*/
#define EXPR_STMT_STMT_EXPR_RESULT(NODE) \
  TREE_LANG_FLAG_0 (EXPR_STMT_CHECK (NODE))

/* Nonzero if this statement-expression does not have an associated scope.  */
#define STMT_EXPR_NO_SCOPE(NODE) \
   TREE_LANG_FLAG_0 (STMT_EXPR_CHECK (NODE))

#define COND_EXPR_IS_VEC_DELETE(NODE) \
  TREE_LANG_FLAG_0 (COND_EXPR_CHECK (NODE))

/* Nonzero if this NOP_EXPR is a reinterpret_cast.  Such conversions
   are not constexprs.  Other NOP_EXPRs are.  */
#define REINTERPRET_CAST_P(NODE)		\
  TREE_LANG_FLAG_0 (NOP_EXPR_CHECK (NODE))

/* Returns nonzero iff TYPE1 and TYPE2 are the same type, in the usual
   sense of `same'.  */
#define same_type_p(TYPE1, TYPE2) \
  comptypes ((TYPE1), (TYPE2), COMPARE_STRICT)

/* Returns nonzero iff NODE is a declaration for the global function
   `main'.  */
#define DECL_MAIN_ANY_P(NODE)				\
   (DECL_EXTERN_C_FUNCTION_P (NODE)			\
    && DECL_NAME (NODE) != NULL_TREE			\
    && MAIN_NAME_P (DECL_NAME (NODE)))

/* Nonzero iff NODE is a declaration for `int main', or we are hosted. */
#define DECL_MAIN_FREESTANDING_P(NODE)				\
  (DECL_MAIN_ANY_P(NODE)					\
   && (flag_hosted						\
       || TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (NODE)))	\
	  == integer_type_node))

/* Nonzero iff NODE is a declaration for `main', and we are hosted. */
#define DECL_MAIN_P(NODE) (DECL_MAIN_ANY_P(NODE) && flag_hosted)

/* Lookup walker marking.  */
#define LOOKUP_SEEN_P(NODE) TREE_VISITED (NODE)
#define LOOKUP_FOUND_P(NODE) \
  TREE_LANG_FLAG_4 (TREE_CHECK4 (NODE,RECORD_TYPE,UNION_TYPE,ENUMERAL_TYPE,\
				 NAMESPACE_DECL))

/* These two accessors should only be used by OVL manipulators.
   Other users should use iterators and convenience functions.  */
#define OVL_FUNCTION(NODE) \
  (((struct tree_overload*)OVERLOAD_CHECK (NODE))->function)
#define OVL_CHAIN(NODE) \
  (((struct tree_overload*)OVERLOAD_CHECK (NODE))->common.chain)

/* If set, this or a subsequent overload contains decls that need deduping.  */
#define OVL_DEDUP_P(NODE)	TREE_LANG_FLAG_0 (OVERLOAD_CHECK (NODE))
/* If set, this was imported in a using declaration.   */
#define OVL_USING_P(NODE)	TREE_LANG_FLAG_1 (OVERLOAD_CHECK (NODE))
/* If set, this overload is a hidden decl.  */
#define OVL_HIDDEN_P(NODE)	TREE_LANG_FLAG_2 (OVERLOAD_CHECK (NODE))
/* If set, this overload contains a nested overload.  */
#define OVL_NESTED_P(NODE)	TREE_LANG_FLAG_3 (OVERLOAD_CHECK (NODE))
/* If set, this overload was constructed during lookup.  */
#define OVL_LOOKUP_P(NODE)	TREE_LANG_FLAG_4 (OVERLOAD_CHECK (NODE))
/* If set, this OVL_USING_P overload is exported.  */
#define OVL_EXPORT_P(NODE)	TREE_LANG_FLAG_5 (OVERLOAD_CHECK (NODE))

/* The first decl of an overload.  */
#define OVL_FIRST(NODE)	ovl_first (NODE)
/* The name of the overload set.  */
#define OVL_NAME(NODE) DECL_NAME (OVL_FIRST (NODE))

/* Whether this is a set of overloaded functions.  TEMPLATE_DECLS are
   always wrapped in an OVERLOAD, so we don't need to check them
   here.  */
#define OVL_P(NODE) \
  (TREE_CODE (NODE) == FUNCTION_DECL || TREE_CODE (NODE) == OVERLOAD)
/* Whether this is a single member overload.  */
#define OVL_SINGLE_P(NODE) \
  (TREE_CODE (NODE) != OVERLOAD || !OVL_CHAIN (NODE))

/* OVL_HIDDEN_P nodes come before other nodes.  */

struct GTY(()) tree_overload {
  struct tree_common common;
  tree function;
};

/* Iterator for a 1 dimensional overload.  Permits iterating over the
   outer level of a 2-d overload when explicitly enabled.  */

class ovl_iterator {
  tree ovl;
  const bool allow_inner; /* Only used when checking.  */

 public:
  explicit ovl_iterator (tree o, bool allow = false)
    : ovl (o), allow_inner (allow)
  {
  }

 public:
  operator bool () const
  {
    return ovl;
  }
  ovl_iterator &operator++ ()
  {
    ovl = TREE_CODE (ovl) != OVERLOAD ? NULL_TREE : OVL_CHAIN (ovl);
    return *this;
  }
  tree operator* () const
  {
    tree fn = TREE_CODE (ovl) != OVERLOAD ? ovl : OVL_FUNCTION (ovl);

    /* Check this is not an unexpected 2-dimensional overload.  */
    gcc_checking_assert (allow_inner || TREE_CODE (fn) != OVERLOAD);

    return fn;
  }
  bool operator== (const ovl_iterator &o) const
  {
    return ovl == o.ovl;
  }
  tree get_using () const
  {
    gcc_checking_assert (using_p ());
    return ovl;
  }

 public:
  /* Whether this overload was introduced by a using decl.  */
  bool using_p () const
  {
    return (TREE_CODE (ovl) == USING_DECL
	    || (TREE_CODE (ovl) == OVERLOAD && OVL_USING_P (ovl)));
  }
  /* Whether this using is being exported.  */
  bool exporting_p () const
  {
    return OVL_EXPORT_P (get_using ());
  }
  
  bool hidden_p () const
  {
    return TREE_CODE (ovl) == OVERLOAD && OVL_HIDDEN_P (ovl);
  }

 public:
  tree remove_node (tree head)
  {
    return remove_node (head, ovl);
  }
  tree reveal_node (tree head)
  {
    return reveal_node (head, ovl);
  }

 protected:
  /* If we have a nested overload, point at the inner overload and
     return the next link on the outer one.  */
  tree maybe_push ()
  {
    tree r = NULL_TREE;

    if (ovl && TREE_CODE (ovl) == OVERLOAD && OVL_NESTED_P (ovl))
      {
	r = OVL_CHAIN (ovl);
	ovl = OVL_FUNCTION (ovl);
      }
    return r;
  }
  /* Restore an outer nested overload.  */
  void pop (tree outer)
  {
    gcc_checking_assert (!ovl);
    ovl = outer;
  }

 private:
  /* We make these static functions to avoid the address of the
     iterator escaping the local context.  */
  static tree remove_node (tree head, tree node);
  static tree reveal_node (tree ovl, tree node);
};

/* Treat a tree as a range of ovl_iterator, e.g.
   for (tree f : ovl_range (fns)) { ... }  */

class ovl_range
{
  tree t;
  bool allow;
public:
  explicit ovl_range (tree t, bool allow = false): t(t), allow(allow) { }
  ovl_iterator begin() { return ovl_iterator (t, allow); }
  ovl_iterator end() { return ovl_iterator (NULL_TREE, allow); }
};

/* Iterator over a (potentially) 2 dimensional overload, which is
   produced by name lookup.  */

class lkp_iterator : public ovl_iterator {
  typedef ovl_iterator parent;

  tree outer;

 public:
  explicit lkp_iterator (tree o)
    : parent (o, true), outer (maybe_push ())
  {
  }

 public:
  lkp_iterator &operator++ ()
  {
    bool repush = !outer;

    if (!parent::operator++ () && !repush)
      {
	pop (outer);
	repush = true;
      }

    if (repush)
      outer = maybe_push ();

    return *this;
  }
};

/* Treat a tree as a range of lkp_iterator, e.g.
   for (tree f : lkp_range (fns)) { ... }  */

class lkp_range
{
  tree t;
public:
  lkp_range (tree t): t(t) { }
  lkp_iterator begin() { return lkp_iterator (t); }
  lkp_iterator end() { return lkp_iterator (NULL_TREE); }
};

/* hash traits for declarations.  Hashes potential overload sets via
   DECL_NAME.  */

struct named_decl_hash : ggc_remove <tree> {
  typedef tree value_type; /* A DECL or OVERLOAD  */
  typedef tree compare_type; /* An identifier.  */

  inline static hashval_t hash (const value_type decl);
  inline static bool equal (const value_type existing, compare_type candidate);

  static const bool empty_zero_p = true;
  static inline void mark_empty (value_type &p) {p = NULL_TREE;}
  static inline bool is_empty (value_type p) {return !p;}

  /* Nothing is deletable.  Everything is insertable.  */
  static bool is_deleted (value_type) { return false; }
  static void mark_deleted (value_type) { gcc_unreachable (); }
};

/* Simplified unique_ptr clone to release a tree vec on exit.  */

class releasing_vec
{
public:
  typedef vec<tree, va_gc> vec_t;

  releasing_vec (vec_t *v): v(v) { }
  releasing_vec (): v(make_tree_vector ()) { }

  /* Copy ops are deliberately declared but not defined,
     copies must always be elided.  */
  releasing_vec (const releasing_vec &);
  releasing_vec &operator= (const releasing_vec &);

  vec_t &operator* () const { return *v; }
  vec_t *operator-> () const { return v; }
  vec_t *get() const { return v; }
  operator vec_t *() const { return v; }
  vec_t ** operator& () { return &v; }

  /* Breaks pointer/value consistency for convenience.  This takes ptrdiff_t
     rather than unsigned to avoid ambiguity with the built-in operator[]
     (bootstrap/91828).  */
  tree& operator[] (ptrdiff_t i) const { return (*v)[i]; }

  tree *begin() { return ::begin (v); }
  tree *end() { return ::end (v); }

  void release () { release_tree_vector (v); v = NULL; }

  ~releasing_vec () { release_tree_vector (v); }
private:
  vec_t *v;
};
/* Forwarding functions for vec_safe_* that might reallocate.  */
inline tree* vec_safe_push (releasing_vec& r, const tree &t CXX_MEM_STAT_INFO)
{ return vec_safe_push (*&r, t PASS_MEM_STAT); }
inline bool vec_safe_reserve (releasing_vec& r, unsigned n, bool e = false CXX_MEM_STAT_INFO)
{ return vec_safe_reserve (*&r, n, e PASS_MEM_STAT); }
inline unsigned vec_safe_length (releasing_vec &r)
{ return r->length(); }
inline void vec_safe_splice (releasing_vec &r, vec<tree, va_gc> *p CXX_MEM_STAT_INFO)
{ vec_safe_splice (*&r, p PASS_MEM_STAT); }
void release_tree_vector (releasing_vec &); // cause link error

struct GTY(()) tree_template_decl {
  struct tree_decl_common common;
  tree arguments;
  tree result;
};

/* Returns true iff NODE is a BASELINK.  */
#define BASELINK_P(NODE) \
  (TREE_CODE (NODE) == BASELINK)
/* The BINFO indicating the base in which lookup found the
   BASELINK_FUNCTIONS.  */
#define BASELINK_BINFO(NODE) \
  (((struct tree_baselink*) BASELINK_CHECK (NODE))->binfo)
/* The functions referred to by the BASELINK; either a FUNCTION_DECL,
   a TEMPLATE_DECL, an OVERLOAD, or a TEMPLATE_ID_EXPR.  */
#define BASELINK_FUNCTIONS(NODE) \
  (((struct tree_baselink*) BASELINK_CHECK (NODE))->functions)
/* If T is a BASELINK, grab the functions, otherwise just T, which is
   expected to already be a (list of) functions.  */
#define MAYBE_BASELINK_FUNCTIONS(T) \
  (BASELINK_P (T) ? BASELINK_FUNCTIONS (T) : T)
/* The BINFO in which the search for the functions indicated by this baselink
   began.  This base is used to determine the accessibility of functions
   selected by overload resolution.  */
#define BASELINK_ACCESS_BINFO(NODE) \
  (((struct tree_baselink*) BASELINK_CHECK (NODE))->access_binfo)
/* For a type-conversion operator, the BASELINK_OPTYPE indicates the type
   to which the conversion should occur.  This value is important if
   the BASELINK_FUNCTIONS include a template conversion operator --
   the BASELINK_OPTYPE can be used to determine what type the user
   requested.  */
#define BASELINK_OPTYPE(NODE) \
  (TREE_CHAIN (BASELINK_CHECK (NODE)))
/* Nonzero if this baselink was from a qualified lookup.  */
#define BASELINK_QUALIFIED_P(NODE) \
  TREE_LANG_FLAG_0 (BASELINK_CHECK (NODE))
/* Nonzero if the overload set for this baselink might be incomplete due
   to the lookup being performed from an incomplete-class context.  */
#define BASELINK_FUNCTIONS_MAYBE_INCOMPLETE_P(NODE) \
  TREE_LANG_FLAG_1 (BASELINK_CHECK (NODE))

struct GTY(()) tree_baselink {
  struct tree_common common;
  tree binfo;
  tree functions;
  tree access_binfo;
};

/* The different kinds of ids that we encounter.  */

enum cp_id_kind
{
  /* Not an id at all.  */
  CP_ID_KIND_NONE,
  /* An unqualified-id that is not a template-id.  */
  CP_ID_KIND_UNQUALIFIED,
  /* An unqualified-id that is a dependent name.  */
  CP_ID_KIND_UNQUALIFIED_DEPENDENT,
  /* An unqualified template-id.  */
  CP_ID_KIND_TEMPLATE_ID,
  /* A qualified-id.  */
  CP_ID_KIND_QUALIFIED
};


/* The various kinds of C++0x warnings we encounter. */

enum cpp0x_warn_str
{
  /* extended initializer lists */
  CPP0X_INITIALIZER_LISTS,
  /* explicit conversion operators */
  CPP0X_EXPLICIT_CONVERSION,
  /* variadic templates */
  CPP0X_VARIADIC_TEMPLATES,
  /* lambda expressions */
  CPP0X_LAMBDA_EXPR,
  /* C++0x auto */
  CPP0X_AUTO,
  /* scoped enums */
  CPP0X_SCOPED_ENUMS,
  /* defaulted and deleted functions */
  CPP0X_DEFAULTED_DELETED,
  /* inline namespaces */
  CPP0X_INLINE_NAMESPACES,
  /* override controls, override/final */
  CPP0X_OVERRIDE_CONTROLS,
  /* non-static data member initializers */
  CPP0X_NSDMI,
  /* user defined literals */
  CPP0X_USER_DEFINED_LITERALS,
  /* delegating constructors */
  CPP0X_DELEGATING_CTORS,
  /* inheriting constructors */
  CPP0X_INHERITING_CTORS,
  /* C++11 attributes */
  CPP0X_ATTRIBUTES,
  /* ref-qualified member functions */
  CPP0X_REF_QUALIFIER
};

/* The various kinds of operation used by composite_pointer_type. */

enum composite_pointer_operation
{
  /* comparison */
  CPO_COMPARISON,
  /* conversion */
  CPO_CONVERSION,
  /* conditional expression */
  CPO_CONDITIONAL_EXPR
};

/* Possible cases of expression list used by build_x_compound_expr_from_list. */
enum expr_list_kind {
  ELK_INIT,		/* initializer */
  ELK_MEM_INIT,		/* member initializer */
  ELK_FUNC_CAST		/* functional cast */
};

/* Possible cases of implicit bad rhs conversions. */
enum impl_conv_rhs {
  ICR_DEFAULT_ARGUMENT, /* default argument */
  ICR_CONVERTING,       /* converting */
  ICR_INIT,             /* initialization */
  ICR_ARGPASS,          /* argument passing */
  ICR_RETURN,           /* return */
  ICR_ASSIGN            /* assignment */
};

/* Possible cases of implicit or explicit bad conversions to void. */
enum impl_conv_void {
  ICV_CAST,            /* (explicit) conversion to void */
  ICV_SECOND_OF_COND,  /* second operand of conditional expression */
  ICV_THIRD_OF_COND,   /* third operand of conditional expression */
  ICV_RIGHT_OF_COMMA,  /* right operand of comma operator */
  ICV_LEFT_OF_COMMA,   /* left operand of comma operator */
  ICV_STATEMENT,       /* statement */
  ICV_THIRD_IN_FOR     /* for increment expression */
};

/* Possible invalid uses of an abstract class that might not have a
   specific associated declaration.  */
enum GTY(()) abstract_class_use {
  ACU_UNKNOWN,			/* unknown or decl provided */
  ACU_CAST,			/* cast to abstract class */
  ACU_NEW,			/* new-expression of abstract class */
  ACU_THROW,			/* throw-expression of abstract class */
  ACU_CATCH,			/* catch-parameter of abstract class */
  ACU_ARRAY,			/* array of abstract class */
  ACU_RETURN,			/* return type of abstract class */
  ACU_PARM			/* parameter type of abstract class */
};

/* Macros for access to language-specific slots in an identifier.  */

/* Identifiers map directly to block or class-scope bindings.
   Namespace-scope bindings are held in hash tables on the respective
   namespaces.  The identifier bindings are the innermost active
   binding, from whence you can get the decl and/or implicit-typedef
   of an elaborated type.   When not bound to a local entity the
   values are NULL.  */
#define IDENTIFIER_BINDING(NODE) \
  (LANG_IDENTIFIER_CAST (NODE)->bindings)
#define REAL_IDENTIFIER_TYPE_VALUE(NODE) TREE_TYPE (NODE)
#define SET_IDENTIFIER_TYPE_VALUE(NODE,TYPE) (TREE_TYPE (NODE) = (TYPE))

/* Kinds of identifiers.  Values are carefully chosen.  */
enum cp_identifier_kind {
  cik_normal = 0,	/* Not a special identifier.  */
  cik_keyword = 1,	/* A keyword.  */
  cik_ctor = 2,		/* Constructor (in-chg, complete or base).  */
  cik_dtor = 3,		/* Destructor (in-chg, deleting, complete or
			   base).  */
  cik_simple_op = 4,	/* Non-assignment operator name.  */
  cik_assign_op = 5,	/* An assignment operator name.  */
  cik_conv_op = 6,	/* Conversion operator name.  */
  cik_reserved_for_udlit = 7,	/* Not yet in use  */
  cik_max
};

/* Kind bits.  */
#define IDENTIFIER_KIND_BIT_0(NODE) \
  TREE_LANG_FLAG_0 (IDENTIFIER_NODE_CHECK (NODE))
#define IDENTIFIER_KIND_BIT_1(NODE) \
  TREE_LANG_FLAG_1 (IDENTIFIER_NODE_CHECK (NODE))
#define IDENTIFIER_KIND_BIT_2(NODE) \
  TREE_LANG_FLAG_2 (IDENTIFIER_NODE_CHECK (NODE))

/* Used by various search routines.  */
#define IDENTIFIER_MARKED(NODE) \
  TREE_LANG_FLAG_4 (IDENTIFIER_NODE_CHECK (NODE))

/* Nonzero if this identifier is used as a virtual function name somewhere
   (optimizes searches).  */
#define IDENTIFIER_VIRTUAL_P(NODE) \
  TREE_LANG_FLAG_5 (IDENTIFIER_NODE_CHECK (NODE))

/* True if this identifier is a reserved word.  C_RID_CODE (node) is
   then the RID_* value of the keyword.  Value 1.  */
#define IDENTIFIER_KEYWORD_P(NODE)		\
  ((!IDENTIFIER_KIND_BIT_2 (NODE))		\
   & (!IDENTIFIER_KIND_BIT_1 (NODE))		\
   & IDENTIFIER_KIND_BIT_0 (NODE))

/* True if this identifier is the name of a constructor or
   destructor.  Value 2 or 3.  */
#define IDENTIFIER_CDTOR_P(NODE)		\
  ((!IDENTIFIER_KIND_BIT_2 (NODE))		\
   & IDENTIFIER_KIND_BIT_1 (NODE))

/* True if this identifier is the name of a constructor.  Value 2.  */
#define IDENTIFIER_CTOR_P(NODE)			\
  (IDENTIFIER_CDTOR_P(NODE)			\
    & (!IDENTIFIER_KIND_BIT_0 (NODE)))

/* True if this identifier is the name of a destructor.  Value 3.  */
#define IDENTIFIER_DTOR_P(NODE)			\
  (IDENTIFIER_CDTOR_P(NODE)			\
    & IDENTIFIER_KIND_BIT_0 (NODE))

/* True if this identifier is for any operator name (including
   conversions).  Value 4, 5, 6 or 7.  */
#define IDENTIFIER_ANY_OP_P(NODE)		\
  (IDENTIFIER_KIND_BIT_2 (NODE))

/* True if this identifier is for an overloaded operator. Values 4, 5.  */
#define IDENTIFIER_OVL_OP_P(NODE)		\
  (IDENTIFIER_ANY_OP_P (NODE)			\
   & (!IDENTIFIER_KIND_BIT_1 (NODE)))

/* True if this identifier is for any assignment. Values 5.  */
#define IDENTIFIER_ASSIGN_OP_P(NODE)		\
  (IDENTIFIER_OVL_OP_P (NODE)			\
   & IDENTIFIER_KIND_BIT_0 (NODE))

/* True if this identifier is the name of a type-conversion
   operator.  Value 7.  */
#define IDENTIFIER_CONV_OP_P(NODE)		\
  (IDENTIFIER_ANY_OP_P (NODE)			\
   & IDENTIFIER_KIND_BIT_1 (NODE)		\
   & (!IDENTIFIER_KIND_BIT_0 (NODE)))

/* True if this identifier is a new or delete operator.  */
#define IDENTIFIER_NEWDEL_OP_P(NODE)		\
  (IDENTIFIER_OVL_OP_P (NODE)			\
   && IDENTIFIER_OVL_OP_FLAGS (NODE) & OVL_OP_FLAG_ALLOC)

/* True if this identifier is a new operator.  */
#define IDENTIFIER_NEW_OP_P(NODE)					\
  (IDENTIFIER_OVL_OP_P (NODE)						\
   && (IDENTIFIER_OVL_OP_FLAGS (NODE)					\
       & (OVL_OP_FLAG_ALLOC | OVL_OP_FLAG_DELETE)) == OVL_OP_FLAG_ALLOC)

/* Access a C++-specific index for identifier NODE.
   Used to optimize operator mappings etc.  */
#define IDENTIFIER_CP_INDEX(NODE)		\
  (IDENTIFIER_NODE_CHECK(NODE)->base.u.bits.address_space)

/* In a RECORD_TYPE or UNION_TYPE, nonzero if any component is read-only.  */
#define C_TYPE_FIELDS_READONLY(TYPE) \
  (LANG_TYPE_CLASS_CHECK (TYPE)->fields_readonly)

/* The tokens stored in the unparsed operand.  */

#define DEFPARSE_TOKENS(NODE) \
  (((struct tree_deferred_parse *)DEFERRED_PARSE_CHECK (NODE))->tokens)
#define DEFPARSE_INSTANTIATIONS(NODE) \
  (((struct tree_deferred_parse *)DEFERRED_PARSE_CHECK (NODE))->instantiations)

struct GTY (()) tree_deferred_parse {
  struct tree_base base;
  struct cp_token_cache *tokens;
  vec<tree, va_gc> *instantiations;
};


#define DEFERRED_NOEXCEPT_PATTERN(NODE) \
  (((struct tree_deferred_noexcept *)DEFERRED_NOEXCEPT_CHECK (NODE))->pattern)
#define DEFERRED_NOEXCEPT_ARGS(NODE) \
  (((struct tree_deferred_noexcept *)DEFERRED_NOEXCEPT_CHECK (NODE))->args)
#define DEFERRED_NOEXCEPT_SPEC_P(NODE)				\
  ((NODE) && (TREE_PURPOSE (NODE))				\
   && (TREE_CODE (TREE_PURPOSE (NODE)) == DEFERRED_NOEXCEPT))
#define UNEVALUATED_NOEXCEPT_SPEC_P(NODE)				\
  (DEFERRED_NOEXCEPT_SPEC_P (NODE)					\
   && DEFERRED_NOEXCEPT_PATTERN (TREE_PURPOSE (NODE)) == NULL_TREE)
#define UNPARSED_NOEXCEPT_SPEC_P(NODE) \
  ((NODE) && (TREE_PURPOSE (NODE)) \
   && (TREE_CODE (TREE_PURPOSE (NODE)) == DEFERRED_PARSE))

struct GTY (()) tree_deferred_noexcept {
  struct tree_base base;
  tree pattern;
  tree args;
};


/* The condition associated with the static assertion.  This must be
   an integral constant expression.  */
#define STATIC_ASSERT_CONDITION(NODE) \
  (((struct tree_static_assert *)STATIC_ASSERT_CHECK (NODE))->condition)

/* The message associated with the static assertion.  This must be a
   string constant, which will be emitted as an error message when the
   static assert condition is false.  */
#define STATIC_ASSERT_MESSAGE(NODE) \
  (((struct tree_static_assert *)STATIC_ASSERT_CHECK (NODE))->message)

/* Source location information for a static assertion.  */
#define STATIC_ASSERT_SOURCE_LOCATION(NODE) \
  (((struct tree_static_assert *)STATIC_ASSERT_CHECK (NODE))->location)

struct GTY (()) tree_static_assert {
  struct tree_common common;
  tree condition;
  tree message;
  location_t location;
};

struct GTY (()) tree_argument_pack_select {
  struct tree_common common;
  tree argument_pack;
  int index;
};

/* The different kinds of traits that we encounter.  */

enum cp_trait_kind
{
#define DEFTRAIT(TCC, CODE, NAME, ARITY) \
  CPTK_##CODE,
#include "cp-trait.def"
#undef DEFTRAIT
};

/* The types that we are processing.  */
#define TRAIT_EXPR_TYPE1(NODE) \
  (((struct tree_trait_expr *)TRAIT_EXPR_CHECK (NODE))->type1)

#define TRAIT_EXPR_TYPE2(NODE) \
  (((struct tree_trait_expr *)TRAIT_EXPR_CHECK (NODE))->type2)

/* The specific trait that we are processing.  */
#define TRAIT_EXPR_KIND(NODE) \
  (((struct tree_trait_expr *)TRAIT_EXPR_CHECK (NODE))->kind)

#define TRAIT_EXPR_LOCATION(NODE) \
  (((struct tree_trait_expr *)TRAIT_EXPR_CHECK (NODE))->locus)

struct GTY (()) tree_trait_expr {
  struct tree_common common;
  tree type1;
  tree type2;
  location_t locus;
  enum cp_trait_kind kind;
};

/* An INTEGER_CST containing the kind of the trait type NODE.  */
#define TRAIT_TYPE_KIND_RAW(NODE) \
  TYPE_VALUES_RAW (TRAIT_TYPE_CHECK (NODE))

/* The kind of the trait type NODE.  */
#define TRAIT_TYPE_KIND(NODE) \
  ((enum cp_trait_kind) TREE_INT_CST_LOW (TRAIT_TYPE_KIND_RAW (NODE)))

/* The first argument of the trait type NODE.  */
#define TRAIT_TYPE_TYPE1(NODE) \
  TYPE_MIN_VALUE_RAW (TRAIT_TYPE_CHECK (NODE))

/* The rest of the arguments of the trait type NODE.  */
#define TRAIT_TYPE_TYPE2(NODE) \
  TYPE_MAX_VALUE_RAW (TRAIT_TYPE_CHECK (NODE))

/* Identifiers used for lambda types are almost anonymous.  Use this
   spare flag to distinguish them (they also have the anonymous flag).  */
#define IDENTIFIER_LAMBDA_P(NODE) \
  (IDENTIFIER_NODE_CHECK(NODE)->base.protected_flag)

/* Based off of TYPE_UNNAMED_P.  */
#define LAMBDA_TYPE_P(NODE)					\
  (TREE_CODE (NODE) == RECORD_TYPE				\
   && TYPE_LINKAGE_IDENTIFIER (NODE)				\
   && IDENTIFIER_LAMBDA_P (TYPE_LINKAGE_IDENTIFIER (NODE)))

/* Test if FUNCTION_DECL is a lambda function.  */
#define LAMBDA_FUNCTION_P(FNDECL)				\
  (DECL_DECLARES_FUNCTION_P (FNDECL)				\
   && DECL_OVERLOADED_OPERATOR_P (FNDECL)			\
   && DECL_OVERLOADED_OPERATOR_IS (FNDECL, CALL_EXPR)		\
   && LAMBDA_TYPE_P (CP_DECL_CONTEXT (FNDECL)))

enum cp_lambda_default_capture_mode_type {
  CPLD_NONE,
  CPLD_COPY,
  CPLD_REFERENCE
};

/* The method of default capture, if any.  */
#define LAMBDA_EXPR_DEFAULT_CAPTURE_MODE(NODE) \
  (((struct tree_lambda_expr *)LAMBDA_EXPR_CHECK (NODE))->default_capture_mode)

/* The capture-list, including `this'.  Each capture is stored as a FIELD_DECL
 * so that the name, type, and field are all together, whether or not it has
 * been added to the lambda's class type.
   TREE_LIST:
     TREE_PURPOSE: The FIELD_DECL for this capture.
     TREE_VALUE: The initializer. This is part of a GNU extension.  */
#define LAMBDA_EXPR_CAPTURE_LIST(NODE) \
  (((struct tree_lambda_expr *)LAMBDA_EXPR_CHECK (NODE))->capture_list)

/* During parsing of the lambda-introducer, the node in the capture-list
   that holds the 'this' capture.  During parsing of the body, the
   capture proxy for that node.  */
#define LAMBDA_EXPR_THIS_CAPTURE(NODE) \
  (((struct tree_lambda_expr *)LAMBDA_EXPR_CHECK (NODE))->this_capture)

/* Predicate tracking whether `this' is in the effective capture set.  */
#define LAMBDA_EXPR_CAPTURES_THIS_P(NODE) \
  LAMBDA_EXPR_THIS_CAPTURE(NODE)

/* Predicate tracking whether the lambda was declared 'mutable'.  */
#define LAMBDA_EXPR_MUTABLE_P(NODE) \
  TREE_LANG_FLAG_1 (LAMBDA_EXPR_CHECK (NODE))

/* True iff uses of a const variable capture were optimized away.  */
#define LAMBDA_EXPR_CAPTURE_OPTIMIZED(NODE) \
  TREE_LANG_FLAG_2 (LAMBDA_EXPR_CHECK (NODE))

/* Predicate tracking whether the lambda was declared 'static'.  */
#define LAMBDA_EXPR_STATIC_P(NODE) \
  TREE_LANG_FLAG_3 (LAMBDA_EXPR_CHECK (NODE))

/* True if this TREE_LIST in LAMBDA_EXPR_CAPTURE_LIST is for an explicit
   capture.  */
#define LAMBDA_CAPTURE_EXPLICIT_P(NODE) \
  TREE_LANG_FLAG_0 (TREE_LIST_CHECK (NODE))

/* The source location of the lambda.  */
#define LAMBDA_EXPR_LOCATION(NODE) \
  (((struct tree_lambda_expr *)LAMBDA_EXPR_CHECK (NODE))->locus)

/* The mangling scope for the lambda: FUNCTION_DECL, PARM_DECL, VAR_DECL,
   FIELD_DECL or NULL_TREE.  If this is NULL_TREE, we have no linkage.  */
#define LAMBDA_EXPR_EXTRA_SCOPE(NODE) \
  (((struct tree_lambda_expr *)LAMBDA_EXPR_CHECK (NODE))->extra_scope)

/* Lambdas in the same extra scope might need a discriminating count.
   For ABI 17, we have single per-scope count, for ABI 18, we have
   per-scope, per-signature numbering.  */
#define LAMBDA_EXPR_SCOPE_ONLY_DISCRIMINATOR(NODE) \
  (((struct tree_lambda_expr *)LAMBDA_EXPR_CHECK (NODE))->discriminator_scope)
#define LAMBDA_EXPR_SCOPE_SIG_DISCRIMINATOR(NODE) \
  (((struct tree_lambda_expr *)LAMBDA_EXPR_CHECK (NODE))->discriminator_sig)

/* During parsing of the lambda, a vector of capture proxies which need
   to be pushed once we're done processing a nested lambda.  */
#define LAMBDA_EXPR_PENDING_PROXIES(NODE) \
  (((struct tree_lambda_expr *)LAMBDA_EXPR_CHECK (NODE))->pending_proxies)

/* If NODE was regenerated via tsubst_lambda_expr, this is a TEMPLATE_INFO
   whose TI_TEMPLATE is the immediate LAMBDA_EXPR from which NODE was
   regenerated, and TI_ARGS is the full set of template arguments used
   to regenerate NODE from the most general lambda.  */
#define LAMBDA_EXPR_REGEN_INFO(NODE) \
  (((struct tree_lambda_expr *)LAMBDA_EXPR_CHECK (NODE))->regen_info)

/* The closure type of the lambda, which is also the type of the
   LAMBDA_EXPR.  */
#define LAMBDA_EXPR_CLOSURE(NODE) \
  (TREE_TYPE (LAMBDA_EXPR_CHECK (NODE)))

struct GTY (()) tree_lambda_expr
{
  struct tree_typed typed;
  tree capture_list;
  tree this_capture;
  tree extra_scope;
  tree regen_info;
  vec<tree, va_gc> *pending_proxies;
  location_t locus;
  enum cp_lambda_default_capture_mode_type default_capture_mode : 2;
  unsigned discriminator_scope : 15; // Per-scope discriminator
  unsigned discriminator_sig : 15; // Per-scope, per-signature discriminator
};

/* Non-zero if this template specialization has access violations that
   should be rechecked when the function is instantiated outside argument
   deduction.  */
#define TINFO_HAS_ACCESS_ERRORS(NODE) \
  (TREE_LANG_FLAG_0 (TEMPLATE_INFO_CHECK (NODE)))
#define FNDECL_HAS_ACCESS_ERRORS(NODE) \
  (TINFO_HAS_ACCESS_ERRORS (DECL_TEMPLATE_INFO (NODE)))

/* Non-zero if this variable template specialization was specified using a
   template-id, so it's a partial or full specialization and not a definition
   of the member template of a particular class specialization.  */
#define TINFO_USED_TEMPLATE_ID(NODE) \
  (TREE_LANG_FLAG_1 (TEMPLATE_INFO_CHECK (NODE)))

/* The representation of a deferred access check.  */

struct GTY(()) deferred_access_check {
  /* The base class in which the declaration is referenced. */
  tree binfo;
  /* The declaration whose access must be checked.  */
  tree decl;
  /* The declaration that should be used in the error message.  */
  tree diag_decl;
  /* The location of this access.  */
  location_t loc;
};

struct GTY(()) tree_template_info {
  struct tree_base base;
  tree tmpl;
  tree args;
  vec<deferred_access_check, va_gc> *deferred_access_checks;
};

// Constraint information for a C++ declaration. Constraint information is
// comprised of:
//
// - a constraint expression introduced by the template header
// - a constraint expression introduced by a function declarator
// - the associated constraints, which are the conjunction of those,
//   and used for declaration matching
//
// The template and declarator requirements are kept to support pretty
// printing constrained declarations.
struct GTY(()) tree_constraint_info {
  struct tree_base base;
  tree template_reqs;
  tree declarator_reqs;
  tree associated_constr;
};

// Require that pointer P is non-null before returning.
template<typename T>
inline T*
check_nonnull (T* p)
{
  gcc_assert (p);
  return p;
}

/* Returns true iff T is non-null and represents constraint info.  */
inline tree_constraint_info *
check_constraint_info (tree t)
{
  if (t && TREE_CODE (t) == CONSTRAINT_INFO)
    return (tree_constraint_info *)t;
  return NULL;
}

/* Access the expression describing the template constraints. This may be
   null if no constraints were introduced in the template parameter list,
   a requirements clause after the template parameter list, or constraints
   through a constrained-type-specifier.  */
#define CI_TEMPLATE_REQS(NODE) \
  check_constraint_info (check_nonnull (NODE))->template_reqs

/* Access the expression describing the trailing constraints. This is non-null
   for any implicit instantiation of a constrained declaration. For a
   templated declaration it is non-null only when a trailing requires-clause
   was specified.  */
#define CI_DECLARATOR_REQS(NODE) \
  check_constraint_info (check_nonnull (NODE))->declarator_reqs

/* The computed associated constraint expression for a declaration.  */
#define CI_ASSOCIATED_CONSTRAINTS(NODE) \
  check_constraint_info (check_nonnull (NODE))->associated_constr

/* Access the constraint-expression introduced by the requires-clause
   associate the template parameter list NODE.  */
#define TEMPLATE_PARMS_CONSTRAINTS(NODE) \
  TREE_TYPE (TREE_LIST_CHECK (NODE))

/* Access the logical constraints on the template parameter declaration
   indicated by NODE.  */
#define TEMPLATE_PARM_CONSTRAINTS(NODE) \
  TREE_TYPE (TREE_LIST_CHECK (NODE))

/* Non-zero if the noexcept is present in a compound requirement.  */
#define COMPOUND_REQ_NOEXCEPT_P(NODE) \
  TREE_LANG_FLAG_0 (TREE_CHECK (NODE, COMPOUND_REQ))

/* A TREE_LIST whose TREE_VALUE is the constraints on the 'auto' placeholder
   type NODE, used in an argument deduction constraint.  The TREE_PURPOSE
   holds the set of template parameters that were in-scope when this 'auto'
   was formed.  */
#define PLACEHOLDER_TYPE_CONSTRAINTS_INFO(NODE) \
  DECL_SIZE_UNIT (TYPE_NAME (NODE))

/* The constraints on the 'auto' placeholder type NODE.  */
#define PLACEHOLDER_TYPE_CONSTRAINTS(NODE)		   \
  (PLACEHOLDER_TYPE_CONSTRAINTS_INFO (NODE)		   \
   ? TREE_VALUE (PLACEHOLDER_TYPE_CONSTRAINTS_INFO (NODE)) \
   : NULL_TREE)

/* True if NODE is a constraint.  */
#define CONSTR_P(NODE)                  \
  (TREE_CODE (NODE) == ATOMIC_CONSTR    \
   || TREE_CODE (NODE) == CONJ_CONSTR   \
   || TREE_CODE (NODE) == DISJ_CONSTR)

/* Valid for any normalized constraint.  */
#define CONSTR_CHECK(NODE) \
  TREE_CHECK3 (NODE, ATOMIC_CONSTR, CONJ_CONSTR, DISJ_CONSTR)

/* The CONSTR_INFO stores normalization data for a constraint. It refers to
   the original expression and the expression or declaration
   from which the constraint was normalized.

   This is TREE_LIST whose TREE_PURPOSE is the original expression and whose
   TREE_VALUE is a list of contexts.  */
#define CONSTR_INFO(NODE) \
  TREE_TYPE (CONSTR_CHECK (NODE))

/* The expression evaluated by the constraint.  */
#define CONSTR_EXPR(NODE) \
  TREE_PURPOSE (CONSTR_INFO (NODE))

/* The expression or declaration from which this constraint was normalized.
   This is a TREE_LIST whose TREE_VALUE is either a template-id expression
   denoting a concept check or the declaration introducing the constraint.
   These are chained to other context objects.  */
#define CONSTR_CONTEXT(NODE) \
  TREE_VALUE (CONSTR_INFO (NODE))

/* The parameter mapping for an atomic constraint. */
#define ATOMIC_CONSTR_MAP(NODE) \
  TREE_OPERAND (TREE_CHECK (NODE, ATOMIC_CONSTR), 0)

/* Whether the parameter mapping of this atomic constraint
   is already instantiated with concrete template arguments.
   Used only in satisfy_atom and in the satisfaction cache.  */
#define ATOMIC_CONSTR_MAP_INSTANTIATED_P(NODE) \
  TREE_LANG_FLAG_0 (ATOMIC_CONSTR_CHECK (NODE))

/* Whether the expression for this atomic constraint belongs to a
   concept definition.  */
#define ATOMIC_CONSTR_EXPR_FROM_CONCEPT_P(NODE) \
  TREE_LANG_FLAG_1 (ATOMIC_CONSTR_CHECK (NODE))

/* The expression of an atomic constraint. */
#define ATOMIC_CONSTR_EXPR(NODE) \
  CONSTR_EXPR (ATOMIC_CONSTR_CHECK (NODE))

/* The concept of a concept check. */
#define CHECK_CONSTR_CONCEPT(NODE) \
  TREE_OPERAND (TREE_CHECK (NODE, CHECK_CONSTR), 0)

/* The template arguments of a concept check. */
#define CHECK_CONSTR_ARGS(NODE) \
  TREE_OPERAND (TREE_CHECK (NODE, CHECK_CONSTR), 1)

/* Whether a PARM_DECL represents a local parameter in a
   requires-expression.  */
#define CONSTRAINT_VAR_P(NODE) \
  DECL_LANG_FLAG_2 (TREE_CHECK (NODE, PARM_DECL))

/* The concept constraining this constrained template-parameter.  */
#define CONSTRAINED_PARM_CONCEPT(NODE) \
  DECL_SIZE_UNIT (TYPE_DECL_CHECK (NODE))
/* Any extra template arguments specified for a constrained
   template-parameter.  */
#define CONSTRAINED_PARM_EXTRA_ARGS(NODE) \
  DECL_SIZE (TYPE_DECL_CHECK (NODE))
/* The first template parameter of CONSTRAINED_PARM_CONCEPT to be used as a
   prototype for the constrained parameter in finish_shorthand_constraint,
   attached for convenience.  */
#define CONSTRAINED_PARM_PROTOTYPE(NODE) \
  DECL_INITIAL (TYPE_DECL_CHECK (NODE))

/* Module flags on FUNCTION,VAR,TYPE,CONCEPT or NAMESPACE
   A TEMPLATE_DECL holds them on the DECL_TEMPLATE_RESULT object --
   it's just not practical to keep them consistent.  */
#define DECL_MODULE_CHECK(NODE)						\
  TREE_NOT_CHECK (NODE, TEMPLATE_DECL)

/* In the purview of a named module (or in the purview of the
   header-unit being compiled).  */
#define DECL_MODULE_PURVIEW_P(N) \
  (DECL_LANG_SPECIFIC (DECL_MODULE_CHECK (N))->u.base.module_purview_p)

/* Attached to the named module it is in the purview of.  Decls
   attached to the global module will have this false.  */
#define DECL_MODULE_ATTACH_P(N) \
  (DECL_LANG_SPECIFIC (DECL_MODULE_CHECK (N))->u.base.module_attach_p)

/* True if the live version of the decl was imported.  */
#define DECL_MODULE_IMPORT_P(NODE) \
  (DECL_LANG_SPECIFIC (DECL_MODULE_CHECK (NODE))->u.base.module_import_p)

/* True if this decl is in the entity hash & array.  This means that
   some variant was imported, even if DECL_MODULE_IMPORT_P is false.  */
#define DECL_MODULE_ENTITY_P(NODE) \
  (DECL_LANG_SPECIFIC (DECL_MODULE_CHECK (NODE))->u.base.module_entity_p)

/* DECL that has attached decls for ODR-relatedness.  */
#define DECL_MODULE_KEYED_DECLS_P(NODE)			\
  (DECL_LANG_SPECIFIC (TREE_CHECK2(NODE,FUNCTION_DECL,VAR_DECL))\
   ->u.base.module_keyed_decls_p)

/* Whether this is an exported DECL.  Held on any decl that can appear
   at namespace scope (function, var, type, template, const or
   namespace).  templates copy from their template_result, consts have
   it for unscoped enums.  */
#define DECL_MODULE_EXPORT_P(NODE) TREE_LANG_FLAG_3 (NODE)