parse.c

   1 /*
   2  * Stupid C parser, version 1e-6.
   3  *
   4  * Let's see how hard this is to do.
   5  *
   6  * Copyright (C) 2003 Transmeta Corp.
   7  *               2003-2004 Linus Torvalds
   8  *
   9  *  Licensed under the Open Software License version 1.1
  10  */
  11
  12 #include <stdarg.h>
  13 #include <stdlib.h>
  14 #include <stdio.h>
  15 #include <string.h>
  16 #include <ctype.h>
  17 #include <unistd.h>
  18 #include <fcntl.h>
  19 #include <limits.h>
  20
  21 #include "lib.h"
  22 #include "allocate.h"
  23 #include "token.h"
  24 #include "parse.h"
  25 #include "symbol.h"
  26 #include "scope.h"
  27 #include "expression.h"
  28 #include "target.h"
  29
  30 #define warn_on_mixed (1)
  31
  32 static struct symbol_list **function_symbol_list;
  33 struct symbol_list *function_computed_target_list;
  34 struct statement_list *function_computed_goto_list;
  35
  36 static struct token *statement(struct token *token, struct statement **tree);
  37
  38 // Add a symbol to the list of function-local symbols
  39 static void fn_local_symbol(struct symbol *sym)
  40 {
  41         if (function_symbol_list)
  42                 add_symbol(function_symbol_list, sym);
  43 }
  44
  45 static int match_idents(struct token *token, ...)
  46 {
  47         va_list args;
  48
  49         if (token_type(token) != TOKEN_IDENT)
  50                 return 0;
  51
  52         va_start(args, token);
  53         for (;;) {
  54                 struct ident * next = va_arg(args, struct ident *);
  55                 if (!next)
  56                         return 0;
  57                 if (token->ident == next)
  58                         return 1;
  59         }
  60 }
  61
  62
  63 struct statement *alloc_statement(struct position pos, int type)
  64 {
  65         struct statement *stmt = __alloc_statement(0);
  66         stmt->type = type;
  67         stmt->pos = pos;
  68         return stmt;
  69 }
  70
  71 static struct token *struct_declaration_list(struct token *token, struct symbol_list **list);
  72
  73 static struct symbol * indirect(struct position pos, struct ctype *ctype, int type)
  74 {
  75         struct symbol *sym = alloc_symbol(pos, type);
  76
  77         sym->ctype.base_type = ctype->base_type;
  78         sym->ctype.modifiers = ctype->modifiers & ~MOD_STORAGE;
  79
  80         ctype->base_type = sym;
  81         ctype->modifiers &= MOD_STORAGE;
  82         return sym;
  83 }
  84
  85 static struct symbol *lookup_or_create_symbol(enum namespace ns, enum type type, struct token *token)
  86 {
  87         struct symbol *sym = lookup_symbol(token->ident, ns);
  88         if (!sym) {
  89                 sym = alloc_symbol(token->pos, type);
  90                 bind_symbol(sym, token->ident, ns);
  91                 if (type == SYM_LABEL)
  92                         fn_local_symbol(sym);
  93         }
  94         return sym;
  95 }
  96
  97 /*
  98  * NOTE! NS_LABEL is not just a different namespace,
  99  * it also ends up using function scope instead of the
 100  * regular symbol scope.
 101  */
 102 struct symbol *label_symbol(struct token *token)
 103 {
 104         return lookup_or_create_symbol(NS_LABEL, SYM_LABEL, token);
 105 }
 106
 107 static struct token *struct_union_enum_specifier(enum type type,
 108         struct token *token, struct ctype *ctype,
 109         struct token *(*parse)(struct token *, struct symbol *))
 110 {
 111         struct symbol *sym;
 112         struct position *repos;
 113
 114         ctype->modifiers = 0;
 115         if (token_type(token) == TOKEN_IDENT) {
 116                 sym = lookup_symbol(token->ident, NS_STRUCT);
 117                 if (!sym ||
 118                     (sym->scope != block_scope &&
 119                      (match_op(token->next,';') || match_op(token->next,'{')))) {
 120                         // Either a new symbol, or else an out-of-scope
 121                         // symbol being redefined.
 122                         sym = alloc_symbol(token->pos, type);
 123                         bind_symbol(sym, token->ident, NS_STRUCT);
 124                 }
 125                 if (sym->type != type)
 126                         error_die(token->pos, "invalid tag applied to %s", show_typename (sym));
 127                 ctype->base_type = sym;
 128                 repos = &token->pos;
 129                 token = token->next;
 130                 if (match_op(token, '{')) {
 131                         // The following test is actually wrong for empty
 132                         // structs, but (1) they are not C99, (2) gcc does
 133                         // the same thing, and (3) it's easier.
 134                         if (sym->symbol_list)
 135                                 error_die(token->pos, "redefinition of %s", show_typename (sym));
 136                         sym->pos = *repos;
 137                         token = parse(token->next, sym);
 138                         token = expect(token, '}', "at end of struct-union-enum-specifier");
 139
 140                         // Mark the structure as needing re-examination
 141                         sym->examined = 0;
 142                 }
 143                 return token;
 144         }
 145
 146         // private struct/union/enum type
 147         if (!match_op(token, '{')) {
 148                 sparse_error(token->pos, "expected declaration");
 149                 ctype->base_type = &bad_ctype;
 150                 return token;
 151         }
 152
 153         sym = alloc_symbol(token->pos, type);
 154         token = parse(token->next, sym);
 155         ctype->base_type = sym;
 156         return expect(token, '}', "at end of specifier");
 157 }
 158
 159 static struct token *parse_struct_declaration(struct token *token, struct symbol *sym)
 160 {
 161         return struct_declaration_list(token, &sym->symbol_list);
 162 }
 163
 164 static struct token *struct_or_union_specifier(enum type type, struct token *token, struct ctype *ctype)
 165 {
 166         return struct_union_enum_specifier(type, token, ctype, parse_struct_declaration);
 167 }
 168
 169 typedef struct {
 170         int x;
 171         unsigned long long y;
 172 } Num;
 173
 174 static void upper_boundary(Num *n, Num *v)
 175 {
 176         if (n->x > v->x)
 177                 return;
 178         if (n->x < v->x) {
 179                 *n = *v;
 180                 return;
 181         }
 182         if (n->y < v->y)
 183                 n->y = v->y;
 184 }
 185
 186 static void lower_boundary(Num *n, Num *v)
 187 {
 188         if (n->x < v->x)
 189                 return;
 190         if (n->x > v->x) {
 191                 *n = *v;
 192                 return;
 193         }
 194         if (n->y > v->y)
 195                 n->y = v->y;
 196 }
 197
 198 static int type_is_ok(struct symbol *type, Num *upper, Num *lower)
 199 {
 200         int shift = type->bit_size;
 201         int is_unsigned = type->ctype.modifiers & MOD_UNSIGNED;
 202
 203         if (!is_unsigned)
 204                 shift--;
 205         if (upper->x == 0 && upper->y >> shift)
 206                 return 0;
 207         if (lower->x == 0 || (!is_unsigned && (~lower->y >> shift) == 0))
 208                 return 1;
 209         return 0;
 210 }
 211
 212 static struct symbol *bigger_enum_type(struct symbol *s1, struct symbol *s2)
 213 {
 214         if (s1->bit_size < s2->bit_size) {
 215                 s1 = s2;
 216         } else if (s1->bit_size == s2->bit_size) {
 217                 if (s2->ctype.modifiers & MOD_UNSIGNED)
 218                         s1 = s2;
 219         }
 220         if (s1->bit_size < bits_in_int)
 221                 return &int_ctype;
 222         return s1;
 223 }
 224
 225 static void cast_enum_list(struct symbol_list *list, struct symbol *base_type)
 226 {
 227         struct symbol *sym;
 228
 229         FOR_EACH_PTR(list, sym) {
 230                 struct expression *expr = sym->initializer;
 231                 struct symbol *ctype;
 232                 if (expr->type != EXPR_VALUE)
 233                         continue;
 234                 ctype = expr->ctype;
 235                 if (ctype->bit_size == base_type->bit_size)
 236                         continue;
 237                 cast_value(expr, base_type, expr, ctype);
 238         } END_FOR_EACH_PTR(sym);
 239 }
 240
 241 static struct token *parse_enum_declaration(struct token *token, struct symbol *parent)
 242 {
 243         unsigned long long lastval = 0;
 244         struct symbol *ctype = NULL, *base_type = NULL;
 245         Num upper = {-1, 0}, lower = {1, 0};
 246         struct symbol_list *entries = NULL;
 247
 248         parent->examined = 1;
 249         parent->ctype.base_type = &int_ctype;
 250         while (token_type(token) == TOKEN_IDENT) {
 251                 struct expression *expr = NULL;
 252                 struct token *next = token->next;
 253                 struct symbol *sym;
 254
 255                 sym = alloc_symbol(token->pos, SYM_NODE);
 256                 bind_symbol(sym, token->ident, NS_SYMBOL);
 257                 sym->ctype.modifiers &= ~MOD_ADDRESSABLE;
 258
 259                 if (match_op(next, '=')) {
 260                         next = constant_expression(next->next, &expr);
 261                         lastval = get_expression_value(expr);
 262                         ctype = &void_ctype;
 263                         if (expr && expr->ctype)
 264                                 ctype = expr->ctype;
 265                 } else if (!ctype) {
 266                         ctype = &int_ctype;
 267                 } else if (is_int_type(ctype)) {
 268                         lastval++;
 269                 } else {
 270                         error_die(token->pos, "can't increment the last enum member");
 271                 }
 272
 273                 if (!expr) {
 274                         expr = alloc_expression(token->pos, EXPR_VALUE);
 275                         expr->value = lastval;
 276                         expr->ctype = ctype;
 277                 }
 278
 279                 sym->initializer = expr;
 280                 sym->ctype.base_type = parent;
 281                 add_ptr_list(&entries, sym);
 282
 283                 if (base_type != &bad_ctype) {
 284                         if (ctype->type == SYM_NODE)
 285                                 ctype = ctype->ctype.base_type;
 286                         if (ctype->type == SYM_ENUM) {
 287                                 if (ctype == parent)
 288                                         ctype = base_type;
 289                                 else
 290                                         ctype = ctype->ctype.base_type;
 291                         }
 292                         /*
 293                          * base_type rules:
 294                          *  - if all enum's are of the same type, then
 295                          *    the base_type is that type (two first
 296                          *    cases)
 297                          *  - if enums are of different types, they
 298                          *    all have to be integer types, and the
 299                          *    base type is at least "int_ctype".
 300                          *  - otherwise the base_type is "bad_ctype".
 301                          */
 302                         if (!base_type) {
 303                                 base_type = ctype;
 304                         } else if (ctype == base_type) {
 305                                 /* nothing */
 306                         } else if (is_int_type(base_type) && is_int_type(ctype)) {
 307                                 base_type = bigger_enum_type(base_type, ctype);
 308                         } else
 309                                 base_type = &bad_ctype;
 310                         parent->ctype.base_type = base_type;
 311                 }
 312                 if (is_int_type(base_type)) {
 313                         Num v = {.y = lastval};
 314                         if (ctype->ctype.modifiers & MOD_UNSIGNED)
 315                                 v.x = 0;
 316                         else if ((long long)lastval >= 0)
 317                                 v.x = 0;
 318                         else
 319                                 v.x = -1;
 320                         upper_boundary(&upper, &v);
 321                         lower_boundary(&lower, &v);
 322                 }
 323                 token = next;
 324                 if (!match_op(token, ','))
 325                         break;
 326                 token = token->next;
 327         }
 328         if (!base_type) {
 329                 sparse_error(token->pos, "bad enum definition");
 330                 base_type = &bad_ctype;
 331         }
 332         else if (!is_int_type(base_type))
 333                 base_type = base_type;
 334         else if (type_is_ok(base_type, &upper, &lower))
 335                 base_type = base_type;
 336         else if (type_is_ok(&int_ctype, &upper, &lower))
 337                 base_type = &int_ctype;
 338         else if (type_is_ok(&uint_ctype, &upper, &lower))
 339                 base_type = &uint_ctype;
 340         else if (type_is_ok(&long_ctype, &upper, &lower))
 341                 base_type = &long_ctype;
 342         else if (type_is_ok(&ulong_ctype, &upper, &lower))
 343                 base_type = &ulong_ctype;
 344         else if (type_is_ok(&llong_ctype, &upper, &lower))
 345                 base_type = &llong_ctype;
 346         else if (type_is_ok(&ullong_ctype, &upper, &lower))
 347                 base_type = &ullong_ctype;
 348         else
 349                 base_type = &bad_ctype;
 350         parent->ctype.base_type = base_type;
 351         parent->ctype.modifiers |= (base_type->ctype.modifiers & MOD_UNSIGNED);
 352         parent->examined = 0;
 353
 354         cast_enum_list(entries, base_type);
 355         free_ptr_list(&entries);
 356
 357         return token;
 358 }
 359
 360 static struct token *enum_specifier(struct token *token, struct ctype *ctype)
 361 {
 362         struct token *ret = struct_union_enum_specifier(SYM_ENUM, token, ctype, parse_enum_declaration);
 363
 364         ctype = &ctype->base_type->ctype;
 365         if (!ctype->base_type)
 366                 ctype->base_type = &incomplete_ctype;
 367
 368         return ret;
 369 }
 370
 371 static struct token *typeof_specifier(struct token *token, struct ctype *ctype)
 372 {
 373         struct symbol *sym;
 374
 375         if (!match_op(token, '(')) {
 376                 sparse_error(token->pos, "expected '(' after typeof");
 377                 return token;
 378         }
 379         if (lookup_type(token->next)) {
 380                 token = typename(token->next, &sym);
 381                 *ctype = sym->ctype;
 382         } else {
 383                 struct symbol *typeof_sym = alloc_symbol(token->pos, SYM_TYPEOF);
 384                 token = parse_expression(token->next, &typeof_sym->initializer);
 385
 386                 ctype->modifiers = 0;
 387                 ctype->base_type = typeof_sym;
 388         }
 389         return expect(token, ')', "after typeof");
 390 }
 391
 392 static const char * handle_attribute(struct ctype *ctype, struct ident *attribute, struct expression *expr)
 393 {
 394         if (attribute == &packed_ident ||
 395             attribute == &__packed___ident) {
 396                 ctype->alignment = 1;
 397                 return NULL;
 398         }
 399         if (attribute == &aligned_ident ||
 400             attribute == &__aligned___ident) {
 401                 int alignment = max_alignment;
 402                 if (expr)
 403                         alignment = get_expression_value(expr);
 404                 ctype->alignment = alignment;
 405                 return NULL;
 406         }
 407         if (attribute == &nocast_ident) {
 408                 ctype->modifiers |= MOD_NOCAST;
 409                 return NULL;
 410         }
 411         if (attribute == &noderef_ident) {
 412                 ctype->modifiers |= MOD_NODEREF;
 413                 return NULL;
 414         }
 415         if (attribute == &safe_ident) {
 416                 ctype->modifiers |= MOD_SAFE;
 417                 return NULL;
 418         }
 419         if (attribute == &force_ident) {
 420                 ctype->modifiers |= MOD_FORCE;
 421                 return NULL;
 422         }
 423         if (attribute == &bitwise_ident ||
 424             attribute == &__bitwise___ident) {
 425                 if (Wbitwise)
 426                         ctype->modifiers |= MOD_BITWISE;
 427                 return NULL;
 428         }
 429         if (attribute == &address_space_ident) {
 430                 if (!expr)
 431                         return "expected address space number";
 432                 ctype->as = get_expression_value(expr);
 433                 return NULL;
 434         }
 435         if (attribute == &context_ident) {
 436                 if (expr && expr->type == EXPR_COMMA) {
 437                         struct context *context = alloc_context();
 438                         if(expr->left->type == EXPR_COMMA) {
 439                                 context->context = expr->left->left;
 440                                 context->in = get_expression_value(
 441                                         expr->left->right);
 442                         } else {
 443                                 context->context = NULL;
 444                                 context->in = get_expression_value(expr->left);
 445                         }
 446                         context->out = get_expression_value(expr->right);
 447                         add_ptr_list(&ctype->contexts, context);
 448                         return NULL;
 449                 }
 450                 return "expected context input/output values";
 451         }
 452         if (attribute == &mode_ident ||
 453             attribute == &__mode___ident) {
 454                 if (expr && expr->type == EXPR_SYMBOL) {
 455                         struct ident *ident = expr->symbol_name;
 456
 457                         /*
 458                          * Match against __QI__/__HI__/__SI__/__DI__
 459                          *
 460                          * FIXME! This is broken - we don't actually get
 461                          * the type information updated properly at this
 462                          * stage for some reason.
 463                          */
 464                         if (ident == &__QI___ident ||
 465                             ident == &QI_ident) {
 466                                 ctype->modifiers |= MOD_CHAR;
 467                                 return NULL;
 468                         }
 469                         if (ident == &__HI___ident ||
 470                             ident == &HI_ident) {
 471                                 ctype->modifiers |= MOD_SHORT;
 472                                 return NULL;
 473                         }
 474                         if (ident == &__SI___ident ||
 475                             ident == &SI_ident) {
 476                                 /* Nothing? */
 477                                 return NULL;
 478                         }
 479                         if (ident == &__DI___ident ||
 480                             ident == &DI_ident) {
 481                                 ctype->modifiers |= MOD_LONGLONG;
 482                                 return NULL;
 483                         }
 484                         if (ident == &__word___ident ||
 485                             ident == &word_ident) {
 486                                 ctype->modifiers |= MOD_LONG;
 487                                 return NULL;
 488                         }
 489                         return "unknown mode attribute";
 490                 }
 491                 return "expected attribute mode symbol";
 492         }
 493
 494         /* Throw away for now.. */
 495         if (attribute == &__transparent_union___ident) {
 496                 if (Wtransparent_union)
 497                     return "ignoring attribute __transparent_union__";
 498                 return NULL;
 499         }
 500         if (attribute == &nothrow_ident ||
 501             attribute == &__nothrow_ident ||
 502             attribute == &__nothrow___ident)
 503                 return NULL;
 504         if (attribute == &__malloc___ident)
 505                 return NULL;
 506         if (attribute == &nonnull_ident ||
 507             attribute == &__nonnull_ident ||
 508             attribute == &__nonnull___ident)
 509                 return NULL;
 510         if (attribute == &format_ident ||
 511             attribute == &__format___ident ||
 512             attribute == &__format_arg___ident)
 513                 return NULL;
 514         if (attribute == &section_ident ||
 515             attribute == &__section___ident)
 516                 return NULL;
 517         if (attribute == &unused_ident ||
 518             attribute == &__unused___ident)
 519                 return NULL;
 520         if (attribute == &const_ident ||
 521             attribute == &__const_ident ||
 522             attribute == &__const___ident)
 523                 return NULL;
 524         if (attribute == &noreturn_ident ||
 525             attribute == &__noreturn___ident)
 526                 return NULL;
 527         if (attribute == &no_instrument_function_ident ||
 528             attribute == &__no_instrument_function___ident)
 529                 return NULL;
 530         if (attribute == &sentinel_ident ||
 531             attribute == &__sentinel___ident)
 532                 return NULL;
 533         if (attribute == &regparm_ident)
 534                 return NULL;
 535         if (attribute == &weak_ident ||
 536             attribute == &__weak___ident)
 537                 return NULL;
 538         if (attribute == &alias_ident)
 539                 return NULL;
 540         if (attribute == &pure_ident ||
 541             attribute == &__pure___ident)
 542                 return NULL;
 543         if (attribute == &always_inline_ident)
 544                 return NULL;
 545         if (attribute == &syscall_linkage_ident)
 546                 return NULL;
 547         if (attribute == &visibility_ident)
 548                 return NULL;
 549         if (attribute == &deprecated_ident ||
 550             attribute == &__deprecated___ident)
 551                 return NULL;
 552         if (attribute == &noinline_ident)
 553                 return NULL;
 554         if (attribute == &__used___ident)
 555                 return NULL;
 556         if (attribute == &warn_unused_result_ident ||
 557             attribute == &__warn_unused_result___ident)
 558                 return NULL;
 559         if (attribute == &model_ident ||
 560             attribute == &__model___ident)
 561                 return NULL;
 562
 563         return "unknown attribute";
 564 }
 565
 566 static struct token *attribute_specifier(struct token *token, struct ctype *ctype)
 567 {
 568         ctype->modifiers = 0;
 569         token = expect(token, '(', "after attribute");
 570         token = expect(token, '(', "after attribute");
 571
 572         for (;;) {
 573                 const char *error_str;
 574                 struct ident *attribute_name;
 575                 struct expression *attribute_expr;
 576
 577                 if (eof_token(token))
 578                         break;
 579                 if (match_op(token, ';'))
 580                         break;
 581                 if (token_type(token) != TOKEN_IDENT)
 582                         break;
 583                 attribute_name = token->ident;
 584                 token = token->next;
 585                 attribute_expr = NULL;
 586                 if (match_op(token, '('))
 587                         token = parens_expression(token, &attribute_expr, "in attribute");
 588                 error_str = handle_attribute(ctype, attribute_name, attribute_expr);
 589                 if (error_str)
 590                         sparse_error(token->pos, "attribute '%s': %s", show_ident(attribute_name), error_str);
 591                 if (!match_op(token, ','))
 592                         break;
 593                 token = token->next;
 594         }
 595
 596         token = expect(token, ')', "after attribute");
 597         token = expect(token, ')', "after attribute");
 598         return token;
 599 }
 600
 601 struct symbol * ctype_integer(unsigned long spec)
 602 {
 603         static struct symbol *const integer_ctypes[][3] = {
 604                 { &llong_ctype, &sllong_ctype, &ullong_ctype },
 605                 { &long_ctype,  &slong_ctype,  &ulong_ctype  },
 606                 { &short_ctype, &sshort_ctype, &ushort_ctype },
 607                 { &char_ctype,  &schar_ctype,  &uchar_ctype  },
 608                 { &int_ctype,   &sint_ctype,   &uint_ctype   },
 609         };
 610         struct symbol *const (*ctype)[3];
 611         int sub;
 612
 613         ctype = integer_ctypes;
 614         if (!(spec & MOD_LONGLONG)) {
 615                 ctype++;
 616                 if (!(spec & MOD_LONG)) {
 617                         ctype++;
 618                         if (!(spec & MOD_SHORT)) {
 619                                 ctype++;
 620                                 if (!(spec & MOD_CHAR))
 621                                         ctype++;
 622                         }
 623                 }
 624         }
 625
 626         sub = ((spec & MOD_UNSIGNED)
 627                ? 2
 628                : ((spec & MOD_EXPLICITLY_SIGNED)
 629                   ? 1
 630                   : 0));
 631
 632         return ctype[0][sub];
 633 }
 634
 635 struct symbol * ctype_fp(unsigned long spec)
 636 {
 637         if (spec & MOD_LONGLONG)
 638                 return &ldouble_ctype;
 639         if (spec & MOD_LONG)
 640                 return &double_ctype;
 641         return &float_ctype;
 642 }
 643
 644 static void apply_ctype(struct position pos, struct ctype *thistype, struct ctype *ctype)
 645 {
 646         unsigned long mod = thistype->modifiers;
 647
 648         if (mod) {
 649                 unsigned long old = ctype->modifiers;
 650                 unsigned long extra = 0, dup, conflict;
 651
 652                 if (mod & old & MOD_LONG) {
 653                         extra = MOD_LONGLONG | MOD_LONG;
 654                         mod &= ~MOD_LONG;
 655                         old &= ~MOD_LONG;
 656                 }
 657                 dup = (mod & old) | (extra & old) | (extra & mod);
 658                 if (dup)
 659                         sparse_error(pos, "Just how %sdo you want this type to be?",
 660                                 modifier_string(dup));
 661
 662                 conflict = !(~mod & ~old & (MOD_LONG | MOD_SHORT));
 663                 if (conflict)
 664                         sparse_error(pos, "You cannot have both long and short modifiers.");
 665
 666                 conflict = !(~mod & ~old & (MOD_SIGNED | MOD_UNSIGNED));
 667                 if (conflict)
 668                         sparse_error(pos, "You cannot have both signed and unsigned modifiers.");
 669
 670                 // Only one storage modifier allowed, except that "inline" doesn't count.
 671                 conflict = (mod | old) & (MOD_STORAGE & ~MOD_INLINE);
 672                 conflict &= (conflict - 1);
 673                 if (conflict)
 674                         sparse_error(pos, "multiple storage classes");
 675
 676                 ctype->modifiers = old | mod | extra;
 677         }
 678
 679         /* Context */
 680         concat_ptr_list((struct ptr_list *)thistype->contexts,
 681                         (struct ptr_list **)&ctype->contexts);
 682
 683         /* Alignment */
 684         if (thistype->alignment & (thistype->alignment-1)) {
 685                 warning(pos, "I don't like non-power-of-2 alignments");
 686                 thistype->alignment = 0;
 687         }
 688         if (thistype->alignment > ctype->alignment)
 689                 ctype->alignment = thistype->alignment;
 690
 691         /* Address space */
 692         if (thistype->as)
 693                 ctype->as = thistype->as;
 694 }
 695
 696 static void check_modifiers(struct position *pos, struct symbol *s, unsigned long mod)
 697 {
 698         unsigned long banned, wrong;
 699         unsigned long this_mod = s->ctype.modifiers;
 700         const unsigned long BANNED_SIZE = MOD_LONG | MOD_LONGLONG | MOD_SHORT;
 701         const unsigned long BANNED_SIGN = MOD_SIGNED | MOD_UNSIGNED;
 702
 703         if (this_mod & (MOD_STRUCTOF | MOD_UNIONOF | MOD_ENUMOF))
 704                 banned = BANNED_SIZE | BANNED_SIGN;
 705         else if (this_mod & MOD_SPECIALBITS)
 706                 banned = 0;
 707         else if (s->ctype.base_type == &fp_type)
 708                 banned = BANNED_SIGN;
 709         else if (s->ctype.base_type == &int_type || !s->ctype.base_type || is_int_type (s))
 710                 banned = 0;
 711         else {
 712                 // label_type
 713                 // void_type
 714                 // bad_type
 715                 // vector_type <-- whatever that is
 716                 banned = BANNED_SIZE | BANNED_SIGN;
 717         }
 718
 719         wrong = mod & banned;
 720         if (wrong)
 721                 sparse_error(*pos, "modifier %sis invalid in this context",
 722                      modifier_string (wrong));
 723 }
 724
 725
 726 static struct token *declaration_specifiers(struct token *next, struct ctype *ctype, int qual)
 727 {
 728         struct token *token;
 729
 730         while ( (token = next) != NULL ) {
 731                 struct ctype thistype;
 732                 struct ident *ident;
 733                 struct symbol *s, *type;
 734                 unsigned long mod;
 735
 736                 next = token->next;
 737                 if (token_type(token) != TOKEN_IDENT)
 738                         break;
 739                 ident = token->ident;
 740
 741                 s = lookup_symbol(ident, NS_TYPEDEF);
 742                 if (!s)
 743                         break;
 744                 thistype = s->ctype;
 745                 mod = thistype.modifiers;
 746                 if (qual && (mod & ~(MOD_ATTRIBUTE | MOD_CONST | MOD_VOLATILE)))
 747                         break;
 748                 if (mod & MOD_SPECIALBITS) {
 749                         if (mod & MOD_STRUCTOF)
 750                                 next = struct_or_union_specifier(SYM_STRUCT, next, &thistype);
 751                         else if (mod & MOD_UNIONOF)
 752                                 next = struct_or_union_specifier(SYM_UNION, next, &thistype);
 753                         else if (mod & MOD_ENUMOF)
 754                                 next = enum_specifier(next, &thistype);
 755                         else if (mod & MOD_ATTRIBUTE)
 756                                 next = attribute_specifier(next, &thistype);
 757                         else if (mod & MOD_TYPEOF)
 758                                 next = typeof_specifier(next, &thistype);
 759                         mod = thistype.modifiers;
 760                 }
 761                 type = thistype.base_type;
 762                 if (type) {
 763                         if (qual)
 764                                 break;
 765                         if (ctype->base_type)
 766                                 break;
 767                         /* User types only mix with qualifiers */
 768                         if (mod & MOD_USERTYPE) {
 769                                 if (ctype->modifiers & MOD_SPECIFIER)
 770                                         break;
 771                         }
 772                         ctype->base_type = type;
 773                 }
 774
 775                 check_modifiers(&token->pos, s, ctype->modifiers);
 776                 apply_ctype(token->pos, &thistype, ctype);
 777         }
 778
 779         /* Turn the "virtual types" into real types with real sizes etc */
 780         if (!ctype->base_type) {
 781                 struct symbol *base = &incomplete_ctype;
 782
 783                 /*
 784                  * If we have modifiers, we'll default to an integer
 785                  * type, and "ctype_integer()" will turn this into
 786                  * a specific one.
 787                  */
 788                 if (ctype->modifiers & MOD_SPECIFIER)
 789                         base = &int_type;
 790                 ctype->base_type = base;
 791         }
 792         if (ctype->base_type == &int_type) {
 793                 ctype->base_type = ctype_integer(ctype->modifiers);
 794                 ctype->modifiers &= ~MOD_SPECIFIER;
 795         } else if (ctype->base_type == &fp_type) {
 796                 ctype->base_type = ctype_fp(ctype->modifiers);
 797                 ctype->modifiers &= ~MOD_SPECIFIER;
 798         }
 799         if (ctype->modifiers & MOD_BITWISE) {
 800                 struct symbol *type;
 801                 ctype->modifiers &= ~(MOD_BITWISE | MOD_SPECIFIER);
 802                 if (!is_int_type(ctype->base_type)) {
 803                         sparse_error(token->pos, "invalid modifier");
 804                         return token;
 805                 }
 806                 type = alloc_symbol(token->pos, SYM_BASETYPE);
 807                 *type = *ctype->base_type;
 808                 type->ctype.base_type = ctype->base_type;
 809                 type->type = SYM_RESTRICT;
 810                 type->ctype.modifiers &= ~MOD_SPECIFIER;
 811                 ctype->base_type = type;
 812                 create_fouled(type);
 813         }
 814         return token;
 815 }
 816
 817 static struct token *abstract_array_declarator(struct token *token, struct symbol *sym)
 818 {
 819         struct expression *expr = NULL;
 820
 821         token = parse_expression(token, &expr);
 822         sym->array_size = expr;
 823         return token;
 824 }
 825
 826 static struct token *parameter_type_list(struct token *, struct symbol *, struct ident **p);
 827 static struct token *declarator(struct token *token, struct symbol *sym, struct ident **p);
 828
 829 static struct token *handle_attributes(struct token *token, struct ctype *ctype)
 830 {
 831         for (;;) {
 832                 if (token_type(token) != TOKEN_IDENT)
 833                         break;
 834                 if (match_idents(token, &__attribute___ident, &__attribute_ident, NULL)) {
 835                         struct ctype thistype = { 0, };
 836                         token = attribute_specifier(token->next, &thistype);
 837                         apply_ctype(token->pos, &thistype, ctype);
 838                         continue;
 839                 }
 840                 if (match_idents(token, &asm_ident, &__asm_ident, &__asm___ident)) {
 841                         struct expression *expr;
 842                         token = expect(token->next, '(', "after asm");
 843                         token = parse_expression(token->next, &expr);
 844                         token = expect(token, ')', "after asm");
 845                         continue;
 846                 }
 847                 break;
 848         }
 849         return token;
 850 }
 851
 852 static struct token *direct_declarator(struct token *token, struct symbol *decl, struct ident **p)
 853 {
 854         struct ctype *ctype = &decl->ctype;
 855
 856         if (p && token_type(token) == TOKEN_IDENT) {
 857                 *p = token->ident;
 858                 token = token->next;
 859         }
 860
 861         for (;;) {
 862                 token = handle_attributes(token, ctype);
 863
 864                 if (token_type(token) != TOKEN_SPECIAL)
 865                         return token;
 866
 867                 /*
 868                  * This can be either a parameter list or a grouping.
 869                  * For the direct (non-abstract) case, we know if must be
 870                  * a parameter list if we already saw the identifier.
 871                  * For the abstract case, we know if must be a parameter
 872                  * list if it is empty or starts with a type.
 873                  */
 874                 if (token->special == '(') {
 875                         struct symbol *sym;
 876                         struct token *next = token->next;
 877                         int fn = (p && *p) || match_op(next, ')') || lookup_type(next);
 878
 879                         if (!fn) {
 880                                 struct symbol *base_type = ctype->base_type;
 881                                 token = declarator(next, decl, p);
 882                                 token = expect(token, ')', "in nested declarator");
 883                                 while (ctype->base_type != base_type)
 884                                         ctype = &ctype->base_type->ctype;
 885                                 p = NULL;
 886                                 continue;
 887                         }
 888
 889                         sym = indirect(token->pos, ctype, SYM_FN);
 890                         token = parameter_type_list(next, sym, p);
 891                         token = expect(token, ')', "in function declarator");
 892                         continue;
 893                 }
 894                 if (token->special == '[') {
 895                         struct symbol *array = indirect(token->pos, ctype, SYM_ARRAY);
 896                         token = abstract_array_declarator(token->next, array);
 897                         token = expect(token, ']', "in abstract_array_declarator");
 898                         ctype = &array->ctype;
 899                         continue;
 900                 }
 901                 break;
 902         }
 903         return token;
 904 }
 905
 906 static struct token *pointer(struct token *token, struct ctype *ctype)
 907 {
 908         unsigned long modifiers;
 909         struct symbol *base_type;
 910
 911         modifiers = ctype->modifiers & ~(MOD_TYPEDEF | MOD_ATTRIBUTE);
 912         base_type = ctype->base_type;
 913         ctype->modifiers = modifiers;
 914
 915         while (match_op(token,'*')) {
 916                 struct symbol *ptr = alloc_symbol(token->pos, SYM_PTR);
 917                 ptr->ctype.modifiers = modifiers & ~MOD_STORAGE;
 918                 ptr->ctype.as = ctype->as;
 919                 concat_ptr_list((struct ptr_list *)ctype->contexts,
 920                                 (struct ptr_list **)&ptr->ctype.contexts);
 921                 ptr->ctype.base_type = base_type;
 922
 923                 base_type = ptr;
 924                 ctype->modifiers = modifiers & MOD_STORAGE;
 925                 ctype->base_type = base_type;
 926                 ctype->as = 0;
 927                 free_ptr_list(&ctype->contexts);
 928
 929                 token = declaration_specifiers(token->next, ctype, 1);
 930                 modifiers = ctype->modifiers;
 931         }
 932         return token;
 933 }
 934
 935 static struct token *declarator(struct token *token, struct symbol *sym, struct ident **p)
 936 {
 937         token = pointer(token, &sym->ctype);
 938         return direct_declarator(token, sym, p);
 939 }
 940
 941 static struct token *handle_bitfield(struct token *token, struct symbol *decl)
 942 {
 943         struct ctype *ctype = &decl->ctype;
 944         struct expression *expr;
 945         struct symbol *bitfield;
 946         long long width;
 947
 948         if (!is_int_type(ctype->base_type)) {
 949                 sparse_error(token->pos, "invalid bitfield specifier for type %s.",
 950                         show_typename(ctype->base_type));
 951                 // Parse this to recover gracefully.
 952                 return conditional_expression(token->next, &expr);
 953         }
 954
 955         bitfield = indirect(token->pos, ctype, SYM_BITFIELD);
 956         token = conditional_expression(token->next, &expr);
 957         width = get_expression_value(expr);
 958         bitfield->bit_size = width;
 959
 960         if (width < 0 || width > INT_MAX) {
 961                 sparse_error(token->pos, "invalid bitfield width, %lld.", width);
 962                 width = -1;
 963         } else if (decl->ident && width == 0) {
 964                 sparse_error(token->pos, "invalid named zero-width bitfield `%s'",
 965                      show_ident(decl->ident));
 966                 width = -1;
 967         } else if (decl->ident) {
 968                 struct symbol *base_type = bitfield->ctype.base_type;
 969                 int is_signed = !(base_type->ctype.modifiers & MOD_UNSIGNED);
 970                 if (Wone_bit_signed_bitfield && width == 1 && is_signed) {
 971                         // Valid values are either {-1;0} or {0}, depending on integer
 972                         // representation.  The latter makes for very efficient code...
 973                         sparse_error(token->pos, "dubious one-bit signed bitfield");
 974                 }
 975                 if (Wdefault_bitfield_sign &&
 976                     base_type->type != SYM_ENUM &&
 977                     !(base_type->ctype.modifiers & MOD_EXPLICITLY_SIGNED) &&
 978                     is_signed) {
 979                         // The sign of bitfields is unspecified by default.
 980                         sparse_error(token->pos, "dubious bitfield without explicit `signed' or `unsigned'");
 981                 }
 982         }
 983         bitfield->bit_size = width;
 984         return token;
 985 }
 986
 987 static struct token *declaration_list(struct token *token, struct symbol_list **list)
 988 {
 989         struct ctype ctype = {0, };
 990
 991         token = declaration_specifiers(token, &ctype, 0);
 992         for (;;) {
 993                 struct ident *ident = NULL;
 994                 struct symbol *decl = alloc_symbol(token->pos, SYM_NODE);
 995                 decl->ctype = ctype;
 996                 token = declarator(token, decl, &ident);
 997                 decl->ident = ident;
 998                 if (match_op(token, ':')) {
 999                         token = handle_bitfield(token, decl);
1000                         token = handle_attributes(token, &decl->ctype);
1001                 }
1002                 add_symbol(list, decl);
1003                 if (!match_op(token, ','))
1004                         break;
1005                 token = token->next;
1006         }
1007         return token;
1008 }
1009
1010 static struct token *struct_declaration_list(struct token *token, struct symbol_list **list)
1011 {
1012         while (!match_op(token, '}')) {
1013                 token = declaration_list(token, list);
1014                 if (!match_op(token, ';')) {
1015                         sparse_error(token->pos, "expected ; at end of declaration");
1016                         break;
1017                 }
1018                 token = token->next;
1019         }
1020         return token;
1021 }
1022
1023 static struct token *parameter_declaration(struct token *token, struct symbol **tree)
1024 {
1025         struct ident *ident = NULL;
1026         struct symbol *sym;
1027         struct ctype ctype = { 0, };
1028
1029         token = declaration_specifiers(token, &ctype, 0);
1030         sym = alloc_symbol(token->pos, SYM_NODE);
1031         sym->ctype = ctype;
1032         *tree = sym;
1033         token = declarator(token, sym, &ident);
1034         sym->ident = ident;
1035         return token;
1036 }
1037
1038 struct token *typename(struct token *token, struct symbol **p)
1039 {
1040         struct symbol *sym = alloc_symbol(token->pos, SYM_NODE);
1041         *p = sym;
1042         token = declaration_specifiers(token, &sym->ctype, 0);
1043         return declarator(token, sym, NULL);
1044 }
1045
1046 static struct token *expression_statement(struct token *token, struct expression **tree)
1047 {
1048         token = parse_expression(token, tree);
1049         return expect(token, ';', "at end of statement");
1050 }
1051
1052 static struct token *parse_asm_operands(struct token *token, struct statement *stmt,
1053         struct expression_list **inout)
1054 {
1055         struct expression *expr;
1056
1057         /* Allow empty operands */
1058         if (match_op(token->next, ':') || match_op(token->next, ')'))
1059                 return token->next;
1060         do {
1061                 struct ident *ident = NULL;
1062                 if (match_op(token->next, '[') &&
1063                     token_type(token->next->next) == TOKEN_IDENT &&
1064                     match_op(token->next->next->next, ']')) {
1065                         ident = token->next->next->ident;
1066                         token = token->next->next->next;
1067                 }
1068                 add_expression(inout, (struct expression *)ident); /* UGGLEE!!! */
1069                 token = primary_expression(token->next, &expr);
1070                 add_expression(inout, expr);
1071                 token = parens_expression(token, &expr, "in asm parameter");
1072                 add_expression(inout, expr);
1073         } while (match_op(token, ','));
1074         return token;
1075 }
1076
1077 static struct token *parse_asm_clobbers(struct token *token, struct statement *stmt,
1078         struct expression_list **clobbers)
1079 {
1080         struct expression *expr;
1081
1082         do {
1083                 token = primary_expression(token->next, &expr);
1084                 add_expression(clobbers, expr);
1085         } while (match_op(token, ','));
1086         return token;
1087 }
1088
1089 static struct token *parse_asm(struct token *token, struct statement *stmt)
1090 {
1091         stmt->type = STMT_ASM;
1092         if (match_idents(token, &__volatile___ident, &__volatile_ident, &volatile_ident, NULL)) {
1093                 token = token->next;
1094         }
1095         token = expect(token, '(', "after asm");
1096         token = parse_expression(token, &stmt->asm_string);
1097         if (match_op(token, ':'))
1098                 token = parse_asm_operands(token, stmt, &stmt->asm_outputs);
1099         if (match_op(token, ':'))
1100                 token = parse_asm_operands(token, stmt, &stmt->asm_inputs);
1101         if (match_op(token, ':'))
1102                 token = parse_asm_clobbers(token, stmt, &stmt->asm_clobbers);
1103         token = expect(token, ')', "after asm");
1104         return expect(token, ';', "at end of asm-statement");
1105 }
1106
1107 /* Make a statement out of an expression */
1108 static struct statement *make_statement(struct expression *expr)
1109 {
1110         struct statement *stmt;
1111
1112         if (!expr)
1113                 return NULL;
1114         stmt = alloc_statement(expr->pos, STMT_EXPRESSION);
1115         stmt->expression = expr;
1116         return stmt;
1117 }
1118
1119 /*
1120  * All iterators have two symbols associated with them:
1121  * the "continue" and "break" symbols, which are targets
1122  * for continue and break statements respectively.
1123  *
1124  * They are in a special name-space, but they follow
1125  * all the normal visibility rules, so nested iterators
1126  * automatically work right.
1127  */
1128 static void start_iterator(struct statement *stmt)
1129 {
1130         struct symbol *cont, *brk;
1131
1132         start_symbol_scope();
1133         cont = alloc_symbol(stmt->pos, SYM_NODE);
1134         bind_symbol(cont, &continue_ident, NS_ITERATOR);
1135         brk = alloc_symbol(stmt->pos, SYM_NODE);
1136         bind_symbol(brk, &break_ident, NS_ITERATOR);
1137
1138         stmt->type = STMT_ITERATOR;
1139         stmt->iterator_break = brk;
1140         stmt->iterator_continue = cont;
1141         fn_local_symbol(brk);
1142         fn_local_symbol(cont);
1143 }
1144
1145 static void end_iterator(struct statement *stmt)
1146 {
1147         end_symbol_scope();
1148 }
1149
1150 static struct statement *start_function(struct symbol *sym)
1151 {
1152         struct symbol *ret;
1153         struct statement *stmt = alloc_statement(sym->pos, STMT_COMPOUND);
1154
1155         start_function_scope();
1156         ret = alloc_symbol(sym->pos, SYM_NODE);
1157         ret->ctype = sym->ctype.base_type->ctype;
1158         ret->ctype.modifiers &= ~(MOD_STORAGE | MOD_CONST | MOD_VOLATILE | MOD_INLINE | MOD_ADDRESSABLE | MOD_NOCAST | MOD_NODEREF | MOD_ACCESSED | MOD_TOPLEVEL);
1159         ret->ctype.modifiers |= (MOD_AUTO | MOD_REGISTER);
1160         bind_symbol(ret, &return_ident, NS_ITERATOR);
1161         stmt->ret = ret;
1162         fn_local_symbol(ret);
1163
1164         // Currently parsed symbol for __func__/__FUNCTION__/__PRETTY_FUNCTION__
1165         current_fn = sym;
1166
1167         return stmt;
1168 }
1169
1170 static void end_function(struct symbol *sym)
1171 {
1172         current_fn = NULL;
1173         end_function_scope();
1174 }
1175
1176 /*
1177  * A "switch()" statement, like an iterator, has a
1178  * the "break" symbol associated with it. It works
1179  * exactly like the iterator break - it's the target
1180  * for any break-statements in scope, and means that
1181  * "break" handling doesn't even need to know whether
1182  * it's breaking out of an iterator or a switch.
1183  *
1184  * In addition, the "case" symbol is a marker for the
1185  * case/default statements to find the switch statement
1186  * that they are associated with.
1187  */
1188 static void start_switch(struct statement *stmt)
1189 {
1190         struct symbol *brk, *switch_case;
1191
1192         start_symbol_scope();
1193         brk = alloc_symbol(stmt->pos, SYM_NODE);
1194         bind_symbol(brk, &break_ident, NS_ITERATOR);
1195
1196         switch_case = alloc_symbol(stmt->pos, SYM_NODE);
1197         bind_symbol(switch_case, &case_ident, NS_ITERATOR);
1198         switch_case->stmt = stmt;
1199
1200         stmt->type = STMT_SWITCH;
1201         stmt->switch_break = brk;
1202         stmt->switch_case = switch_case;
1203
1204         fn_local_symbol(brk);
1205         fn_local_symbol(switch_case);
1206 }
1207
1208 static void end_switch(struct statement *stmt)
1209 {
1210         if (!stmt->switch_case->symbol_list)
1211                 warning(stmt->pos, "switch with no cases");
1212         end_symbol_scope();
1213 }
1214
1215 static void add_case_statement(struct statement *stmt)
1216 {
1217         struct symbol *target = lookup_symbol(&case_ident, NS_ITERATOR);
1218         struct symbol *sym;
1219
1220         if (!target) {
1221                 sparse_error(stmt->pos, "not in switch scope");
1222                 stmt->type = STMT_NONE;
1223                 return;
1224         }
1225         sym = alloc_symbol(stmt->pos, SYM_NODE);
1226         add_symbol(&target->symbol_list, sym);
1227         sym->stmt = stmt;
1228         stmt->case_label = sym;
1229         fn_local_symbol(sym);
1230 }
1231
1232 static struct token *parse_return_statement(struct token *token, struct statement *stmt)
1233 {
1234         struct symbol *target = lookup_symbol(&return_ident, NS_ITERATOR);
1235
1236         if (!target)
1237                 error_die(token->pos, "internal error: return without a function target");
1238         stmt->type = STMT_RETURN;
1239         stmt->ret_target = target;
1240         return expression_statement(token->next, &stmt->ret_value);
1241 }
1242
1243 static struct token *parse_for_statement(struct token *token, struct statement *stmt)
1244 {
1245         struct symbol_list *syms;
1246         struct expression *e1, *e2, *e3;
1247         struct statement *iterator;
1248
1249         start_iterator(stmt);
1250         token = expect(token->next, '(', "after 'for'");
1251
1252         syms = NULL;
1253         e1 = NULL;
1254         /* C99 variable declaration? */
1255         if (lookup_type(token)) {
1256                 token = external_declaration(token, &syms);
1257         } else {
1258                 token = parse_expression(token, &e1);
1259                 token = expect(token, ';', "in 'for'");
1260         }
1261         token = parse_expression(token, &e2);
1262         token = expect(token, ';', "in 'for'");
1263         token = parse_expression(token, &e3);
1264         token = expect(token, ')', "in 'for'");
1265         token = statement(token, &iterator);
1266
1267         stmt->iterator_syms = syms;
1268         stmt->iterator_pre_statement = make_statement(e1);
1269         stmt->iterator_pre_condition = e2;
1270         stmt->iterator_post_statement = make_statement(e3);
1271         stmt->iterator_post_condition = NULL;
1272         stmt->iterator_statement = iterator;
1273         end_iterator(stmt);
1274
1275         return token;
1276 }
1277
1278 static struct token *parse_while_statement(struct token *token, struct statement *stmt)
1279 {
1280         struct expression *expr;
1281         struct statement *iterator;
1282
1283         start_iterator(stmt);
1284         token = parens_expression(token->next, &expr, "after 'while'");
1285         token = statement(token, &iterator);
1286
1287         stmt->iterator_pre_condition = expr;
1288         stmt->iterator_post_condition = NULL;
1289         stmt->iterator_statement = iterator;
1290         end_iterator(stmt);
1291
1292         return token;
1293 }
1294
1295 static struct token *parse_do_statement(struct token *token, struct statement *stmt)
1296 {
1297         struct expression *expr;
1298         struct statement *iterator;
1299
1300         start_iterator(stmt);
1301         token = statement(token->next, &iterator);
1302         if (token_type(token) == TOKEN_IDENT && token->ident == &while_ident)
1303                 token = token->next;
1304         else
1305                 sparse_error(token->pos, "expected 'while' after 'do'");
1306         token = parens_expression(token, &expr, "after 'do-while'");
1307
1308         stmt->iterator_post_condition = expr;
1309         stmt->iterator_statement = iterator;
1310         end_iterator(stmt);
1311
1312         if (iterator && iterator->type != STMT_COMPOUND && Wdo_while)
1313                 warning(iterator->pos, "do-while statement is not a compound statement");
1314
1315         return expect(token, ';', "after statement");
1316 }
1317
1318 static struct token *statement(struct token *token, struct statement **tree)
1319 {
1320         struct statement *stmt = alloc_statement(token->pos, STMT_NONE);
1321
1322         *tree = stmt;
1323         if (token_type(token) == TOKEN_IDENT) {
1324                 if (token->ident == &if_ident) {
1325                         stmt->type = STMT_IF;
1326                         token = parens_expression(token->next, &stmt->if_conditional, "after if");
1327                         token = statement(token, &stmt->if_true);
1328                         if (token_type(token) != TOKEN_IDENT)
1329                                 return token;
1330                         if (token->ident != &else_ident)
1331                                 return token;
1332                         return statement(token->next, &stmt->if_false);
1333                 }
1334
1335                 if (token->ident == &return_ident)
1336                         return parse_return_statement(token, stmt);
1337
1338                 if (token->ident == &break_ident || token->ident == &continue_ident) {
1339                         struct symbol *target = lookup_symbol(token->ident, NS_ITERATOR);
1340                         stmt->type = STMT_GOTO;
1341                         stmt->goto_label = target;
1342                         if (!target)
1343                                 sparse_error(stmt->pos, "break/continue not in iterator scope");
1344                         return expect(token->next, ';', "at end of statement");
1345                 }
1346                 if (token->ident == &default_ident) {
1347                         token = token->next;
1348                         goto default_statement;
1349                 }
1350                 if (token->ident == &case_ident) {
1351                         token = parse_expression(token->next, &stmt->case_expression);
1352                         if (match_op(token, SPECIAL_ELLIPSIS))
1353                                 token = parse_expression(token->next, &stmt->case_to);
1354 default_statement:
1355                         stmt->type = STMT_CASE;
1356                         token = expect(token, ':', "after default/case");
1357                         add_case_statement(stmt);
1358                         return statement(token, &stmt->case_statement);
1359                 }
1360                 if (token->ident == &switch_ident) {
1361                         stmt->type = STMT_SWITCH;
1362                         start_switch(stmt);
1363                         token = parens_expression(token->next, &stmt->switch_expression, "after 'switch'");
1364                         token = statement(token, &stmt->switch_statement);
1365                         end_switch(stmt);
1366                         return token;
1367                 }
1368                 if (token->ident == &for_ident)
1369                         return parse_for_statement(token, stmt);
1370
1371                 if (token->ident == &while_ident)
1372                         return parse_while_statement(token, stmt);
1373
1374                 if (token->ident == &do_ident)
1375                         return parse_do_statement(token, stmt);
1376
1377                 if (token->ident == &goto_ident) {
1378                         stmt->type = STMT_GOTO;
1379                         token = token->next;
1380                         if (match_op(token, '*')) {
1381                                 token = parse_expression(token->next, &stmt->goto_expression);
1382                                 add_statement(&function_computed_goto_list, stmt);
1383                         } else if (token_type(token) == TOKEN_IDENT) {
1384                                 stmt->goto_label = label_symbol(token);
1385                                 token = token->next;
1386                         } else {
1387                                 sparse_error(token->pos, "Expected identifier or goto expression");
1388                         }
1389                         return expect(token, ';', "at end of statement");
1390                 }
1391                 if (match_idents(token, &asm_ident, &__asm___ident, &__asm_ident, NULL)) {
1392                         return parse_asm(token->next, stmt);
1393                 }
1394                 if (token->ident == &__context___ident) {
1395                         stmt->type = STMT_CONTEXT;
1396                         token = parse_expression(token->next, &stmt->expression);
1397                         if(stmt->expression->type == EXPR_PREOP
1398                            && stmt->expression->op == '('
1399                            && stmt->expression->unop->type == EXPR_COMMA) {
1400                                 struct expression *expr;
1401                                 expr = stmt->expression->unop;
1402                                 stmt->context = expr->left;
1403                                 stmt->expression = expr->right;
1404                         }
1405                         return expect(token, ';', "at end of statement");
1406                 }
1407                 if (token->ident == &__range___ident) {
1408                         stmt->type = STMT_RANGE;
1409                         token = assignment_expression(token->next, &stmt->range_expression);
1410                         token = expect(token, ',', "after range expression");
1411                         token = assignment_expression(token, &stmt->range_low);
1412                         token = expect(token, ',', "after low range");
1413                         token = assignment_expression(token, &stmt->range_high);
1414                         return expect(token, ';', "after range statement");
1415                 }
1416                 if (match_op(token->next, ':')) {
1417                         stmt->type = STMT_LABEL;
1418                         stmt->label_identifier = label_symbol(token);
1419                         return statement(token->next->next, &stmt->label_statement);
1420                 }
1421         }
1422
1423         if (match_op(token, '{')) {
1424                 stmt->type = STMT_COMPOUND;
1425                 start_symbol_scope();
1426                 token = compound_statement(token->next, stmt);
1427                 end_symbol_scope();
1428
1429                 return expect(token, '}', "at end of compound statement");
1430         }
1431
1432         stmt->type = STMT_EXPRESSION;
1433         return expression_statement(token, &stmt->expression);
1434 }
1435
1436 static struct token * statement_list(struct token *token, struct statement_list **list)
1437 {
1438         int seen_statement = 0;
1439         for (;;) {
1440                 struct statement * stmt;
1441                 if (eof_token(token))
1442                         break;
1443                 if (match_op(token, '}'))
1444                         break;
1445                 if (lookup_type(token)) {
1446                         if (seen_statement) {
1447                                 warning(token->pos, "mixing declarations and code");
1448                                 seen_statement = 0;
1449                         }
1450                         stmt = alloc_statement(token->pos, STMT_DECLARATION);
1451                         token = external_declaration(token, &stmt->declaration);
1452                 } else {
1453                         seen_statement = warn_on_mixed;
1454                         token = statement(token, &stmt);
1455                 }
1456                 add_statement(list, stmt);
1457         }
1458         return token;
1459 }
1460
1461 static struct token *parameter_type_list(struct token *token, struct symbol *fn, struct ident **p)
1462 {
1463         struct symbol_list **list = &fn->arguments;
1464
1465         if (match_op(token, ')')) {
1466                 // No warning for "void oink ();"
1467                 // Bug or feature: warns for "void oink () __attribute__ ((noreturn));"
1468                 if (p && !match_op(token->next, ';'))
1469                         warning(token->pos, "non-ANSI function declaration of function '%s'", show_ident(*p));
1470                 return token;
1471         }
1472
1473         for (;;) {
1474                 struct symbol *sym;
1475
1476                 if (match_op(token, SPECIAL_ELLIPSIS)) {
1477                         if (!*list)
1478                                 warning(token->pos, "variadic functions must have one named argument");
1479                         fn->variadic = 1;
1480                         token = token->next;
1481                         break;
1482                 }
1483
1484                 sym = alloc_symbol(token->pos, SYM_NODE);
1485                 token = parameter_declaration(token, &sym);
1486                 if (sym->ctype.base_type == &void_ctype) {
1487                         /* Special case: (void) */
1488                         if (!*list && !sym->ident)
1489                                 break;
1490                         warning(token->pos, "void parameter");
1491                 }
1492                 add_symbol(list, sym);
1493                 if (!match_op(token, ','))
1494                         break;
1495                 token = token->next;
1496
1497         }
1498         return token;
1499 }
1500
1501 struct token *compound_statement(struct token *token, struct statement *stmt)
1502 {
1503         token = statement_list(token, &stmt->stmts);
1504         return token;
1505 }
1506
1507 static struct expression *identifier_expression(struct token *token)
1508 {
1509         struct expression *expr = alloc_expression(token->pos, EXPR_IDENTIFIER);
1510         expr->expr_ident = token->ident;
1511         return expr;
1512 }
1513
1514 static struct expression *index_expression(struct expression *from, struct expression *to)
1515 {
1516         int idx_from, idx_to;
1517         struct expression *expr = alloc_expression(from->pos, EXPR_INDEX);
1518
1519         idx_from = get_expression_value(from);
1520         idx_to = idx_from;
1521         if (to) {
1522                 idx_to = get_expression_value(to);
1523                 if (idx_to < idx_from || idx_from < 0)
1524                         warning(from->pos, "nonsense array initializer index range");
1525         }
1526         expr->idx_from = idx_from;
1527         expr->idx_to = idx_to;
1528         return expr;
1529 }
1530
1531 static struct token *single_initializer(struct expression **ep, struct token *token)
1532 {
1533         int expect_equal = 0;
1534         struct token *next = token->next;
1535         struct expression **tail = ep;
1536         int nested;
1537
1538         *ep = NULL;
1539
1540         if ((token_type(token) == TOKEN_IDENT) && match_op(next, ':')) {
1541                 struct expression *expr = identifier_expression(token);
1542                 warning(token->pos, "obsolete struct initializer, use C99 syntax");
1543                 token = initializer(&expr->ident_expression, next->next);
1544                 if (expr->ident_expression)
1545                         *ep = expr;
1546                 return token;
1547         }
1548
1549         for (tail = ep, nested = 0; ; nested++, next = token->next) {
1550                 if (match_op(token, '.') && (token_type(next) == TOKEN_IDENT)) {
1551                         struct expression *expr = identifier_expression(next);
1552                         *tail = expr;
1553                         tail = &expr->ident_expression;
1554                         expect_equal = 1;
1555                         token = next->next;
1556                 } else if (match_op(token, '[')) {
1557                         struct expression *from = NULL, *to = NULL, *expr;
1558                         token = constant_expression(token->next, &from);
1559                         if (!from) {
1560                                 sparse_error(token->pos, "Expected constant expression");
1561                                 break;
1562                         }
1563                         if (match_op(token, SPECIAL_ELLIPSIS))
1564                                 token = constant_expression(token->next, &to);
1565                         expr = index_expression(from, to);
1566                         *tail = expr;
1567                         tail = &expr->idx_expression;
1568                         token = expect(token, ']', "at end of initializer index");
1569                         if (nested)
1570                                 expect_equal = 1;
1571                 } else {
1572                         break;
1573                 }
1574         }
1575         if (nested && !expect_equal) {
1576                 if (!match_op(token, '='))
1577                         warning(token->pos, "obsolete array initializer, use C99 syntax");
1578                 else
1579                         expect_equal = 1;
1580         }
1581         if (expect_equal)
1582                 token = expect(token, '=', "at end of initializer index");
1583
1584         token = initializer(tail, token);
1585         if (!*tail)
1586                 *ep = NULL;
1587         return token;
1588 }
1589
1590 static struct token *initializer_list(struct expression_list **list, struct token *token)
1591 {
1592         struct expression *expr;
1593
1594         for (;;) {
1595                 token = single_initializer(&expr, token);
1596                 if (!expr)
1597                         break;
1598                 add_expression(list, expr);
1599                 if (!match_op(token, ','))
1600                         break;
1601                 token = token->next;
1602         }
1603         return token;
1604 }
1605
1606 struct token *initializer(struct expression **tree, struct token *token)
1607 {
1608         if (match_op(token, '{')) {
1609                 struct expression *expr = alloc_expression(token->pos, EXPR_INITIALIZER);
1610                 *tree = expr;
1611                 token = initializer_list(&expr->expr_list, token->next);
1612                 return expect(token, '}', "at end of initializer");
1613         }
1614         return assignment_expression(token, tree);
1615 }
1616
1617 static void declare_argument(struct symbol *sym, struct symbol *fn)
1618 {
1619         if (!sym->ident) {
1620                 sparse_error(sym->pos, "no identifier for function argument");
1621                 return;
1622         }
1623         bind_symbol(sym, sym->ident, NS_SYMBOL);
1624 }
1625
1626 static struct token *parse_function_body(struct token *token, struct symbol *decl,
1627         struct symbol_list **list)
1628 {
1629         struct symbol_list **old_symbol_list;
1630         struct symbol *base_type = decl->ctype.base_type;
1631         struct statement *stmt, **p;
1632         struct symbol *arg;
1633
1634         old_symbol_list = function_symbol_list;
1635         if (decl->ctype.modifiers & MOD_INLINE) {
1636                 function_symbol_list = &decl->inline_symbol_list;
1637                 p = &base_type->inline_stmt;
1638         } else {
1639                 function_symbol_list = &decl->symbol_list;
1640                 p = &base_type->stmt;
1641         }
1642         function_computed_target_list = NULL;
1643         function_computed_goto_list = NULL;
1644
1645         if (decl->ctype.modifiers & MOD_EXTERN) {
1646                 if (!(decl->ctype.modifiers & MOD_INLINE))
1647                         warning(decl->pos, "function '%s' with external linkage has definition", show_ident(decl->ident));
1648         }
1649         if (!(decl->ctype.modifiers & MOD_STATIC))
1650                 decl->ctype.modifiers |= MOD_EXTERN;
1651
1652         stmt = start_function(decl);
1653
1654         *p = stmt;
1655         FOR_EACH_PTR (base_type->arguments, arg) {
1656                 declare_argument(arg, base_type);
1657         } END_FOR_EACH_PTR(arg);
1658
1659         token = compound_statement(token->next, stmt);
1660
1661         end_function(decl);
1662         if (!(decl->ctype.modifiers & MOD_INLINE))
1663                 add_symbol(list, decl);
1664         check_declaration(decl);
1665         function_symbol_list = old_symbol_list;
1666         if (function_computed_goto_list) {
1667                 if (!function_computed_target_list)
1668                         warning(decl->pos, "function '%s' has computed goto but no targets?", show_ident(decl->ident));
1669                 else {
1670                         struct statement *stmt;
1671                         FOR_EACH_PTR(function_computed_goto_list, stmt) {
1672                                 stmt->target_list = function_computed_target_list;
1673                         } END_FOR_EACH_PTR(stmt);
1674                 }
1675         }
1676         return expect(token, '}', "at end of function");
1677 }
1678
1679 static void promote_k_r_types(struct symbol *arg)
1680 {
1681         struct symbol *base = arg->ctype.base_type;
1682         if (base && base->ctype.base_type == &int_type && (base->ctype.modifiers & (MOD_CHAR | MOD_SHORT))) {
1683                 arg->ctype.base_type = &int_ctype;
1684         }
1685 }
1686
1687 static void apply_k_r_types(struct symbol_list *argtypes, struct symbol *fn)
1688 {
1689         struct symbol_list *real_args = fn->ctype.base_type->arguments;
1690         struct symbol *arg;
1691
1692         FOR_EACH_PTR(real_args, arg) {
1693                 struct symbol *type;
1694
1695                 /* This is quadratic in the number of arguments. We _really_ don't care */
1696                 FOR_EACH_PTR(argtypes, type) {
1697                         if (type->ident == arg->ident)
1698                                 goto match;
1699                 } END_FOR_EACH_PTR(type);
1700                 sparse_error(arg->pos, "missing type declaration for parameter '%s'", show_ident(arg->ident));
1701                 continue;
1702 match:
1703                 type->used = 1;
1704                 /* "char" and "short" promote to "int" */
1705                 promote_k_r_types(type);
1706
1707                 arg->ctype = type->ctype;
1708         } END_FOR_EACH_PTR(arg);
1709
1710         FOR_EACH_PTR(argtypes, arg) {
1711                 if (!arg->used)
1712                         warning(arg->pos, "nonsensical parameter declaration '%s'", show_ident(arg->ident));
1713         } END_FOR_EACH_PTR(arg);
1714
1715 }
1716
1717 static struct token *parse_k_r_arguments(struct token *token, struct symbol *decl,
1718         struct symbol_list **list)
1719 {
1720         struct symbol_list *args = NULL;
1721
1722         warning(token->pos, "non-ANSI definition of function '%s'", show_ident(decl->ident));
1723         do {
1724                 token = declaration_list(token, &args);
1725                 if (!match_op(token, ';')) {
1726                         sparse_error(token->pos, "expected ';' at end of parameter declaration");
1727                         break;
1728                 }
1729                 token = token->next;
1730         } while (lookup_type(token));
1731
1732         apply_k_r_types(args, decl);
1733
1734         if (!match_op(token, '{')) {
1735                 sparse_error(token->pos, "expected function body");
1736                 return token;
1737         }
1738         return parse_function_body(token, decl, list);
1739 }
1740
1741
1742 struct token *external_declaration(struct token *token, struct symbol_list **list)
1743 {
1744         struct ident *ident = NULL;
1745         struct symbol *decl;
1746         struct ctype ctype = { 0, };
1747         struct symbol *base_type;
1748         int is_typedef;
1749
1750         /* Top-level inline asm? */
1751         if (match_idents(token, &asm_ident, &__asm___ident, &__asm_ident, NULL)) {
1752                 struct symbol *anon = alloc_symbol(token->pos, SYM_NODE);
1753                 struct symbol *fn = alloc_symbol(token->pos, SYM_FN);
1754                 struct statement *stmt;
1755
1756                 anon->ctype.base_type = fn;
1757                 stmt = alloc_statement(token->pos, STMT_NONE);
1758                 fn->stmt = stmt;
1759
1760                 token = parse_asm(token->next, stmt);
1761
1762                 add_symbol(list, anon);
1763                 return token;
1764         }
1765
1766         /* Parse declaration-specifiers, if any */
1767         token = declaration_specifiers(token, &ctype, 0);
1768         decl = alloc_symbol(token->pos, SYM_NODE);
1769         decl->ctype = ctype;
1770         token = declarator(token, decl, &ident);
1771
1772         /* Just a type declaration? */
1773         if (!ident)
1774                 return expect(token, ';', "end of type declaration");
1775
1776         /* type define declaration? */
1777         is_typedef = (ctype.modifiers & MOD_TYPEDEF) != 0;
1778
1779         /* Typedef's don't have meaningful storage */
1780         if (is_typedef) {
1781                 ctype.modifiers &= ~MOD_STORAGE;
1782                 decl->ctype.modifiers &= ~MOD_STORAGE;
1783                 decl->ctype.modifiers |= MOD_USERTYPE;
1784         }
1785
1786         bind_symbol(decl, ident, is_typedef ? NS_TYPEDEF: NS_SYMBOL);
1787
1788         base_type = decl->ctype.base_type;
1789
1790         if (is_typedef) {
1791                 if (base_type && !base_type->ident)
1792                         base_type->ident = ident;
1793         } else if (base_type && base_type->type == SYM_FN) {
1794                 /* K&R argument declaration? */
1795                 if (lookup_type(token))
1796                         return parse_k_r_arguments(token, decl, list);
1797                 if (match_op(token, '{'))
1798                         return parse_function_body(token, decl, list);
1799
1800                 if (!(decl->ctype.modifiers & MOD_STATIC))
1801                         decl->ctype.modifiers |= MOD_EXTERN;
1802         } else if (base_type == &void_ctype && !(decl->ctype.modifiers & MOD_EXTERN)) {
1803                 sparse_error(token->pos, "void declaration");
1804         }
1805
1806         for (;;) {
1807                 if (!is_typedef && match_op(token, '=')) {
1808                         if (decl->ctype.modifiers & MOD_EXTERN) {
1809                                 warning(decl->pos, "symbol with external linkage has initializer");
1810                                 decl->ctype.modifiers &= ~MOD_EXTERN;
1811                         }
1812                         token = initializer(&decl->initializer, token->next);
1813                 }
1814                 if (!is_typedef) {
1815                         if (!(decl->ctype.modifiers & (MOD_EXTERN | MOD_INLINE))) {
1816                                 add_symbol(list, decl);
1817                                 fn_local_symbol(decl);
1818                         }
1819                 }
1820                 check_declaration(decl);
1821
1822                 if (!match_op(token, ','))
1823                         break;
1824
1825                 token = token->next;
1826                 ident = NULL;
1827                 decl = alloc_symbol(token->pos, SYM_NODE);
1828                 decl->ctype = ctype;
1829                 token = declaration_specifiers(token, &decl->ctype, 1);
1830                 token = declarator(token, decl, &ident);
1831                 if (!ident) {
1832                         sparse_error(token->pos, "expected identifier name in type definition");
1833                         return token;
1834                 }
1835
1836                 bind_symbol(decl, ident, is_typedef ? NS_TYPEDEF: NS_SYMBOL);
1837
1838                 /* Function declarations are automatically extern unless specifically static */
1839                 base_type = decl->ctype.base_type;
1840                 if (!is_typedef && base_type && base_type->type == SYM_FN) {
1841                         if (!(decl->ctype.modifiers & MOD_STATIC))
1842                                 decl->ctype.modifiers |= MOD_EXTERN;
1843                 }
1844         }
1845         return expect(token, ';', "at end of declaration");
1846 }