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             attribute == &__alias___ident)
 540                 return NULL;
 541         if (attribute == &pure_ident ||
 542             attribute == &__pure___ident)
 543                 return NULL;
 544         if (attribute == &always_inline_ident)
 545                 return NULL;
 546         if (attribute == &syscall_linkage_ident)
 547                 return NULL;
 548         if (attribute == &visibility_ident ||
 549             attribute == &__visibility___ident)
 550                 return NULL;
 551         if (attribute == &deprecated_ident ||
 552             attribute == &__deprecated___ident)
 553                 return NULL;
 554         if (attribute == &noinline_ident)
 555                 return NULL;
 556         if (attribute == &__used___ident)
 557                 return NULL;
 558         if (attribute == &warn_unused_result_ident ||
 559             attribute == &__warn_unused_result___ident)
 560                 return NULL;
 561         if (attribute == &model_ident ||
 562             attribute == &__model___ident)
 563                 return NULL;
 564
 565         return "unknown attribute";
 566 }
 567
 568 static struct token *attribute_specifier(struct token *token, struct ctype *ctype)
 569 {
 570         ctype->modifiers = 0;
 571         token = expect(token, '(', "after attribute");
 572         token = expect(token, '(', "after attribute");
 573
 574         for (;;) {
 575                 const char *error_str;
 576                 struct ident *attribute_name;
 577                 struct expression *attribute_expr;
 578
 579                 if (eof_token(token))
 580                         break;
 581                 if (match_op(token, ';'))
 582                         break;
 583                 if (token_type(token) != TOKEN_IDENT)
 584                         break;
 585                 attribute_name = token->ident;
 586                 token = token->next;
 587                 attribute_expr = NULL;
 588                 if (match_op(token, '('))
 589                         token = parens_expression(token, &attribute_expr, "in attribute");
 590                 error_str = handle_attribute(ctype, attribute_name, attribute_expr);
 591                 if (error_str)
 592                         sparse_error(token->pos, "attribute '%s': %s", show_ident(attribute_name), error_str);
 593                 if (!match_op(token, ','))
 594                         break;
 595                 token = token->next;
 596         }
 597
 598         token = expect(token, ')', "after attribute");
 599         token = expect(token, ')', "after attribute");
 600         return token;
 601 }
 602
 603 struct symbol * ctype_integer(unsigned long spec)
 604 {
 605         static struct symbol *const integer_ctypes[][3] = {
 606                 { &llong_ctype, &sllong_ctype, &ullong_ctype },
 607                 { &long_ctype,  &slong_ctype,  &ulong_ctype  },
 608                 { &short_ctype, &sshort_ctype, &ushort_ctype },
 609                 { &char_ctype,  &schar_ctype,  &uchar_ctype  },
 610                 { &int_ctype,   &sint_ctype,   &uint_ctype   },
 611         };
 612         struct symbol *const (*ctype)[3];
 613         int sub;
 614
 615         ctype = integer_ctypes;
 616         if (!(spec & MOD_LONGLONG)) {
 617                 ctype++;
 618                 if (!(spec & MOD_LONG)) {
 619                         ctype++;
 620                         if (!(spec & MOD_SHORT)) {
 621                                 ctype++;
 622                                 if (!(spec & MOD_CHAR))
 623                                         ctype++;
 624                         }
 625                 }
 626         }
 627
 628         sub = ((spec & MOD_UNSIGNED)
 629                ? 2
 630                : ((spec & MOD_EXPLICITLY_SIGNED)
 631                   ? 1
 632                   : 0));
 633
 634         return ctype[0][sub];
 635 }
 636
 637 struct symbol * ctype_fp(unsigned long spec)
 638 {
 639         if (spec & MOD_LONGLONG)
 640                 return &ldouble_ctype;
 641         if (spec & MOD_LONG)
 642                 return &double_ctype;
 643         return &float_ctype;
 644 }
 645
 646 static void apply_ctype(struct position pos, struct ctype *thistype, struct ctype *ctype)
 647 {
 648         unsigned long mod = thistype->modifiers;
 649
 650         if (mod) {
 651                 unsigned long old = ctype->modifiers;
 652                 unsigned long extra = 0, dup, conflict;
 653
 654                 if (mod & old & MOD_LONG) {
 655                         extra = MOD_LONGLONG | MOD_LONG;
 656                         mod &= ~MOD_LONG;
 657                         old &= ~MOD_LONG;
 658                 }
 659                 dup = (mod & old) | (extra & old) | (extra & mod);
 660                 if (dup)
 661                         sparse_error(pos, "Just how %sdo you want this type to be?",
 662                                 modifier_string(dup));
 663
 664                 conflict = !(~mod & ~old & (MOD_LONG | MOD_SHORT));
 665                 if (conflict)
 666                         sparse_error(pos, "You cannot have both long and short modifiers.");
 667
 668                 conflict = !(~mod & ~old & (MOD_SIGNED | MOD_UNSIGNED));
 669                 if (conflict)
 670                         sparse_error(pos, "You cannot have both signed and unsigned modifiers.");
 671
 672                 // Only one storage modifier allowed, except that "inline" doesn't count.
 673                 conflict = (mod | old) & (MOD_STORAGE & ~MOD_INLINE);
 674                 conflict &= (conflict - 1);
 675                 if (conflict)
 676                         sparse_error(pos, "multiple storage classes");
 677
 678                 ctype->modifiers = old | mod | extra;
 679         }
 680
 681         /* Context */
 682         concat_ptr_list((struct ptr_list *)thistype->contexts,
 683                         (struct ptr_list **)&ctype->contexts);
 684
 685         /* Alignment */
 686         if (thistype->alignment & (thistype->alignment-1)) {
 687                 warning(pos, "I don't like non-power-of-2 alignments");
 688                 thistype->alignment = 0;
 689         }
 690         if (thistype->alignment > ctype->alignment)
 691                 ctype->alignment = thistype->alignment;
 692
 693         /* Address space */
 694         if (thistype->as)
 695                 ctype->as = thistype->as;
 696 }
 697
 698 static void check_modifiers(struct position *pos, struct symbol *s, unsigned long mod)
 699 {
 700         unsigned long banned, wrong;
 701         unsigned long this_mod = s->ctype.modifiers;
 702         const unsigned long BANNED_SIZE = MOD_LONG | MOD_LONGLONG | MOD_SHORT;
 703         const unsigned long BANNED_SIGN = MOD_SIGNED | MOD_UNSIGNED;
 704
 705         if (this_mod & (MOD_STRUCTOF | MOD_UNIONOF | MOD_ENUMOF))
 706                 banned = BANNED_SIZE | BANNED_SIGN;
 707         else if (this_mod & MOD_SPECIALBITS)
 708                 banned = 0;
 709         else if (s->ctype.base_type == &fp_type)
 710                 banned = BANNED_SIGN;
 711         else if (s->ctype.base_type == &int_type || !s->ctype.base_type || is_int_type (s))
 712                 banned = 0;
 713         else {
 714                 // label_type
 715                 // void_type
 716                 // bad_type
 717                 // vector_type <-- whatever that is
 718                 banned = BANNED_SIZE | BANNED_SIGN;
 719         }
 720
 721         wrong = mod & banned;
 722         if (wrong)
 723                 sparse_error(*pos, "modifier %sis invalid in this context",
 724                      modifier_string (wrong));
 725 }
 726
 727
 728 static struct token *declaration_specifiers(struct token *next, struct ctype *ctype, int qual)
 729 {
 730         struct token *token;
 731
 732         while ( (token = next) != NULL ) {
 733                 struct ctype thistype;
 734                 struct ident *ident;
 735                 struct symbol *s, *type;
 736                 unsigned long mod;
 737
 738                 next = token->next;
 739                 if (token_type(token) != TOKEN_IDENT)
 740                         break;
 741                 ident = token->ident;
 742
 743                 s = lookup_symbol(ident, NS_TYPEDEF);
 744                 if (!s)
 745                         break;
 746                 thistype = s->ctype;
 747                 mod = thistype.modifiers;
 748                 if (qual && (mod & ~(MOD_ATTRIBUTE | MOD_CONST | MOD_VOLATILE)))
 749                         break;
 750                 if (mod & MOD_SPECIALBITS) {
 751                         if (mod & MOD_STRUCTOF)
 752                                 next = struct_or_union_specifier(SYM_STRUCT, next, &thistype);
 753                         else if (mod & MOD_UNIONOF)
 754                                 next = struct_or_union_specifier(SYM_UNION, next, &thistype);
 755                         else if (mod & MOD_ENUMOF)
 756                                 next = enum_specifier(next, &thistype);
 757                         else if (mod & MOD_ATTRIBUTE)
 758                                 next = attribute_specifier(next, &thistype);
 759                         else if (mod & MOD_TYPEOF)
 760                                 next = typeof_specifier(next, &thistype);
 761                         mod = thistype.modifiers;
 762                 }
 763                 type = thistype.base_type;
 764                 if (type) {
 765                         if (qual)
 766                                 break;
 767                         if (ctype->base_type)
 768                                 break;
 769                         /* User types only mix with qualifiers */
 770                         if (mod & MOD_USERTYPE) {
 771                                 if (ctype->modifiers & MOD_SPECIFIER)
 772                                         break;
 773                         }
 774                         ctype->base_type = type;
 775                 }
 776
 777                 check_modifiers(&token->pos, s, ctype->modifiers);
 778                 apply_ctype(token->pos, &thistype, ctype);
 779         }
 780
 781         /* Turn the "virtual types" into real types with real sizes etc */
 782         if (!ctype->base_type) {
 783                 struct symbol *base = &incomplete_ctype;
 784
 785                 /*
 786                  * If we have modifiers, we'll default to an integer
 787                  * type, and "ctype_integer()" will turn this into
 788                  * a specific one.
 789                  */
 790                 if (ctype->modifiers & MOD_SPECIFIER)
 791                         base = &int_type;
 792                 ctype->base_type = base;
 793         }
 794         if (ctype->base_type == &int_type) {
 795                 ctype->base_type = ctype_integer(ctype->modifiers);
 796                 ctype->modifiers &= ~MOD_SPECIFIER;
 797         } else if (ctype->base_type == &fp_type) {
 798                 ctype->base_type = ctype_fp(ctype->modifiers);
 799                 ctype->modifiers &= ~MOD_SPECIFIER;
 800         }
 801         if (ctype->modifiers & MOD_BITWISE) {
 802                 struct symbol *type;
 803                 ctype->modifiers &= ~(MOD_BITWISE | MOD_SPECIFIER);
 804                 if (!is_int_type(ctype->base_type)) {
 805                         sparse_error(token->pos, "invalid modifier");
 806                         return token;
 807                 }
 808                 type = alloc_symbol(token->pos, SYM_BASETYPE);
 809                 *type = *ctype->base_type;
 810                 type->ctype.base_type = ctype->base_type;
 811                 type->type = SYM_RESTRICT;
 812                 type->ctype.modifiers &= ~MOD_SPECIFIER;
 813                 ctype->base_type = type;
 814                 create_fouled(type);
 815         }
 816         return token;
 817 }
 818
 819 static struct token *abstract_array_declarator(struct token *token, struct symbol *sym)
 820 {
 821         struct expression *expr = NULL;
 822
 823         token = parse_expression(token, &expr);
 824         sym->array_size = expr;
 825         return token;
 826 }
 827
 828 static struct token *parameter_type_list(struct token *, struct symbol *, struct ident **p);
 829 static struct token *declarator(struct token *token, struct symbol *sym, struct ident **p);
 830
 831 static struct token *handle_attributes(struct token *token, struct ctype *ctype)
 832 {
 833         for (;;) {
 834                 if (token_type(token) != TOKEN_IDENT)
 835                         break;
 836                 if (match_idents(token, &__attribute___ident, &__attribute_ident, NULL)) {
 837                         struct ctype thistype = { 0, };
 838                         token = attribute_specifier(token->next, &thistype);
 839                         apply_ctype(token->pos, &thistype, ctype);
 840                         continue;
 841                 }
 842                 if (match_idents(token, &asm_ident, &__asm_ident, &__asm___ident)) {
 843                         struct expression *expr;
 844                         token = expect(token->next, '(', "after asm");
 845                         token = parse_expression(token->next, &expr);
 846                         token = expect(token, ')', "after asm");
 847                         continue;
 848                 }
 849                 break;
 850         }
 851         return token;
 852 }
 853
 854 static struct token *direct_declarator(struct token *token, struct symbol *decl, struct ident **p)
 855 {
 856         struct ctype *ctype = &decl->ctype;
 857
 858         if (p && token_type(token) == TOKEN_IDENT) {
 859                 *p = token->ident;
 860                 token = token->next;
 861         }
 862
 863         for (;;) {
 864                 token = handle_attributes(token, ctype);
 865
 866                 if (token_type(token) != TOKEN_SPECIAL)
 867                         return token;
 868
 869                 /*
 870                  * This can be either a parameter list or a grouping.
 871                  * For the direct (non-abstract) case, we know if must be
 872                  * a parameter list if we already saw the identifier.
 873                  * For the abstract case, we know if must be a parameter
 874                  * list if it is empty or starts with a type.
 875                  */
 876                 if (token->special == '(') {
 877                         struct symbol *sym;
 878                         struct token *next = token->next;
 879                         int fn = (p && *p) || match_op(next, ')') || lookup_type(next);
 880
 881                         if (!fn) {
 882                                 struct symbol *base_type = ctype->base_type;
 883                                 token = declarator(next, decl, p);
 884                                 token = expect(token, ')', "in nested declarator");
 885                                 while (ctype->base_type != base_type)
 886                                         ctype = &ctype->base_type->ctype;
 887                                 p = NULL;
 888                                 continue;
 889                         }
 890
 891                         sym = indirect(token->pos, ctype, SYM_FN);
 892                         token = parameter_type_list(next, sym, p);
 893                         token = expect(token, ')', "in function declarator");
 894                         continue;
 895                 }
 896                 if (token->special == '[') {
 897                         struct symbol *array = indirect(token->pos, ctype, SYM_ARRAY);
 898                         token = abstract_array_declarator(token->next, array);
 899                         token = expect(token, ']', "in abstract_array_declarator");
 900                         ctype = &array->ctype;
 901                         continue;
 902                 }
 903                 break;
 904         }
 905         return token;
 906 }
 907
 908 static struct token *pointer(struct token *token, struct ctype *ctype)
 909 {
 910         unsigned long modifiers;
 911         struct symbol *base_type;
 912
 913         modifiers = ctype->modifiers & ~(MOD_TYPEDEF | MOD_ATTRIBUTE);
 914         base_type = ctype->base_type;
 915         ctype->modifiers = modifiers;
 916
 917         while (match_op(token,'*')) {
 918                 struct symbol *ptr = alloc_symbol(token->pos, SYM_PTR);
 919                 ptr->ctype.modifiers = modifiers & ~MOD_STORAGE;
 920                 ptr->ctype.as = ctype->as;
 921                 concat_ptr_list((struct ptr_list *)ctype->contexts,
 922                                 (struct ptr_list **)&ptr->ctype.contexts);
 923                 ptr->ctype.base_type = base_type;
 924
 925                 base_type = ptr;
 926                 ctype->modifiers = modifiers & MOD_STORAGE;
 927                 ctype->base_type = base_type;
 928                 ctype->as = 0;
 929                 free_ptr_list(&ctype->contexts);
 930
 931                 token = declaration_specifiers(token->next, ctype, 1);
 932                 modifiers = ctype->modifiers;
 933         }
 934         return token;
 935 }
 936
 937 static struct token *declarator(struct token *token, struct symbol *sym, struct ident **p)
 938 {
 939         token = pointer(token, &sym->ctype);
 940         return direct_declarator(token, sym, p);
 941 }
 942
 943 static struct token *handle_bitfield(struct token *token, struct symbol *decl)
 944 {
 945         struct ctype *ctype = &decl->ctype;
 946         struct expression *expr;
 947         struct symbol *bitfield;
 948         long long width;
 949
 950         if (!is_int_type(ctype->base_type)) {
 951                 sparse_error(token->pos, "invalid bitfield specifier for type %s.",
 952                         show_typename(ctype->base_type));
 953                 // Parse this to recover gracefully.
 954                 return conditional_expression(token->next, &expr);
 955         }
 956
 957         bitfield = indirect(token->pos, ctype, SYM_BITFIELD);
 958         token = conditional_expression(token->next, &expr);
 959         width = get_expression_value(expr);
 960         bitfield->bit_size = width;
 961
 962         if (width < 0 || width > INT_MAX) {
 963                 sparse_error(token->pos, "invalid bitfield width, %lld.", width);
 964                 width = -1;
 965         } else if (decl->ident && width == 0) {
 966                 sparse_error(token->pos, "invalid named zero-width bitfield `%s'",
 967                      show_ident(decl->ident));
 968                 width = -1;
 969         } else if (decl->ident) {
 970                 struct symbol *base_type = bitfield->ctype.base_type;
 971                 int is_signed = !(base_type->ctype.modifiers & MOD_UNSIGNED);
 972                 if (Wone_bit_signed_bitfield && width == 1 && is_signed) {
 973                         // Valid values are either {-1;0} or {0}, depending on integer
 974                         // representation.  The latter makes for very efficient code...
 975                         sparse_error(token->pos, "dubious one-bit signed bitfield");
 976                 }
 977                 if (Wdefault_bitfield_sign &&
 978                     base_type->type != SYM_ENUM &&
 979                     !(base_type->ctype.modifiers & MOD_EXPLICITLY_SIGNED) &&
 980                     is_signed) {
 981                         // The sign of bitfields is unspecified by default.
 982                         sparse_error(token->pos, "dubious bitfield without explicit `signed' or `unsigned'");
 983                 }
 984         }
 985         bitfield->bit_size = width;
 986         return token;
 987 }
 988
 989 static struct token *declaration_list(struct token *token, struct symbol_list **list)
 990 {
 991         struct ctype ctype = {0, };
 992
 993         token = declaration_specifiers(token, &ctype, 0);
 994         for (;;) {
 995                 struct ident *ident = NULL;
 996                 struct symbol *decl = alloc_symbol(token->pos, SYM_NODE);
 997                 decl->ctype = ctype;
 998                 token = declarator(token, decl, &ident);
 999                 decl->ident = ident;
1000                 if (match_op(token, ':')) {
1001                         token = handle_bitfield(token, decl);
1002                         token = handle_attributes(token, &decl->ctype);
1003                 }
1004                 add_symbol(list, decl);
1005                 if (!match_op(token, ','))
1006                         break;
1007                 token = token->next;
1008         }
1009         return token;
1010 }
1011
1012 static struct token *struct_declaration_list(struct token *token, struct symbol_list **list)
1013 {
1014         while (!match_op(token, '}')) {
1015                 token = declaration_list(token, list);
1016                 if (!match_op(token, ';')) {
1017                         sparse_error(token->pos, "expected ; at end of declaration");
1018                         break;
1019                 }
1020                 token = token->next;
1021         }
1022         return token;
1023 }
1024
1025 static struct token *parameter_declaration(struct token *token, struct symbol **tree)
1026 {
1027         struct ident *ident = NULL;
1028         struct symbol *sym;
1029         struct ctype ctype = { 0, };
1030
1031         token = declaration_specifiers(token, &ctype, 0);
1032         sym = alloc_symbol(token->pos, SYM_NODE);
1033         sym->ctype = ctype;
1034         *tree = sym;
1035         token = declarator(token, sym, &ident);
1036         sym->ident = ident;
1037         return token;
1038 }
1039
1040 struct token *typename(struct token *token, struct symbol **p)
1041 {
1042         struct symbol *sym = alloc_symbol(token->pos, SYM_NODE);
1043         *p = sym;
1044         token = declaration_specifiers(token, &sym->ctype, 0);
1045         return declarator(token, sym, NULL);
1046 }
1047
1048 static struct token *expression_statement(struct token *token, struct expression **tree)
1049 {
1050         token = parse_expression(token, tree);
1051         return expect(token, ';', "at end of statement");
1052 }
1053
1054 static struct token *parse_asm_operands(struct token *token, struct statement *stmt,
1055         struct expression_list **inout)
1056 {
1057         struct expression *expr;
1058
1059         /* Allow empty operands */
1060         if (match_op(token->next, ':') || match_op(token->next, ')'))
1061                 return token->next;
1062         do {
1063                 struct ident *ident = NULL;
1064                 if (match_op(token->next, '[') &&
1065                     token_type(token->next->next) == TOKEN_IDENT &&
1066                     match_op(token->next->next->next, ']')) {
1067                         ident = token->next->next->ident;
1068                         token = token->next->next->next;
1069                 }
1070                 add_expression(inout, (struct expression *)ident); /* UGGLEE!!! */
1071                 token = primary_expression(token->next, &expr);
1072                 add_expression(inout, expr);
1073                 token = parens_expression(token, &expr, "in asm parameter");
1074                 add_expression(inout, expr);
1075         } while (match_op(token, ','));
1076         return token;
1077 }
1078
1079 static struct token *parse_asm_clobbers(struct token *token, struct statement *stmt,
1080         struct expression_list **clobbers)
1081 {
1082         struct expression *expr;
1083
1084         do {
1085                 token = primary_expression(token->next, &expr);
1086                 add_expression(clobbers, expr);
1087         } while (match_op(token, ','));
1088         return token;
1089 }
1090
1091 static struct token *parse_asm(struct token *token, struct statement *stmt)
1092 {
1093         stmt->type = STMT_ASM;
1094         if (match_idents(token, &__volatile___ident, &__volatile_ident, &volatile_ident, NULL)) {
1095                 token = token->next;
1096         }
1097         token = expect(token, '(', "after asm");
1098         token = parse_expression(token, &stmt->asm_string);
1099         if (match_op(token, ':'))
1100                 token = parse_asm_operands(token, stmt, &stmt->asm_outputs);
1101         if (match_op(token, ':'))
1102                 token = parse_asm_operands(token, stmt, &stmt->asm_inputs);
1103         if (match_op(token, ':'))
1104                 token = parse_asm_clobbers(token, stmt, &stmt->asm_clobbers);
1105         token = expect(token, ')', "after asm");
1106         return expect(token, ';', "at end of asm-statement");
1107 }
1108
1109 /* Make a statement out of an expression */
1110 static struct statement *make_statement(struct expression *expr)
1111 {
1112         struct statement *stmt;
1113
1114         if (!expr)
1115                 return NULL;
1116         stmt = alloc_statement(expr->pos, STMT_EXPRESSION);
1117         stmt->expression = expr;
1118         return stmt;
1119 }
1120
1121 /*
1122  * All iterators have two symbols associated with them:
1123  * the "continue" and "break" symbols, which are targets
1124  * for continue and break statements respectively.
1125  *
1126  * They are in a special name-space, but they follow
1127  * all the normal visibility rules, so nested iterators
1128  * automatically work right.
1129  */
1130 static void start_iterator(struct statement *stmt)
1131 {
1132         struct symbol *cont, *brk;
1133
1134         start_symbol_scope();
1135         cont = alloc_symbol(stmt->pos, SYM_NODE);
1136         bind_symbol(cont, &continue_ident, NS_ITERATOR);
1137         brk = alloc_symbol(stmt->pos, SYM_NODE);
1138         bind_symbol(brk, &break_ident, NS_ITERATOR);
1139
1140         stmt->type = STMT_ITERATOR;
1141         stmt->iterator_break = brk;
1142         stmt->iterator_continue = cont;
1143         fn_local_symbol(brk);
1144         fn_local_symbol(cont);
1145 }
1146
1147 static void end_iterator(struct statement *stmt)
1148 {
1149         end_symbol_scope();
1150 }
1151
1152 static struct statement *start_function(struct symbol *sym)
1153 {
1154         struct symbol *ret;
1155         struct statement *stmt = alloc_statement(sym->pos, STMT_COMPOUND);
1156
1157         start_function_scope();
1158         ret = alloc_symbol(sym->pos, SYM_NODE);
1159         ret->ctype = sym->ctype.base_type->ctype;
1160         ret->ctype.modifiers &= ~(MOD_STORAGE | MOD_CONST | MOD_VOLATILE | MOD_INLINE | MOD_ADDRESSABLE | MOD_NOCAST | MOD_NODEREF | MOD_ACCESSED | MOD_TOPLEVEL);
1161         ret->ctype.modifiers |= (MOD_AUTO | MOD_REGISTER);
1162         bind_symbol(ret, &return_ident, NS_ITERATOR);
1163         stmt->ret = ret;
1164         fn_local_symbol(ret);
1165
1166         // Currently parsed symbol for __func__/__FUNCTION__/__PRETTY_FUNCTION__
1167         current_fn = sym;
1168
1169         return stmt;
1170 }
1171
1172 static void end_function(struct symbol *sym)
1173 {
1174         current_fn = NULL;
1175         end_function_scope();
1176 }
1177
1178 /*
1179  * A "switch()" statement, like an iterator, has a
1180  * the "break" symbol associated with it. It works
1181  * exactly like the iterator break - it's the target
1182  * for any break-statements in scope, and means that
1183  * "break" handling doesn't even need to know whether
1184  * it's breaking out of an iterator or a switch.
1185  *
1186  * In addition, the "case" symbol is a marker for the
1187  * case/default statements to find the switch statement
1188  * that they are associated with.
1189  */
1190 static void start_switch(struct statement *stmt)
1191 {
1192         struct symbol *brk, *switch_case;
1193
1194         start_symbol_scope();
1195         brk = alloc_symbol(stmt->pos, SYM_NODE);
1196         bind_symbol(brk, &break_ident, NS_ITERATOR);
1197
1198         switch_case = alloc_symbol(stmt->pos, SYM_NODE);
1199         bind_symbol(switch_case, &case_ident, NS_ITERATOR);
1200         switch_case->stmt = stmt;
1201
1202         stmt->type = STMT_SWITCH;
1203         stmt->switch_break = brk;
1204         stmt->switch_case = switch_case;
1205
1206         fn_local_symbol(brk);
1207         fn_local_symbol(switch_case);
1208 }
1209
1210 static void end_switch(struct statement *stmt)
1211 {
1212         if (!stmt->switch_case->symbol_list)
1213                 warning(stmt->pos, "switch with no cases");
1214         end_symbol_scope();
1215 }
1216
1217 static void add_case_statement(struct statement *stmt)
1218 {
1219         struct symbol *target = lookup_symbol(&case_ident, NS_ITERATOR);
1220         struct symbol *sym;
1221
1222         if (!target) {
1223                 sparse_error(stmt->pos, "not in switch scope");
1224                 stmt->type = STMT_NONE;
1225                 return;
1226         }
1227         sym = alloc_symbol(stmt->pos, SYM_NODE);
1228         add_symbol(&target->symbol_list, sym);
1229         sym->stmt = stmt;
1230         stmt->case_label = sym;
1231         fn_local_symbol(sym);
1232 }
1233
1234 static struct token *parse_return_statement(struct token *token, struct statement *stmt)
1235 {
1236         struct symbol *target = lookup_symbol(&return_ident, NS_ITERATOR);
1237
1238         if (!target)
1239                 error_die(token->pos, "internal error: return without a function target");
1240         stmt->type = STMT_RETURN;
1241         stmt->ret_target = target;
1242         return expression_statement(token->next, &stmt->ret_value);
1243 }
1244
1245 static struct token *parse_for_statement(struct token *token, struct statement *stmt)
1246 {
1247         struct symbol_list *syms;
1248         struct expression *e1, *e2, *e3;
1249         struct statement *iterator;
1250
1251         start_iterator(stmt);
1252         token = expect(token->next, '(', "after 'for'");
1253
1254         syms = NULL;
1255         e1 = NULL;
1256         /* C99 variable declaration? */
1257         if (lookup_type(token)) {
1258                 token = external_declaration(token, &syms);
1259         } else {
1260                 token = parse_expression(token, &e1);
1261                 token = expect(token, ';', "in 'for'");
1262         }
1263         token = parse_expression(token, &e2);
1264         token = expect(token, ';', "in 'for'");
1265         token = parse_expression(token, &e3);
1266         token = expect(token, ')', "in 'for'");
1267         token = statement(token, &iterator);
1268
1269         stmt->iterator_syms = syms;
1270         stmt->iterator_pre_statement = make_statement(e1);
1271         stmt->iterator_pre_condition = e2;
1272         stmt->iterator_post_statement = make_statement(e3);
1273         stmt->iterator_post_condition = NULL;
1274         stmt->iterator_statement = iterator;
1275         end_iterator(stmt);
1276
1277         return token;
1278 }
1279
1280 static struct token *parse_while_statement(struct token *token, struct statement *stmt)
1281 {
1282         struct expression *expr;
1283         struct statement *iterator;
1284
1285         start_iterator(stmt);
1286         token = parens_expression(token->next, &expr, "after 'while'");
1287         token = statement(token, &iterator);
1288
1289         stmt->iterator_pre_condition = expr;
1290         stmt->iterator_post_condition = NULL;
1291         stmt->iterator_statement = iterator;
1292         end_iterator(stmt);
1293
1294         return token;
1295 }
1296
1297 static struct token *parse_do_statement(struct token *token, struct statement *stmt)
1298 {
1299         struct expression *expr;
1300         struct statement *iterator;
1301
1302         start_iterator(stmt);
1303         token = statement(token->next, &iterator);
1304         if (token_type(token) == TOKEN_IDENT && token->ident == &while_ident)
1305                 token = token->next;
1306         else
1307                 sparse_error(token->pos, "expected 'while' after 'do'");
1308         token = parens_expression(token, &expr, "after 'do-while'");
1309
1310         stmt->iterator_post_condition = expr;
1311         stmt->iterator_statement = iterator;
1312         end_iterator(stmt);
1313
1314         if (iterator && iterator->type != STMT_COMPOUND && Wdo_while)
1315                 warning(iterator->pos, "do-while statement is not a compound statement");
1316
1317         return expect(token, ';', "after statement");
1318 }
1319
1320 static struct token *statement(struct token *token, struct statement **tree)
1321 {
1322         struct statement *stmt = alloc_statement(token->pos, STMT_NONE);
1323
1324         *tree = stmt;
1325         if (token_type(token) == TOKEN_IDENT) {
1326                 if (token->ident == &if_ident) {
1327                         stmt->type = STMT_IF;
1328                         token = parens_expression(token->next, &stmt->if_conditional, "after if");
1329                         token = statement(token, &stmt->if_true);
1330                         if (token_type(token) != TOKEN_IDENT)
1331                                 return token;
1332                         if (token->ident != &else_ident)
1333                                 return token;
1334                         return statement(token->next, &stmt->if_false);
1335                 }
1336
1337                 if (token->ident == &return_ident)
1338                         return parse_return_statement(token, stmt);
1339
1340                 if (token->ident == &break_ident || token->ident == &continue_ident) {
1341                         struct symbol *target = lookup_symbol(token->ident, NS_ITERATOR);
1342                         stmt->type = STMT_GOTO;
1343                         stmt->goto_label = target;
1344                         if (!target)
1345                                 sparse_error(stmt->pos, "break/continue not in iterator scope");
1346                         return expect(token->next, ';', "at end of statement");
1347                 }
1348                 if (token->ident == &default_ident) {
1349                         token = token->next;
1350                         goto default_statement;
1351                 }
1352                 if (token->ident == &case_ident) {
1353                         token = parse_expression(token->next, &stmt->case_expression);
1354                         if (match_op(token, SPECIAL_ELLIPSIS))
1355                                 token = parse_expression(token->next, &stmt->case_to);
1356 default_statement:
1357                         stmt->type = STMT_CASE;
1358                         token = expect(token, ':', "after default/case");
1359                         add_case_statement(stmt);
1360                         return statement(token, &stmt->case_statement);
1361                 }
1362                 if (token->ident == &switch_ident) {
1363                         stmt->type = STMT_SWITCH;
1364                         start_switch(stmt);
1365                         token = parens_expression(token->next, &stmt->switch_expression, "after 'switch'");
1366                         token = statement(token, &stmt->switch_statement);
1367                         end_switch(stmt);
1368                         return token;
1369                 }
1370                 if (token->ident == &for_ident)
1371                         return parse_for_statement(token, stmt);
1372
1373                 if (token->ident == &while_ident)
1374                         return parse_while_statement(token, stmt);
1375
1376                 if (token->ident == &do_ident)
1377                         return parse_do_statement(token, stmt);
1378
1379                 if (token->ident == &goto_ident) {
1380                         stmt->type = STMT_GOTO;
1381                         token = token->next;
1382                         if (match_op(token, '*')) {
1383                                 token = parse_expression(token->next, &stmt->goto_expression);
1384                                 add_statement(&function_computed_goto_list, stmt);
1385                         } else if (token_type(token) == TOKEN_IDENT) {
1386                                 stmt->goto_label = label_symbol(token);
1387                                 token = token->next;
1388                         } else {
1389                                 sparse_error(token->pos, "Expected identifier or goto expression");
1390                         }
1391                         return expect(token, ';', "at end of statement");
1392                 }
1393                 if (match_idents(token, &asm_ident, &__asm___ident, &__asm_ident, NULL)) {
1394                         return parse_asm(token->next, stmt);
1395                 }
1396                 if (token->ident == &__context___ident) {
1397                         stmt->type = STMT_CONTEXT;
1398                         token = parse_expression(token->next, &stmt->expression);
1399                         if(stmt->expression->type == EXPR_PREOP
1400                            && stmt->expression->op == '('
1401                            && stmt->expression->unop->type == EXPR_COMMA) {
1402                                 struct expression *expr;
1403                                 expr = stmt->expression->unop;
1404                                 stmt->context = expr->left;
1405                                 stmt->expression = expr->right;
1406                         }
1407                         return expect(token, ';', "at end of statement");
1408                 }
1409                 if (token->ident == &__range___ident) {
1410                         stmt->type = STMT_RANGE;
1411                         token = assignment_expression(token->next, &stmt->range_expression);
1412                         token = expect(token, ',', "after range expression");
1413                         token = assignment_expression(token, &stmt->range_low);
1414                         token = expect(token, ',', "after low range");
1415                         token = assignment_expression(token, &stmt->range_high);
1416                         return expect(token, ';', "after range statement");
1417                 }
1418                 if (match_op(token->next, ':')) {
1419                         stmt->type = STMT_LABEL;
1420                         stmt->label_identifier = label_symbol(token);
1421                         return statement(token->next->next, &stmt->label_statement);
1422                 }
1423         }
1424
1425         if (match_op(token, '{')) {
1426                 stmt->type = STMT_COMPOUND;
1427                 start_symbol_scope();
1428                 token = compound_statement(token->next, stmt);
1429                 end_symbol_scope();
1430
1431                 return expect(token, '}', "at end of compound statement");
1432         }
1433
1434         stmt->type = STMT_EXPRESSION;
1435         return expression_statement(token, &stmt->expression);
1436 }
1437
1438 static struct token * statement_list(struct token *token, struct statement_list **list)
1439 {
1440         int seen_statement = 0;
1441         for (;;) {
1442                 struct statement * stmt;
1443                 if (eof_token(token))
1444                         break;
1445                 if (match_op(token, '}'))
1446                         break;
1447                 if (lookup_type(token)) {
1448                         if (seen_statement) {
1449                                 warning(token->pos, "mixing declarations and code");
1450                                 seen_statement = 0;
1451                         }
1452                         stmt = alloc_statement(token->pos, STMT_DECLARATION);
1453                         token = external_declaration(token, &stmt->declaration);
1454                 } else {
1455                         seen_statement = warn_on_mixed;
1456                         token = statement(token, &stmt);
1457                 }
1458                 add_statement(list, stmt);
1459         }
1460         return token;
1461 }
1462
1463 static struct token *parameter_type_list(struct token *token, struct symbol *fn, struct ident **p)
1464 {
1465         struct symbol_list **list = &fn->arguments;
1466
1467         if (match_op(token, ')')) {
1468                 // No warning for "void oink ();"
1469                 // Bug or feature: warns for "void oink () __attribute__ ((noreturn));"
1470                 if (p && !match_op(token->next, ';'))
1471                         warning(token->pos, "non-ANSI function declaration of function '%s'", show_ident(*p));
1472                 return token;
1473         }
1474
1475         for (;;) {
1476                 struct symbol *sym;
1477
1478                 if (match_op(token, SPECIAL_ELLIPSIS)) {
1479                         if (!*list)
1480                                 warning(token->pos, "variadic functions must have one named argument");
1481                         fn->variadic = 1;
1482                         token = token->next;
1483                         break;
1484                 }
1485
1486                 sym = alloc_symbol(token->pos, SYM_NODE);
1487                 token = parameter_declaration(token, &sym);
1488                 if (sym->ctype.base_type == &void_ctype) {
1489                         /* Special case: (void) */
1490                         if (!*list && !sym->ident)
1491                                 break;
1492                         warning(token->pos, "void parameter");
1493                 }
1494                 add_symbol(list, sym);
1495                 if (!match_op(token, ','))
1496                         break;
1497                 token = token->next;
1498
1499         }
1500         return token;
1501 }
1502
1503 struct token *compound_statement(struct token *token, struct statement *stmt)
1504 {
1505         token = statement_list(token, &stmt->stmts);
1506         return token;
1507 }
1508
1509 static struct expression *identifier_expression(struct token *token)
1510 {
1511         struct expression *expr = alloc_expression(token->pos, EXPR_IDENTIFIER);
1512         expr->expr_ident = token->ident;
1513         return expr;
1514 }
1515
1516 static struct expression *index_expression(struct expression *from, struct expression *to)
1517 {
1518         int idx_from, idx_to;
1519         struct expression *expr = alloc_expression(from->pos, EXPR_INDEX);
1520
1521         idx_from = get_expression_value(from);
1522         idx_to = idx_from;
1523         if (to) {
1524                 idx_to = get_expression_value(to);
1525                 if (idx_to < idx_from || idx_from < 0)
1526                         warning(from->pos, "nonsense array initializer index range");
1527         }
1528         expr->idx_from = idx_from;
1529         expr->idx_to = idx_to;
1530         return expr;
1531 }
1532
1533 static struct token *single_initializer(struct expression **ep, struct token *token)
1534 {
1535         int expect_equal = 0;
1536         struct token *next = token->next;
1537         struct expression **tail = ep;
1538         int nested;
1539
1540         *ep = NULL;
1541
1542         if ((token_type(token) == TOKEN_IDENT) && match_op(next, ':')) {
1543                 struct expression *expr = identifier_expression(token);
1544                 warning(token->pos, "obsolete struct initializer, use C99 syntax");
1545                 token = initializer(&expr->ident_expression, next->next);
1546                 if (expr->ident_expression)
1547                         *ep = expr;
1548                 return token;
1549         }
1550
1551         for (tail = ep, nested = 0; ; nested++, next = token->next) {
1552                 if (match_op(token, '.') && (token_type(next) == TOKEN_IDENT)) {
1553                         struct expression *expr = identifier_expression(next);
1554                         *tail = expr;
1555                         tail = &expr->ident_expression;
1556                         expect_equal = 1;
1557                         token = next->next;
1558                 } else if (match_op(token, '[')) {
1559                         struct expression *from = NULL, *to = NULL, *expr;
1560                         token = constant_expression(token->next, &from);
1561                         if (!from) {
1562                                 sparse_error(token->pos, "Expected constant expression");
1563                                 break;
1564                         }
1565                         if (match_op(token, SPECIAL_ELLIPSIS))
1566                                 token = constant_expression(token->next, &to);
1567                         expr = index_expression(from, to);
1568                         *tail = expr;
1569                         tail = &expr->idx_expression;
1570                         token = expect(token, ']', "at end of initializer index");
1571                         if (nested)
1572                                 expect_equal = 1;
1573                 } else {
1574                         break;
1575                 }
1576         }
1577         if (nested && !expect_equal) {
1578                 if (!match_op(token, '='))
1579                         warning(token->pos, "obsolete array initializer, use C99 syntax");
1580                 else
1581                         expect_equal = 1;
1582         }
1583         if (expect_equal)
1584                 token = expect(token, '=', "at end of initializer index");
1585
1586         token = initializer(tail, token);
1587         if (!*tail)
1588                 *ep = NULL;
1589         return token;
1590 }
1591
1592 static struct token *initializer_list(struct expression_list **list, struct token *token)
1593 {
1594         struct expression *expr;
1595
1596         for (;;) {
1597                 token = single_initializer(&expr, token);
1598                 if (!expr)
1599                         break;
1600                 add_expression(list, expr);
1601                 if (!match_op(token, ','))
1602                         break;
1603                 token = token->next;
1604         }
1605         return token;
1606 }
1607
1608 struct token *initializer(struct expression **tree, struct token *token)
1609 {
1610         if (match_op(token, '{')) {
1611                 struct expression *expr = alloc_expression(token->pos, EXPR_INITIALIZER);
1612                 *tree = expr;
1613                 token = initializer_list(&expr->expr_list, token->next);
1614                 return expect(token, '}', "at end of initializer");
1615         }
1616         return assignment_expression(token, tree);
1617 }
1618
1619 static void declare_argument(struct symbol *sym, struct symbol *fn)
1620 {
1621         if (!sym->ident) {
1622                 sparse_error(sym->pos, "no identifier for function argument");
1623                 return;
1624         }
1625         bind_symbol(sym, sym->ident, NS_SYMBOL);
1626 }
1627
1628 static struct token *parse_function_body(struct token *token, struct symbol *decl,
1629         struct symbol_list **list)
1630 {
1631         struct symbol_list **old_symbol_list;
1632         struct symbol *base_type = decl->ctype.base_type;
1633         struct statement *stmt, **p;
1634         struct symbol *arg;
1635
1636         old_symbol_list = function_symbol_list;
1637         if (decl->ctype.modifiers & MOD_INLINE) {
1638                 function_symbol_list = &decl->inline_symbol_list;
1639                 p = &base_type->inline_stmt;
1640         } else {
1641                 function_symbol_list = &decl->symbol_list;
1642                 p = &base_type->stmt;
1643         }
1644         function_computed_target_list = NULL;
1645         function_computed_goto_list = NULL;
1646
1647         if (decl->ctype.modifiers & MOD_EXTERN) {
1648                 if (!(decl->ctype.modifiers & MOD_INLINE))
1649                         warning(decl->pos, "function '%s' with external linkage has definition", show_ident(decl->ident));
1650         }
1651         if (!(decl->ctype.modifiers & MOD_STATIC))
1652                 decl->ctype.modifiers |= MOD_EXTERN;
1653
1654         stmt = start_function(decl);
1655
1656         *p = stmt;
1657         FOR_EACH_PTR (base_type->arguments, arg) {
1658                 declare_argument(arg, base_type);
1659         } END_FOR_EACH_PTR(arg);
1660
1661         token = compound_statement(token->next, stmt);
1662
1663         end_function(decl);
1664         if (!(decl->ctype.modifiers & MOD_INLINE))
1665                 add_symbol(list, decl);
1666         check_declaration(decl);
1667         function_symbol_list = old_symbol_list;
1668         if (function_computed_goto_list) {
1669                 if (!function_computed_target_list)
1670                         warning(decl->pos, "function '%s' has computed goto but no targets?", show_ident(decl->ident));
1671                 else {
1672                         struct statement *stmt;
1673                         FOR_EACH_PTR(function_computed_goto_list, stmt) {
1674                                 stmt->target_list = function_computed_target_list;
1675                         } END_FOR_EACH_PTR(stmt);
1676                 }
1677         }
1678         return expect(token, '}', "at end of function");
1679 }
1680
1681 static void promote_k_r_types(struct symbol *arg)
1682 {
1683         struct symbol *base = arg->ctype.base_type;
1684         if (base && base->ctype.base_type == &int_type && (base->ctype.modifiers & (MOD_CHAR | MOD_SHORT))) {
1685                 arg->ctype.base_type = &int_ctype;
1686         }
1687 }
1688
1689 static void apply_k_r_types(struct symbol_list *argtypes, struct symbol *fn)
1690 {
1691         struct symbol_list *real_args = fn->ctype.base_type->arguments;
1692         struct symbol *arg;
1693
1694         FOR_EACH_PTR(real_args, arg) {
1695                 struct symbol *type;
1696
1697                 /* This is quadratic in the number of arguments. We _really_ don't care */
1698                 FOR_EACH_PTR(argtypes, type) {
1699                         if (type->ident == arg->ident)
1700                                 goto match;
1701                 } END_FOR_EACH_PTR(type);
1702                 sparse_error(arg->pos, "missing type declaration for parameter '%s'", show_ident(arg->ident));
1703                 continue;
1704 match:
1705                 type->used = 1;
1706                 /* "char" and "short" promote to "int" */
1707                 promote_k_r_types(type);
1708
1709                 arg->ctype = type->ctype;
1710         } END_FOR_EACH_PTR(arg);
1711
1712         FOR_EACH_PTR(argtypes, arg) {
1713                 if (!arg->used)
1714                         warning(arg->pos, "nonsensical parameter declaration '%s'", show_ident(arg->ident));
1715         } END_FOR_EACH_PTR(arg);
1716
1717 }
1718
1719 static struct token *parse_k_r_arguments(struct token *token, struct symbol *decl,
1720         struct symbol_list **list)
1721 {
1722         struct symbol_list *args = NULL;
1723
1724         warning(token->pos, "non-ANSI definition of function '%s'", show_ident(decl->ident));
1725         do {
1726                 token = declaration_list(token, &args);
1727                 if (!match_op(token, ';')) {
1728                         sparse_error(token->pos, "expected ';' at end of parameter declaration");
1729                         break;
1730                 }
1731                 token = token->next;
1732         } while (lookup_type(token));
1733
1734         apply_k_r_types(args, decl);
1735
1736         if (!match_op(token, '{')) {
1737                 sparse_error(token->pos, "expected function body");
1738                 return token;
1739         }
1740         return parse_function_body(token, decl, list);
1741 }
1742
1743
1744 struct token *external_declaration(struct token *token, struct symbol_list **list)
1745 {
1746         struct ident *ident = NULL;
1747         struct symbol *decl;
1748         struct ctype ctype = { 0, };
1749         struct symbol *base_type;
1750         int is_typedef;
1751
1752         /* Top-level inline asm? */
1753         if (match_idents(token, &asm_ident, &__asm___ident, &__asm_ident, NULL)) {
1754                 struct symbol *anon = alloc_symbol(token->pos, SYM_NODE);
1755                 struct symbol *fn = alloc_symbol(token->pos, SYM_FN);
1756                 struct statement *stmt;
1757
1758                 anon->ctype.base_type = fn;
1759                 stmt = alloc_statement(token->pos, STMT_NONE);
1760                 fn->stmt = stmt;
1761
1762                 token = parse_asm(token->next, stmt);
1763
1764                 add_symbol(list, anon);
1765                 return token;
1766         }
1767
1768         /* Parse declaration-specifiers, if any */
1769         token = declaration_specifiers(token, &ctype, 0);
1770         decl = alloc_symbol(token->pos, SYM_NODE);
1771         decl->ctype = ctype;
1772         token = declarator(token, decl, &ident);
1773
1774         /* Just a type declaration? */
1775         if (!ident)
1776                 return expect(token, ';', "end of type declaration");
1777
1778         /* type define declaration? */
1779         is_typedef = (ctype.modifiers & MOD_TYPEDEF) != 0;
1780
1781         /* Typedef's don't have meaningful storage */
1782         if (is_typedef) {
1783                 ctype.modifiers &= ~MOD_STORAGE;
1784                 decl->ctype.modifiers &= ~MOD_STORAGE;
1785                 decl->ctype.modifiers |= MOD_USERTYPE;
1786         }
1787
1788         bind_symbol(decl, ident, is_typedef ? NS_TYPEDEF: NS_SYMBOL);
1789
1790         base_type = decl->ctype.base_type;
1791
1792         if (is_typedef) {
1793                 if (base_type && !base_type->ident)
1794                         base_type->ident = ident;
1795         } else if (base_type && base_type->type == SYM_FN) {
1796                 /* K&R argument declaration? */
1797                 if (lookup_type(token))
1798                         return parse_k_r_arguments(token, decl, list);
1799                 if (match_op(token, '{'))
1800                         return parse_function_body(token, decl, list);
1801
1802                 if (!(decl->ctype.modifiers & MOD_STATIC))
1803                         decl->ctype.modifiers |= MOD_EXTERN;
1804         } else if (base_type == &void_ctype && !(decl->ctype.modifiers & MOD_EXTERN)) {
1805                 sparse_error(token->pos, "void declaration");
1806         }
1807
1808         for (;;) {
1809                 if (!is_typedef && match_op(token, '=')) {
1810                         if (decl->ctype.modifiers & MOD_EXTERN) {
1811                                 warning(decl->pos, "symbol with external linkage has initializer");
1812                                 decl->ctype.modifiers &= ~MOD_EXTERN;
1813                         }
1814                         token = initializer(&decl->initializer, token->next);
1815                 }
1816                 if (!is_typedef) {
1817                         if (!(decl->ctype.modifiers & (MOD_EXTERN | MOD_INLINE))) {
1818                                 add_symbol(list, decl);
1819                                 fn_local_symbol(decl);
1820                         }
1821                 }
1822                 check_declaration(decl);
1823
1824                 if (!match_op(token, ','))
1825                         break;
1826
1827                 token = token->next;
1828                 ident = NULL;
1829                 decl = alloc_symbol(token->pos, SYM_NODE);
1830                 decl->ctype = ctype;
1831                 token = declaration_specifiers(token, &decl->ctype, 1);
1832                 token = declarator(token, decl, &ident);
1833                 if (!ident) {
1834                         sparse_error(token->pos, "expected identifier name in type definition");
1835                         return token;
1836                 }
1837
1838                 bind_symbol(decl, ident, is_typedef ? NS_TYPEDEF: NS_SYMBOL);
1839
1840                 /* Function declarations are automatically extern unless specifically static */
1841                 base_type = decl->ctype.base_type;
1842                 if (!is_typedef && base_type && base_type->type == SYM_FN) {
1843                         if (!(decl->ctype.modifiers & MOD_STATIC))
1844                                 decl->ctype.modifiers |= MOD_EXTERN;
1845                 }
1846         }
1847         return expect(token, ';', "at end of declaration");
1848 }