Remove some unused files

1 files changed, 0 insertions, 3368 deletions

diff --git a/src/3p/chibicc/parse.c b/src/3p/chibicc/parse.c
deleted file mode 100644
index 6acaeb8..0000000
--- a/src/3p/chibicc/parse.c
+++ /dev/null
@@ -1,3368 +0,0 @@
-// This file contains a recursive descent parser for C.
-//
-// Most functions in this file are named after the symbols they are
-// supposed to read from an input token list. For example, stmt() is
-// responsible for reading a statement from a token list. The function
-// then construct an AST node representing a statement.
-//
-// Each function conceptually returns two values, an AST node and
-// remaining part of the input tokens. Since C doesn't support
-// multiple return values, the remaining tokens are returned to the
-// caller via a pointer argument.
-//
-// Input tokens are represented by a linked list. Unlike many recursive
-// descent parsers, we don't have the notion of the "input token stream".
-// Most parsing functions don't change the global state of the parser.
-// So it is very easy to lookahead arbitrary number of tokens in this
-// parser.
-
-#include "chibicc.h"
-
-// Scope for local variables, global variables, typedefs
-// or enum constants
-typedef struct {
-  Obj *var;
-  Type *type_def;
-  Type *enum_ty;
-  int enum_val;
-} VarScope;
-
-// Represents a block scope.
-typedef struct Scope Scope;
-struct Scope {
-  Scope *next;
-
-  // C has two block scopes; one is for variables/typedefs and
-  // the other is for struct/union/enum tags.
-  HashMap vars;
-  HashMap tags;
-};
-
-// Variable attributes such as typedef or extern.
-typedef struct {
-  bool is_typedef;
-  bool is_static;
-  bool is_extern;
-  bool is_inline;
-  bool is_tls;
-  int align;
-} VarAttr;
-
-// This struct represents a variable initializer. Since initializers
-// can be nested (e.g. `int x[2][2] = {{1, 2}, {3, 4}}`), this struct
-// is a tree data structure.
-typedef struct Initializer Initializer;
-struct Initializer {
-  Initializer *next;
-  Type *ty;
-  Token *tok;
-  bool is_flexible;
-
-  // If it's not an aggregate type and has an initializer,
-  // `expr` has an initialization expression.
-  Node *expr;
-
-  // If it's an initializer for an aggregate type (e.g. array or struct),
-  // `children` has initializers for its children.
-  Initializer **children;
-
-  // Only one member can be initialized for a union.
-  // `mem` is used to clarify which member is initialized.
-  Member *mem;
-};
-
-// For local variable initializer.
-typedef struct InitDesg InitDesg;
-struct InitDesg {
-  InitDesg *next;
-  int idx;
-  Member *member;
-  Obj *var;
-};
-
-// All local variable instances created during parsing are
-// accumulated to this list.
-static Obj *locals;
-
-// Likewise, global variables are accumulated to this list.
-static Obj *globals;
-
-static Scope *scope = &(Scope){};
-
-// Points to the function object the parser is currently parsing.
-static Obj *current_fn;
-
-// Lists of all goto statements and labels in the curent function.
-static Node *gotos;
-static Node *labels;
-
-// Current "goto" and "continue" jump targets.
-static char *brk_label;
-static char *cont_label;
-
-// Points to a node representing a switch if we are parsing
-// a switch statement. Otherwise, NULL.
-static Node *current_switch;
-
-static Obj *builtin_alloca;
-
-static bool is_typename(Token *tok);
-static Type *declspec(Token **rest, Token *tok, VarAttr *attr);
-static Type *typename(Token **rest, Token *tok);
-static Type *enum_specifier(Token **rest, Token *tok);
-static Type *typeof_specifier(Token **rest, Token *tok);
-static Type *type_suffix(Token **rest, Token *tok, Type *ty);
-static Type *declarator(Token **rest, Token *tok, Type *ty);
-static Node *declaration(Token **rest, Token *tok, Type *basety, VarAttr *attr);
-static void array_initializer2(Token **rest, Token *tok, Initializer *init, int i);
-static void struct_initializer2(Token **rest, Token *tok, Initializer *init, Member *mem);
-static void initializer2(Token **rest, Token *tok, Initializer *init);
-static Initializer *initializer(Token **rest, Token *tok, Type *ty, Type **new_ty);
-static Node *lvar_initializer(Token **rest, Token *tok, Obj *var);
-static void gvar_initializer(Token **rest, Token *tok, Obj *var);
-static Node *compound_stmt(Token **rest, Token *tok);
-static Node *stmt(Token **rest, Token *tok);
-static Node *expr_stmt(Token **rest, Token *tok);
-static Node *expr(Token **rest, Token *tok);
-static int64_t eval(Node *node);
-static int64_t eval2(Node *node, char ***label);
-static int64_t eval_rval(Node *node, char ***label);
-static bool is_const_expr(Node *node);
-static Node *assign(Token **rest, Token *tok);
-static Node *logor(Token **rest, Token *tok);
-static double eval_double(Node *node);
-static Node *conditional(Token **rest, Token *tok);
-static Node *logand(Token **rest, Token *tok);
-static Node *bitor(Token **rest, Token *tok);
-static Node *bitxor(Token **rest, Token *tok);
-static Node *bitand(Token **rest, Token *tok);
-static Node *equality(Token **rest, Token *tok);
-static Node *relational(Token **rest, Token *tok);
-static Node *shift(Token **rest, Token *tok);
-static Node *add(Token **rest, Token *tok);
-static Node *new_add(Node *lhs, Node *rhs, Token *tok);
-static Node *new_sub(Node *lhs, Node *rhs, Token *tok);
-static Node *mul(Token **rest, Token *tok);
-static Node *cast(Token **rest, Token *tok);
-static Member *get_struct_member(Type *ty, Token *tok);
-static Type *struct_decl(Token **rest, Token *tok);
-static Type *union_decl(Token **rest, Token *tok);
-static Node *postfix(Token **rest, Token *tok);
-static Node *funcall(Token **rest, Token *tok, Node *node);
-static Node *unary(Token **rest, Token *tok);
-static Node *primary(Token **rest, Token *tok);
-static Token *parse_typedef(Token *tok, Type *basety);
-static bool is_function(Token *tok);
-static Token *function(Token *tok, Type *basety, VarAttr *attr);
-static Token *global_variable(Token *tok, Type *basety, VarAttr *attr);
-
-static int align_down(int n, int align) {
-  return align_to(n - align + 1, align);
-}
-
-static void enter_scope(void) {
-  Scope *sc = calloc(1, sizeof(Scope));
-  sc->next = scope;
-  scope = sc;
-}
-
-static void leave_scope(void) {
-  scope = scope->next;
-}
-
-// Find a variable by name.
-static VarScope *find_var(Token *tok) {
-  for (Scope *sc = scope; sc; sc = sc->next) {
-    VarScope *sc2 = hashmap_get2(&sc->vars, tok->loc, tok->len);
-    if (sc2)
-      return sc2;
-  }
-  return NULL;
-}
-
-static Type *find_tag(Token *tok) {
-  for (Scope *sc = scope; sc; sc = sc->next) {
-    Type *ty = hashmap_get2(&sc->tags, tok->loc, tok->len);
-    if (ty)
-      return ty;
-  }
-  return NULL;
-}
-
-static Node *new_node(NodeKind kind, Token *tok) {
-  Node *node = calloc(1, sizeof(Node));
-  node->kind = kind;
-  node->tok = tok;
-  return node;
-}
-
-static Node *new_binary(NodeKind kind, Node *lhs, Node *rhs, Token *tok) {
-  Node *node = new_node(kind, tok);
-  node->lhs = lhs;
-  node->rhs = rhs;
-  return node;
-}
-
-static Node *new_unary(NodeKind kind, Node *expr, Token *tok) {
-  Node *node = new_node(kind, tok);
-  node->lhs = expr;
-  return node;
-}
-
-static Node *new_num(int64_t val, Token *tok) {
-  Node *node = new_node(ND_NUM, tok);
-  node->val = val;
-  return node;
-}
-
-static Node *new_long(int64_t val, Token *tok) {
-  Node *node = new_node(ND_NUM, tok);
-  node->val = val;
-  node->ty = ty_long;
-  return node;
-}
-
-static Node *new_ulong(long val, Token *tok) {
-  Node *node = new_node(ND_NUM, tok);
-  node->val = val;
-  node->ty = ty_ulong;
-  return node;
-}
-
-static Node *new_var_node(Obj *var, Token *tok) {
-  Node *node = new_node(ND_VAR, tok);
-  node->var = var;
-  return node;
-}
-
-static Node *new_vla_ptr(Obj *var, Token *tok) {
-  Node *node = new_node(ND_VLA_PTR, tok);
-  node->var = var;
-  return node;
-}
-
-Node *new_cast(Node *expr, Type *ty) {
-  add_type(expr);
-
-  Node *node = calloc(1, sizeof(Node));
-  node->kind = ND_CAST;
-  node->tok = expr->tok;
-  node->lhs = expr;
-  node->ty = copy_type(ty);
-  return node;
-}
-
-static VarScope *push_scope(char *name) {
-  VarScope *sc = calloc(1, sizeof(VarScope));
-  hashmap_put(&scope->vars, name, sc);
-  return sc;
-}
-
-static Initializer *new_initializer(Type *ty, bool is_flexible) {
-  Initializer *init = calloc(1, sizeof(Initializer));
-  init->ty = ty;
-
-  if (ty->kind == TY_ARRAY) {
-    if (is_flexible && ty->size < 0) {
-      init->is_flexible = true;
-      return init;
-    }
-
-    init->children = calloc(ty->array_len, sizeof(Initializer *));
-    for (int i = 0; i < ty->array_len; i++)
-      init->children[i] = new_initializer(ty->base, false);
-    return init;
-  }
-
-  if (ty->kind == TY_STRUCT || ty->kind == TY_UNION) {
-    // Count the number of struct members.
-    int len = 0;
-    for (Member *mem = ty->members; mem; mem = mem->next)
-      len++;
-
-    init->children = calloc(len, sizeof(Initializer *));
-
-    for (Member *mem = ty->members; mem; mem = mem->next) {
-      if (is_flexible && ty->is_flexible && !mem->next) {
-        Initializer *child = calloc(1, sizeof(Initializer));
-        child->ty = mem->ty;
-        child->is_flexible = true;
-        init->children[mem->idx] = child;
-      } else {
-        init->children[mem->idx] = new_initializer(mem->ty, false);
-      }
-    }
-    return init;
-  }
-
-  return init;
-}
-
-static Obj *new_var(char *name, Type *ty) {
-  Obj *var = calloc(1, sizeof(Obj));
-  var->name = name;
-  var->ty = ty;
-  var->align = ty->align;
-  push_scope(name)->var = var;
-  return var;
-}
-
-static Obj *new_lvar(char *name, Type *ty) {
-  Obj *var = new_var(name, ty);
-  var->is_local = true;
-  var->next = locals;
-  locals = var;
-  return var;
-}
-
-static Obj *new_gvar(char *name, Type *ty) {
-  Obj *var = new_var(name, ty);
-  var->next = globals;
-  var->is_static = true;
-  var->is_definition = true;
-  globals = var;
-  return var;
-}
-
-static char *new_unique_name(void) {
-  static int id = 0;
-  return format(".L..%d", id++);
-}
-
-static Obj *new_anon_gvar(Type *ty) {
-  return new_gvar(new_unique_name(), ty);
-}
-
-static Obj *new_string_literal(char *p, Type *ty) {
-  Obj *var = new_anon_gvar(ty);
-  var->init_data = p;
-  return var;
-}
-
-static char *get_ident(Token *tok) {
-  if (tok->kind != TK_IDENT)
-    error_tok(tok, "expected an identifier");
-  return strndup(tok->loc, tok->len);
-}
-
-static Type *find_typedef(Token *tok) {
-  if (tok->kind == TK_IDENT) {
-    VarScope *sc = find_var(tok);
-    if (sc)
-      return sc->type_def;
-  }
-  return NULL;
-}
-
-static void push_tag_scope(Token *tok, Type *ty) {
-  hashmap_put2(&scope->tags, tok->loc, tok->len, ty);
-}
-
-// declspec = ("void" | "_Bool" | "char" | "short" | "int" | "long"
-//             | "typedef" | "static" | "extern" | "inline"
-//             | "_Thread_local" | "__thread"
-//             | "signed" | "unsigned"
-//             | struct-decl | union-decl | typedef-name
-//             | enum-specifier | typeof-specifier
-//             | "const" | "volatile" | "auto" | "register" | "restrict"
-//             | "__restrict" | "__restrict__" | "_Noreturn")+
-//
-// The order of typenames in a type-specifier doesn't matter. For
-// example, `int long static` means the same as `static long int`.
-// That can also be written as `static long` because you can omit
-// `int` if `long` or `short` are specified. However, something like
-// `char int` is not a valid type specifier. We have to accept only a
-// limited combinations of the typenames.
-//
-// In this function, we count the number of occurrences of each typename
-// while keeping the "current" type object that the typenames up
-// until that point represent. When we reach a non-typename token,
-// we returns the current type object.
-static Type *declspec(Token **rest, Token *tok, VarAttr *attr) {
-  // We use a single integer as counters for all typenames.
-  // For example, bits 0 and 1 represents how many times we saw the
-  // keyword "void" so far. With this, we can use a switch statement
-  // as you can see below.
-  enum {
-    VOID     = 1 << 0,
-    BOOL     = 1 << 2,
-    CHAR     = 1 << 4,
-    SHORT    = 1 << 6,
-    INT      = 1 << 8,
-    LONG     = 1 << 10,
-    FLOAT    = 1 << 12,
-    DOUBLE   = 1 << 14,
-    OTHER    = 1 << 16,
-    SIGNED   = 1 << 17,
-    UNSIGNED = 1 << 18,
-  };
-
-  Type *ty = ty_int;
-  int counter = 0;
-  bool is_atomic = false;
-
-  while (is_typename(tok)) {
-    // Handle storage class specifiers.
-    if (equal(tok, "typedef") || equal(tok, "static") || equal(tok, "extern") ||
-        equal(tok, "inline") || equal(tok, "_Thread_local") || equal(tok, "__thread")) {
-      if (!attr)
-        error_tok(tok, "storage class specifier is not allowed in this context");
-
-      if (equal(tok, "typedef"))
-        attr->is_typedef = true;
-      else if (equal(tok, "static"))
-        attr->is_static = true;
-      else if (equal(tok, "extern"))
-        attr->is_extern = true;
-      else if (equal(tok, "inline"))
-        attr->is_inline = true;
-      else
-        attr->is_tls = true;
-
-      if (attr->is_typedef &&
-          attr->is_static + attr->is_extern + attr->is_inline + attr->is_tls > 1)
-        error_tok(tok, "typedef may not be used together with static,"
-                  " extern, inline, __thread or _Thread_local");
-      tok = tok->next;
-      continue;
-    }
-
-    // These keywords are recognized but ignored.
-    if (consume(&tok, tok, "const") || consume(&tok, tok, "volatile") ||
-        consume(&tok, tok, "auto") || consume(&tok, tok, "register") ||
-        consume(&tok, tok, "restrict") || consume(&tok, tok, "__restrict") ||
-        consume(&tok, tok, "__restrict__") || consume(&tok, tok, "_Noreturn"))
-      continue;
-
-    if (equal(tok, "_Atomic")) {
-      tok = tok->next;
-      if (equal(tok , "(")) {
-        ty = typename(&tok, tok->next);
-        tok = skip(tok, ")");
-      }
-      is_atomic = true;
-      continue;
-    }
-
-    if (equal(tok, "_Alignas")) {
-      if (!attr)
-        error_tok(tok, "_Alignas is not allowed in this context");
-      tok = skip(tok->next, "(");
-
-      if (is_typename(tok))
-        attr->align = typename(&tok, tok)->align;
-      else
-        attr->align = const_expr(&tok, tok);
-      tok = skip(tok, ")");
-      continue;
-    }
-
-    // Handle user-defined types.
-    Type *ty2 = find_typedef(tok);
-    if (equal(tok, "struct") || equal(tok, "union") || equal(tok, "enum") ||
-        equal(tok, "typeof") || ty2) {
-      if (counter)
-        break;
-
-      if (equal(tok, "struct")) {
-        ty = struct_decl(&tok, tok->next);
-      } else if (equal(tok, "union")) {
-        ty = union_decl(&tok, tok->next);
-      } else if (equal(tok, "enum")) {
-        ty = enum_specifier(&tok, tok->next);
-      } else if (equal(tok, "typeof")) {
-        ty = typeof_specifier(&tok, tok->next);
-      } else {
-        ty = ty2;
-        tok = tok->next;
-      }
-
-      counter += OTHER;
-      continue;
-    }
-
-    // Handle built-in types.
-    if (equal(tok, "void"))
-      counter += VOID;
-    else if (equal(tok, "_Bool"))
-      counter += BOOL;
-    else if (equal(tok, "char"))
-      counter += CHAR;
-    else if (equal(tok, "short"))
-      counter += SHORT;
-    else if (equal(tok, "int"))
-      counter += INT;
-    else if (equal(tok, "long"))
-      counter += LONG;
-    else if (equal(tok, "float"))
-      counter += FLOAT;
-    else if (equal(tok, "double"))
-      counter += DOUBLE;
-    else if (equal(tok, "signed"))
-      counter |= SIGNED;
-    else if (equal(tok, "unsigned"))
-      counter |= UNSIGNED;
-    else
-      unreachable();
-
-    switch (counter) {
-    case VOID:
-      ty = ty_void;
-      break;
-    case BOOL:
-      ty = ty_bool;
-      break;
-    case CHAR:
-    case SIGNED + CHAR:
-      ty = ty_char;
-      break;
-    case UNSIGNED + CHAR:
-      ty = ty_uchar;
-      break;
-    case SHORT:
-    case SHORT + INT:
-    case SIGNED + SHORT:
-    case SIGNED + SHORT + INT:
-      ty = ty_short;
-      break;
-    case UNSIGNED + SHORT:
-    case UNSIGNED + SHORT + INT:
-      ty = ty_ushort;
-      break;
-    case INT:
-    case SIGNED:
-    case SIGNED + INT:
-      ty = ty_int;
-      break;
-    case UNSIGNED:
-    case UNSIGNED + INT:
-      ty = ty_uint;
-      break;
-    case LONG:
-    case LONG + INT:
-    case LONG + LONG:
-    case LONG + LONG + INT:
-    case SIGNED + LONG:
-    case SIGNED + LONG + INT:
-    case SIGNED + LONG + LONG:
-    case SIGNED + LONG + LONG + INT:
-      ty = ty_long;
-      break;
-    case UNSIGNED + LONG:
-    case UNSIGNED + LONG + INT:
-    case UNSIGNED + LONG + LONG:
-    case UNSIGNED + LONG + LONG + INT:
-      ty = ty_ulong;
-      break;
-    case FLOAT:
-      ty = ty_float;
-      break;
-    case DOUBLE:
-      ty = ty_double;
-      break;
-    case LONG + DOUBLE:
-      ty = ty_ldouble;
-      break;
-    default:
-      error_tok(tok, "invalid type");
-    }
-
-    tok = tok->next;
-  }
-
-  if (is_atomic) {
-    ty = copy_type(ty);
-    ty->is_atomic = true;
-  }
-
-  *rest = tok;
-  return ty;
-}
-
-// func-params = ("void" | param ("," param)* ("," "...")?)? ")"
-// param       = declspec declarator
-static Type *func_params(Token **rest, Token *tok, Type *ty) {
-  if (equal(tok, "void") && equal(tok->next, ")")) {
-    *rest = tok->next->next;
-    return func_type(ty);
-  }
-
-  Type head = {};
-  Type *cur = &head;
-  bool is_variadic = false;
-
-  while (!equal(tok, ")")) {
-    if (cur != &head)
-      tok = skip(tok, ",");
-
-    if (equal(tok, "...")) {
-      is_variadic = true;
-      tok = tok->next;
-      skip(tok, ")");
-      break;
-    }
-
-    Type *ty2 = declspec(&tok, tok, NULL);
-    ty2 = declarator(&tok, tok, ty2);
-
-    Token *name = ty2->name;
-
-    if (ty2->kind == TY_ARRAY) {
-      // "array of T" is converted to "pointer to T" only in the parameter
-      // context. For example, *argv[] is converted to **argv by this.
-      ty2 = pointer_to(ty2->base);
-      ty2->name = name;
-    } else if (ty2->kind == TY_FUNC) {
-      // Likewise, a function is converted to a pointer to a function
-      // only in the parameter context.
-      ty2 = pointer_to(ty2);
-      ty2->name = name;
-    }
-
-    cur = cur->next = copy_type(ty2);
-  }
-
-  if (cur == &head)
-    is_variadic = true;
-
-  ty = func_type(ty);
-  ty->params = head.next;
-  ty->is_variadic = is_variadic;
-  *rest = tok->next;
-  return ty;
-}
-
-// array-dimensions = ("static" | "restrict")* const-expr? "]" type-suffix
-static Type *array_dimensions(Token **rest, Token *tok, Type *ty) {
-  while (equal(tok, "static") || equal(tok, "restrict"))
-    tok = tok->next;
-
-  if (equal(tok, "]")) {
-    ty = type_suffix(rest, tok->next, ty);
-    return array_of(ty, -1);
-  }
-
-  Node *expr = conditional(&tok, tok);
-  tok = skip(tok, "]");
-  ty = type_suffix(rest, tok, ty);
-
-  if (ty->kind == TY_VLA || !is_const_expr(expr))
-    return vla_of(ty, expr);
-  return array_of(ty, eval(expr));
-}
-
-// type-suffix = "(" func-params
-//             | "[" array-dimensions
-//             | ε
-static Type *type_suffix(Token **rest, Token *tok, Type *ty) {
-  if (equal(tok, "("))
-    return func_params(rest, tok->next, ty);
-
-  if (equal(tok, "["))
-    return array_dimensions(rest, tok->next, ty);
-
-  *rest = tok;
-  return ty;
-}
-
-// pointers = ("*" ("const" | "volatile" | "restrict")*)*
-static Type *pointers(Token **rest, Token *tok, Type *ty) {
-  while (consume(&tok, tok, "*")) {
-    ty = pointer_to(ty);
-    while (equal(tok, "const") || equal(tok, "volatile") || equal(tok, "restrict") ||
-           equal(tok, "__restrict") || equal(tok, "__restrict__"))
-      tok = tok->next;
-  }
-  *rest = tok;
-  return ty;
-}
-
-// declarator = pointers ("(" ident ")" | "(" declarator ")" | ident) type-suffix
-static Type *declarator(Token **rest, Token *tok, Type *ty) {
-  ty = pointers(&tok, tok, ty);
-
-  if (equal(tok, "(")) {
-    Token *start = tok;
-    Type dummy = {};
-    declarator(&tok, start->next, &dummy);
-    tok = skip(tok, ")");
-    ty = type_suffix(rest, tok, ty);
-    return declarator(&tok, start->next, ty);
-  }
-
-  Token *name = NULL;
-  Token *name_pos = tok;
-
-  if (tok->kind == TK_IDENT) {
-    name = tok;
-    tok = tok->next;
-  }
-
-  ty = type_suffix(rest, tok, ty);
-  ty->name = name;
-  ty->name_pos = name_pos;
-  return ty;
-}
-
-// abstract-declarator = pointers ("(" abstract-declarator ")")? type-suffix
-static Type *abstract_declarator(Token **rest, Token *tok, Type *ty) {
-  ty = pointers(&tok, tok, ty);
-
-  if (equal(tok, "(")) {
-    Token *start = tok;
-    Type dummy = {};
-    abstract_declarator(&tok, start->next, &dummy);
-    tok = skip(tok, ")");
-    ty = type_suffix(rest, tok, ty);
-    return abstract_declarator(&tok, start->next, ty);
-  }
-
-  return type_suffix(rest, tok, ty);
-}
-
-// type-name = declspec abstract-declarator
-static Type *typename(Token **rest, Token *tok) {
-  Type *ty = declspec(&tok, tok, NULL);
-  return abstract_declarator(rest, tok, ty);
-}
-
-static bool is_end(Token *tok) {
-  return equal(tok, "}") || (equal(tok, ",") && equal(tok->next, "}"));
-}
-
-static bool consume_end(Token **rest, Token *tok) {
-  if (equal(tok, "}")) {
-    *rest = tok->next;
-    return true;
-  }
-
-  if (equal(tok, ",") && equal(tok->next, "}")) {
-    *rest = tok->next->next;
-    return true;
-  }
-
-  return false;
-}
-
-// enum-specifier = ident? "{" enum-list? "}"
-//                | ident ("{" enum-list? "}")?
-//
-// enum-list      = ident ("=" num)? ("," ident ("=" num)?)* ","?
-static Type *enum_specifier(Token **rest, Token *tok) {
-  Type *ty = enum_type();
-
-  // Read a struct tag.
-  Token *tag = NULL;
-  if (tok->kind == TK_IDENT) {
-    tag = tok;
-    tok = tok->next;
-  }
-
-  if (tag && !equal(tok, "{")) {
-    Type *ty = find_tag(tag);
-    if (!ty)
-      error_tok(tag, "unknown enum type");
-    if (ty->kind != TY_ENUM)
-      error_tok(tag, "not an enum tag");
-    *rest = tok;
-    return ty;
-  }
-
-  tok = skip(tok, "{");
-
-  // Read an enum-list.
-  int i = 0;
-  int val = 0;
-  while (!consume_end(rest, tok)) {
-    if (i++ > 0)
-      tok = skip(tok, ",");
-
-    char *name = get_ident(tok);
-    tok = tok->next;
-
-    if (equal(tok, "="))
-      val = const_expr(&tok, tok->next);
-
-    VarScope *sc = push_scope(name);
-    sc->enum_ty = ty;
-    sc->enum_val = val++;
-  }
-
-  if (tag)
-    push_tag_scope(tag, ty);
-  return ty;
-}
-
-// typeof-specifier = "(" (expr | typename) ")"
-static Type *typeof_specifier(Token **rest, Token *tok) {
-  tok = skip(tok, "(");
-
-  Type *ty;
-  if (is_typename(tok)) {
-    ty = typename(&tok, tok);
-  } else {
-    Node *node = expr(&tok, tok);
-    add_type(node);
-    ty = node->ty;
-  }
-  *rest = skip(tok, ")");
-  return ty;
-}
-
-// Generate code for computing a VLA size.
-static Node *compute_vla_size(Type *ty, Token *tok) {
-  Node *node = new_node(ND_NULL_EXPR, tok);
-  if (ty->base)
-    node = new_binary(ND_COMMA, node, compute_vla_size(ty->base, tok), tok);
-
-  if (ty->kind != TY_VLA)
-    return node;
-
-  Node *base_sz;
-  if (ty->base->kind == TY_VLA)
-    base_sz = new_var_node(ty->base->vla_size, tok);
-  else
-    base_sz = new_num(ty->base->size, tok);
-
-  ty->vla_size = new_lvar("", ty_ulong);
-  Node *expr = new_binary(ND_ASSIGN, new_var_node(ty->vla_size, tok),
-                          new_binary(ND_MUL, ty->vla_len, base_sz, tok),
-                          tok);
-  return new_binary(ND_COMMA, node, expr, tok);
-}
-
-static Node *new_alloca(Node *sz) {
-  Node *node = new_unary(ND_FUNCALL, new_var_node(builtin_alloca, sz->tok), sz->tok);
-  node->func_ty = builtin_alloca->ty;
-  node->ty = builtin_alloca->ty->return_ty;
-  node->args = sz;
-  add_type(sz);
-  return node;
-}
-
-// declaration = declspec (declarator ("=" expr)? ("," declarator ("=" expr)?)*)? ";"
-static Node *declaration(Token **rest, Token *tok, Type *basety, VarAttr *attr) {
-  Node head = {};
-  Node *cur = &head;
-  int i = 0;
-
-  while (!equal(tok, ";")) {
-    if (i++ > 0)
-      tok = skip(tok, ",");
-
-    Type *ty = declarator(&tok, tok, basety);
-    if (ty->kind == TY_VOID)
-      error_tok(tok, "variable declared void");
-    if (!ty->name)
-      error_tok(ty->name_pos, "variable name omitted");
-
-    if (attr && attr->is_static) {
-      // static local variable
-      Obj *var = new_anon_gvar(ty);
-      push_scope(get_ident(ty->name))->var = var;
-      if (equal(tok, "="))
-        gvar_initializer(&tok, tok->next, var);
-      continue;
-    }
-
-    // Generate code for computing a VLA size. We need to do this
-    // even if ty is not VLA because ty may be a pointer to VLA
-    // (e.g. int (*foo)[n][m] where n and m are variables.)
-    cur = cur->next = new_unary(ND_EXPR_STMT, compute_vla_size(ty, tok), tok);
-
-    if (ty->kind == TY_VLA) {
-      if (equal(tok, "="))
-        error_tok(tok, "variable-sized object may not be initialized");
-
-      // Variable length arrays (VLAs) are translated to alloca() calls.
-      // For example, `int x[n+2]` is translated to `tmp = n + 2,
-      // x = alloca(tmp)`.
-      Obj *var = new_lvar(get_ident(ty->name), ty);
-      Token *tok = ty->name;
-      Node *expr = new_binary(ND_ASSIGN, new_vla_ptr(var, tok),
-                              new_alloca(new_var_node(ty->vla_size, tok)),
-                              tok);
-
-      cur = cur->next = new_unary(ND_EXPR_STMT, expr, tok);
-      continue;
-    }
-
-    Obj *var = new_lvar(get_ident(ty->name), ty);
-    if (attr && attr->align)
-      var->align = attr->align;
-
-    if (equal(tok, "=")) {
-      Node *expr = lvar_initializer(&tok, tok->next, var);
-      cur = cur->next = new_unary(ND_EXPR_STMT, expr, tok);
-    }
-
-    if (var->ty->size < 0)
-      error_tok(ty->name, "variable has incomplete type");
-    if (var->ty->kind == TY_VOID)
-      error_tok(ty->name, "variable declared void");
-  }
-
-  Node *node = new_node(ND_BLOCK, tok);
-  node->body = head.next;
-  *rest = tok->next;
-  return node;
-}
-
-static Token *skip_excess_element(Token *tok) {
-  if (equal(tok, "{")) {
-    tok = skip_excess_element(tok->next);
-    return skip(tok, "}");
-  }
-
-  assign(&tok, tok);
-  return tok;
-}
-
-// string-initializer = string-literal
-static void string_initializer(Token **rest, Token *tok, Initializer *init) {
-  if (init->is_flexible)
-    *init = *new_initializer(array_of(init->ty->base, tok->ty->array_len), false);
-
-  int len = MIN(init->ty->array_len, tok->ty->array_len);
-
-  switch (init->ty->base->size) {
-  case 1: {
-    char *str = tok->str;
-    for (int i = 0; i < len; i++)
-      init->children[i]->expr = new_num(str[i], tok);
-    break;
-  }
-  case 2: {
-    uint16_t *str = (uint16_t *)tok->str;
-    for (int i = 0; i < len; i++)
-      init->children[i]->expr = new_num(str[i], tok);
-    break;
-  }
-  case 4: {
-    uint32_t *str = (uint32_t *)tok->str;
-    for (int i = 0; i < len; i++)
-      init->children[i]->expr = new_num(str[i], tok);
-    break;
-  }
-  default:
-    unreachable();
-  }
-
-  *rest = tok->next;
-}
-
-// array-designator = "[" const-expr "]"
-//
-// C99 added the designated initializer to the language, which allows
-// programmers to move the "cursor" of an initializer to any element.
-// The syntax looks like this:
-//
-//   int x[10] = { 1, 2, [5]=3, 4, 5, 6, 7 };
-//
-// `[5]` moves the cursor to the 5th element, so the 5th element of x
-// is set to 3. Initialization then continues forward in order, so
-// 6th, 7th, 8th and 9th elements are initialized with 4, 5, 6 and 7,
-// respectively. Unspecified elements (in this case, 3rd and 4th
-// elements) are initialized with zero.
-//
-// Nesting is allowed, so the following initializer is valid:
-//
-//   int x[5][10] = { [5][8]=1, 2, 3 };
-//
-// It sets x[5][8], x[5][9] and x[6][0] to 1, 2 and 3, respectively.
-//
-// Use `.fieldname` to move the cursor for a struct initializer. E.g.
-//
-//   struct { int a, b, c; } x = { .c=5 };
-//
-// The above initializer sets x.c to 5.
-static void array_designator(Token **rest, Token *tok, Type *ty, int *begin, int *end) {
-  *begin = const_expr(&tok, tok->next);
-  if (*begin >= ty->array_len)
-    error_tok(tok, "array designator index exceeds array bounds");
-
-  if (equal(tok, "...")) {
-    *end = const_expr(&tok, tok->next);
-    if (*end >= ty->array_len)
-      error_tok(tok, "array designator index exceeds array bounds");
-    if (*end < *begin)
-      error_tok(tok, "array designator range [%d, %d] is empty", *begin, *end);
-  } else {
-    *end = *begin;
-  }
-
-  *rest = skip(tok, "]");
-}
-
-// struct-designator = "." ident
-static Member *struct_designator(Token **rest, Token *tok, Type *ty) {
-  Token *start = tok;
-  tok = skip(tok, ".");
-  if (tok->kind != TK_IDENT)
-    error_tok(tok, "expected a field designator");
-
-  for (Member *mem = ty->members; mem; mem = mem->next) {
-    // Anonymous struct member
-    if (mem->ty->kind == TY_STRUCT && !mem->name) {
-      if (get_struct_member(mem->ty, tok)) {
-        *rest = start;
-        return mem;
-      }
-      continue;
-    }
-
-    // Regular struct member
-    if (mem->name->len == tok->len && !strncmp(mem->name->loc, tok->loc, tok->len)) {
-      *rest = tok->next;
-      return mem;
-    }
-  }
-
-  error_tok(tok, "struct has no such member");
-}
-
-// designation = ("[" const-expr "]" | "." ident)* "="? initializer
-static void designation(Token **rest, Token *tok, Initializer *init) {
-  if (equal(tok, "[")) {
-    if (init->ty->kind != TY_ARRAY)
-      error_tok(tok, "array index in non-array initializer");
-
-    int begin, end;
-    array_designator(&tok, tok, init->ty, &begin, &end);
-
-    Token *tok2;
-    for (int i = begin; i <= end; i++)
-      designation(&tok2, tok, init->children[i]);
-    array_initializer2(rest, tok2, init, begin + 1);
-    return;
-  }
-
-  if (equal(tok, ".") && init->ty->kind == TY_STRUCT) {
-    Member *mem = struct_designator(&tok, tok, init->ty);
-    designation(&tok, tok, init->children[mem->idx]);
-    init->expr = NULL;
-    struct_initializer2(rest, tok, init, mem->next);
-    return;
-  }
-
-  if (equal(tok, ".") && init->ty->kind == TY_UNION) {
-    Member *mem = struct_designator(&tok, tok, init->ty);
-    init->mem = mem;
-    designation(rest, tok, init->children[mem->idx]);
-    return;
-  }
-
-  if (equal(tok, "."))
-    error_tok(tok, "field name not in struct or union initializer");
-
-  if (equal(tok, "="))
-    tok = tok->next;
-  initializer2(rest, tok, init);
-}
-
-// An array length can be omitted if an array has an initializer
-// (e.g. `int x[] = {1,2,3}`). If it's omitted, count the number
-// of initializer elements.
-static int count_array_init_elements(Token *tok, Type *ty) {
-  bool first = true;
-  Initializer *dummy = new_initializer(ty->base, true);
-
-  int i = 0, max = 0;
-
-  while (!consume_end(&tok, tok)) {
-    if (!first)
-      tok = skip(tok, ",");
-    first = false;
-
-    if (equal(tok, "[")) {
-      i = const_expr(&tok, tok->next);
-      if (equal(tok, "..."))
-        i = const_expr(&tok, tok->next);
-      tok = skip(tok, "]");
-      designation(&tok, tok, dummy);
-    } else {
-      initializer2(&tok, tok, dummy);
-    }
-
-    i++;
-    max = MAX(max, i);
-  }
-  return max;
-}
-
-// array-initializer1 = "{" initializer ("," initializer)* ","? "}"
-static void array_initializer1(Token **rest, Token *tok, Initializer *init) {
-  tok = skip(tok, "{");
-
-  if (init->is_flexible) {
-    int len = count_array_init_elements(tok, init->ty);
-    *init = *new_initializer(array_of(init->ty->base, len), false);
-  }
-
-  bool first = true;
-
-  if (init->is_flexible) {
-    int len = count_array_init_elements(tok, init->ty);
-    *init = *new_initializer(array_of(init->ty->base, len), false);
-  }
-
-  for (int i = 0; !consume_end(rest, tok); i++) {
-    if (!first)
-      tok = skip(tok, ",");
-    first = false;
-
-    if (equal(tok, "[")) {
-      int begin, end;
-      array_designator(&tok, tok, init->ty, &begin, &end);
-
-      Token *tok2;
-      for (int j = begin; j <= end; j++)
-        designation(&tok2, tok, init->children[j]);
-      tok = tok2;
-      i = end;
-      continue;
-    }
-
-    if (i < init->ty->array_len)
-      initializer2(&tok, tok, init->children[i]);
-    else
-      tok = skip_excess_element(tok);
-  }
-}
-
-// array-initializer2 = initializer ("," initializer)*
-static void array_initializer2(Token **rest, Token *tok, Initializer *init, int i) {
-  if (init->is_flexible) {
-    int len = count_array_init_elements(tok, init->ty);
-    *init = *new_initializer(array_of(init->ty->base, len), false);
-  }
-
-  for (; i < init->ty->array_len && !is_end(tok); i++) {
-    Token *start = tok;
-    if (i > 0)
-      tok = skip(tok, ",");
-
-    if (equal(tok, "[") || equal(tok, ".")) {
-      *rest = start;
-      return;
-    }
-
-    initializer2(&tok, tok, init->children[i]);
-  }
-  *rest = tok;
-}
-
-// struct-initializer1 = "{" initializer ("," initializer)* ","? "}"
-static void struct_initializer1(Token **rest, Token *tok, Initializer *init) {
-  tok = skip(tok, "{");
-
-  Member *mem = init->ty->members;
-  bool first = true;
-
-  while (!consume_end(rest, tok)) {
-    if (!first)
-      tok = skip(tok, ",");
-    first = false;
-
-    if (equal(tok, ".")) {
-      mem = struct_designator(&tok, tok, init->ty);
-      designation(&tok, tok, init->children[mem->idx]);
-      mem = mem->next;
-      continue;
-    }
-
-    if (mem) {
-      initializer2(&tok, tok, init->children[mem->idx]);
-      mem = mem->next;
-    } else {
-      tok = skip_excess_element(tok);
-    }
-  }
-}
-
-// struct-initializer2 = initializer ("," initializer)*
-static void struct_initializer2(Token **rest, Token *tok, Initializer *init, Member *mem) {
-  bool first = true;
-
-  for (; mem && !is_end(tok); mem = mem->next) {
-    Token *start = tok;
-
-    if (!first)
-      tok = skip(tok, ",");
-    first = false;
-
-    if (equal(tok, "[") || equal(tok, ".")) {
-      *rest = start;
-      return;
-    }
-
-    initializer2(&tok, tok, init->children[mem->idx]);
-  }
-  *rest = tok;
-}
-
-static void union_initializer(Token **rest, Token *tok, Initializer *init) {
-  // Unlike structs, union initializers take only one initializer,
-  // and that initializes the first union member by default.
-  // You can initialize other member using a designated initializer.
-  if (equal(tok, "{") && equal(tok->next, ".")) {
-    Member *mem = struct_designator(&tok, tok->next, init->ty);
-    init->mem = mem;
-    designation(&tok, tok, init->children[mem->idx]);
-    *rest = skip(tok, "}");
-    return;
-  }
-
-  init->mem = init->ty->members;
-
-  if (equal(tok, "{")) {
-    initializer2(&tok, tok->next, init->children[0]);
-    consume(&tok, tok, ",");
-    *rest = skip(tok, "}");
-  } else {
-    initializer2(rest, tok, init->children[0]);
-  }
-}
-
-// initializer = string-initializer | array-initializer
-//             | struct-initializer | union-initializer
-//             | assign
-static void initializer2(Token **rest, Token *tok, Initializer *init) {
-  if (init->ty->kind == TY_ARRAY && tok->kind == TK_STR) {
-    string_initializer(rest, tok, init);
-    return;
-  }
-
-  if (init->ty->kind == TY_ARRAY) {
-    if (equal(tok, "{"))
-      array_initializer1(rest, tok, init);
-    else
-      array_initializer2(rest, tok, init, 0);
-    return;
-  }
-
-  if (init->ty->kind == TY_STRUCT) {
-    if (equal(tok, "{")) {
-      struct_initializer1(rest, tok, init);
-      return;
-    }
-
-    // A struct can be initialized with another struct. E.g.
-    // `struct T x = y;` where y is a variable of type `struct T`.
-    // Handle that case first.
-    Node *expr = assign(rest, tok);
-    add_type(expr);
-    if (expr->ty->kind == TY_STRUCT) {
-      init->expr = expr;
-      return;
-    }
-
-    struct_initializer2(rest, tok, init, init->ty->members);
-    return;
-  }
-
-  if (init->ty->kind == TY_UNION) {
-    union_initializer(rest, tok, init);
-    return;
-  }
-
-  if (equal(tok, "{")) {
-    // An initializer for a scalar variable can be surrounded by
-    // braces. E.g. `int x = {3};`. Handle that case.
-    initializer2(&tok, tok->next, init);
-    *rest = skip(tok, "}");
-    return;
-  }
-
-  init->expr = assign(rest, tok);
-}
-
-static Type *copy_struct_type(Type *ty) {
-  ty = copy_type(ty);
-
-  Member head = {};
-  Member *cur = &head;
-  for (Member *mem = ty->members; mem; mem = mem->next) {
-    Member *m = calloc(1, sizeof(Member));
-    *m = *mem;
-    cur = cur->next = m;
-  }
-
-  ty->members = head.next;
-  return ty;
-}
-
-static Initializer *initializer(Token **rest, Token *tok, Type *ty, Type **new_ty) {
-  Initializer *init = new_initializer(ty, true);
-  initializer2(rest, tok, init);
-
-  if ((ty->kind == TY_STRUCT || ty->kind == TY_UNION) && ty->is_flexible) {
-    ty = copy_struct_type(ty);
-
-    Member *mem = ty->members;
-    while (mem->next)
-      mem = mem->next;
-    mem->ty = init->children[mem->idx]->ty;
-    ty->size += mem->ty->size;
-
-    *new_ty = ty;
-    return init;
-  }
-
-  *new_ty = init->ty;
-  return init;
-}
-
-static Node *init_desg_expr(InitDesg *desg, Token *tok) {
-  if (desg->var)
-    return new_var_node(desg->var, tok);
-
-  if (desg->member) {
-    Node *node = new_unary(ND_MEMBER, init_desg_expr(desg->next, tok), tok);
-    node->member = desg->member;
-    return node;
-  }
-
-  Node *lhs = init_desg_expr(desg->next, tok);
-  Node *rhs = new_num(desg->idx, tok);
-  return new_unary(ND_DEREF, new_add(lhs, rhs, tok), tok);
-}
-
-static Node *create_lvar_init(Initializer *init, Type *ty, InitDesg *desg, Token *tok) {
-  if (ty->kind == TY_ARRAY) {
-    Node *node = new_node(ND_NULL_EXPR, tok);
-    for (int i = 0; i < ty->array_len; i++) {
-      InitDesg desg2 = {desg, i};
-      Node *rhs = create_lvar_init(init->children[i], ty->base, &desg2, tok);
-      node = new_binary(ND_COMMA, node, rhs, tok);
-    }
-    return node;
-  }
-
-  if (ty->kind == TY_STRUCT && !init->expr) {
-    Node *node = new_node(ND_NULL_EXPR, tok);
-
-    for (Member *mem = ty->members; mem; mem = mem->next) {
-      InitDesg desg2 = {desg, 0, mem};
-      Node *rhs = create_lvar_init(init->children[mem->idx], mem->ty, &desg2, tok);
-      node = new_binary(ND_COMMA, node, rhs, tok);
-    }
-    return node;
-  }
-
-  if (ty->kind == TY_UNION) {
-    Member *mem = init->mem ? init->mem : ty->members;
-    InitDesg desg2 = {desg, 0, mem};
-    return create_lvar_init(init->children[mem->idx], mem->ty, &desg2, tok);
-  }
-
-  if (!init->expr)
-    return new_node(ND_NULL_EXPR, tok);
-
-  Node *lhs = init_desg_expr(desg, tok);
-  return new_binary(ND_ASSIGN, lhs, init->expr, tok);
-}
-
-// A variable definition with an initializer is a shorthand notation
-// for a variable definition followed by assignments. This function
-// generates assignment expressions for an initializer. For example,
-// `int x[2][2] = {{6, 7}, {8, 9}}` is converted to the following
-// expressions:
-//
-//   x[0][0] = 6;
-//   x[0][1] = 7;
-//   x[1][0] = 8;
-//   x[1][1] = 9;
-static Node *lvar_initializer(Token **rest, Token *tok, Obj *var) {
-  Initializer *init = initializer(rest, tok, var->ty, &var->ty);
-  InitDesg desg = {NULL, 0, NULL, var};
-
-  // If a partial initializer list is given, the standard requires
-  // that unspecified elements are set to 0. Here, we simply
-  // zero-initialize the entire memory region of a variable before
-  // initializing it with user-supplied values.
-  Node *lhs = new_node(ND_MEMZERO, tok);
-  lhs->var = var;
-
-  Node *rhs = create_lvar_init(init, var->ty, &desg, tok);
-  return new_binary(ND_COMMA, lhs, rhs, tok);
-}
-
-static uint64_t read_buf(char *buf, int sz) {
-  if (sz == 1)
-    return *buf;
-  if (sz == 2)
-    return *(uint16_t *)buf;
-  if (sz == 4)
-    return *(uint32_t *)buf;
-  if (sz == 8)
-    return *(uint64_t *)buf;
-  unreachable();
-}
-
-static void write_buf(char *buf, uint64_t val, int sz) {
-  if (sz == 1)
-    *buf = val;
-  else if (sz == 2)
-    *(uint16_t *)buf = val;
-  else if (sz == 4)
-    *(uint32_t *)buf = val;
-  else if (sz == 8)
-    *(uint64_t *)buf = val;
-  else
-    unreachable();
-}
-
-static Relocation *
-write_gvar_data(Relocation *cur, Initializer *init, Type *ty, char *buf, int offset) {
-  if (ty->kind == TY_ARRAY) {
-    int sz = ty->base->size;
-    for (int i = 0; i < ty->array_len; i++)
-      cur = write_gvar_data(cur, init->children[i], ty->base, buf, offset + sz * i);
-    return cur;
-  }
-
-  if (ty->kind == TY_STRUCT) {
-    for (Member *mem = ty->members; mem; mem = mem->next) {
-      if (mem->is_bitfield) {
-        Node *expr = init->children[mem->idx]->expr;
-        if (!expr)
-          break;
-
-        char *loc = buf + offset + mem->offset;
-        uint64_t oldval = read_buf(loc, mem->ty->size);
-        uint64_t newval = eval(expr);
-        uint64_t mask = (1L << mem->bit_width) - 1;
-        uint64_t combined = oldval | ((newval & mask) << mem->bit_offset);
-        write_buf(loc, combined, mem->ty->size);
-      } else {
-        cur = write_gvar_data(cur, init->children[mem->idx], mem->ty, buf,
-                              offset + mem->offset);
-      }
-    }
-    return cur;
-  }
-
-  if (ty->kind == TY_UNION) {
-    if (!init->mem)
-      return cur;
-    return write_gvar_data(cur, init->children[init->mem->idx],
-                           init->mem->ty, buf, offset);
-  }
-
-  if (!init->expr)
-    return cur;
-
-  if (ty->kind == TY_FLOAT) {
-    *(float *)(buf + offset) = eval_double(init->expr);
-    return cur;
-  }
-
-  if (ty->kind == TY_DOUBLE) {
-    *(double *)(buf + offset) = eval_double(init->expr);
-    return cur;
-  }
-
-  char **label = NULL;
-  uint64_t val = eval2(init->expr, &label);
-
-  if (!label) {
-    write_buf(buf + offset, val, ty->size);
-    return cur;
-  }
-
-  Relocation *rel = calloc(1, sizeof(Relocation));
-  rel->offset = offset;
-  rel->label = label;
-  rel->addend = val;
-  cur->next = rel;
-  return cur->next;
-}
-
-// Initializers for global variables are evaluated at compile-time and
-// embedded to .data section. This function serializes Initializer
-// objects to a flat byte array. It is a compile error if an
-// initializer list contains a non-constant expression.
-static void gvar_initializer(Token **rest, Token *tok, Obj *var) {
-  Initializer *init = initializer(rest, tok, var->ty, &var->ty);
-
-  Relocation head = {};
-  char *buf = calloc(1, var->ty->size);
-  write_gvar_data(&head, init, var->ty, buf, 0);
-  var->init_data = buf;
-  var->rel = head.next;
-}
-
-// Returns true if a given token represents a type.
-static bool is_typename(Token *tok) {
-  static HashMap map;
-
-  if (map.capacity == 0) {
-    static char *kw[] = {
-      "void", "_Bool", "char", "short", "int", "long", "struct", "union",
-      "typedef", "enum", "static", "extern", "_Alignas", "signed", "unsigned",
-      "const", "volatile", "auto", "register", "restrict", "__restrict",
-      "__restrict__", "_Noreturn", "float", "double", "typeof", "inline",
-      "_Thread_local", "__thread", "_Atomic",
-    };
-
-    for (int i = 0; i < sizeof(kw) / sizeof(*kw); i++)
-      hashmap_put(&map, kw[i], (void *)1);
-  }
-
-  return hashmap_get2(&map, tok->loc, tok->len) || find_typedef(tok);
-}
-
-// asm-stmt = "asm" ("volatile" | "inline")* "(" string-literal ")"
-static Node *asm_stmt(Token **rest, Token *tok) {
-  Node *node = new_node(ND_ASM, tok);
-  tok = tok->next;
-
-  while (equal(tok, "volatile") || equal(tok, "inline"))
-    tok = tok->next;
-
-  tok = skip(tok, "(");
-  if (tok->kind != TK_STR || tok->ty->base->kind != TY_CHAR)
-    error_tok(tok, "expected string literal");
-  node->asm_str = tok->str;
-  *rest = skip(tok->next, ")");
-  return node;
-}
-
-// stmt = "return" expr? ";"
-//      | "if" "(" expr ")" stmt ("else" stmt)?
-//      | "switch" "(" expr ")" stmt
-//      | "case" const-expr ("..." const-expr)? ":" stmt
-//      | "default" ":" stmt
-//      | "for" "(" expr-stmt expr? ";" expr? ")" stmt
-//      | "while" "(" expr ")" stmt
-//      | "do" stmt "while" "(" expr ")" ";"
-//      | "asm" asm-stmt
-//      | "goto" (ident | "*" expr) ";"
-//      | "break" ";"
-//      | "continue" ";"
-//      | ident ":" stmt
-//      | "{" compound-stmt
-//      | expr-stmt
-static Node *stmt(Token **rest, Token *tok) {
-  if (equal(tok, "return")) {
-    Node *node = new_node(ND_RETURN, tok);
-    if (consume(rest, tok->next, ";"))
-      return node;
-
-    Node *exp = expr(&tok, tok->next);
-    *rest = skip(tok, ";");
-
-    add_type(exp);
-    Type *ty = current_fn->ty->return_ty;
-    if (ty->kind != TY_STRUCT && ty->kind != TY_UNION)
-      exp = new_cast(exp, current_fn->ty->return_ty);
-
-    node->lhs = exp;
-    return node;
-  }
-
-  if (equal(tok, "if")) {
-    Node *node = new_node(ND_IF, tok);
-    tok = skip(tok->next, "(");
-    node->cond = expr(&tok, tok);
-    tok = skip(tok, ")");
-    node->then = stmt(&tok, tok);
-    if (equal(tok, "else"))
-      node->els = stmt(&tok, tok->next);
-    *rest = tok;
-    return node;
-  }
-
-  if (equal(tok, "switch")) {
-    Node *node = new_node(ND_SWITCH, tok);
-    tok = skip(tok->next, "(");
-    node->cond = expr(&tok, tok);
-    tok = skip(tok, ")");
-
-    Node *sw = current_switch;
-    current_switch = node;
-
-    char *brk = brk_label;
-    brk_label = node->brk_label = new_unique_name();
-
-    node->then = stmt(rest, tok);
-
-    current_switch = sw;
-    brk_label = brk;
-    return node;
-  }
-
-  if (equal(tok, "case")) {
-    if (!current_switch)
-      error_tok(tok, "stray case");
-
-    Node *node = new_node(ND_CASE, tok);
-    int begin = const_expr(&tok, tok->next);
-    int end;
-
-    if (equal(tok, "...")) {
-      // [GNU] Case ranges, e.g. "case 1 ... 5:"
-      end = const_expr(&tok, tok->next);
-      if (end < begin)
-        error_tok(tok, "empty case range specified");
-    } else {
-      end = begin;
-    }
-
-    tok = skip(tok, ":");
-    node->label = new_unique_name();
-    node->lhs = stmt(rest, tok);
-    node->begin = begin;
-    node->end = end;
-    node->case_next = current_switch->case_next;
-    current_switch->case_next = node;
-    return node;
-  }
-
-  if (equal(tok, "default")) {
-    if (!current_switch)
-      error_tok(tok, "stray default");
-
-    Node *node = new_node(ND_CASE, tok);
-    tok = skip(tok->next, ":");
-    node->label = new_unique_name();
-    node->lhs = stmt(rest, tok);
-    current_switch->default_case = node;
-    return node;
-  }
-
-  if (equal(tok, "for")) {
-    Node *node = new_node(ND_FOR, tok);
-    tok = skip(tok->next, "(");
-
-    enter_scope();
-
-    char *brk = brk_label;
-    char *cont = cont_label;
-    brk_label = node->brk_label = new_unique_name();
-    cont_label = node->cont_label = new_unique_name();
-
-    if (is_typename(tok)) {
-      Type *basety = declspec(&tok, tok, NULL);
-      node->init = declaration(&tok, tok, basety, NULL);
-    } else {
-      node->init = expr_stmt(&tok, tok);
-    }
-
-    if (!equal(tok, ";"))
-      node->cond = expr(&tok, tok);
-    tok = skip(tok, ";");
-
-    if (!equal(tok, ")"))
-      node->inc = expr(&tok, tok);
-    tok = skip(tok, ")");
-
-    node->then = stmt(rest, tok);
-
-    leave_scope();
-    brk_label = brk;
-    cont_label = cont;
-    return node;
-  }
-
-  if (equal(tok, "while")) {
-    Node *node = new_node(ND_FOR, tok);
-    tok = skip(tok->next, "(");
-    node->cond = expr(&tok, tok);
-    tok = skip(tok, ")");
-
-    char *brk = brk_label;
-    char *cont = cont_label;
-    brk_label = node->brk_label = new_unique_name();
-    cont_label = node->cont_label = new_unique_name();
-
-    node->then = stmt(rest, tok);
-
-    brk_label = brk;
-    cont_label = cont;
-    return node;
-  }
-
-  if (equal(tok, "do")) {
-    Node *node = new_node(ND_DO, tok);
-
-    char *brk = brk_label;
-    char *cont = cont_label;
-    brk_label = node->brk_label = new_unique_name();
-    cont_label = node->cont_label = new_unique_name();
-
-    node->then = stmt(&tok, tok->next);
-
-    brk_label = brk;
-    cont_label = cont;
-
-    tok = skip(tok, "while");
-    tok = skip(tok, "(");
-    node->cond = expr(&tok, tok);
-    tok = skip(tok, ")");
-    *rest = skip(tok, ";");
-    return node;
-  }
-
-  if (equal(tok, "asm"))
-    return asm_stmt(rest, tok);
-
-  if (equal(tok, "goto")) {
-    if (equal(tok->next, "*")) {
-      // [GNU] `goto *ptr` jumps to the address specified by `ptr`.
-      Node *node = new_node(ND_GOTO_EXPR, tok);
-      node->lhs = expr(&tok, tok->next->next);
-      *rest = skip(tok, ";");
-      return node;
-    }
-
-    Node *node = new_node(ND_GOTO, tok);
-    node->label = get_ident(tok->next);
-    node->goto_next = gotos;
-    gotos = node;
-    *rest = skip(tok->next->next, ";");
-    return node;
-  }
-
-  if (equal(tok, "break")) {
-    if (!brk_label)
-      error_tok(tok, "stray break");
-    Node *node = new_node(ND_GOTO, tok);
-    node->unique_label = brk_label;
-    *rest = skip(tok->next, ";");
-    return node;
-  }
-
-  if (equal(tok, "continue")) {
-    if (!cont_label)
-      error_tok(tok, "stray continue");
-    Node *node = new_node(ND_GOTO, tok);
-    node->unique_label = cont_label;
-    *rest = skip(tok->next, ";");
-    return node;
-  }
-
-  if (tok->kind == TK_IDENT && equal(tok->next, ":")) {
-    Node *node = new_node(ND_LABEL, tok);
-    node->label = strndup(tok->loc, tok->len);
-    node->unique_label = new_unique_name();
-    node->lhs = stmt(rest, tok->next->next);
-    node->goto_next = labels;
-    labels = node;
-    return node;
-  }
-
-  if (equal(tok, "{"))
-    return compound_stmt(rest, tok->next);
-
-  return expr_stmt(rest, tok);
-}
-
-// compound-stmt = (typedef | declaration | stmt)* "}"
-static Node *compound_stmt(Token **rest, Token *tok) {
-  Node *node = new_node(ND_BLOCK, tok);
-  Node head = {};
-  Node *cur = &head;
-
-  enter_scope();
-
-  while (!equal(tok, "}")) {
-    if (is_typename(tok) && !equal(tok->next, ":")) {
-      VarAttr attr = {};
-      Type *basety = declspec(&tok, tok, &attr);
-
-      if (attr.is_typedef) {
-        tok = parse_typedef(tok, basety);
-        continue;
-      }
-
-      if (is_function(tok)) {
-        tok = function(tok, basety, &attr);
-        continue;
-      }
-
-      if (attr.is_extern) {
-        tok = global_variable(tok, basety, &attr);
-        continue;
-      }
-
-      cur = cur->next = declaration(&tok, tok, basety, &attr);
-    } else {
-      cur = cur->next = stmt(&tok, tok);
-    }
-    add_type(cur);
-  }
-
-  leave_scope();
-
-  node->body = head.next;
-  *rest = tok->next;
-  return node;
-}
-
-// expr-stmt = expr? ";"
-static Node *expr_stmt(Token **rest, Token *tok) {
-  if (equal(tok, ";")) {
-    *rest = tok->next;
-    return new_node(ND_BLOCK, tok);
-  }
-
-  Node *node = new_node(ND_EXPR_STMT, tok);
-  node->lhs = expr(&tok, tok);
-  *rest = skip(tok, ";");
-  return node;
-}
-
-// expr = assign ("," expr)?
-static Node *expr(Token **rest, Token *tok) {
-  Node *node = assign(&tok, tok);
-
-  if (equal(tok, ","))
-    return new_binary(ND_COMMA, node, expr(rest, tok->next), tok);
-
-  *rest = tok;
-  return node;
-}
-
-static int64_t eval(Node *node) {
-  return eval2(node, NULL);
-}
-
-// Evaluate a given node as a constant expression.
-//
-// A constant expression is either just a number or ptr+n where ptr
-// is a pointer to a global variable and n is a postiive/negative
-// number. The latter form is accepted only as an initialization
-// expression for a global variable.
-static int64_t eval2(Node *node, char ***label) {
-  add_type(node);
-
-  if (is_flonum(node->ty))
-    return eval_double(node);
-
-  switch (node->kind) {
-  case ND_ADD:
-    return eval2(node->lhs, label) + eval(node->rhs);
-  case ND_SUB:
-    return eval2(node->lhs, label) - eval(node->rhs);
-  case ND_MUL:
-    return eval(node->lhs) * eval(node->rhs);
-  case ND_DIV:
-    if (node->ty->is_unsigned)
-      return (uint64_t)eval(node->lhs) / eval(node->rhs);
-    return eval(node->lhs) / eval(node->rhs);
-  case ND_NEG:
-    return -eval(node->lhs);
-  case ND_MOD:
-    if (node->ty->is_unsigned)
-      return (uint64_t)eval(node->lhs) % eval(node->rhs);
-    return eval(node->lhs) % eval(node->rhs);
-  case ND_BITAND:
-    return eval(node->lhs) & eval(node->rhs);
-  case ND_BITOR:
-    return eval(node->lhs) | eval(node->rhs);
-  case ND_BITXOR:
-    return eval(node->lhs) ^ eval(node->rhs);
-  case ND_SHL:
-    return eval(node->lhs) << eval(node->rhs);
-  case ND_SHR:
-    if (node->ty->is_unsigned && node->ty->size == 8)
-      return (uint64_t)eval(node->lhs) >> eval(node->rhs);
-    return eval(node->lhs) >> eval(node->rhs);
-  case ND_EQ:
-    return eval(node->lhs) == eval(node->rhs);
-  case ND_NE:
-    return eval(node->lhs) != eval(node->rhs);
-  case ND_LT:
-    if (node->lhs->ty->is_unsigned)
-      return (uint64_t)eval(node->lhs) < eval(node->rhs);
-    return eval(node->lhs) < eval(node->rhs);
-  case ND_LE:
-    if (node->lhs->ty->is_unsigned)
-      return (uint64_t)eval(node->lhs) <= eval(node->rhs);
-    return eval(node->lhs) <= eval(node->rhs);
-  case ND_COND:
-    return eval(node->cond) ? eval2(node->then, label) : eval2(node->els, label);
-  case ND_COMMA:
-    return eval2(node->rhs, label);
-  case ND_NOT:
-    return !eval(node->lhs);
-  case ND_BITNOT:
-    return ~eval(node->lhs);
-  case ND_LOGAND:
-    return eval(node->lhs) && eval(node->rhs);
-  case ND_LOGOR:
-    return eval(node->lhs) || eval(node->rhs);
-  case ND_CAST: {
-    int64_t val = eval2(node->lhs, label);
-    if (is_integer(node->ty)) {
-      switch (node->ty->size) {
-      case 1: return node->ty->is_unsigned ? (uint8_t)val : (int8_t)val;
-      case 2: return node->ty->is_unsigned ? (uint16_t)val : (int16_t)val;
-      case 4: return node->ty->is_unsigned ? (uint32_t)val : (int32_t)val;
-      }
-    }
-    return val;
-  }
-  case ND_ADDR:
-    return eval_rval(node->lhs, label);
-  case ND_LABEL_VAL:
-    *label = &node->unique_label;
-    return 0;
-  case ND_MEMBER:
-    if (!label)
-      error_tok(node->tok, "not a compile-time constant");
-    if (node->ty->kind != TY_ARRAY)
-      error_tok(node->tok, "invalid initializer");
-    return eval_rval(node->lhs, label) + node->member->offset;
-  case ND_VAR:
-    if (!label)
-      error_tok(node->tok, "not a compile-time constant");
-    if (node->var->ty->kind != TY_ARRAY && node->var->ty->kind != TY_FUNC)
-      error_tok(node->tok, "invalid initializer");
-    *label = &node->var->name;
-    return 0;
-  case ND_NUM:
-    return node->val;
-  }
-
-  error_tok(node->tok, "not a compile-time constant");
-}
-
-static int64_t eval_rval(Node *node, char ***label) {
-  switch (node->kind) {
-  case ND_VAR:
-    if (node->var->is_local)
-      error_tok(node->tok, "not a compile-time constant");
-    *label = &node->var->name;
-    return 0;
-  case ND_DEREF:
-    return eval2(node->lhs, label);
-  case ND_MEMBER:
-    return eval_rval(node->lhs, label) + node->member->offset;
-  }
-
-  error_tok(node->tok, "invalid initializer");
-}
-
-static bool is_const_expr(Node *node) {
-  add_type(node);
-
-  switch (node->kind) {
-  case ND_ADD:
-  case ND_SUB:
-  case ND_MUL:
-  case ND_DIV:
-  case ND_BITAND:
-  case ND_BITOR:
-  case ND_BITXOR:
-  case ND_SHL:
-  case ND_SHR:
-  case ND_EQ:
-  case ND_NE:
-  case ND_LT:
-  case ND_LE:
-  case ND_LOGAND:
-  case ND_LOGOR:
-    return is_const_expr(node->lhs) && is_const_expr(node->rhs);
-  case ND_COND:
-    if (!is_const_expr(node->cond))
-      return false;
-    return is_const_expr(eval(node->cond) ? node->then : node->els);
-  case ND_COMMA:
-    return is_const_expr(node->rhs);
-  case ND_NEG:
-  case ND_NOT:
-  case ND_BITNOT:
-  case ND_CAST:
-    return is_const_expr(node->lhs);
-  case ND_NUM:
-    return true;
-  }
-
-  return false;
-}
-
-int64_t const_expr(Token **rest, Token *tok) {
-  Node *node = conditional(rest, tok);
-  return eval(node);
-}
-
-static double eval_double(Node *node) {
-  add_type(node);
-
-  if (is_integer(node->ty)) {
-    if (node->ty->is_unsigned)
-      return (unsigned long)eval(node);
-    return eval(node);
-  }
-
-  switch (node->kind) {
-  case ND_ADD:
-    return eval_double(node->lhs) + eval_double(node->rhs);
-  case ND_SUB:
-    return eval_double(node->lhs) - eval_double(node->rhs);
-  case ND_MUL:
-    return eval_double(node->lhs) * eval_double(node->rhs);
-  case ND_DIV:
-    return eval_double(node->lhs) / eval_double(node->rhs);
-  case ND_NEG:
-    return -eval_double(node->lhs);
-  case ND_COND:
-    return eval_double(node->cond) ? eval_double(node->then) : eval_double(node->els);
-  case ND_COMMA:
-    return eval_double(node->rhs);
-  case ND_CAST:
-    if (is_flonum(node->lhs->ty))
-      return eval_double(node->lhs);
-    return eval(node->lhs);
-  case ND_NUM:
-    return node->fval;
-  }
-
-  error_tok(node->tok, "not a compile-time constant");
-}
-
-// Convert op= operators to expressions containing an assignment.
-//
-// In general, `A op= C` is converted to ``tmp = &A, *tmp = *tmp op B`.
-// However, if a given expression is of form `A.x op= C`, the input is
-// converted to `tmp = &A, (*tmp).x = (*tmp).x op C` to handle assignments
-// to bitfields.
-static Node *to_assign(Node *binary) {
-  add_type(binary->lhs);
-  add_type(binary->rhs);
-  Token *tok = binary->tok;
-
-  // Convert `A.x op= C` to `tmp = &A, (*tmp).x = (*tmp).x op C`.
-  if (binary->lhs->kind == ND_MEMBER) {
-    Obj *var = new_lvar("", pointer_to(binary->lhs->lhs->ty));
-
-    Node *expr1 = new_binary(ND_ASSIGN, new_var_node(var, tok),
-                             new_unary(ND_ADDR, binary->lhs->lhs, tok), tok);
-
-    Node *expr2 = new_unary(ND_MEMBER,
-                            new_unary(ND_DEREF, new_var_node(var, tok), tok),
-                            tok);
-    expr2->member = binary->lhs->member;
-
-    Node *expr3 = new_unary(ND_MEMBER,
-                            new_unary(ND_DEREF, new_var_node(var, tok), tok),
-                            tok);
-    expr3->member = binary->lhs->member;
-
-    Node *expr4 = new_binary(ND_ASSIGN, expr2,
-                             new_binary(binary->kind, expr3, binary->rhs, tok),
-                             tok);
-
-    return new_binary(ND_COMMA, expr1, expr4, tok);
-  }
-
-  // If A is an atomic type, Convert `A op= B` to
-  //
-  // ({
-  //   T1 *addr = &A; T2 val = (B); T1 old = *addr; T1 new;
-  //   do {
-  //    new = old op val;
-  //   } while (!atomic_compare_exchange_strong(addr, &old, new));
-  //   new;
-  // })
-  if (binary->lhs->ty->is_atomic) {
-    Node head = {};
-    Node *cur = &head;
-
-    Obj *addr = new_lvar("", pointer_to(binary->lhs->ty));
-    Obj *val = new_lvar("", binary->rhs->ty);
-    Obj *old = new_lvar("", binary->lhs->ty);
-    Obj *new = new_lvar("", binary->lhs->ty);
-
-    cur = cur->next =
-      new_unary(ND_EXPR_STMT,
-                new_binary(ND_ASSIGN, new_var_node(addr, tok),
-                           new_unary(ND_ADDR, binary->lhs, tok), tok),
-                tok);
-
-    cur = cur->next =
-      new_unary(ND_EXPR_STMT,
-                new_binary(ND_ASSIGN, new_var_node(val, tok), binary->rhs, tok),
-                tok);
-
-    cur = cur->next =
-      new_unary(ND_EXPR_STMT,
-                new_binary(ND_ASSIGN, new_var_node(old, tok),
-                           new_unary(ND_DEREF, new_var_node(addr, tok), tok), tok),
-                tok);
-
-    Node *loop = new_node(ND_DO, tok);
-    loop->brk_label = new_unique_name();
-    loop->cont_label = new_unique_name();
-
-    Node *body = new_binary(ND_ASSIGN,
-                            new_var_node(new, tok),
-                            new_binary(binary->kind, new_var_node(old, tok),
-                                       new_var_node(val, tok), tok),
-                            tok);
-
-    loop->then = new_node(ND_BLOCK, tok);
-    loop->then->body = new_unary(ND_EXPR_STMT, body, tok);
-
-    Node *cas = new_node(ND_CAS, tok);
-    cas->cas_addr = new_var_node(addr, tok);
-    cas->cas_old = new_unary(ND_ADDR, new_var_node(old, tok), tok);
-    cas->cas_new = new_var_node(new, tok);
-    loop->cond = new_unary(ND_NOT, cas, tok);
-
-    cur = cur->next = loop;
-    cur = cur->next = new_unary(ND_EXPR_STMT, new_var_node(new, tok), tok);
-
-    Node *node = new_node(ND_STMT_EXPR, tok);
-    node->body = head.next;
-    return node;
-  }
-
-  // Convert `A op= B` to ``tmp = &A, *tmp = *tmp op B`.
-  Obj *var = new_lvar("", pointer_to(binary->lhs->ty));
-
-  Node *expr1 = new_binary(ND_ASSIGN, new_var_node(var, tok),
-                           new_unary(ND_ADDR, binary->lhs, tok), tok);
-
-  Node *expr2 =
-    new_binary(ND_ASSIGN,
-               new_unary(ND_DEREF, new_var_node(var, tok), tok),
-               new_binary(binary->kind,
-                          new_unary(ND_DEREF, new_var_node(var, tok), tok),
-                          binary->rhs,
-                          tok),
-               tok);
-
-  return new_binary(ND_COMMA, expr1, expr2, tok);
-}
-
-// assign    = conditional (assign-op assign)?
-// assign-op = "=" | "+=" | "-=" | "*=" | "/=" | "%=" | "&=" | "|=" | "^="
-//           | "<<=" | ">>="
-static Node *assign(Token **rest, Token *tok) {
-  Node *node = conditional(&tok, tok);
-
-  if (equal(tok, "="))
-    return new_binary(ND_ASSIGN, node, assign(rest, tok->next), tok);
-
-  if (equal(tok, "+="))
-    return to_assign(new_add(node, assign(rest, tok->next), tok));
-
-  if (equal(tok, "-="))
-    return to_assign(new_sub(node, assign(rest, tok->next), tok));
-
-  if (equal(tok, "*="))
-    return to_assign(new_binary(ND_MUL, node, assign(rest, tok->next), tok));
-
-  if (equal(tok, "/="))
-    return to_assign(new_binary(ND_DIV, node, assign(rest, tok->next), tok));
-
-  if (equal(tok, "%="))
-    return to_assign(new_binary(ND_MOD, node, assign(rest, tok->next), tok));
-
-  if (equal(tok, "&="))
-    return to_assign(new_binary(ND_BITAND, node, assign(rest, tok->next), tok));
-
-  if (equal(tok, "|="))
-    return to_assign(new_binary(ND_BITOR, node, assign(rest, tok->next), tok));
-
-  if (equal(tok, "^="))
-    return to_assign(new_binary(ND_BITXOR, node, assign(rest, tok->next), tok));
-
-  if (equal(tok, "<<="))
-    return to_assign(new_binary(ND_SHL, node, assign(rest, tok->next), tok));
-
-  if (equal(tok, ">>="))
-    return to_assign(new_binary(ND_SHR, node, assign(rest, tok->next), tok));
-
-  *rest = tok;
-  return node;
-}
-
-// conditional = logor ("?" expr? ":" conditional)?
-static Node *conditional(Token **rest, Token *tok) {
-  Node *cond = logor(&tok, tok);
-
-  if (!equal(tok, "?")) {
-    *rest = tok;
-    return cond;
-  }
-
-  if (equal(tok->next, ":")) {
-    // [GNU] Compile `a ?: b` as `tmp = a, tmp ? tmp : b`.
-    add_type(cond);
-    Obj *var = new_lvar("", cond->ty);
-    Node *lhs = new_binary(ND_ASSIGN, new_var_node(var, tok), cond, tok);
-    Node *rhs = new_node(ND_COND, tok);
-    rhs->cond = new_var_node(var, tok);
-    rhs->then = new_var_node(var, tok);
-    rhs->els = conditional(rest, tok->next->next);
-    return new_binary(ND_COMMA, lhs, rhs, tok);
-  }
-
-  Node *node = new_node(ND_COND, tok);
-  node->cond = cond;
-  node->then = expr(&tok, tok->next);
-  tok = skip(tok, ":");
-  node->els = conditional(rest, tok);
-  return node;
-}
-
-// logor = logand ("||" logand)*
-static Node *logor(Token **rest, Token *tok) {
-  Node *node = logand(&tok, tok);
-  while (equal(tok, "||")) {
-    Token *start = tok;
-    node = new_binary(ND_LOGOR, node, logand(&tok, tok->next), start);
-  }
-  *rest = tok;
-  return node;
-}
-
-// logand = bitor ("&&" bitor)*
-static Node *logand(Token **rest, Token *tok) {
-  Node *node = bitor(&tok, tok);
-  while (equal(tok, "&&")) {
-    Token *start = tok;
-    node = new_binary(ND_LOGAND, node, bitor(&tok, tok->next), start);
-  }
-  *rest = tok;
-  return node;
-}
-
-// bitor = bitxor ("|" bitxor)*
-static Node *bitor(Token **rest, Token *tok) {
-  Node *node = bitxor(&tok, tok);
-  while (equal(tok, "|")) {
-    Token *start = tok;
-    node = new_binary(ND_BITOR, node, bitxor(&tok, tok->next), start);
-  }
-  *rest = tok;
-  return node;
-}
-
-// bitxor = bitand ("^" bitand)*
-static Node *bitxor(Token **rest, Token *tok) {
-  Node *node = bitand(&tok, tok);
-  while (equal(tok, "^")) {
-    Token *start = tok;
-    node = new_binary(ND_BITXOR, node, bitand(&tok, tok->next), start);
-  }
-  *rest = tok;
-  return node;
-}
-
-// bitand = equality ("&" equality)*
-static Node *bitand(Token **rest, Token *tok) {
-  Node *node = equality(&tok, tok);
-  while (equal(tok, "&")) {
-    Token *start = tok;
-    node = new_binary(ND_BITAND, node, equality(&tok, tok->next), start);
-  }
-  *rest = tok;
-  return node;
-}
-
-// equality = relational ("==" relational | "!=" relational)*
-static Node *equality(Token **rest, Token *tok) {
-  Node *node = relational(&tok, tok);
-
-  for (;;) {
-    Token *start = tok;
-
-    if (equal(tok, "==")) {
-      node = new_binary(ND_EQ, node, relational(&tok, tok->next), start);
-      continue;
-    }
-
-    if (equal(tok, "!=")) {
-      node = new_binary(ND_NE, node, relational(&tok, tok->next), start);
-      continue;
-    }
-
-    *rest = tok;
-    return node;
-  }
-}
-
-// relational = shift ("<" shift | "<=" shift | ">" shift | ">=" shift)*
-static Node *relational(Token **rest, Token *tok) {
-  Node *node = shift(&tok, tok);
-
-  for (;;) {
-    Token *start = tok;
-
-    if (equal(tok, "<")) {
-      node = new_binary(ND_LT, node, shift(&tok, tok->next), start);
-      continue;
-    }
-
-    if (equal(tok, "<=")) {
-      node = new_binary(ND_LE, node, shift(&tok, tok->next), start);
-      continue;
-    }
-
-    if (equal(tok, ">")) {
-      node = new_binary(ND_LT, shift(&tok, tok->next), node, start);
-      continue;
-    }
-
-    if (equal(tok, ">=")) {
-      node = new_binary(ND_LE, shift(&tok, tok->next), node, start);
-      continue;
-    }
-
-    *rest = tok;
-    return node;
-  }
-}
-
-// shift = add ("<<" add | ">>" add)*
-static Node *shift(Token **rest, Token *tok) {
-  Node *node = add(&tok, tok);
-
-  for (;;) {
-    Token *start = tok;
-
-    if (equal(tok, "<<")) {
-      node = new_binary(ND_SHL, node, add(&tok, tok->next), start);
-      continue;
-    }
-
-    if (equal(tok, ">>")) {
-      node = new_binary(ND_SHR, node, add(&tok, tok->next), start);
-      continue;
-    }
-
-    *rest = tok;
-    return node;
-  }
-}
-
-// In C, `+` operator is overloaded to perform the pointer arithmetic.
-// If p is a pointer, p+n adds not n but sizeof(*p)*n to the value of p,
-// so that p+n points to the location n elements (not bytes) ahead of p.
-// In other words, we need to scale an integer value before adding to a
-// pointer value. This function takes care of the scaling.
-static Node *new_add(Node *lhs, Node *rhs, Token *tok) {
-  add_type(lhs);
-  add_type(rhs);
-
-  // num + num
-  if (is_numeric(lhs->ty) && is_numeric(rhs->ty))
-    return new_binary(ND_ADD, lhs, rhs, tok);
-
-  if (lhs->ty->base && rhs->ty->base)
-    error_tok(tok, "invalid operands");
-
-  // Canonicalize `num + ptr` to `ptr + num`.
-  if (!lhs->ty->base && rhs->ty->base) {
-    Node *tmp = lhs;
-    lhs = rhs;
-    rhs = tmp;
-  }
-
-  // VLA + num
-  if (lhs->ty->base->kind == TY_VLA) {
-    rhs = new_binary(ND_MUL, rhs, new_var_node(lhs->ty->base->vla_size, tok), tok);
-    return new_binary(ND_ADD, lhs, rhs, tok);
-  }
-
-  // ptr + num
-  rhs = new_binary(ND_MUL, rhs, new_long(lhs->ty->base->size, tok), tok);
-  return new_binary(ND_ADD, lhs, rhs, tok);
-}
-
-// Like `+`, `-` is overloaded for the pointer type.
-static Node *new_sub(Node *lhs, Node *rhs, Token *tok) {
-  add_type(lhs);
-  add_type(rhs);
-
-  // num - num
-  if (is_numeric(lhs->ty) && is_numeric(rhs->ty))
-    return new_binary(ND_SUB, lhs, rhs, tok);
-
-  // VLA + num
-  if (lhs->ty->base->kind == TY_VLA) {
-    rhs = new_binary(ND_MUL, rhs, new_var_node(lhs->ty->base->vla_size, tok), tok);
-    add_type(rhs);
-    Node *node = new_binary(ND_SUB, lhs, rhs, tok);
-    node->ty = lhs->ty;
-    return node;
-  }
-
-  // ptr - num
-  if (lhs->ty->base && is_integer(rhs->ty)) {
-    rhs = new_binary(ND_MUL, rhs, new_long(lhs->ty->base->size, tok), tok);
-    add_type(rhs);
-    Node *node = new_binary(ND_SUB, lhs, rhs, tok);
-    node->ty = lhs->ty;
-    return node;
-  }
-
-  // ptr - ptr, which returns how many elements are between the two.
-  if (lhs->ty->base && rhs->ty->base) {
-    Node *node = new_binary(ND_SUB, lhs, rhs, tok);
-    node->ty = ty_long;
-    return new_binary(ND_DIV, node, new_num(lhs->ty->base->size, tok), tok);
-  }
-
-  error_tok(tok, "invalid operands");
-}
-
-// add = mul ("+" mul | "-" mul)*
-static Node *add(Token **rest, Token *tok) {
-  Node *node = mul(&tok, tok);
-
-  for (;;) {
-    Token *start = tok;
-
-    if (equal(tok, "+")) {
-      node = new_add(node, mul(&tok, tok->next), start);
-      continue;
-    }
-
-    if (equal(tok, "-")) {
-      node = new_sub(node, mul(&tok, tok->next), start);
-      continue;
-    }
-
-    *rest = tok;
-    return node;
-  }
-}
-
-// mul = cast ("*" cast | "/" cast | "%" cast)*
-static Node *mul(Token **rest, Token *tok) {
-  Node *node = cast(&tok, tok);
-
-  for (;;) {
-    Token *start = tok;
-
-    if (equal(tok, "*")) {
-      node = new_binary(ND_MUL, node, cast(&tok, tok->next), start);
-      continue;
-    }
-
-    if (equal(tok, "/")) {
-      node = new_binary(ND_DIV, node, cast(&tok, tok->next), start);
-      continue;
-    }
-
-    if (equal(tok, "%")) {
-      node = new_binary(ND_MOD, node, cast(&tok, tok->next), start);
-      continue;
-    }
-
-    *rest = tok;
-    return node;
-  }
-}
-
-// cast = "(" type-name ")" cast | unary
-static Node *cast(Token **rest, Token *tok) {
-  if (equal(tok, "(") && is_typename(tok->next)) {
-    Token *start = tok;
-    Type *ty = typename(&tok, tok->next);
-    tok = skip(tok, ")");
-
-    // compound literal
-    if (equal(tok, "{"))
-      return unary(rest, start);
-
-    // type cast
-    Node *node = new_cast(cast(rest, tok), ty);
-    node->tok = start;
-    return node;
-  }
-
-  return unary(rest, tok);
-}
-
-// unary = ("+" | "-" | "*" | "&" | "!" | "~") cast
-//       | ("++" | "--") unary
-//       | "&&" ident
-//       | postfix
-static Node *unary(Token **rest, Token *tok) {
-  if (equal(tok, "+"))
-    return cast(rest, tok->next);
-
-  if (equal(tok, "-"))
-    return new_unary(ND_NEG, cast(rest, tok->next), tok);
-
-  if (equal(tok, "&")) {
-    Node *lhs = cast(rest, tok->next);
-    add_type(lhs);
-    if (lhs->kind == ND_MEMBER && lhs->member->is_bitfield)
-      error_tok(tok, "cannot take address of bitfield");
-    return new_unary(ND_ADDR, lhs, tok);
-  }
-
-  if (equal(tok, "*")) {
-    // [https://www.sigbus.info/n1570#6.5.3.2p4] This is an oddity
-    // in the C spec, but dereferencing a function shouldn't do
-    // anything. If foo is a function, `*foo`, `**foo` or `*****foo`
-    // are all equivalent to just `foo`.
-    Node *node = cast(rest, tok->next);
-    add_type(node);
-    if (node->ty->kind == TY_FUNC)
-      return node;
-    return new_unary(ND_DEREF, node, tok);
-  }
-
-  if (equal(tok, "!"))
-    return new_unary(ND_NOT, cast(rest, tok->next), tok);
-
-  if (equal(tok, "~"))
-    return new_unary(ND_BITNOT, cast(rest, tok->next), tok);
-
-  // Read ++i as i+=1
-  if (equal(tok, "++"))
-    return to_assign(new_add(unary(rest, tok->next), new_num(1, tok), tok));
-
-  // Read --i as i-=1
-  if (equal(tok, "--"))
-    return to_assign(new_sub(unary(rest, tok->next), new_num(1, tok), tok));
-
-  // [GNU] labels-as-values
-  if (equal(tok, "&&")) {
-    Node *node = new_node(ND_LABEL_VAL, tok);
-    node->label = get_ident(tok->next);
-    node->goto_next = gotos;
-    gotos = node;
-    *rest = tok->next->next;
-    return node;
-  }
-
-  return postfix(rest, tok);
-}
-
-// struct-members = (declspec declarator (","  declarator)* ";")*
-static void struct_members(Token **rest, Token *tok, Type *ty) {
-  Member head = {};
-  Member *cur = &head;
-  int idx = 0;
-
-  while (!equal(tok, "}")) {
-    VarAttr attr = {};
-    Type *basety = declspec(&tok, tok, &attr);
-    bool first = true;
-
-    // Anonymous struct member
-    if ((basety->kind == TY_STRUCT || basety->kind == TY_UNION) &&
-        consume(&tok, tok, ";")) {
-      Member *mem = calloc(1, sizeof(Member));
-      mem->ty = basety;
-      mem->idx = idx++;
-      mem->align = attr.align ? attr.align : mem->ty->align;
-      cur = cur->next = mem;
-      continue;
-    }
-
-    // Regular struct members
-    while (!consume(&tok, tok, ";")) {
-      if (!first)
-        tok = skip(tok, ",");
-      first = false;
-
-      Member *mem = calloc(1, sizeof(Member));
-      mem->ty = declarator(&tok, tok, basety);
-      mem->name = mem->ty->name;
-      mem->idx = idx++;
-      mem->align = attr.align ? attr.align : mem->ty->align;
-
-      if (consume(&tok, tok, ":")) {
-        mem->is_bitfield = true;
-        mem->bit_width = const_expr(&tok, tok);
-      }
-
-      cur = cur->next = mem;
-    }
-  }
-
-  // If the last element is an array of incomplete type, it's
-  // called a "flexible array member". It should behave as if
-  // if were a zero-sized array.
-  if (cur != &head && cur->ty->kind == TY_ARRAY && cur->ty->array_len < 0) {
-    cur->ty = array_of(cur->ty->base, 0);
-    ty->is_flexible = true;
-  }
-
-  *rest = tok->next;
-  ty->members = head.next;
-}
-
-// attribute = ("__attribute__" "(" "(" "packed" ")" ")")*
-static Token *attribute_list(Token *tok, Type *ty) {
-  while (consume(&tok, tok, "__attribute__")) {
-    tok = skip(tok, "(");
-    tok = skip(tok, "(");
-
-    bool first = true;
-
-    while (!consume(&tok, tok, ")")) {
-      if (!first)
-        tok = skip(tok, ",");
-      first = false;
-
-      if (consume(&tok, tok, "packed")) {
-        ty->is_packed = true;
-        continue;
-      }
-
-      if (consume(&tok, tok, "aligned")) {
-        tok = skip(tok, "(");
-        ty->align = const_expr(&tok, tok);
-        tok = skip(tok, ")");
-        continue;
-      }
-
-      error_tok(tok, "unknown attribute");
-    }
-
-    tok = skip(tok, ")");
-  }
-
-  return tok;
-}
-
-// struct-union-decl = attribute? ident? ("{" struct-members)?
-static Type *struct_union_decl(Token **rest, Token *tok) {
-  Type *ty = struct_type();
-  tok = attribute_list(tok, ty);
-
-  // Read a tag.
-  Token *tag = NULL;
-  if (tok->kind == TK_IDENT) {
-    tag = tok;
-    tok = tok->next;
-  }
-
-  if (tag && !equal(tok, "{")) {
-    *rest = tok;
-
-    Type *ty2 = find_tag(tag);
-    if (ty2)
-      return ty2;
-
-    ty->size = -1;
-    push_tag_scope(tag, ty);
-    return ty;
-  }
-
-  tok = skip(tok, "{");
-
-  // Construct a struct object.
-  struct_members(&tok, tok, ty);
-  *rest = attribute_list(tok, ty);
-
-  if (tag) {
-    // If this is a redefinition, overwrite a previous type.
-    // Otherwise, register the struct type.
-    Type *ty2 = hashmap_get2(&scope->tags, tag->loc, tag->len);
-    if (ty2) {
-      *ty2 = *ty;
-      return ty2;
-    }
-
-    push_tag_scope(tag, ty);
-  }
-
-  return ty;
-}
-
-// struct-decl = struct-union-decl
-static Type *struct_decl(Token **rest, Token *tok) {
-  Type *ty = struct_union_decl(rest, tok);
-  ty->kind = TY_STRUCT;
-
-  if (ty->size < 0)
-    return ty;
-
-  // Assign offsets within the struct to members.
-  int bits = 0;
-
-  for (Member *mem = ty->members; mem; mem = mem->next) {
-    if (mem->is_bitfield && mem->bit_width == 0) {
-      // Zero-width anonymous bitfield has a special meaning.
-      // It affects only alignment.
-      bits = align_to(bits, mem->ty->size * 8);
-    } else if (mem->is_bitfield) {
-      int sz = mem->ty->size;
-      if (bits / (sz * 8) != (bits + mem->bit_width - 1) / (sz * 8))
-        bits = align_to(bits, sz * 8);
-
-      mem->offset = align_down(bits / 8, sz);
-      mem->bit_offset = bits % (sz * 8);
-      bits += mem->bit_width;
-    } else {
-      if (!ty->is_packed)
-        bits = align_to(bits, mem->align * 8);
-      mem->offset = bits / 8;
-      bits += mem->ty->size * 8;
-    }
-
-    if (!ty->is_packed && ty->align < mem->align)
-      ty->align = mem->align;
-  }
-
-  ty->size = align_to(bits, ty->align * 8) / 8;
-  return ty;
-}
-
-// union-decl = struct-union-decl
-static Type *union_decl(Token **rest, Token *tok) {
-  Type *ty = struct_union_decl(rest, tok);
-  ty->kind = TY_UNION;
-
-  if (ty->size < 0)
-    return ty;
-
-  // If union, we don't have to assign offsets because they
-  // are already initialized to zero. We need to compute the
-  // alignment and the size though.
-  for (Member *mem = ty->members; mem; mem = mem->next) {
-    if (ty->align < mem->align)
-      ty->align = mem->align;
-    if (ty->size < mem->ty->size)
-      ty->size = mem->ty->size;
-  }
-  ty->size = align_to(ty->size, ty->align);
-  return ty;
-}
-
-// Find a struct member by name.
-static Member *get_struct_member(Type *ty, Token *tok) {
-  for (Member *mem = ty->members; mem; mem = mem->next) {
-    // Anonymous struct member
-    if ((mem->ty->kind == TY_STRUCT || mem->ty->kind == TY_UNION) &&
-        !mem->name) {
-      if (get_struct_member(mem->ty, tok))
-        return mem;
-      continue;
-    }
-
-    // Regular struct member
-    if (mem->name->len == tok->len &&
-        !strncmp(mem->name->loc, tok->loc, tok->len))
-      return mem;
-  }
-  return NULL;
-}
-
-// Create a node representing a struct member access, such as foo.bar
-// where foo is a struct and bar is a member name.
-//
-// C has a feature called "anonymous struct" which allows a struct to
-// have another unnamed struct as a member like this:
-//
-//   struct { struct { int a; }; int b; } x;
-//
-// The members of an anonymous struct belong to the outer struct's
-// member namespace. Therefore, in the above example, you can access
-// member "a" of the anonymous struct as "x.a".
-//
-// This function takes care of anonymous structs.
-static Node *struct_ref(Node *node, Token *tok) {
-  add_type(node);
-  if (node->ty->kind != TY_STRUCT && node->ty->kind != TY_UNION)
-    error_tok(node->tok, "not a struct nor a union");
-
-  Type *ty = node->ty;
-
-  for (;;) {
-    Member *mem = get_struct_member(ty, tok);
-    if (!mem)
-      error_tok(tok, "no such member");
-    node = new_unary(ND_MEMBER, node, tok);
-    node->member = mem;
-    if (mem->name)
-      break;
-    ty = mem->ty;
-  }
-  return node;
-}
-
-// Convert A++ to `(typeof A)((A += 1) - 1)`
-static Node *new_inc_dec(Node *node, Token *tok, int addend) {
-  add_type(node);
-  return new_cast(new_add(to_assign(new_add(node, new_num(addend, tok), tok)),
-                          new_num(-addend, tok), tok),
-                  node->ty);
-}
-
-// postfix = "(" type-name ")" "{" initializer-list "}"
-//         = ident "(" func-args ")" postfix-tail*
-//         | primary postfix-tail*
-//
-// postfix-tail = "[" expr "]"
-//              | "(" func-args ")"
-//              | "." ident
-//              | "->" ident
-//              | "++"
-//              | "--"
-static Node *postfix(Token **rest, Token *tok) {
-  if (equal(tok, "(") && is_typename(tok->next)) {
-    // Compound literal
-    Token *start = tok;
-    Type *ty = typename(&tok, tok->next);
-    tok = skip(tok, ")");
-
-    if (scope->next == NULL) {
-      Obj *var = new_anon_gvar(ty);
-      gvar_initializer(rest, tok, var);
-      return new_var_node(var, start);
-    }
-
-    Obj *var = new_lvar("", ty);
-    Node *lhs = lvar_initializer(rest, tok, var);
-    Node *rhs = new_var_node(var, tok);
-    return new_binary(ND_COMMA, lhs, rhs, start);
-  }
-
-  Node *node = primary(&tok, tok);
-
-  for (;;) {
-    if (equal(tok, "(")) {
-      node = funcall(&tok, tok->next, node);
-      continue;
-    }
-
-    if (equal(tok, "[")) {
-      // x[y] is short for *(x+y)
-      Token *start = tok;
-      Node *idx = expr(&tok, tok->next);
-      tok = skip(tok, "]");
-      node = new_unary(ND_DEREF, new_add(node, idx, start), start);
-      continue;
-    }
-
-    if (equal(tok, ".")) {
-      node = struct_ref(node, tok->next);
-      tok = tok->next->next;
-      continue;
-    }
-
-    if (equal(tok, "->")) {
-      // x->y is short for (*x).y
-      node = new_unary(ND_DEREF, node, tok);
-      node = struct_ref(node, tok->next);
-      tok = tok->next->next;
-      continue;
-    }
-
-    if (equal(tok, "++")) {
-      node = new_inc_dec(node, tok, 1);
-      tok = tok->next;
-      continue;
-    }
-
-    if (equal(tok, "--")) {
-      node = new_inc_dec(node, tok, -1);
-      tok = tok->next;
-      continue;
-    }
-
-    *rest = tok;
-    return node;
-  }
-}
-
-// funcall = (assign ("," assign)*)? ")"
-static Node *funcall(Token **rest, Token *tok, Node *fn) {
-  add_type(fn);
-
-  if (fn->ty->kind != TY_FUNC &&
-      (fn->ty->kind != TY_PTR || fn->ty->base->kind != TY_FUNC))
-    error_tok(fn->tok, "not a function");
-
-  Type *ty = (fn->ty->kind == TY_FUNC) ? fn->ty : fn->ty->base;
-  Type *param_ty = ty->params;
-
-  Node head = {};
-  Node *cur = &head;
-
-  while (!equal(tok, ")")) {
-    if (cur != &head)
-      tok = skip(tok, ",");
-
-    Node *arg = assign(&tok, tok);
-    add_type(arg);
-
-    if (!param_ty && !ty->is_variadic)
-      error_tok(tok, "too many arguments");
-
-    if (param_ty) {
-      if (param_ty->kind != TY_STRUCT && param_ty->kind != TY_UNION)
-        arg = new_cast(arg, param_ty);
-      param_ty = param_ty->next;
-    } else if (arg->ty->kind == TY_FLOAT) {
-      // If parameter type is omitted (e.g. in "..."), float
-      // arguments are promoted to double.
-      arg = new_cast(arg, ty_double);
-    }
-
-    cur = cur->next = arg;
-  }
-
-  if (param_ty)
-    error_tok(tok, "too few arguments");
-
-  *rest = skip(tok, ")");
-
-  Node *node = new_unary(ND_FUNCALL, fn, tok);
-  node->func_ty = ty;
-  node->ty = ty->return_ty;
-  node->args = head.next;
-
-  // If a function returns a struct, it is caller's responsibility
-  // to allocate a space for the return value.
-  if (node->ty->kind == TY_STRUCT || node->ty->kind == TY_UNION)
-    node->ret_buffer = new_lvar("", node->ty);
-  return node;
-}
-
-// generic-selection = "(" assign "," generic-assoc ("," generic-assoc)* ")"
-//
-// generic-assoc = type-name ":" assign
-//               | "default" ":" assign
-static Node *generic_selection(Token **rest, Token *tok) {
-  Token *start = tok;
-  tok = skip(tok, "(");
-
-  Node *ctrl = assign(&tok, tok);
-  add_type(ctrl);
-
-  Type *t1 = ctrl->ty;
-  if (t1->kind == TY_FUNC)
-    t1 = pointer_to(t1);
-  else if (t1->kind == TY_ARRAY)
-    t1 = pointer_to(t1->base);
-
-  Node *ret = NULL;
-
-  while (!consume(rest, tok, ")")) {
-    tok = skip(tok, ",");
-
-    if (equal(tok, "default")) {
-      tok = skip(tok->next, ":");
-      Node *node = assign(&tok, tok);
-      if (!ret)
-        ret = node;
-      continue;
-    }
-
-    Type *t2 = typename(&tok, tok);
-    tok = skip(tok, ":");
-    Node *node = assign(&tok, tok);
-    if (is_compatible(t1, t2))
-      ret = node;
-  }
-
-  if (!ret)
-    error_tok(start, "controlling expression type not compatible with"
-              " any generic association type");
-  return ret;
-}
-
-// primary = "(" "{" stmt+ "}" ")"
-//         | "(" expr ")"
-//         | "sizeof" "(" type-name ")"
-//         | "sizeof" unary
-//         | "_Alignof" "(" type-name ")"
-//         | "_Alignof" unary
-//         | "_Generic" generic-selection
-//         | "__builtin_types_compatible_p" "(" type-name, type-name, ")"
-//         | "__builtin_reg_class" "(" type-name ")"
-//         | ident
-//         | str
-//         | num
-static Node *primary(Token **rest, Token *tok) {
-  Token *start = tok;
-
-  if (equal(tok, "(") && equal(tok->next, "{")) {
-    // This is a GNU statement expresssion.
-    Node *node = new_node(ND_STMT_EXPR, tok);
-    node->body = compound_stmt(&tok, tok->next->next)->body;
-    *rest = skip(tok, ")");
-    return node;
-  }
-
-  if (equal(tok, "(")) {
-    Node *node = expr(&tok, tok->next);
-    *rest = skip(tok, ")");
-    return node;
-  }
-
-  if (equal(tok, "sizeof") && equal(tok->next, "(") && is_typename(tok->next->next)) {
-    Type *ty = typename(&tok, tok->next->next);
-    *rest = skip(tok, ")");
-
-    if (ty->kind == TY_VLA) {
-      if (ty->vla_size)
-        return new_var_node(ty->vla_size, tok);
-
-      Node *lhs = compute_vla_size(ty, tok);
-      Node *rhs = new_var_node(ty->vla_size, tok);
-      return new_binary(ND_COMMA, lhs, rhs, tok);
-    }
-
-    return new_ulong(ty->size, start);
-  }
-
-  if (equal(tok, "sizeof")) {
-    Node *node = unary(rest, tok->next);
-    add_type(node);
-    if (node->ty->kind == TY_VLA)
-      return new_var_node(node->ty->vla_size, tok);
-    return new_ulong(node->ty->size, tok);
-  }
-
-  if (equal(tok, "_Alignof") && equal(tok->next, "(") && is_typename(tok->next->next)) {
-    Type *ty = typename(&tok, tok->next->next);
-    *rest = skip(tok, ")");
-    return new_ulong(ty->align, tok);
-  }
-
-  if (equal(tok, "_Alignof")) {
-    Node *node = unary(rest, tok->next);
-    add_type(node);
-    return new_ulong(node->ty->align, tok);
-  }
-
-  if (equal(tok, "_Generic"))
-    return generic_selection(rest, tok->next);
-
-  if (equal(tok, "__builtin_types_compatible_p")) {
-    tok = skip(tok->next, "(");
-    Type *t1 = typename(&tok, tok);
-    tok = skip(tok, ",");
-    Type *t2 = typename(&tok, tok);
-    *rest = skip(tok, ")");
-    return new_num(is_compatible(t1, t2), start);
-  }
-
-  if (equal(tok, "__builtin_reg_class")) {
-    tok = skip(tok->next, "(");
-    Type *ty = typename(&tok, tok);
-    *rest = skip(tok, ")");
-
-    if (is_integer(ty) || ty->kind == TY_PTR)
-      return new_num(0, start);
-    if (is_flonum(ty))
-      return new_num(1, start);
-    return new_num(2, start);
-  }
-
-  if (equal(tok, "__builtin_compare_and_swap")) {
-    Node *node = new_node(ND_CAS, tok);
-    tok = skip(tok->next, "(");
-    node->cas_addr = assign(&tok, tok);
-    tok = skip(tok, ",");
-    node->cas_old = assign(&tok, tok);
-    tok = skip(tok, ",");
-    node->cas_new = assign(&tok, tok);
-    *rest = skip(tok, ")");
-    return node;
-  }
-
-  if (equal(tok, "__builtin_atomic_exchange")) {
-    Node *node = new_node(ND_EXCH, tok);
-    tok = skip(tok->next, "(");
-    node->lhs = assign(&tok, tok);
-    tok = skip(tok, ",");
-    node->rhs = assign(&tok, tok);
-    *rest = skip(tok, ")");
-    return node;
-  }
-
-  if (tok->kind == TK_IDENT) {
-    // Variable or enum constant
-    VarScope *sc = find_var(tok);
-    *rest = tok->next;
-
-    // For "static inline" function
-    if (sc && sc->var && sc->var->is_function) {
-      if (current_fn)
-        strarray_push(&current_fn->refs, sc->var->name);
-      else
-        sc->var->is_root = true;
-    }
-
-    if (sc) {
-      if (sc->var)
-        return new_var_node(sc->var, tok);
-      if (sc->enum_ty)
-        return new_num(sc->enum_val, tok);
-    }
-
-    if (equal(tok->next, "("))
-      error_tok(tok, "implicit declaration of a function");
-    error_tok(tok, "undefined variable");
-  }
-
-  if (tok->kind == TK_STR) {
-    Obj *var = new_string_literal(tok->str, tok->ty);
-    *rest = tok->next;
-    return new_var_node(var, tok);
-  }
-
-  if (tok->kind == TK_NUM) {
-    Node *node;
-    if (is_flonum(tok->ty)) {
-      node = new_node(ND_NUM, tok);
-      node->fval = tok->fval;
-    } else {
-      node = new_num(tok->val, tok);
-    }
-
-    node->ty = tok->ty;
-    *rest = tok->next;
-    return node;
-  }
-
-  error_tok(tok, "expected an expression");
-}
-
-static Token *parse_typedef(Token *tok, Type *basety) {
-  bool first = true;
-
-  while (!consume(&tok, tok, ";")) {
-    if (!first)
-      tok = skip(tok, ",");
-    first = false;
-
-    Type *ty = declarator(&tok, tok, basety);
-    if (!ty->name)
-      error_tok(ty->name_pos, "typedef name omitted");
-    push_scope(get_ident(ty->name))->type_def = ty;
-  }
-  return tok;
-}
-
-static void create_param_lvars(Type *param) {
-  if (param) {
-    create_param_lvars(param->next);
-    if (!param->name)
-      error_tok(param->name_pos, "parameter name omitted");
-    new_lvar(get_ident(param->name), param);
-  }
-}
-
-// This function matches gotos or labels-as-values with labels.
-//
-// We cannot resolve gotos as we parse a function because gotos
-// can refer a label that appears later in the function.
-// So, we need to do this after we parse the entire function.
-static void resolve_goto_labels(void) {
-  for (Node *x = gotos; x; x = x->goto_next) {
-    for (Node *y = labels; y; y = y->goto_next) {
-      if (!strcmp(x->label, y->label)) {
-        x->unique_label = y->unique_label;
-        break;
-      }
-    }
-
-    if (x->unique_label == NULL)
-      error_tok(x->tok->next, "use of undeclared label");
-  }
-
-  gotos = labels = NULL;
-}
-
-static Obj *find_func(char *name) {
-  Scope *sc = scope;
-  while (sc->next)
-    sc = sc->next;
-
-  VarScope *sc2 = hashmap_get(&sc->vars, name);
-  if (sc2 && sc2->var && sc2->var->is_function)
-    return sc2->var;
-  return NULL;
-}
-
-static void mark_live(Obj *var) {
-  if (!var->is_function || var->is_live)
-    return;
-  var->is_live = true;
-
-  for (int i = 0; i < var->refs.len; i++) {
-    Obj *fn = find_func(var->refs.data[i]);
-    if (fn)
-      mark_live(fn);
-  }
-}
-
-static Token *function(Token *tok, Type *basety, VarAttr *attr) {
-  Type *ty = declarator(&tok, tok, basety);
-  if (!ty->name)
-    error_tok(ty->name_pos, "function name omitted");
-  char *name_str = get_ident(ty->name);
-
-  Obj *fn = find_func(name_str);
-  if (fn) {
-    // Redeclaration
-    if (!fn->is_function)
-      error_tok(tok, "redeclared as a different kind of symbol");
-    if (fn->is_definition && equal(tok, "{"))
-      error_tok(tok, "redefinition of %s", name_str);
-    if (!fn->is_static && attr->is_static)
-      error_tok(tok, "static declaration follows a non-static declaration");
-    fn->is_definition = fn->is_definition || equal(tok, "{");
-  } else {
-    fn = new_gvar(name_str, ty);
-    fn->is_function = true;
-    fn->is_definition = equal(tok, "{");
-    fn->is_static = attr->is_static || (attr->is_inline && !attr->is_extern);
-    fn->is_inline = attr->is_inline;
-  }
-
-  fn->is_root = !(fn->is_static && fn->is_inline);
-
-  if (consume(&tok, tok, ";"))
-    return tok;
-
-  current_fn = fn;
-  locals = NULL;
-  enter_scope();
-  create_param_lvars(ty->params);
-
-  // A buffer for a struct/union return value is passed
-  // as the hidden first parameter.
-  Type *rty = ty->return_ty;
-  if ((rty->kind == TY_STRUCT || rty->kind == TY_UNION) && rty->size > 16)
-    new_lvar("", pointer_to(rty));
-
-  fn->params = locals;
-
-  if (ty->is_variadic)
-    fn->va_area = new_lvar("__va_area__", array_of(ty_char, 136));
-  fn->alloca_bottom = new_lvar("__alloca_size__", pointer_to(ty_char));
-
-  tok = skip(tok, "{");
-
-  // [https://www.sigbus.info/n1570#6.4.2.2p1] "__func__" is
-  // automatically defined as a local variable containing the
-  // current function name.
-  push_scope("__func__")->var =
-    new_string_literal(fn->name, array_of(ty_char, strlen(fn->name) + 1));
-
-  // [GNU] __FUNCTION__ is yet another name of __func__.
-  push_scope("__FUNCTION__")->var =
-    new_string_literal(fn->name, array_of(ty_char, strlen(fn->name) + 1));
-
-  fn->body = compound_stmt(&tok, tok);
-  fn->locals = locals;
-  leave_scope();
-  resolve_goto_labels();
-  return tok;
-}
-
-static Token *global_variable(Token *tok, Type *basety, VarAttr *attr) {
-  bool first = true;
-
-  while (!consume(&tok, tok, ";")) {
-    if (!first)
-      tok = skip(tok, ",");
-    first = false;
-
-    Type *ty = declarator(&tok, tok, basety);
-    if (!ty->name)
-      error_tok(ty->name_pos, "variable name omitted");
-
-    Obj *var = new_gvar(get_ident(ty->name), ty);
-    var->is_definition = !attr->is_extern;
-    var->is_static = attr->is_static;
-    var->is_tls = attr->is_tls;
-    if (attr->align)
-      var->align = attr->align;
-
-    if (equal(tok, "="))
-      gvar_initializer(&tok, tok->next, var);
-    else if (!attr->is_extern && !attr->is_tls)
-      var->is_tentative = true;
-  }
-  return tok;
-}
-
-// Lookahead tokens and returns true if a given token is a start
-// of a function definition or declaration.
-static bool is_function(Token *tok) {
-  if (equal(tok, ";"))
-    return false;
-
-  Type dummy = {};
-  Type *ty = declarator(&tok, tok, &dummy);
-  return ty->kind == TY_FUNC;
-}
-
-// Remove redundant tentative definitions.
-static void scan_globals(void) {
-  Obj head;
-  Obj *cur = &head;
-
-  for (Obj *var = globals; var; var = var->next) {
-    if (!var->is_tentative) {
-      cur = cur->next = var;
-      continue;
-    }
-
-    // Find another definition of the same identifier.
-    Obj *var2 = globals;
-    for (; var2; var2 = var2->next)
-      if (var != var2 && var2->is_definition && !strcmp(var->name, var2->name))
-        break;
-
-    // If there's another definition, the tentative definition
-    // is redundant
-    if (!var2)
-      cur = cur->next = var;
-  }
-
-  cur->next = NULL;
-  globals = head.next;
-}
-
-static void declare_builtin_functions(void) {
-  Type *ty = func_type(pointer_to(ty_void));
-  ty->params = copy_type(ty_int);
-  builtin_alloca = new_gvar("alloca", ty);
-  builtin_alloca->is_definition = false;
-}
-
-// program = (typedef | function-definition | global-variable)*
-Obj *parse(Token *tok) {
-  declare_builtin_functions();
-  globals = NULL;
-
-  while (tok->kind != TK_EOF) {
-    VarAttr attr = {};
-    Type *basety = declspec(&tok, tok, &attr);
-
-    // Typedef
-    if (attr.is_typedef) {
-      tok = parse_typedef(tok, basety);
-      continue;
-    }
-
-    // Function
-    if (is_function(tok)) {
-      tok = function(tok, basety, &attr);
-      continue;
-    }
-
-    // Global variable
-    tok = global_variable(tok, basety, &attr);
-  }
-
-  for (Obj *var = globals; var; var = var->next)
-    if (var->is_root)
-      mark_live(var);
-
-  // Remove redundant tentative definitions.
-  scan_globals();
-  return globals;
-}