn_type->t_subt->t_tspec; 1714 1715 if (!tflag && !sflag && op == FARG) 1716 ptconv(arg, nt, ot, tp, tn); 1717 if (isityp(nt) && isityp(ot)) { 1718 iiconv(op, arg, nt, ot, tp, tn); 1719 } else if (nt == PTR && ((ot == PTR && ost == VOID) || isityp(ot)) && 1720 tn->tn_op == CON && tn->tn_val->v_quad == 0) { 1721 /* 0, 0L and (void *)0 may be assigned to any pointer. */ 1722 } else if (isityp(nt) && ot == PTR) { 1723 piconv(op, nt, tp, tn); 1724 } else if (nt == PTR && ot == PTR) { 1725 ppconv(op, tn, tp); 1726 } 1727 1728 ntn = getnode(); 1729 ntn->tn_op = CVT; 1730 ntn->tn_type = tp; 1731 ntn->tn_cast = op == CVT; 1732 if (tn->tn_op != CON || nt == VOID) { 1733 ntn->tn_left = tn; 1734 } else { 1735 ntn->tn_op = CON; 1736 ntn->tn_val = tgetblk(sizeof (val_t)); 1737 cvtcon(op, arg, ntn->tn_type, ntn->tn_val, tn->tn_val); 1738 } 1739 1740 return (ntn); 1741 } 1742 1743 /* 1744 * Print a warning if a prototype causes a type conversion that is 1745 * different from what would happen to the same argument in the 1746 * absence of a prototype. 1747 * 1748 * Errors/Warnings about illegal type combinations are already printed 1749 * in asgntypok(). 1750 */ 1751 static void 1752 ptconv(int arg, tspec_t nt, tspec_t ot, type_t *tp, tnode_t *tn) 1753 { 1754 tnode_t *ptn; 1755 char buf[64]; 1756 1757 if (!isatyp(nt) || !isatyp(ot)) 1758 return; 1759 1760 /* 1761 * If the type of the formal parameter is char/short, a warning 1762 * would be useless, because functions declared the old style 1763 * can't expect char/short arguments. 1764 */ 1765 if (nt == CHAR || nt == UCHAR || nt == SHORT || nt == USHORT) 1766 return; 1767 1768 /* get default promotion */ 1769 ptn = promote(NOOP, 1, tn); 1770 ot = ptn->tn_type->t_tspec; 1771 1772 /* return if types are the same with and without prototype */ 1773 if (nt == ot || (nt == ENUM && ot == INT)) 1774 return; 1775 1776 if (isftyp(nt) != isftyp(ot) || psize(nt) != psize(ot)) { 1777 /* representation and/or width change */ 1778 if (!isityp(ot) || psize(ot) > psize(INT)) { 1779 /* conversion to '%s' due to prototype, arg #%d */ 1780 warning(259, tyname(buf, sizeof(buf), tp), arg); 1781 } 1782 } else if (hflag) { 1783 /* 1784 * they differ in sign or base type (char, short, int, 1785 * long, long long, float, double, long double) 1786 * 1787 * if they differ only in sign and the argument is a constant 1788 * and the msb of the argument is not set, print no warning 1789 */ 1790 if (ptn->tn_op == CON && isityp(nt) && styp(nt) == styp(ot) && 1791 msb(ptn->tn_val->v_quad, ot, -1) == 0) { 1792 /* ok */ 1793 } else { 1794 /* conversion to '%s' due to prototype, arg #%d */ 1795 warning(259, tyname(buf, sizeof(buf), tp), arg); 1796 } 1797 } 1798 } 1799 1800 /* 1801 * Print warnings for conversions of integer types which my cause 1802 * problems. 1803 */ 1804 /* ARGSUSED */ 1805 static void 1806 iiconv(op_t op, int arg, tspec_t nt, tspec_t ot, type_t *tp, tnode_t *tn) 1807 { 1808 char lbuf[64], rbuf[64], opbuf[16]; 1809 if (tn->tn_op == CON) 1810 return; 1811 1812 if (op == CVT) 1813 return; 1814 1815 if (Pflag && psize(nt) > psize(ot) && isutyp(nt) != isutyp(ot)) { 1816 /* conversion to %s may sign-extend incorrectly (, arg #%d) */ 1817 if (aflag && pflag) { 1818 if (op == FARG) { 1819 warning(297, tyname(lbuf, sizeof(lbuf), tp), 1820 arg); 1821 } else { 1822 warning(131, tyname(lbuf, sizeof(lbuf), tp)); 1823 } 1824 } 1825 } 1826 1827 if (Pflag && psize(nt) > psize(ot)) { 1828 switch (tn->tn_op) { 1829 case PLUS: 1830 case MINUS: 1831 case MULT: 1832 case SHL: 1833 warning(324, 1834 tyname(rbuf, sizeof(rbuf), gettyp(ot)), 1835 tyname(lbuf, sizeof(lbuf), tp), 1836 prtnode(opbuf, sizeof(opbuf), tn)); 1837 break; 1838 default: 1839 break; 1840 } 1841 } 1842 1843 if (psize(nt) < psize(ot) && 1844 (ot == LONG || ot == ULONG || ot == QUAD || ot == UQUAD || 1845 aflag > 1)) { 1846 /* conversion from '%s' may lose accuracy */ 1847 if (aflag) { 1848 if (op == FARG) { 1849 warning(298, 1850 tyname(rbuf, sizeof(rbuf), tn->tn_type), 1851 tyname(lbuf, sizeof(lbuf), tp), 1852 arg); 1853 } else { 1854 warning(132, 1855 tyname(rbuf, sizeof(rbuf), tn->tn_type), 1856 tyname(lbuf, sizeof(lbuf), tp)); 1857 } 1858 } 1859 } 1860 } 1861 1862 /* 1863 * Print warnings for dubious conversions of pointer to integer. 1864 */ 1865 static void 1866 piconv(op_t op, tspec_t nt, type_t *tp, tnode_t *tn) 1867 { 1868 char buf[64]; 1869 1870 if (tn->tn_op == CON) 1871 return; 1872 1873 if (op != CVT) { 1874 /* We got already an error. */ 1875 return; 1876 } 1877 1878 if (psize(nt) < psize(PTR)) { 1879 if (pflag && size(nt) >= size(PTR)) { 1880 /* conv. of pointer to %s may lose bits */ 1881 warning(134, tyname(buf, sizeof(buf), tp)); 1882 } else { 1883 /* conv. of pointer to %s loses bits */ 1884 warning(133, tyname(buf, sizeof(buf), tp)); 1885 } 1886 } 1887 } 1888 1889 /* 1890 * Print warnings for questionable pointer conversions. 1891 */ 1892 static void 1893 ppconv(op_t op, tnode_t *tn, type_t *tp) 1894 { 1895 tspec_t nt, ot; 1896 const char *nts, *ots; 1897 1898 /* 1899 * We got already an error (pointers of different types 1900 * without a cast) or we will not get a warning. 1901 */ 1902 if (op != CVT) 1903 return; 1904 1905 nt = tp->t_subt->t_tspec; 1906 ot = tn->tn_type->t_subt->t_tspec; 1907 1908 if (nt == VOID || ot == VOID) { 1909 if (sflag && (nt == FUNC || ot == FUNC)) { 1910 /* (void *)0 already handled in convert() */ 1911 *(nt == FUNC ? &nts : &ots) = "function pointer"; 1912 *(nt == VOID ? &nts : &ots) = "'void *'"; 1913 /* ANSI C forbids conversion of %s to %s */ 1914 warning(303, ots, nts); 1915 } 1916 return; 1917 } else if (nt == FUNC && ot == FUNC) { 1918 return; 1919 } else if (nt == FUNC || ot == FUNC) { 1920 /* questionable conversion of function pointer */ 1921 warning(229); 1922 return; 1923 } 1924 1925 if (getbound(tp->t_subt) > getbound(tn->tn_type->t_subt)) { 1926 if (hflag) 1927 /* possible pointer alignment problem */ 1928 warning(135); 1929 } 1930 if (((nt == STRUCT || nt == UNION) && 1931 tp->t_subt->t_str != tn->tn_type->t_subt->t_str) || 1932 psize(nt) != psize(ot)) { 1933 if (cflag) { 1934 /* pointer casts may be troublesome */ 1935 warning(247); 1936 } 1937 } 1938 } 1939 1940 /* 1941 * Converts a typed constant in a constant of another type. 1942 * 1943 * op operator which requires conversion 1944 * arg if op is FARG, # of argument 1945 * tp type in which to convert the constant 1946 * nv new constant 1947 * v old constant 1948 */ 1949 void 1950 cvtcon(op_t op, int arg, type_t *tp, val_t *nv, val_t *v) 1951 { 1952 char lbuf[64], rbuf[64]; 1953 tspec_t ot, nt; 1954 ldbl_t max = 0.0, min = 0.0; 1955 int sz, rchk; 1956 int64_t xmask, xmsk1; 1957 int osz, nsz; 1958 1959 ot = v->v_tspec; 1960 nt = nv->v_tspec = tp->t_tspec; 1961 rchk = 0; 1962 1963 if (ot == FLOAT || ot == DOUBLE || ot == LDOUBLE) { 1964 switch (nt) { 1965 case BOOL: 1966 max = 1; min = 0; break; 1967 case CHAR: 1968 max = CHAR_MAX; min = CHAR_MIN; break; 1969 case UCHAR: 1970 max = UCHAR_MAX; min = 0; break; 1971 case SCHAR: 1972 max = SCHAR_MAX; min = SCHAR_MIN; break; 1973 case SHORT: 1974 max = SHRT_MAX; min = SHRT_MIN; break; 1975 case USHORT: 1976 max = USHRT_MAX; min = 0; break; 1977 case ENUM: 1978 case INT: 1979 max = INT_MAX; min = INT_MIN; break; 1980 case UINT: 1981 max = (u_int)UINT_MAX; min = 0; break; 1982 case LONG: 1983 max = LONG_MAX; min = LONG_MIN; break; 1984 case ULONG: 1985 max = (u_long)ULONG_MAX; min = 0; break; 1986 case QUAD: 1987 max = QUAD_MAX; min = QUAD_MIN; break; 1988 case UQUAD: 1989 max = (uint64_t)UQUAD_MAX; min = 0; break; 1990 case FLOAT: 1991 case FCOMPLEX: 1992 max = FLT_MAX; min = -FLT_MAX; break; 1993 case DOUBLE: 1994 case DCOMPLEX: 1995 max = DBL_MAX; min = -DBL_MAX; break; 1996 case PTR: 1997 /* Got already an error because of float --> ptr */ 1998 case LDOUBLE: 1999 case LCOMPLEX: 2000 max = LDBL_MAX; min = -LDBL_MAX; break; 2001 default: 2002 LERROR("cvtcon()"); 2003 } 2004 if (v->v_ldbl > max || v->v_ldbl < min) { 2005 if (nt == LDOUBLE) 2006 LERROR("cvtcon()"); 2007 if (op == FARG) { 2008 /* conv. of %s to %s is out of rng., arg #%d */ 2009 warning(295, tyname(lbuf, sizeof(lbuf), 2010 gettyp(ot)), tyname(rbuf, sizeof(rbuf), tp), 2011 arg); 2012 } else { 2013 /* conversion of %s to %s is out of range */ 2014 warning(119, tyname(lbuf, sizeof(lbuf), 2015 gettyp(ot)), 2016 tyname(rbuf, sizeof(rbuf), tp)); 2017 } 2018 v->v_ldbl = v->v_ldbl > 0 ? max : min; 2019 } 2020 if (nt == FLOAT) { 2021 nv->v_ldbl = (float)v->v_ldbl; 2022 } else if (nt == DOUBLE) { 2023 nv->v_ldbl = (double)v->v_ldbl; 2024 } else if (nt == LDOUBLE) { 2025 nv->v_ldbl = v->v_ldbl; 2026 } else { 2027 nv->v_quad = (nt == PTR || isutyp(nt)) ? 2028 (int64_t)v->v_ldbl : (int64_t)v->v_ldbl; 2029 } 2030 } else { 2031 if (nt == FLOAT) { 2032 nv->v_ldbl = (ot == PTR || isutyp(ot)) ? 2033 (float)(uint64_t)v->v_quad : (float)v->v_quad; 2034 } else if (nt == DOUBLE) { 2035 nv->v_ldbl = (ot == PTR || isutyp(ot)) ? 2036 (double)(uint64_t)v->v_quad : (double)v->v_quad; 2037 } else if (nt == LDOUBLE) { 2038 nv->v_ldbl = (ot == PTR || isutyp(ot)) ? 2039 (ldbl_t)(uint64_t)v->v_quad : (ldbl_t)v->v_quad; 2040 } else { 2041 rchk = 1; /* Check for lost precision. */ 2042 nv->v_quad = v->v_quad; 2043 } 2044 } 2045 2046 if (v->v_ansiu && isftyp(nt)) { 2047 /* ANSI C treats constant as unsigned */ 2048 warning(157); 2049 v->v_ansiu = 0; 2050 } else if (v->v_ansiu && (isityp(nt) && !isutyp(nt) && 2051 psize(nt) > psize(ot))) { 2052 /* ANSI C treats constant as unsigned */ 2053 warning(157); 2054 v->v_ansiu = 0; 2055 } 2056 2057 if (nt != FLOAT && nt != DOUBLE && nt != LDOUBLE) { 2058 sz = tp->t_isfield ? tp->t_flen : size(nt); 2059 nv->v_quad = xsign(nv->v_quad, nt, sz); 2060 } 2061 2062 if (rchk && op != CVT) { 2063 osz = size(ot); 2064 nsz = tp->t_isfield ? tp->t_flen : size(nt); 2065 xmask = qlmasks[nsz] ^ qlmasks[osz]; 2066 xmsk1 = qlmasks[nsz] ^ qlmasks[osz - 1]; 2067 /* 2068 * For bitwise operations we are not interested in the 2069 * value, but in the bits itself. 2070 */ 2071 if (op == ORASS || op == OR || op == XOR) { 2072 /* 2073 * Print a warning if bits which were set are 2074 * lost due to the conversion. 2075 * This can happen with operator ORASS only. 2076 */ 2077 if (nsz < osz && (v->v_quad & xmask) != 0) { 2078 /* constant truncated by conv., op %s */ 2079 warning(306, modtab[op].m_name); 2080 } 2081 } else if (op == ANDASS || op == AND) { 2082 /* 2083 * Print a warning if additional bits are not all 1 2084 * and the most significant bit of the old value is 1, 2085 * or if at least one (but not all) removed bit was 0. 2086 */ 2087 if (nsz > osz && 2088 (nv->v_quad & qbmasks[osz - 1]) != 0 && 2089 (nv->v_quad & xmask) != xmask) { 2090 /* 2091 * extra bits set to 0 in conversion 2092 * of '%s' to '%s', op %s 2093 */ 2094 warning(309, tyname(lbuf, sizeof(lbuf), 2095 gettyp(ot)), tyname(rbuf, sizeof(rbuf), tp), 2096 modtab[op].m_name); 2097 } else if (nsz < osz && 2098 (v->v_quad & xmask) != xmask && 2099 (v->v_quad & xmask) != 0) { 2100 /* const. truncated by conv., op %s */ 2101 warning(306, modtab[op].m_name); 2102 } 2103 } else if ((nt != PTR && isutyp(nt)) && 2104 (ot != PTR && !isutyp(ot)) && v->v_quad < 0) { 2105 if (op == ASSIGN) { 2106 /* assignment of negative constant to ... */ 2107 warning(164); 2108 } else if (op == INIT) { 2109 /* initialisation of unsigned with neg. ... */ 2110 warning(221); 2111 } else if (op == FARG) { 2112 /* conversion of neg. const. to ..., arg #%d */ 2113 warning(296, arg); 2114 } else if (modtab[op].m_comp) { 2115 /* we get this warning already in chkcomp() */ 2116 } else { 2117 /* conversion of negative constant to ... */ 2118 warning(222); 2119 } 2120 } else if (nv->v_quad != v->v_quad && nsz <= osz && 2121 (v->v_quad & xmask) != 0 && 2122 (isutyp(ot) || (v->v_quad & xmsk1) != xmsk1)) { 2123 /* 2124 * Loss of significant bit(s). All truncated bits 2125 * of unsigned types or all truncated bits plus the 2126 * msb of the target for signed types are considered 2127 * to be significant bits. Loss of significant bits 2128 * means that at least on of the bits was set in an 2129 * unsigned type or that at least one, but not all of 2130 * the bits was set in an signed type. 2131 * Loss of significant bits means that it is not 2132 * possible, also not with necessary casts, to convert 2133 * back to the original type. A example for a 2134 * necessary cast is: 2135 * char c; int i; c = 128; 2136 * i = c; ** yields -128 ** 2137 * i = (unsigned char)c; ** yields 128 ** 2138 */ 2139 if (op == ASSIGN && tp->t_isfield) { 2140 /* precision lost in bit-field assignment */ 2141 warning(166); 2142 } else if (op == ASSIGN) { 2143 /* constant truncated by assignment */ 2144 warning(165); 2145 } else if (op == INIT && tp->t_isfield) { 2146 /* bit-field initializer does not fit */ 2147 warning(180); 2148 } else if (op == INIT) { 2149 /* initializer does not fit */ 2150 warning(178); 2151 } else if (op == CASE) { 2152 /* case label affected by conversion */ 2153 warning(196); 2154 } else if (op == FARG) { 2155 /* conv. of %s to %s is out of rng., arg #%d */ 2156 warning(295, tyname(lbuf, sizeof(lbuf), 2157 gettyp(ot)), tyname(rbuf, sizeof(rbuf), tp), 2158 arg); 2159 } else { 2160 /* conversion of %s to %s is out of range */ 2161 warning(119, tyname(lbuf, sizeof(lbuf), 2162 gettyp(ot)), 2163 tyname(rbuf, sizeof(rbuf), tp)); 2164 } 2165 } else if (nv->v_quad != v->v_quad) { 2166 if (op == ASSIGN && tp->t_isfield) { 2167 /* precision lost in bit-field assignment */ 2168 warning(166); 2169 } else if (op == INIT && tp->t_isfield) { 2170 /* bit-field initializer out of range */ 2171 warning(11); 2172 } else if (op == CASE) { 2173 /* case label affected by conversion */ 2174 warning(196); 2175 } else if (op == FARG) { 2176 /* conv. of %s to %s is out of rng., arg #%d */ 2177 warning(295, tyname(lbuf, sizeof(lbuf), 2178 gettyp(ot)), tyname(rbuf, sizeof(rbuf), tp), 2179 arg); 2180 } else { 2181 /* conversion of %s to %s is out of range */ 2182 warning(119, tyname(lbuf, sizeof(lbuf), 2183 gettyp(ot)), 2184 tyname(rbuf, sizeof(rbuf), tp)); 2185 } 2186 } 2187 } 2188 } 2189 2190 /* 2191 * Called if incompatible types were detected. 2192 * Prints a appropriate warning. 2193 */ 2194 static void 2195 incompat(op_t op, tspec_t lt, tspec_t rt) 2196 { 2197 mod_t *mp; 2198 int e = 0; 2199 2200 mp = &modtab[op]; 2201 2202 if (lt == VOID || (mp->m_binary && rt == VOID)) { 2203 /* void type illegal in expression */ 2204 e = 109; 2205 } else if (op == ASSIGN) { 2206 if ((lt == STRUCT || lt == UNION) && 2207 (rt == STRUCT || rt == UNION)) { 2208 /* assignment of different structures */ 2209 e = 240; 2210 } else { 2211 /* assignment type mismatch */ 2212 e = 171; 2213 } 2214 } else if (mp->m_binary) { 2215 /* operands of %s have incompatible types */ 2216 e = 107; 2217 } else { 2218 /* operand of %s has incompatible type */ 2219 e = 108; 2220 } 2221 switch (e) { 2222 case 0: 2223 return; 2224 case 109: 2225 error(e); 2226 return; 2227 case 108: 2228 case 107: 2229 error(e, mp->m_name, basictyname(lt), basictyname(rt)); 2230 return; 2231 default: 2232 error(e, basictyname(lt), basictyname(rt)); 2233 return; 2234 } 2235 } 2236 2237 /* 2238 * Called if incompatible pointer types are detected. 2239 * Print an appropriate warning. 2240 */ 2241 static void 2242 illptrc(mod_t *mp, type_t *ltp, type_t *rtp) 2243 { 2244 tspec_t lt, rt; 2245 2246 if (ltp->t_tspec != PTR || rtp->t_tspec != PTR) 2247 LERROR("illptrc()"); 2248 2249 lt = ltp->t_subt->t_tspec; 2250 rt = rtp->t_subt->t_tspec; 2251 2252 if ((lt == STRUCT || lt == UNION) && (rt == STRUCT || rt == UNION)) { 2253 if (mp == NULL) { 2254 /* illegal structure pointer combination */ 2255 warning(244); 2256 } else { 2257 /* illegal structure pointer combination, op %s */ 2258 warning(245, mp->m_name); 2259 } 2260 } else { 2261 if (mp == NULL) { 2262 /* illegal pointer combination */ 2263 warning(184); 2264 } else { 2265 /* illegal pointer combination, op %s */ 2266 warning(124, mp->m_name); 2267 } 2268 } 2269 } 2270 2271 /* 2272 * Make sure type (*tpp)->t_subt has at least the qualifiers 2273 * of tp1->t_subt and tp2->t_subt. 2274 */ 2275 static void 2276 mrgqual(type_t **tpp, type_t *tp1, type_t *tp2) 2277 { 2278 2279 if ((*tpp)->t_tspec != PTR || 2280 tp1->t_tspec != PTR || tp2->t_tspec != PTR) { 2281 LERROR("mrgqual()"); 2282 } 2283 2284 if ((*tpp)->t_subt->t_const == 2285 (tp1->t_subt->t_const | tp2->t_subt->t_const) && 2286 (*tpp)->t_subt->t_volatile == 2287 (tp1->t_subt->t_volatile | tp2->t_subt->t_volatile)) { 2288 return; 2289 } 2290 2291 *tpp = tduptyp(*tpp); 2292 (*tpp)->t_subt = tduptyp((*tpp)->t_subt); 2293 (*tpp)->t_subt->t_const = 2294 tp1->t_subt->t_const | tp2->t_subt->t_const; 2295 (*tpp)->t_subt->t_volatile = 2296 tp1->t_subt->t_volatile | tp2->t_subt->t_volatile; 2297 } 2298 2299 /* 2300 * Returns 1 if the given structure or union has a constant member 2301 * (maybe recursively). 2302 */ 2303 static int 2304 conmemb(type_t *tp) 2305 { 2306 sym_t *m; 2307 tspec_t t; 2308 2309 if ((t = tp->t_tspec) != STRUCT && t != UNION) 2310 LERROR("conmemb()"); 2311 for (m = tp->t_str->memb; m != NULL; m = m->s_nxt) { 2312 tp = m->s_type; 2313 if (tp->t_const) 2314 return (1); 2315 if ((t = tp->t_tspec) == STRUCT || t == UNION) { 2316 if (conmemb(m->s_type)) 2317 return (1); 2318 } 2319 } 2320 return (0); 2321 } 2322 2323 /* 2324 * Create a new node for one of the operators POINT and ARROW. 2325 */ 2326 static tnode_t * 2327 bldstr(op_t op, tnode_t *ln, tnode_t *rn) 2328 { 2329 tnode_t *ntn, *ctn; 2330 int nolval; 2331 2332 if (rn->tn_op != NAME) 2333 LERROR("bldstr()"); 2334 if (rn->tn_sym->s_value.v_tspec != INT) 2335 LERROR("bldstr()"); 2336 if (rn->tn_sym->s_scl != MOS && rn->tn_sym->s_scl != MOU) 2337 LERROR("bldstr()"); 2338 2339 /* 2340 * Remember if the left operand is an lvalue (structure members 2341 * are lvalues if and only if the structure itself is an lvalue). 2342 */ 2343 nolval = op == POINT && !ln->tn_lvalue; 2344 2345 if (op == POINT) { 2346 ln = bldamper(ln, 1); 2347 } else if (ln->tn_type->t_tspec != PTR) { 2348 if (!tflag || !isityp(ln->tn_type->t_tspec)) 2349 LERROR("bldstr()"); 2350 ln = convert(NOOP, 0, tincref(gettyp(VOID), PTR), ln); 2351 } 2352 2353 #if PTRDIFF_IS_LONG 2354 ctn = getinode(LONG, rn->tn_sym->s_value.v_quad / CHAR_BIT); 2355 #else 2356 ctn = getinode(INT, rn->tn_sym->s_value.v_quad / CHAR_BIT); 2357 #endif 2358 2359 ntn = mktnode(PLUS, tincref(rn->tn_type, PTR), ln, ctn); 2360 if (ln->tn_op == CON) 2361 ntn = fold(ntn); 2362 2363 if (rn->tn_type->t_isfield) { 2364 ntn = mktnode(FSEL, ntn->tn_type->t_subt, ntn, NULL); 2365 } else { 2366 ntn = mktnode(STAR, ntn->tn_type->t_subt, ntn, NULL); 2367 } 2368 2369 if (nolval) 2370 ntn->tn_lvalue = 0; 2371 2372 return (ntn); 2373 } 2374 2375 /* 2376 * Create a node for INCAFT, INCBEF, DECAFT and DECBEF. 2377 */ 2378 static tnode_t * 2379 bldincdec(op_t op, tnode_t *ln) 2380 { 2381 tnode_t *cn, *ntn; 2382 2383 if (ln == NULL) 2384 LERROR("bldincdec()"); 2385 2386 if (ln->tn_type->t_tspec == PTR) { 2387 cn = plength(ln->tn_type); 2388 } else { 2389 cn = getinode(INT, (int64_t)1); 2390 } 2391 ntn = mktnode(op, ln->tn_type, ln, cn); 2392 2393 return (ntn); 2394 } 2395 2396 /* 2397 * Create a node for REAL, IMAG 2398 */ 2399 static tnode_t * 2400 bldri(op_t op, tnode_t *ln) 2401 { 2402 tnode_t *cn, *ntn; 2403 char buf[64]; 2404 2405 if (ln == NULL) 2406 LERROR("bldincdec()"); 2407 2408 switch (ln->tn_type->t_tspec) { 2409 case LCOMPLEX: 2410 cn = getinode(LDOUBLE, (int64_t)1); 2411 break; 2412 case DCOMPLEX: 2413 cn = getinode(DOUBLE, (int64_t)1); 2414 break; 2415 case FCOMPLEX: 2416 cn = getinode(FLOAT, (int64_t)1); 2417 break; 2418 default: 2419 error(276, op == REAL ? "real" : "imag", 2420 tyname(buf, sizeof(buf), ln->tn_type)); 2421 return NULL; 2422 } 2423 ntn = mktnode(op, cn->tn_type, ln, cn); 2424 2425 return (ntn); 2426 } 2427 /* 2428 * Create a tree node for the & operator 2429 */ 2430 static tnode_t * 2431 bldamper(tnode_t *tn, int noign) 2432 { 2433 tnode_t *ntn; 2434 tspec_t t; 2435 2436 if (!noign && ((t = tn->tn_type->t_tspec) == ARRAY || t == FUNC)) { 2437 /* & before array or function: ignored */ 2438 if (tflag) 2439 warning(127); 2440 return (tn); 2441 } 2442 2443 /* eliminate &* */ 2444 if (tn->tn_op == STAR && 2445 tn->tn_left->tn_type->t_tspec == PTR && 2446 tn->tn_left->tn_type->t_subt == tn->tn_type) { 2447 return (tn->tn_left); 2448 } 2449 2450 ntn = mktnode(AMPER, tincref(tn->tn_type, PTR), tn, NULL); 2451 2452 return (ntn); 2453 } 2454 2455 /* 2456 * Create a node for operators PLUS and MINUS. 2457 */ 2458 static tnode_t * 2459 bldplmi(op_t op, tnode_t *ln, tnode_t *rn) 2460 { 2461 tnode_t *ntn, *ctn; 2462 type_t *tp; 2463 2464 /* If pointer and integer, then pointer to the lhs. */ 2465 if (rn->tn_type->t_tspec == PTR && isityp(ln->tn_type->t_tspec)) { 2466 ntn = ln; 2467 ln = rn; 2468 rn = ntn; 2469 } 2470 2471 if (ln->tn_type->t_tspec == PTR && rn->tn_type->t_tspec != PTR) { 2472 2473 if (!isityp(rn->tn_type->t_tspec)) 2474 LERROR("bldplmi()"); 2475 2476 ctn = plength(ln->tn_type); 2477 if (rn->tn_type->t_tspec != ctn->tn_type->t_tspec) 2478 rn = convert(NOOP, 0, ctn->tn_type, rn); 2479 rn = mktnode(MULT, rn->tn_type, rn, ctn); 2480 if (rn->tn_left->tn_op == CON) 2481 rn = fold(rn); 2482 ntn = mktnode(op, ln->tn_type, ln, rn); 2483 2484 } else if (rn->tn_type->t_tspec == PTR) { 2485 2486 if (ln->tn_type->t_tspec != PTR || op != MINUS) 2487 LERROR("bldplmi()"); 2488 #if PTRDIFF_IS_LONG 2489 tp = gettyp(LONG); 2490 #else 2491 tp = gettyp(INT); 2492 #endif 2493 ntn = mktnode(op, tp, ln, rn); 2494 if (ln->tn_op == CON && rn->tn_op == CON) 2495 ntn = fold(ntn); 2496 ctn = plength(ln->tn_type); 2497 balance(NOOP, &ntn, &ctn); 2498 ntn = mktnode(DIV, tp, ntn, ctn); 2499 2500 } else { 2501 2502 ntn = mktnode(op, ln->tn_type, ln, rn); 2503 2504 } 2505 return (ntn); 2506 } 2507 2508 /* 2509 * Create a node for operators SHL and SHR. 2510 */ 2511 static tnode_t * 2512 bldshft(op_t op, tnode_t *ln, tnode_t *rn) 2513 { 2514 tspec_t t; 2515 tnode_t *ntn; 2516 2517 if ((t = rn->tn_type->t_tspec) != INT && t != UINT) 2518 rn = convert(CVT, 0, gettyp(INT), rn); 2519 ntn = mktnode(op, ln->tn_type, ln, rn); 2520 return (ntn); 2521 } 2522 2523 /* 2524 * Create a node for COLON. 2525 */ 2526 static tnode_t * 2527 bldcol(tnode_t *ln, tnode_t *rn) 2528 { 2529 tspec_t lt, rt, pdt; 2530 type_t *rtp; 2531 tnode_t *ntn; 2532 2533 lt = ln->tn_type->t_tspec; 2534 rt = rn->tn_type->t_tspec; 2535 #if PTRDIFF_IS_LONG 2536 pdt = LONG; 2537 #else 2538 pdt = INT; 2539 #endif 2540 2541 /* 2542 * Arithmetic types are balanced, all other type combinations 2543 * still need to be handled. 2544 */ 2545 if (isatyp(lt) && isatyp(rt)) { 2546 rtp = ln->tn_type; 2547 } else if (lt == VOID || rt == VOID) { 2548 rtp = gettyp(VOID); 2549 } else if (lt == STRUCT || lt == UNION) { 2550 /* Both types must be identical. */ 2551 if (rt != STRUCT && rt != UNION) 2552 LERROR("bldcol()"); 2553 if (ln->tn_type->t_str != rn->tn_type->t_str) 2554 LERROR("bldcol()"); 2555 if (incompl(ln->tn_type)) { 2556 /* unknown operand size, op %s */ 2557 error(138, modtab[COLON].m_name); 2558 return (NULL); 2559 } 2560 rtp = ln->tn_type; 2561 } else if (lt == PTR && isityp(rt)) { 2562 if (rt != pdt) { 2563 rn = convert(NOOP, 0, gettyp(pdt), rn); 2564 rt = pdt; 2565 } 2566 rtp = ln->tn_type; 2567 } else if (rt == PTR && isityp(lt)) { 2568 if (lt != pdt) { 2569 ln = convert(NOOP, 0, gettyp(pdt), ln); 2570 lt = pdt; 2571 } 2572 rtp = rn->tn_type; 2573 } else if (lt == PTR && ln->tn_type->t_subt->t_tspec == VOID) { 2574 if (rt != PTR) 2575 LERROR("bldcol()"); 2576 rtp = ln->tn_type; 2577 mrgqual(&rtp, ln->tn_type, rn->tn_type); 2578 } else if (rt == PTR && rn->tn_type->t_subt->t_tspec == VOID) { 2579 if (lt != PTR) 2580 LERROR("bldcol()"); 2581 rtp = rn->tn_type; 2582 mrgqual(&rtp, ln->tn_type, rn->tn_type); 2583 } else { 2584 if (lt != PTR || rt != PTR) 2585 LERROR("bldcol()"); 2586 /* 2587 * XXX For now we simply take the left type. This is 2588 * probably wrong, if one type contains a functionprototype 2589 * and the other one, at the same place, only an old style 2590 * declaration. 2591 */ 2592 rtp = ln->tn_type; 2593 mrgqual(&rtp, ln->tn_type, rn->tn_type); 2594 } 2595 2596 ntn = mktnode(COLON, rtp, ln, rn); 2597 2598 return (ntn); 2599 } 2600 2601 /* 2602 * Create a node for an assignment operator (both = and op= ). 2603 */ 2604 static tnode_t * 2605 bldasgn(op_t op, tnode_t *ln, tnode_t *rn) 2606 { 2607 tspec_t lt, rt; 2608 tnode_t *ntn, *ctn; 2609 2610 if (ln == NULL || rn == NULL) 2611 LERROR("bldasgn()"); 2612 2613 lt = ln->tn_type->t_tspec; 2614 rt = rn->tn_type->t_tspec; 2615 2616 if ((op == ADDASS || op == SUBASS) && lt == PTR) { 2617 if (!isityp(rt)) 2618 LERROR("bldasgn()"); 2619 ctn = plength(ln->tn_type); 2620 if (rn->tn_type->t_tspec != ctn->tn_type->t_tspec) 2621 rn = convert(NOOP, 0, ctn->tn_type, rn); 2622 rn = mktnode(MULT, rn->tn_type, rn, ctn); 2623 if (rn->tn_left->tn_op == CON) 2624 rn = fold(rn); 2625 } 2626 2627 if ((op == ASSIGN || op == RETURN) && (lt == STRUCT || rt == STRUCT)) { 2628 if (rt != lt || ln->tn_type->t_str != rn->tn_type->t_str) 2629 LERROR("bldasgn()"); 2630 if (incompl(ln->tn_type)) { 2631 if (op == RETURN) { 2632 /* cannot return incomplete type */ 2633 error(212); 2634 } else { 2635 /* unknown operand size, op %s */ 2636 error(138, modtab[op].m_name); 2637 } 2638 return (NULL); 2639 } 2640 } 2641 2642 if (op == SHLASS) { 2643 if (psize(lt) < psize(rt)) { 2644 if (hflag) 2645 /* semantics of %s change in ANSI C; use ... */ 2646 warning(118, "<<="); 2647 } 2648 } else if (op != SHRASS) { 2649 if (op == ASSIGN || lt != PTR) { 2650 if (lt != rt || 2651 (ln->tn_type->t_isfield && rn->tn_op == CON)) { 2652 rn = convert(op, 0, ln->tn_type, rn); 2653 rt = lt; 2654 } 2655 } 2656 } 2657 2658 ntn = mktnode(op, ln->tn_type, ln, rn); 2659 2660 return (ntn); 2661 } 2662 2663 /* 2664 * Get length of type tp->t_subt. 2665 */ 2666 static tnode_t * 2667 plength(type_t *tp) 2668 { 2669 int elem, elsz; 2670 tspec_t st; 2671 2672 if (tp->t_tspec != PTR) 2673 LERROR("plength()"); 2674 tp = tp->t_subt; 2675 2676 elem = 1; 2677 elsz = 0; 2678 2679 while (tp->t_tspec == ARRAY) { 2680 elem *= tp->t_dim; 2681 tp = tp->t_subt; 2682 } 2683 2684 switch (tp->t_tspec) { 2685 case FUNC: 2686 /* pointer to function is not allowed here */ 2687 error(110); 2688 break; 2689 case VOID: 2690 /* cannot do pointer arithmetic on operand of ... */ 2691 (void)gnuism(136); 2692 break; 2693 case STRUCT: 2694 case UNION: 2695 if ((elsz = tp->t_str->size) == 0) 2696 /* cannot do pointer arithmetic on operand of ... */ 2697 error(136); 2698 break; 2699 case ENUM: 2700 if (incompl(tp)) { 2701 /* cannot do pointer arithmetic on operand of ... */ 2702 warning(136); 2703 } 2704 /* FALLTHROUGH */ 2705 default: 2706 if ((elsz = size(tp->t_tspec)) == 0) { 2707 /* cannot do pointer arithmetic on operand of ... */ 2708 error(136); 2709 } else if (elsz == -1) { 2710 LERROR("plength()"); 2711 } 2712 break; 2713 } 2714 2715 if (elem == 0 && elsz != 0) { 2716 /* cannot do pointer arithmetic on operand of ... */ 2717 error(136); 2718 } 2719 2720 if (elsz == 0) 2721 elsz = CHAR_BIT; 2722 2723 #if PTRDIFF_IS_LONG 2724 st = LONG; 2725 #else 2726 st = INT; 2727 #endif 2728 2729 return (getinode(st, (int64_t)(elem * elsz / CHAR_BIT))); 2730 } 2731 2732 /* 2733 * XXX 2734 * Note: There appear to be a number of bugs in detecting overflow in 2735 * this function. An audit and a set of proper regression tests are needed. 2736 * --Perry Metzger, Nov. 16, 2001 2737 */ 2738 /* 2739 * Do only as much as necessary to compute constant expressions. 2740 * Called only if the operator allows folding and (both) operands 2741 * are constants. 2742 */ 2743 static tnode_t * 2744 fold(tnode_t *tn) 2745 { 2746 val_t *v; 2747 tspec_t t; 2748 int utyp, ovfl; 2749 int64_t sl, sr = 0, q = 0, mask; 2750 uint64_t ul, ur = 0; 2751 tnode_t *cn; 2752 2753 v = xcalloc(1, sizeof (val_t)); 2754 v->v_tspec = t = tn->tn_type->t_tspec; 2755 2756 utyp = t == PTR || isutyp(t); 2757 ul = sl = tn->tn_left->tn_val->v_quad; 2758 if (modtab[tn->tn_op].m_binary) 2759 ur = sr = tn->tn_right->tn_val->v_quad; 2760 2761 mask = qlmasks[size(t)]; 2762 ovfl = 0; 2763 2764 switch (tn->tn_op) { 2765 case UPLUS: 2766 q = sl; 2767 break; 2768 case UMINUS: 2769 q = -sl; 2770 if (msb(q, t, -1) == msb(sl, t, -1)) 2771 ovfl = 1; 2772 break; 2773 case COMPL: 2774 q = ~sl; 2775 break; 2776 case MULT: 2777 if (utyp) { 2778 q = ul * ur; 2779 if (q != (q & mask)) 2780 ovfl = 1; 2781 else if ((ul != 0) && ((q / ul) != ur)) 2782 ovfl = 1; 2783 } else { 2784 q = sl * sr; 2785 if (msb(q, t, -1) != (msb(sl, t, -1) ^ msb(sr, t, -1))) 2786 ovfl = 1; 2787 } 2788 break; 2789 case DIV: 2790 if (sr == 0) { 2791 /* division by 0 */ 2792 error(139); 2793 q = utyp ? UQUAD_MAX : QUAD_MAX; 2794 } else { 2795 q = utyp ? (int64_t)(ul / ur) : sl / sr; 2796 } 2797 break; 2798 case MOD: 2799 if (sr == 0) { 2800 /* modulus by 0 */ 2801 error(140); 2802 q = 0; 2803 } else { 2804 q = utyp ? (int64_t)(ul % ur) : sl % sr; 2805 } 2806 break; 2807 case PLUS: 2808 q = utyp ? (int64_t)(ul + ur) : sl + sr; 2809 if (msb(sl, t, -1) != 0 && msb(sr, t, -1) != 0) { 2810 if (msb(q, t, -1) == 0) 2811 ovfl = 1; 2812 } else if (msb(sl, t, -1) == 0 && msb(sr, t, -1) == 0) { 2813 if (msb(q, t, -1) != 0) 2814 ovfl = 1; 2815 } 2816 break; 2817 case MINUS: 2818 q = utyp ? (int64_t)(ul - ur) : sl - sr; 2819 if (msb(sl, t, -1) != 0 && msb(sr, t, -1) == 0) { 2820 if (msb(q, t, -1) == 0) 2821 ovfl = 1; 2822 } else if (msb(sl, t, -1) == 0 && msb(sr, t, -1) != 0) { 2823 if (msb(q, t, -1) != 0) 2824 ovfl = 1; 2825 } 2826 break; 2827 case SHL: 2828 q = utyp ? (int64_t)(ul << sr) : sl << sr; 2829 break; 2830 case SHR: 2831 /* 2832 * The sign must be explicitly extended because 2833 * shifts of signed values are implementation dependent. 2834 */ 2835 q = ul >> sr; 2836 q = xsign(q, t, size(t) - (int)sr); 2837 break; 2838 case LT: 2839 q = utyp ? ul < ur : sl < sr; 2840 break; 2841 case LE: 2842 q = utyp ? ul <= ur : sl <= sr; 2843 break; 2844 case GE: 2845 q = utyp ? ul >= ur : sl >= sr; 2846 break; 2847 case GT: 2848 q = utyp ? ul > ur : sl > sr; 2849 break; 2850 case EQ: 2851 q = utyp ? ul == ur : sl == sr; 2852 break; 2853 case NE: 2854 q = utyp ? ul != ur : sl != sr; 2855 break; 2856 case AND: 2857 q = utyp ? (int64_t)(ul & ur) : sl & sr; 2858 break; 2859 case XOR: 2860 q = utyp ? (int64_t)(ul ^ ur) : sl ^ sr; 2861 break; 2862 case OR: 2863 q = utyp ? (int64_t)(ul | ur) : sl | sr; 2864 break; 2865 default: 2866 LERROR("fold()"); 2867 } 2868 2869 /* XXX does not work for quads. */ 2870 if (ovfl || ((uint64_t)(q | mask) != ~(uint64_t)0 && 2871 (q & ~mask) != 0)) { 2872 if (hflag) 2873 /* integer overflow detected, op %s */ 2874 warning(141, modtab[tn->tn_op].m_name); 2875 } 2876 2877 v->v_quad = xsign(q, t, -1); 2878 2879 cn = getcnode(tn->tn_type, v); 2880 2881 return (cn); 2882 } 2883 2884 /* 2885 * Same for operators whose operands are compared with 0 (test context). 2886 */ 2887 static tnode_t * 2888 foldtst(tnode_t *tn) 2889 { 2890 int l, r = 0; 2891 val_t *v; 2892 2893 v = xcalloc(1, sizeof (val_t)); 2894 v->v_tspec = tn->tn_type->t_tspec; 2895 if (tn->tn_type->t_tspec != INT) 2896 LERROR("foldtst()"); 2897 2898 if (isftyp(tn->tn_left->tn_type->t_tspec)) { 2899 l = tn->tn_left->tn_val->v_ldbl != 0.0; 2900 } else { 2901 l = tn->tn_left->tn_val->v_quad != 0; 2902 } 2903 2904 if (modtab[tn->tn_op].m_binary) { 2905 if (isftyp(tn->tn_right->tn_type->t_tspec)) { 2906 r = tn->tn_right->tn_val->v_ldbl != 0.0; 2907 } else { 2908 r = tn->tn_right->tn_val->v_quad != 0; 2909 } 2910 } 2911 2912 switch (tn->tn_op) { 2913 case NOT: 2914 if (hflag) 2915 /* constant argument to NOT */ 2916 warning(239); 2917 v->v_quad = !l; 2918 break; 2919 case LOGAND: 2920 v->v_quad = l && r; 2921 break; 2922 case LOGOR: 2923 v->v_quad = l || r; 2924 break; 2925 default: 2926 LERROR("foldtst()"); 2927 } 2928 2929 return (getcnode(tn->tn_type, v)); 2930 } 2931 2932 /* 2933 * Same for operands with floating point type. 2934 */ 2935 static tnode_t * 2936 foldflt(tnode_t *tn) 2937 { 2938 val_t *v; 2939 tspec_t t; 2940 ldbl_t l, r = 0; 2941 2942 fpe = 0; 2943 v = xcalloc(1, sizeof (val_t)); 2944 v->v_tspec = t = tn->tn_type->t_tspec; 2945 2946 if (!isftyp(t)) 2947 LERROR("foldflt()"); 2948 2949 if (t != tn->tn_left->tn_type->t_tspec) 2950 LERROR("foldflt()"); 2951 if (modtab[tn->tn_op].m_binary && t != tn->tn_right->tn_type->t_tspec) 2952 LERROR("foldflt()"); 2953 2954 l = tn->tn_left->tn_val->v_ldbl; 2955 if (modtab[tn->tn_op].m_binary) 2956 r = tn->tn_right->tn_val->v_ldbl; 2957 2958 switch (tn->tn_op) { 2959 case UPLUS: 2960 v->v_ldbl = l; 2961 break; 2962 case UMINUS: 2963 v->v_ldbl = -l; 2964 break; 2965 case MULT: 2966 v->v_ldbl = l * r; 2967 break; 2968 case DIV: 2969 if (r == 0.0) { 2970 /* division by 0 */ 2971 error(139); 2972 if (t == FLOAT) { 2973 v->v_ldbl = l < 0 ? -FLT_MAX : FLT_MAX; 2974 } else if (t == DOUBLE) { 2975 v->v_ldbl = l < 0 ? -DBL_MAX : DBL_MAX; 2976 } else { 2977 v->v_ldbl = l < 0 ? -LDBL_MAX : LDBL_MAX; 2978 } 2979 } else { 2980 v->v_ldbl = l / r; 2981 } 2982 break; 2983 case PLUS: 2984 v->v_ldbl = l + r; 2985 break; 2986 case MINUS: 2987 v->v_ldbl = l - r; 2988 break; 2989 case LT: 2990 v->v_quad = l < r; 2991 break; 2992 case LE: 2993 v->v_quad = l <= r; 2994 break; 2995 case GE: 2996 v->v_quad = l >= r; 2997 break; 2998 case GT: 2999 v->v_quad = l > r; 3000 break; 3001 case EQ: 3002 v->v_quad = l == r; 3003 break; 3004 case NE: 3005 v->v_quad = l != r; 3006 break; 3007 default: 3008 LERROR("foldflt()"); 3009 } 3010 3011 if (!fpe && isnan((double)v->v_ldbl)) 3012 LERROR("foldflt()"); 3013 if (fpe || !finite((double)v->v_ldbl) || 3014 (t == FLOAT && 3015 (v->v_ldbl > FLT_MAX || v->v_ldbl < -FLT_MAX)) || 3016 (t == DOUBLE && 3017 (v->v_ldbl > DBL_MAX || v->v_ldbl < -DBL_MAX))) { 3018 /* floating point overflow detected, op %s */ 3019 warning(142, modtab[tn->tn_op].m_name); 3020 if (t == FLOAT) { 3021 v->v_ldbl = v->v_ldbl < 0 ? -FLT_MAX : FLT_MAX; 3022 } else if (t == DOUBLE) { 3023 v->v_ldbl = v->v_ldbl < 0 ? -DBL_MAX : DBL_MAX; 3024 } else { 3025 v->v_ldbl = v->v_ldbl < 0 ? -LDBL_MAX: LDBL_MAX; 3026 } 3027 fpe = 0; 3028 } 3029 3030 return (getcnode(tn->tn_type, v)); 3031 } 3032 3033 /* 3034 * Create a constant node for sizeof. 3035 */ 3036 tnode_t * 3037 bldszof(type_t *tp) 3038 { 3039 int elem, elsz; 3040 tspec_t st; 3041 3042 elem = 1; 3043 while (tp->t_tspec == ARRAY) { 3044 elem *= tp->t_dim; 3045 tp = tp->t_subt; 3046 } 3047 if (elem == 0) { 3048 /* cannot take size of incomplete type */ 3049 error(143); 3050 elem = 1; 3051 } 3052 switch (tp->t_tspec) { 3053 case FUNC: 3054 /* cannot take size of function */ 3055 error(144); 3056 elsz = 1; 3057 break; 3058 case STRUCT: 3059 case UNION: 3060 if (incompl(tp)) { 3061 /* cannot take size of incomplete type */ 3062 error(143); 3063 elsz = 1; 3064 } else { 3065 elsz = tp->t_str->size; 3066 } 3067 break; 3068 case ENUM: 3069 if (incompl(tp)) { 3070 /* cannot take size of incomplete type */ 3071 warning(143); 3072 } 3073 /* FALLTHROUGH */ 3074 default: 3075 if (tp->t_isfield) { 3076 /* cannot take size of bit-field */ 3077 error(145); 3078 } 3079 if (tp->t_tspec == VOID) { 3080 /* cannot take size of void */ 3081 error(146); 3082 elsz = 1; 3083 } else { 3084 elsz = size(tp->t_tspec); 3085 if (elsz <= 0) 3086 LERROR("bldszof()"); 3087 } 3088 break; 3089 } 3090 3091 #if SIZEOF_IS_ULONG 3092 st = ULONG; 3093 #else 3094 st = UINT; 3095 #endif 3096 3097 return (getinode(st, (int64_t)(elem * elsz / CHAR_BIT))); 3098 } 3099 3100 /* 3101 */ 3102 tnode_t * 3103 bldalof(type_t *tp) 3104 { 3105 tspec_t st; 3106 3107 switch (tp->t_tspec) { 3108 case ARRAY: 3109 break; 3110 3111 case FUNC: 3112 /* cannot take align of function */ 3113 error(144); 3114 return 0; 3115 3116 case STRUCT: 3117 case UNION: 3118 if (incompl(tp)) { 3119 /* cannot take align of incomplete type */ 3120 error(143); 3121 return 0; 3122 } 3123 break; 3124 case ENUM: 3125 break; 3126 default: 3127 if (tp->t_isfield) { 3128 /* cannot take align of bit-field */ 3129 error(145); 3130 return 0; 3131 } 3132 if (tp->t_tspec == VOID) { 3133 /* cannot take alignsize of void */ 3134 error(146); 3135 return 0; 3136 } 3137 break; 3138 } 3139 3140 #if SIZEOF_IS_ULONG 3141 st = ULONG; 3142 #else 3143 st = UINT; 3144 #endif 3145 3146 return getinode(st, (int64_t)getbound(tp)); 3147 } 3148 3149 /* 3150 * Type casts. 3151 */ 3152 tnode_t * 3153 cast(tnode_t *tn, type_t *tp) 3154 { 3155 tspec_t nt, ot; 3156 3157 if (tn == NULL) 3158 return (NULL); 3159 3160 tn = cconv(tn); 3161 3162 nt = tp->t_tspec; 3163 ot = tn->tn_type->t_tspec; 3164 3165 if (nt == VOID) { 3166 /* 3167 * XXX ANSI C requires scalar types or void (Plauger&Brodie). 3168 * But this seams really questionable. 3169 */ 3170 } else if (nt == STRUCT || nt == UNION || nt == ARRAY || nt == FUNC) { 3171 /* invalid cast expression */ 3172 error(147); 3173 return (NULL); 3174 } else if (ot == STRUCT || ot == UNION) { 3175 /* invalid cast expression */ 3176 error(147); 3177 return (NULL); 3178 } else if (ot == VOID) { 3179 /* improper cast of void expression */ 3180 error(148); 3181 return (NULL); 3182 } else if (isityp(nt) && issclt(ot)) { 3183 /* ok */ 3184 } else if (isftyp(nt) && isatyp(ot)) { 3185 /* ok */ 3186 } else if (nt == PTR && isityp(ot)) { 3187 /* ok */ 3188 } else if (nt == PTR && ot == PTR) { 3189 if (!tp->t_subt->t_const && tn->tn_type->t_subt->t_const) { 3190 if (hflag) 3191 /* cast discards 'const' from ... */ 3192 warning(275); 3193 } 3194 } else { 3195 /* invalid cast expression */ 3196 error(147); 3197 return (NULL); 3198 } 3199 3200 tn = convert(CVT, 0, tp, tn); 3201 tn->tn_cast = 1; 3202 3203 return (tn); 3204 } 3205 3206 /* 3207 * Create the node for a function argument. 3208 * All necessary conversions and type checks are done in funccall(), because 3209 * in funcarg() we have no information about expected argument types. 3210 */ 3211 tnode_t * 3212 funcarg(tnode_t *args, tnode_t *arg) 3213 { 3214 tnode_t *ntn; 3215 3216 /* 3217 * If there was a serious error in the expression for the argument, 3218 * create a dummy argument so the positions of the remaining arguments 3219 * will not change. 3220 */ 3221 if (arg == NULL) 3222 arg = getinode(INT, (int64_t)0); 3223 3224 ntn = mktnode(PUSH, arg->tn_type, arg, args); 3225 3226 return (ntn); 3227 } 3228 3229 /* 3230 * Create the node for a function call. Also check types of 3231 * function arguments and insert conversions, if necessary. 3232 */ 3233 tnode_t * 3234 funccall(tnode_t *func, tnode_t *args) 3235 { 3236 tnode_t *ntn; 3237 op_t fcop; 3238 3239 if (func == NULL) 3240 return (NULL); 3241 3242 if (func->tn_op == NAME && func->tn_type->t_tspec == FUNC) { 3243 fcop = CALL; 3244 } else { 3245 fcop = ICALL; 3246 } 3247 3248 /* 3249 * after cconv() func will always be a pointer to a function 3250 * if it is a valid function designator. 3251 */ 3252 func = cconv(func); 3253 3254 if (func->tn_type->t_tspec != PTR || 3255 func->tn_type->t_subt->t_tspec != FUNC) { 3256 /* illegal function */ 3257 error(149); 3258 return (NULL); 3259 } 3260 3261 args = chkfarg(func->tn_type->t_subt, args); 3262 3263 ntn = mktnode(fcop, func->tn_type->t_subt->t_subt, func, args); 3264 3265 return (ntn); 3266 } 3267 3268 /* 3269 * Check types of all function arguments and insert conversions, 3270 * if necessary. 3271 */ 3272 static tnode_t * 3273 chkfarg(type_t *ftp, tnode_t *args) 3274 { 3275 tnode_t *arg; 3276 sym_t *asym; 3277 tspec_t at; 3278 int narg, npar, n, i; 3279 3280 /* get # of args in the prototype */ 3281 npar = 0; 3282 for (asym = ftp->t_args; asym != NULL; asym = asym->s_nxt) 3283 npar++; 3284 3285 /* get # of args in function call */ 3286 narg = 0; 3287 for (arg = args; arg != NULL; arg = arg->tn_right) 3288 narg++; 3289 3290 asym = ftp->t_args; 3291 if (ftp->t_proto && npar != narg && !(ftp->t_vararg && npar < narg)) { 3292 /* argument mismatch: %d arg%s passed, %d expected */ 3293 error(150, narg, narg > 1 ? "s" : "", npar); 3294 asym = NULL; 3295 } 3296 3297 for (n = 1; n <= narg; n++) { 3298 3299 /* 3300 * The rightmost argument is at the top of the argument 3301 * subtree. 3302 */ 3303 for (i = narg, arg = args; i > n; i--, arg = arg->tn_right) 3304 continue; 3305 3306 /* some things which are always not allowd */ 3307 if ((at = arg->tn_left->tn_type->t_tspec) == VOID) { 3308 /* void expressions may not be arguments, arg #%d */ 3309 error(151, n); 3310 return (NULL); 3311 } else if ((at == STRUCT || at == UNION) && 3312 incompl(arg->tn_left->tn_type)) { 3313 /* argument cannot have unknown size, arg #%d */ 3314 error(152, n); 3315 return (NULL); 3316 } else if (isityp(at) && arg->tn_left->tn_type->t_isenum && 3317 incompl(arg->tn_left->tn_type)) { 3318 /* argument cannot have unknown size, arg #%d */ 3319 warning(152, n); 3320 } 3321 3322 /* class conversions (arg in value context) */ 3323 arg->tn_left = cconv(arg->tn_left); 3324 3325 if (asym != NULL) { 3326 arg->tn_left = parg(n, asym->s_type, arg->tn_left); 3327 } else { 3328 arg->tn_left = promote(NOOP, 1, arg->tn_left); 3329 } 3330 arg->tn_type = arg->tn_left->tn_type; 3331 3332 if (asym != NULL) 3333 asym = asym->s_nxt; 3334 } 3335 3336 return (args); 3337 } 3338 3339 /* 3340 * Compare the type of an argument with the corresponding type of a 3341 * prototype parameter. If it is a valid combination, but both types 3342 * are not the same, insert a conversion to convert the argument into 3343 * the type of the parameter. 3344 */ 3345 static tnode_t * 3346 parg( int n, /* pos of arg */ 3347 type_t *tp, /* expected type (from prototype) */ 3348 tnode_t *tn) /* argument */ 3349 { 3350 tnode_t *ln; 3351 int dowarn; 3352 3353 ln = xcalloc(1, sizeof (tnode_t)); 3354 ln->tn_type = tduptyp(tp); 3355 ln->tn_type->t_const = 0; 3356 ln->tn_lvalue = 1; 3357 if (typeok(FARG, n, ln, tn)) { 3358 if (!eqtype(tp, tn->tn_type, 1, 0, (dowarn = 0, &dowarn)) || dowarn) 3359 tn = convert(FARG, n, tp, tn); 3360 } 3361 free(ln); 3362 return (tn); 3363 } 3364 3365 /* 3366 * Return the value of an integral constant expression. 3367 * If the expression is not constant or its type is not an integer 3368 * type, an error message is printed. 3369 */ 3370 val_t * 3371 constant(tnode_t *tn, int required) 3372 { 3373 val_t *v; 3374 3375 if (tn != NULL) 3376 tn = cconv(tn); 3377 if (tn != NULL) 3378 tn = promote(NOOP, 0, tn); 3379 3380 v = xcalloc(1, sizeof (val_t)); 3381 3382 if (tn == NULL) { 3383 if (nerr == 0) 3384 LERROR("constant()"); 3385 v->v_tspec = INT; 3386 v->v_quad = 1; 3387 return (v); 3388 } 3389 3390 v->v_tspec = tn->tn_type->t_tspec; 3391 3392 if (tn->tn_op == CON) { 3393 if (tn->tn_type->t_tspec != tn->tn_val->v_tspec) 3394 LERROR("constant()"); 3395 if (isityp(tn->tn_val->v_tspec)) { 3396 v->v_ansiu = tn->tn_val->v_ansiu; 3397 v->v_quad = tn->tn_val->v_quad; 3398 return (v); 3399 } 3400 v->v_quad = tn->tn_val->v_ldbl; 3401 } else { 3402 v->v_quad = 1; 3403 } 3404 3405 /* integral constant expression expected */ 3406 if (required) 3407 error(55); 3408 else 3409 c99ism(318); 3410 3411 if (!isityp(v->v_tspec)) 3412 v->v_tspec = INT; 3413 3414 return (v); 3415 } 3416 3417 /* 3418 * Perform some tests on expressions which can't be done in build() and 3419 * functions called by build(). These tests must be done here because 3420 * we need some information about the context in which the operations 3421 * are performed. 3422 * After all tests are performed, expr() frees the memory which is used 3423 * for the expression. 3424 */ 3425 void 3426 expr(tnode_t *tn, int vctx, int tctx, int dofreeblk) 3427 { 3428 3429 if (tn == NULL && nerr == 0) 3430 LERROR("expr()"); 3431 3432 if (tn == NULL) { 3433 tfreeblk(); 3434 return; 3435 } 3436 3437 /* expr() is also called in global initialisations */ 3438 if (dcs->d_ctx != EXTERN) 3439 chkreach(); 3440 3441 chkmisc(tn, vctx, tctx, !tctx, 0, 0, 0); 3442 if (tn->tn_op == ASSIGN) { 3443 if (hflag && tctx) 3444 /* assignment in conditional context */ 3445 warning(159); 3446 } else if (tn->tn_op == CON) { 3447 if (hflag && tctx && !ccflg) 3448 /* constant in conditional context */ 3449 warning(161); 3450 } 3451 if (!modtab[tn->tn_op].m_sideeff) { 3452 /* 3453 * for left operands of COMMA this warning is already 3454 * printed 3455 */ 3456 if (tn->tn_op != COMMA && !vctx && !tctx) 3457 nulleff(tn); 3458 } 3459 if (dflag) 3460 displexpr(tn, 0); 3461 3462 /* free the tree memory */ 3463 if (dofreeblk) 3464 tfreeblk(); 3465 } 3466 3467 static void 3468 nulleff(tnode_t *tn) 3469 { 3470 3471 if (!hflag) 3472 return; 3473 3474 while (!modtab[tn->tn_op].m_sideeff) { 3475 if (tn->tn_op == CVT && tn->tn_type->t_tspec == VOID) { 3476 tn = tn->tn_left; 3477 } else if (tn->tn_op == LOGAND || tn->tn_op == LOGOR) { 3478 /* 3479 * && and || have a side effect if the right operand 3480 * has a side effect. 3481 */ 3482 tn = tn->tn_right; 3483 } else if (tn->tn_op == QUEST) { 3484 /* 3485 * ? has a side effect if at least one of its right 3486 * operands has a side effect 3487 */ 3488 tn = tn->tn_right; 3489 } else if (tn->tn_op == COLON || tn->tn_op == COMMA) { 3490 /* 3491 * : has a side effect if at least one of its operands 3492 * has a side effect 3493 */ 3494 if (modtab[tn->tn_left->tn_op].m_sideeff) { 3495 tn = tn->tn_left; 3496 } else if (modtab[tn->tn_right->tn_op].m_sideeff) { 3497 tn = tn->tn_right; 3498 } else { 3499 break; 3500 } 3501 } else { 3502 break; 3503 } 3504 } 3505 if (!modtab[tn->tn_op].m_sideeff) 3506 /* expression has null effect */ 3507 warning(129); 3508 } 3509 3510 /* 3511 * Dump an expression to stdout 3512 * only used for debugging 3513 */ 3514 static void 3515 displexpr(tnode_t *tn, int offs) 3516 { 3517 uint64_t uq; 3518 3519 if (tn == NULL) { 3520 (void)printf("%*s%s\n", offs, "", "NULL"); 3521 return; 3522 } 3523 (void)printf("%*sop %s ", offs, "", modtab[tn->tn_op].m_name); 3524 3525 if (tn->tn_op == NAME) { 3526 (void)printf("%s: %s ", 3527 tn->tn_sym->s_name, scltoa(tn->tn_sym->s_scl)); 3528 } else if (tn->tn_op == CON && isftyp(tn->tn_type->t_tspec)) { 3529 (void)printf("%#g ", (double)tn->tn_val->v_ldbl); 3530 } else if (tn->tn_op == CON && isityp(tn->tn_type->t_tspec)) { 3531 uq = tn->tn_val->v_quad; 3532 (void)printf("0x %08lx %08lx ", (long)(uq >> 32) & 0xffffffffl, 3533 (long)uq & 0xffffffffl); 3534 } else if (tn->tn_op == CON) { 3535 if (tn->tn_type->t_tspec != PTR) 3536 LERROR("displexpr()"); 3537 (void)printf("0x%0*lx ", (int)(sizeof (void *) * CHAR_BIT / 4), 3538 (u_long)tn->tn_val->v_quad); 3539 } else if (tn->tn_op == STRING) { 3540 if (tn->tn_strg->st_tspec == CHAR) { 3541 (void)printf("\"%s\"", tn->tn_strg->st_cp); 3542 } else { 3543 char *s; 3544 size_t n; 3545 n = MB_CUR_MAX * (tn->tn_strg->st_len + 1); 3546 s = xmalloc(n); 3547 (void)wcstombs(s, tn->tn_strg->st_wcp, n); 3548 (void)printf("L\"%s\"", s); 3549 free(s); 3550 } 3551 (void)printf(" "); 3552 } else if (tn->tn_op == FSEL) { 3553 (void)printf("o=%d, l=%d ", tn->tn_type->t_foffs, 3554 tn->tn_type->t_flen); 3555 } 3556 (void)printf("%s\n", ttos(tn->tn_type)); 3557 if (tn->tn_op == NAME || tn->tn_op == CON || tn->tn_op == STRING) 3558 return; 3559 displexpr(tn->tn_left, offs + 2); 3560 if (modtab[tn->tn_op].m_binary || 3561 (tn->tn_op == PUSH && tn->tn_right != NULL)) { 3562 displexpr(tn->tn_right, offs + 2); 3563 } 3564 } 3565 3566 /* 3567 * Called by expr() to recursively perform some tests. 3568 */ 3569 /* ARGSUSED */ 3570 void 3571 chkmisc(tnode_t *tn, int vctx, int tctx, int eqwarn, int fcall, int rvdisc, 3572 int szof) 3573 { 3574 tnode_t *ln, *rn; 3575 mod_t *mp; 3576 int nrvdisc, cvctx, ctctx; 3577 op_t op; 3578 scl_t sc; 3579 dinfo_t *di; 3580 3581 if (tn == NULL) 3582 return; 3583 3584 ln = tn->tn_left; 3585 rn = tn->tn_right; 3586 mp = &modtab[op = tn->tn_op]; 3587 3588 switch (op) { 3589 case AMPER: 3590 if (ln->tn_op == NAME && (reached || rchflg)) { 3591 if (!szof) 3592 setsflg(ln->tn_sym); 3593 setuflg(ln->tn_sym, fcall, szof); 3594 } 3595 if (ln->tn_op == STAR && ln->tn_left->tn_op == PLUS) 3596 /* check the range of array indices */ 3597 chkaidx(ln->tn_left, 1); 3598 break; 3599 case LOAD: 3600 if (ln->tn_op == STAR && ln->tn_left->tn_op == PLUS) 3601 /* check the range of array indices */ 3602 chkaidx(ln->tn_left, 0); 3603 /* FALLTHROUGH */ 3604 case PUSH: 3605 case INCBEF: 3606 case DECBEF: 3607 case INCAFT: 3608 case DECAFT: 3609 case ADDASS: 3610 case SUBASS: 3611 case MULASS: 3612 case DIVASS: 3613 case MODASS: 3614 case ANDASS: 3615 case ORASS: 3616 case XORASS: 3617 case SHLASS: 3618 case SHRASS: 3619 case REAL: 3620 case IMAG: 3621 if (ln->tn_op == NAME && (reached || rchflg)) { 3622 sc = ln->tn_sym->s_scl; 3623 /* 3624 * Look if there was a asm statement in one of the 3625 * compound statements we are in. If not, we don't 3626 * print a warning. 3627 */ 3628 for (di = dcs; di != NULL; di = di->d_nxt) { 3629 if (di->d_asm) 3630 break; 3631 } 3632 if (sc != EXTERN && sc != STATIC && 3633 !ln->tn_sym->s_set && !szof && di == NULL) { 3634 /* %s may be used before set */ 3635 warning(158, ln->tn_sym->s_name); 3636 setsflg(ln->tn_sym); 3637 } 3638 setuflg(ln->tn_sym, 0, 0); 3639 } 3640 break; 3641 case ASSIGN: 3642 if (ln->tn_op == NAME && !szof && (reached || rchflg)) { 3643 setsflg(ln->tn_sym); 3644 if (ln->tn_sym->s_scl == EXTERN) 3645 outusg(ln->tn_sym); 3646 } 3647 if (ln->tn_op == STAR && ln->tn_left->tn_op == PLUS) 3648 /* check the range of array indices */ 3649 chkaidx(ln->tn_left, 0); 3650 break; 3651 case CALL: 3652 if (ln->tn_op != AMPER || ln->tn_left->tn_op != NAME) 3653 LERROR("chkmisc()"); 3654 if (!szof) 3655 outcall(tn, vctx || tctx, rvdisc); 3656 break; 3657 case EQ: 3658 /* equality operator "==" found where "=" was exp. */ 3659 if (hflag && eqwarn) 3660 warning(160); 3661 break; 3662 case CON: 3663 case NAME: 3664 case STRING: 3665 return; 3666 /* LINTED (enumeration values not handled in switch) */ 3667 case OR: 3668 case XOR: 3669 case NE: 3670 case GE: 3671 case GT: 3672 case LE: 3673 case LT: 3674 case SHR: 3675 case SHL: 3676 case MINUS: 3677 case PLUS: 3678 case MOD: 3679 case DIV: 3680 case MULT: 3681 case STAR: 3682 case UMINUS: 3683 case UPLUS: 3684 case DEC: 3685 case INC: 3686 case COMPL: 3687 case NOT: 3688 case POINT: 3689 case ARROW: 3690 case NOOP: 3691 case AND: 3692 case FARG: 3693 case CASE: 3694 case INIT: 3695 case RETURN: 3696 case ICALL: 3697 case CVT: 3698 case COMMA: 3699 case FSEL: 3700 case COLON: 3701 case QUEST: 3702 case LOGOR: 3703 case LOGAND: 3704 break; 3705 } 3706 3707 cvctx = mp->m_vctx; 3708 ctctx = mp->m_tctx; 3709 /* 3710 * values of operands of ':' are not used if the type of at least 3711 * one of the operands (for gcc compatibility) is void 3712 * XXX test/value context of QUEST should probably be used as 3713 * context for both operands of COLON 3714 */ 3715 if (op == COLON && tn->tn_type->t_tspec == VOID) 3716 cvctx = ctctx = 0; 3717 nrvdisc = op == CVT && tn->tn_type->t_tspec == VOID; 3718 chkmisc(ln, cvctx, ctctx, mp->m_eqwarn, op == CALL, nrvdisc, szof); 3719 3720 switch (op) { 3721 case PUSH: 3722 if (rn != NULL) 3723 chkmisc(rn, 0, 0, mp->m_eqwarn, 0, 0, szof); 3724 break; 3725 case LOGAND: 3726 case LOGOR: 3727 chkmisc(rn, 0, 1, mp->m_eqwarn, 0, 0, szof); 3728 break; 3729 case COLON: 3730 chkmisc(rn, cvctx, ctctx, mp->m_eqwarn, 0, 0, szof); 3731 break; 3732 case COMMA: 3733 chkmisc(rn, vctx, tctx, mp->m_eqwarn, 0, 0, szof); 3734 break; 3735 default: 3736 if (mp->m_binary) 3737 chkmisc(rn, 1, 0, mp->m_eqwarn, 0, 0, szof); 3738 break; 3739 } 3740 3741 } 3742 3743 /* 3744 * Checks the range of array indices, if possible. 3745 * amper is set if only the address of the element is used. This 3746 * means that the index is allowd to refere to the first element 3747 * after the array. 3748 */ 3749 static void 3750 chkaidx(tnode_t *tn, int amper) 3751 { 3752 int dim; 3753 tnode_t *ln, *rn; 3754 int elsz; 3755 int64_t con; 3756 3757 ln = tn->tn_left; 3758 rn = tn->tn_right; 3759 3760 /* We can only check constant indices. */ 3761 if (rn->tn_op != CON) 3762 return; 3763 3764 /* Return if the left node does not stem from an array. */ 3765 if (ln->tn_op != AMPER) 3766 return; 3767 if (ln->tn_left->tn_op != STRING && ln->tn_left->tn_op != NAME) 3768 return; 3769 if (ln->tn_left->tn_type->t_tspec != ARRAY) 3770 return; 3771 3772 /* 3773 * For incomplete array types, we can print a warning only if 3774 * the index is negative. 3775 */ 3776 if (incompl(ln->tn_left->tn_type) && rn->tn_val->v_quad >= 0) 3777 return; 3778 3779 /* Get the size of one array element */ 3780 if ((elsz = length(ln->tn_type->t_subt, NULL)) == 0) 3781 return; 3782 elsz /= CHAR_BIT; 3783 3784 /* Change the unit of the index from bytes to element size. */ 3785 if (isutyp(rn->tn_type->t_tspec)) { 3786 con = (uint64_t)rn->tn_val->v_quad / elsz; 3787 } else { 3788 con = rn->tn_val->v_quad / elsz; 3789 } 3790 3791 dim = ln->tn_left->tn_type->t_dim + (amper ? 1 : 0); 3792 3793 if (!isutyp(rn->tn_type->t_tspec) && con < 0) { 3794 /* array subscript cannot be negative: %ld */ 3795 warning(167, (long)con); 3796 } else if (dim > 0 && (uint64_t)con >= (uint64_t)dim) { 3797 /* array subscript cannot be > %d: %ld */ 3798 warning(168, dim - 1, (long)con); 3799 } 3800 } 3801 3802 /* 3803 * Check for ordered comparisons of unsigned values with 0. 3804 */ 3805 static void 3806 chkcomp(op_t op, tnode_t *ln, tnode_t *rn) 3807 { 3808 char buf[64]; 3809 tspec_t lt, rt; 3810 mod_t *mp; 3811 3812 lt = ln->tn_type->t_tspec; 3813 rt = rn->tn_type->t_tspec; 3814 mp = &modtab[op]; 3815 3816 if (ln->tn_op != CON && rn->tn_op != CON) 3817 return; 3818 3819 if (!isityp(lt) || !isityp(rt)) 3820 return; 3821 3822 if ((hflag || pflag) && lt == CHAR && rn->tn_op == CON && 3823 (rn->tn_val->v_quad < 0 || 3824 rn->tn_val->v_quad > ~(~0 << (CHAR_BIT - 1)))) { 3825 /* nonportable character comparison, op %s */ 3826 warning(230, mp->m_name); 3827 return; 3828 } 3829 if ((hflag || pflag) && rt == CHAR && ln->tn_op == CON && 3830 (ln->tn_val->v_quad < 0 || 3831 ln->tn_val->v_quad > ~(~0 << (CHAR_BIT - 1)))) { 3832 /* nonportable character comparison, op %s */ 3833 warning(230, mp->m_name); 3834 return; 3835 } 3836 if (isutyp(lt) && !isutyp(rt) && 3837 rn->tn_op == CON && rn->tn_val->v_quad <= 0) { 3838 if (rn->tn_val->v_quad < 0) { 3839 /* comparison of %s with %s, op %s */ 3840 warning(162, tyname(buf, sizeof(buf), ln->tn_type), 3841 "negative constant", mp->m_name); 3842 } else if (op == LT || op == GE || (hflag && op == LE)) { 3843 /* comparison of %s with %s, op %s */ 3844 warning(162, tyname(buf, sizeof(buf), ln->tn_type), 3845 "0", mp->m_name); 3846 } 3847 return; 3848 } 3849 if (isutyp(rt) && !isutyp(lt) && 3850 ln->tn_op == CON && ln->tn_val->v_quad <= 0) { 3851 if (ln->tn_val->v_quad < 0) { 3852 /* comparison of %s with %s, op %s */ 3853 warning(162, "negative constant", 3854 tyname(buf, sizeof(buf), rn->tn_type), mp->m_name); 3855 } else if (op == GT || op == LE || (hflag && op == GE)) { 3856 /* comparison of %s with %s, op %s */ 3857 warning(162, "0", tyname(buf, sizeof(buf), rn->tn_type), 3858 mp->m_name); 3859 } 3860 return; 3861 } 3862 } 3863 3864 /* 3865 * Takes an expression an returns 0 if this expression can be used 3866 * for static initialisation, otherwise -1. 3867 * 3868 * Constant initialisation expressions must be constant or an address 3869 * of a static object with an optional offset. In the first case, 3870 * the result is returned in *offsp. In the second case, the static 3871 * object is returned in *symp and the offset in *offsp. 3872 * 3873 * The expression can consist of PLUS, MINUS, AMPER, NAME, STRING and 3874 * CON. Type conversions are allowed if they do not change binary 3875 * representation (including width). 3876 */ 3877 int 3878 conaddr(tnode_t *tn, sym_t **symp, ptrdiff_t *offsp) 3879 { 3880 sym_t *sym; 3881 ptrdiff_t offs1, offs2; 3882 tspec_t t, ot; 3883 3884 switch (tn->tn_op) { 3885 case MINUS: 3886 if (tn->tn_right->tn_op == CVT) 3887 return conaddr(tn->tn_right, symp, offsp); 3888 else if (tn->tn_right->tn_op != CON) 3889 return (-1); 3890 /* FALLTHROUGH */ 3891 case PLUS: 3892 offs1 = offs2 = 0; 3893 if (tn->tn_left->tn_op == CON) { 3894 offs1 = (ptrdiff_t)tn->tn_left->tn_val->v_quad; 3895 if (conaddr(tn->tn_right, &sym, &offs2) == -1) 3896 return (-1); 3897 } else if (tn->tn_right->tn_op == CON) { 3898 offs2 = (ptrdiff_t)tn->tn_right->tn_val->v_quad; 3899 if (tn->tn_op == MINUS) 3900 offs2 = -offs2; 3901 if (conaddr(tn->tn_left, &sym, &offs1) == -1) 3902 return (-1); 3903 } else { 3904 return (-1); 3905 } 3906 *symp = sym; 3907 *offsp = offs1 + offs2; 3908 break; 3909 case AMPER: 3910 if (tn->tn_left->tn_op == NAME) { 3911 *symp = tn->tn_left->tn_sym; 3912 *offsp = 0; 3913 } else if (tn->tn_left->tn_op == STRING) { 3914 /* 3915 * If this would be the front end of a compiler we 3916 * would return a label instead of 0. 3917 */ 3918 *offsp = 0; 3919 } 3920 break; 3921 case CVT: 3922 t = tn->tn_type->t_tspec; 3923 ot = tn->tn_left->tn_type->t_tspec; 3924 if ((!isityp(t) && t != PTR) || (!isityp(ot) && ot != PTR)) 3925 return (-1); 3926 #ifdef notdef 3927 /* 3928 * consider: 3929 * struct foo { 3930 * unsigned char a; 3931 * } f = { 3932 * (u_char)(u_long)(&(((struct foo *)0)->a)) 3933 * }; 3934 * since psize(u_long) != psize(u_char) this fails. 3935 */ 3936 else if (psize(t) != psize(ot)) 3937 return (-1); 3938 #endif 3939 if (conaddr(tn->tn_left, symp, offsp) == -1) 3940 return (-1); 3941 break; 3942 default: 3943 return (-1); 3944 } 3945 return (0); 3946 } 3947 3948 /* 3949 * Concatenate two string constants. 3950 */ 3951 strg_t * 3952 catstrg(strg_t *strg1, strg_t *strg2) 3953 { 3954 size_t len1, len2, len; 3955 3956 if (strg1->st_tspec != strg2->st_tspec) { 3957 /* cannot concatenate wide and regular string literals */ 3958 error(292); 3959 return (strg1); 3960 } 3961 3962 len = (len1 = strg1->st_len) + (len2 = strg2->st_len); 3963 3964 if (strg1->st_tspec == CHAR) { 3965 strg1->st_cp = xrealloc(strg1->st_cp, len + 1); 3966 (void)memcpy(strg1->st_cp + len1, strg2->st_cp, len2 + 1); 3967 free(strg2->st_cp); 3968 } else { 3969 strg1->st_wcp = xrealloc(strg1->st_wcp, 3970 (len + 1) * sizeof (wchar_t)); 3971 (void)memcpy(strg1->st_wcp + len1, strg2->st_wcp, 3972 (len2 + 1) * sizeof (wchar_t)); 3973 free(strg2->st_wcp); 3974 } 3975 free(strg2); 3976 3977 return (strg1); 3978 } 3979 3980 /* 3981 * Print a warning if the given node has operands which should be 3982 * parenthesized. 3983 * 3984 * XXX Does not work if an operand is a constant expression. Constant 3985 * expressions are already folded. 3986 */ 3987 static void 3988 precconf(tnode_t *tn) 3989 { 3990 tnode_t *ln, *rn; 3991 op_t lop, rop = NOOP; 3992 int lparn, rparn = 0; 3993 mod_t *mp; 3994 int dowarn; 3995 3996 if (!hflag) 3997 return; 3998 3999 mp = &modtab[tn->tn_op]; 4000 4001 lparn = 0; 4002 for (ln = tn->tn_left; ln->tn_op == CVT; ln = ln->tn_left) 4003 lparn |= ln->tn_parn; 4004 lparn |= ln->tn_parn; 4005 lop = ln->tn_op; 4006 4007 if (mp->m_binary) { 4008 rparn = 0; 4009 for (rn = tn->tn_right; tn->tn_op == CVT; rn = rn->tn_left) 4010 rparn |= rn->tn_parn; 4011 rparn |= rn->tn_parn; 4012 rop = rn->tn_op; 4013 } 4014 4015 dowarn = 0; 4016 4017 switch (tn->tn_op) { 4018 case SHL: 4019 case SHR: 4020 if (!lparn && (lop == PLUS || lop == MINUS)) { 4021 dowarn = 1; 4022 } else if (!rparn && (rop == PLUS || rop == MINUS)) { 4023 dowarn = 1; 4024 } 4025 break; 4026 case LOGOR: 4027 if (!lparn && lop == LOGAND) { 4028 dowarn = 1; 4029 } else if (!rparn && rop == LOGAND) { 4030 dowarn = 1; 4031 } 4032 break; 4033 case AND: 4034 case XOR: 4035 case OR: 4036 if (!lparn && lop != tn->tn_op) { 4037 if (lop == PLUS || lop == MINUS) { 4038 dowarn = 1; 4039 } else if (lop == AND || lop == XOR) { 4040 dowarn = 1; 4041 } 4042 } 4043 if (!dowarn && !rparn && rop != tn->tn_op) { 4044 if (rop == PLUS || rop == MINUS) { 4045 dowarn = 1; 4046 } else if (rop == AND || rop == XOR) { 4047 dowarn = 1; 4048 } 4049 } 4050 break; 4051 /* LINTED (enumeration values not handled in switch) */ 4052 case DECAFT: 4053 case XORASS: 4054 case SHLASS: 4055 case NOOP: 4056 case ARROW: 4057 case ORASS: 4058 case POINT: 4059 case NAME: 4060 case NOT: 4061 case COMPL: 4062 case CON: 4063 case INC: 4064 case STRING: 4065 case DEC: 4066 case INCBEF: 4067 case DECBEF: 4068 case INCAFT: 4069 case FSEL: 4070 case CALL: 4071 case COMMA: 4072 case CVT: 4073 case ICALL: 4074 case LOAD: 4075 case PUSH: 4076 case RETURN: 4077 case INIT: 4078 case CASE: 4079 case FARG: 4080 case SUBASS: 4081 case ADDASS: 4082 case MODASS: 4083 case DIVASS: 4084 case MULASS: 4085 case ASSIGN: 4086 case COLON: 4087 case QUEST: 4088 case LOGAND: 4089 case NE: 4090 case EQ: 4091 case GE: 4092 case GT: 4093 case LE: 4094 case LT: 4095 case MINUS: 4096 case PLUS: 4097 case MOD: 4098 case DIV: 4099 case MULT: 4100 case AMPER: 4101 case STAR: 4102 case UMINUS: 4103 case SHRASS: 4104 case UPLUS: 4105 case ANDASS: 4106 case REAL: 4107 case IMAG: 4108 break; 4109 } 4110 4111 if (dowarn) { 4112 /* precedence confusion possible: parenthesize! */ 4113 warning(169); 4114 } 4115 4116 } 4117