/* Definitions for CPP library.
   Copyright (C) 1995-2024 Free Software Foundation, Inc.
   Written by Per Bothner, 1994-95.

This program is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation; either version 3, or (at your option) any
later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; see the file COPYING3.  If not see
<http://www.gnu.org/licenses/>.

 In other words, you are welcome to use, share and improve this program.
 You are forbidden to forbid anyone else to use, share and improve
 what you give them.   Help stamp out software-hoarding!  */
#ifndef LIBCPP_CPPLIB_H
#define LIBCPP_CPPLIB_H

#include <sys/types.h>
#include "symtab.h"
#include "line-map.h"

typedef struct cpp_reader cpp_reader;
typedef struct cpp_buffer cpp_buffer;
typedef struct cpp_options cpp_options;
typedef struct cpp_token cpp_token;
typedef struct cpp_string cpp_string;
typedef struct cpp_hashnode cpp_hashnode;
typedef struct cpp_macro cpp_macro;
typedef struct cpp_callbacks cpp_callbacks;
typedef struct cpp_dir cpp_dir;

struct _cpp_file;

class rich_location;

/* The first three groups, apart from '=', can appear in preprocessor
   expressions (+= and -= are used to indicate unary + and - resp.).
   This allows a lookup table to be implemented in _cpp_parse_expr.

   The first group, to CPP_LAST_EQ, can be immediately followed by an
   '='.  The lexer needs operators ending in '=', like ">>=", to be in
   the same order as their counterparts without the '=', like ">>".

   See the cpp_operator table optab in expr.cc if you change the order or
   add or remove anything in the first group.  */

#define TTYPE_TABLE							\
  OP(EQ,		"=")						\
  OP(NOT,		"!")						\
  OP(GREATER,		">")	/* compare */				\
  OP(LESS,		"<")						\
  OP(PLUS,		"+")	/* math */				\
  OP(MINUS,		"-")						\
  OP(MULT,		"*")						\
  OP(DIV,		"/")						\
  OP(MOD,		"%")						\
  OP(AND,		"&")	/* bit ops */				\
  OP(OR,		"|")						\
  OP(XOR,		"^")						\
  OP(RSHIFT,		">>")						\
  OP(LSHIFT,		"<<")						\
									\
  OP(COMPL,		"~")						\
  OP(AND_AND,		"&&")	/* logical */				\
  OP(OR_OR,		"||")						\
  OP(QUERY,		"?")						\
  OP(COLON,		":")						\
  OP(COMMA,		",")	/* grouping */				\
  OP(OPEN_PAREN,	"(")						\
  OP(CLOSE_PAREN,	")")						\
  TK(EOF,		NONE)						\
  OP(EQ_EQ,		"==")	/* compare */				\
  OP(NOT_EQ,		"!=")						\
  OP(GREATER_EQ,	">=")						\
  OP(LESS_EQ,		"<=")						\
  OP(SPACESHIP,		"<=>")						\
									\
  /* These two are unary + / - in preprocessor expressions.  */		\
  OP(PLUS_EQ,		"+=")	/* math */				\
  OP(MINUS_EQ,		"-=")						\
									\
  OP(MULT_EQ,		"*=")						\
  OP(DIV_EQ,		"/=")						\
  OP(MOD_EQ,		"%=")						\
  OP(AND_EQ,		"&=")	/* bit ops */				\
  OP(OR_EQ,		"|=")						\
  OP(XOR_EQ,		"^=")						\
  OP(RSHIFT_EQ,		">>=")						\
  OP(LSHIFT_EQ,		"<<=")						\
  /* Digraphs together, beginning with CPP_FIRST_DIGRAPH.  */		\
  OP(HASH,		"#")	/* digraphs */				\
  OP(PASTE,		"##")						\
  OP(OPEN_SQUARE,	"[")						\
  OP(CLOSE_SQUARE,	"]")						\
  OP(OPEN_BRACE,	"{")						\
  OP(CLOSE_BRACE,	"}")						\
  /* The remainder of the punctuation.	Order is not significant.  */	\
  OP(SEMICOLON,		";")	/* structure */				\
  OP(ELLIPSIS,		"...")						\
  OP(PLUS_PLUS,		"++")	/* increment */				\
  OP(MINUS_MINUS,	"--")						\
  OP(DEREF,		"->")	/* accessors */				\
  OP(DOT,		".")						\
  OP(SCOPE,		"::")						\
  OP(DEREF_STAR,	"->*")						\
  OP(DOT_STAR,		".*")						\
  OP(ATSIGN,		"@")  /* used in Objective-C */			\
									\
  TK(NAME,		IDENT)	 /* word */				\
  TK(AT_NAME,		IDENT)	 /* @word - Objective-C */		\
  TK(NUMBER,		LITERAL) /* 34_be+ta  */			\
									\
  TK(CHAR,		LITERAL) /* 'char' */				\
  TK(WCHAR,		LITERAL) /* L'char' */				\
  TK(CHAR16,		LITERAL) /* u'char' */				\
  TK(CHAR32,		LITERAL) /* U'char' */				\
  TK(UTF8CHAR,		LITERAL) /* u8'char' */				\
  TK(OTHER,		LITERAL) /* stray punctuation */		\
									\
  TK(STRING,		LITERAL) /* "string" */				\
  TK(WSTRING,		LITERAL) /* L"string" */			\
  TK(STRING16,		LITERAL) /* u"string" */			\
  TK(STRING32,		LITERAL) /* U"string" */			\
  TK(UTF8STRING,	LITERAL) /* u8"string" */			\
  TK(OBJC_STRING,	LITERAL) /* @"string" - Objective-C */		\
  TK(HEADER_NAME,	LITERAL) /* <stdio.h> in #include */		\
  TK(UNEVAL_STRING,	LITERAL) /* unevaluated "string" - C++26 */	\
									\
  TK(CHAR_USERDEF,	LITERAL) /* 'char'_suffix - C++11 */		\
  TK(WCHAR_USERDEF,	LITERAL) /* L'char'_suffix - C++11 */		\
  TK(CHAR16_USERDEF,	LITERAL) /* u'char'_suffix - C++11 */		\
  TK(CHAR32_USERDEF,	LITERAL) /* U'char'_suffix - C++11 */		\
  TK(UTF8CHAR_USERDEF,	LITERAL) /* u8'char'_suffix - C++11 */		\
  TK(STRING_USERDEF,	LITERAL) /* "string"_suffix - C++11 */		\
  TK(WSTRING_USERDEF,	LITERAL) /* L"string"_suffix - C++11 */		\
  TK(STRING16_USERDEF,	LITERAL) /* u"string"_suffix - C++11 */		\
  TK(STRING32_USERDEF,	LITERAL) /* U"string"_suffix - C++11 */		\
  TK(UTF8STRING_USERDEF,LITERAL) /* u8"string"_suffix - C++11 */	\
									\
  TK(EMBED,		LITERAL) /* #embed - C23 */			\
									\
  TK(COMMENT,		LITERAL) /* Only if output comments.  */	\
				 /* SPELL_LITERAL happens to DTRT.  */	\
  TK(MACRO_ARG,		NONE)	 /* Macro argument.  */			\
  TK(PRAGMA,		NONE)	 /* Only for deferred pragmas.  */	\
  TK(PRAGMA_EOL,	NONE)	 /* End-of-line for deferred pragmas.  */ \
  TK(PADDING,		NONE)	 /* Whitespace for -E.	*/

#define OP(e, s) CPP_ ## e,
#define TK(e, s) CPP_ ## e,
enum cpp_ttype
{
  TTYPE_TABLE
  N_TTYPES,

  /* A token type for keywords, as opposed to ordinary identifiers.  */
  CPP_KEYWORD,

  /* Positions in the table.  */
  CPP_LAST_EQ        = CPP_LSHIFT,
  CPP_FIRST_DIGRAPH  = CPP_HASH,
  CPP_LAST_PUNCTUATOR= CPP_ATSIGN,
  CPP_LAST_CPP_OP    = CPP_LESS_EQ
};
#undef OP
#undef TK

/* C language kind, used when calling cpp_create_reader.  */
enum c_lang {CLK_GNUC89 = 0, CLK_GNUC99, CLK_GNUC11, CLK_GNUC17, CLK_GNUC23,
	     CLK_GNUC2Y,
	     CLK_STDC89, CLK_STDC94, CLK_STDC99, CLK_STDC11, CLK_STDC17,
	     CLK_STDC23, CLK_STDC2Y,
	     CLK_GNUCXX, CLK_CXX98, CLK_GNUCXX11, CLK_CXX11,
	     CLK_GNUCXX14, CLK_CXX14, CLK_GNUCXX17, CLK_CXX17,
	     CLK_GNUCXX20, CLK_CXX20, CLK_GNUCXX23, CLK_CXX23,
	     CLK_GNUCXX26, CLK_CXX26, CLK_ASM};

/* Payload of a NUMBER, STRING, CHAR or COMMENT token.  */
struct GTY(()) cpp_string {
  unsigned int len;

  /* TEXT is always null terminated (terminator not included in len); but this
     GTY markup arranges that PCH streaming works properly even if there is a
     null byte in the middle of the string.  */
  const unsigned char * GTY((string_length ("1 + %h.len"))) text;
};

/* Flags for the cpp_token structure.  */
#define PREV_WHITE	(1 << 0) /* If whitespace before this token.  */
#define DIGRAPH		(1 << 1) /* If it was a digraph.  */
#define STRINGIFY_ARG	(1 << 2) /* If macro argument to be stringified.  */
#define PASTE_LEFT	(1 << 3) /* If on LHS of a ## operator.  */
#define NAMED_OP	(1 << 4) /* C++ named operators.  */
#define PREV_FALLTHROUGH (1 << 5) /* On a token preceeded by FALLTHROUGH
				     comment.  */
#define DECIMAL_INT     (1 << 6) /* Decimal integer, set in c-lex.cc.  */
#define PURE_ZERO	(1 << 7) /* Single 0 digit, used by the C++ frontend,
				    set in c-lex.cc.  */
#define COLON_SCOPE	PURE_ZERO /* Adjacent colons in C < 23.  */
#define NO_DOT_COLON	PURE_ZERO /* Set on CPP_NAME tokens whose expansion
				     shouldn't start with CPP_DOT or CPP_COLON
				     after optional CPP_PADDING.  */
#define SP_DIGRAPH	(1 << 8) /* # or ## token was a digraph.  */
#define SP_PREV_WHITE	(1 << 9) /* If whitespace before a ##
				    operator, or before this token
				    after a # operator.  */
#define NO_EXPAND	(1 << 10) /* Do not macro-expand this token.  */
#define PRAGMA_OP	(1 << 11) /* _Pragma token.  */
#define BOL		(1 << 12) /* Token at beginning of line.  */

/* Specify which field, if any, of the cpp_token union is used.  */

enum cpp_token_fld_kind {
  CPP_TOKEN_FLD_NODE,
  CPP_TOKEN_FLD_SOURCE,
  CPP_TOKEN_FLD_STR,
  CPP_TOKEN_FLD_ARG_NO,
  CPP_TOKEN_FLD_TOKEN_NO,
  CPP_TOKEN_FLD_PRAGMA,
  CPP_TOKEN_FLD_NONE
};

/* A macro argument in the cpp_token union.  */
struct GTY(()) cpp_macro_arg {
  /* Argument number.  */
  unsigned int arg_no;
  /* The original spelling of the macro argument token.  */
  cpp_hashnode *
    GTY ((nested_ptr (union tree_node,
		"%h ? CPP_HASHNODE (GCC_IDENT_TO_HT_IDENT (%h)) : NULL",
			"%h ? HT_IDENT_TO_GCC_IDENT (HT_NODE (%h)) : NULL")))
       spelling;
};

/* An identifier in the cpp_token union.  */
struct GTY(()) cpp_identifier {
  /* The canonical (UTF-8) spelling of the identifier.  */
  cpp_hashnode *
    GTY ((nested_ptr (union tree_node,
		"%h ? CPP_HASHNODE (GCC_IDENT_TO_HT_IDENT (%h)) : NULL",
			"%h ? HT_IDENT_TO_GCC_IDENT (HT_NODE (%h)) : NULL")))
       node;
  /* The original spelling of the identifier.  */
  cpp_hashnode *
    GTY ((nested_ptr (union tree_node,
		"%h ? CPP_HASHNODE (GCC_IDENT_TO_HT_IDENT (%h)) : NULL",
			"%h ? HT_IDENT_TO_GCC_IDENT (HT_NODE (%h)) : NULL")))
       spelling;
};

/* A preprocessing token.  This has been carefully packed and should
   occupy 16 bytes on 32-bit hosts and 24 bytes on 64-bit hosts.  */
struct GTY(()) cpp_token {

  /* Location of first char of token, together with range of full token.  */
  location_t src_loc;

  ENUM_BITFIELD(cpp_ttype) type : CHAR_BIT;  /* token type */
  unsigned short flags;		/* flags - see above */

  union cpp_token_u
  {
    /* An identifier.  */
    struct cpp_identifier GTY ((tag ("CPP_TOKEN_FLD_NODE"))) node;

    /* Inherit padding from this token.  */
    cpp_token * GTY ((tag ("CPP_TOKEN_FLD_SOURCE"))) source;

    /* A string, or number.  */
    struct cpp_string GTY ((tag ("CPP_TOKEN_FLD_STR"))) str;

    /* Argument no. (and original spelling) for a CPP_MACRO_ARG.  */
    struct cpp_macro_arg GTY ((tag ("CPP_TOKEN_FLD_ARG_NO"))) macro_arg;

    /* Original token no. for a CPP_PASTE (from a sequence of
       consecutive paste tokens in a macro expansion).  */
    unsigned int GTY ((tag ("CPP_TOKEN_FLD_TOKEN_NO"))) token_no;

    /* Caller-supplied identifier for a CPP_PRAGMA.  */
    unsigned int GTY ((tag ("CPP_TOKEN_FLD_PRAGMA"))) pragma;
  } GTY ((desc ("cpp_token_val_index (&%1)"))) val;
};

/* Say which field is in use.  */
extern enum cpp_token_fld_kind cpp_token_val_index (const cpp_token *tok);

/* A type wide enough to hold any multibyte source character.
   cpplib's character constant interpreter requires an unsigned type.
   Also, a typedef for the signed equivalent.
   The width of this type is capped at 32 bits; there do exist targets
   where wchar_t is 64 bits, but only in a non-default mode, and there
   would be no meaningful interpretation for a wchar_t value greater
   than 2^32 anyway -- the widest wide-character encoding around is
   ISO 10646, which stops at 2^31.  */
#if CHAR_BIT * SIZEOF_INT >= 32
# define CPPCHAR_SIGNED_T int
#elif CHAR_BIT * SIZEOF_LONG >= 32
# define CPPCHAR_SIGNED_T long
#else
# error "Cannot find a least-32-bit signed integer type"
#endif
typedef unsigned CPPCHAR_SIGNED_T cppchar_t;
typedef CPPCHAR_SIGNED_T cppchar_signed_t;

/* Style of header dependencies to generate.  */
enum cpp_deps_style { DEPS_NONE = 0, DEPS_USER, DEPS_SYSTEM };

/* Structured format of module dependencies to generate.  */
enum cpp_fdeps_format { FDEPS_FMT_NONE = 0, FDEPS_FMT_P1689R5 };

/* The possible normalization levels, from most restrictive to least.  */
enum cpp_normalize_level {
  /* In NFKC.  */
  normalized_KC = 0,
  /* In NFC.  */
  normalized_C,
  /* In NFC, except for subsequences where being in NFC would make
     the identifier invalid.  */
  normalized_identifier_C,
  /* Not normalized at all.  */
  normalized_none
};

enum cpp_main_search
{
  CMS_none,    /* A regular source file.  */
  CMS_header,  /* Is a directly-specified header file (eg PCH or
		  header-unit).  */
  CMS_user,    /* Search the user INCLUDE path.  */
  CMS_system,  /* Search the system INCLUDE path.  */
};

/* The possible bidirectional control characters checking levels.  */
enum cpp_bidirectional_level {
  /* No checking.  */
  bidirectional_none = 0,
  /* Only detect unpaired uses of bidirectional control characters.  */
  bidirectional_unpaired = 1,
  /* Detect any use of bidirectional control characters.  */
  bidirectional_any = 2,
  /* Also warn about UCNs.  */
  bidirectional_ucn = 4
};

/* This structure is nested inside struct cpp_reader, and
   carries all the options visible to the command line.  */
struct cpp_options
{
  /* The language we're preprocessing.  */
  enum c_lang lang;

  /* Nonzero means use extra default include directories for C++.  */
  unsigned char cplusplus;

  /* Nonzero means handle cplusplus style comments.  */
  unsigned char cplusplus_comments;

  /* Nonzero means define __OBJC__, treat @ as a special token, use
     the OBJC[PLUS]_INCLUDE_PATH environment variable, and allow
     "#import".  */
  unsigned char objc;

  /* Nonzero means don't copy comments into the output file.  */
  unsigned char discard_comments;

  /* Nonzero means don't copy comments into the output file during
     macro expansion.  */
  unsigned char discard_comments_in_macro_exp;

  /* Nonzero means process the ISO trigraph sequences.  */
  unsigned char trigraphs;

  /* Nonzero means process the ISO digraph sequences.  */
  unsigned char digraphs;

  /* Nonzero means to allow hexadecimal floats and LL suffixes.  */
  unsigned char extended_numbers;

  /* Nonzero means process u/U prefix literals (UTF-16/32).  */
  unsigned char uliterals;

  /* Nonzero means process u8 prefixed character literals (UTF-8).  */
  unsigned char utf8_char_literals;

  /* Nonzero means process r/R raw strings.  If this is set, uliterals
     must be set as well.  */
  unsigned char rliterals;

  /* Nonzero means print names of header files (-H).  */
  unsigned char print_include_names;

  /* Nonzero means complain about deprecated features.  */
  unsigned char cpp_warn_deprecated;

  /* Nonzero means warn if slash-star appears in a comment.  */
  unsigned char warn_comments;

  /* Nonzero means to warn about __DATA__, __TIME__ and __TIMESTAMP__ usage.   */
  unsigned char warn_date_time;

  /* Nonzero means warn if a user-supplied include directory does not
     exist.  */
  unsigned char warn_missing_include_dirs;

  /* Nonzero means warn if there are any trigraphs.  */
  unsigned char warn_trigraphs;

  /* Nonzero means warn about multicharacter charconsts.  */
  unsigned char warn_multichar;

  /* Nonzero means warn about various incompatibilities with
     traditional C.  */
  unsigned char cpp_warn_traditional;

  /* Nonzero means warn about long long numeric constants.  */
  unsigned char cpp_warn_long_long;

  /* Nonzero means warn about text after an #endif (or #else).  */
  unsigned char warn_endif_labels;

  /* Nonzero means warn about implicit sign changes owing to integer
     promotions.  */
  unsigned char warn_num_sign_change;

  /* Zero means don't warn about __VA_ARGS__ usage in c89 pedantic mode.
     Presumably the usage is protected by the appropriate #ifdef.  */
  unsigned char warn_variadic_macros;

  /* Nonzero means warn about builtin macros that are redefined or
     explicitly undefined.  */
  unsigned char warn_builtin_macro_redefined;

  /* Different -Wimplicit-fallthrough= levels.  */
  unsigned char cpp_warn_implicit_fallthrough;

  /* Nonzero means warn about a define of a different macro right after
     #ifndef/#if !defined header guard directive.  */
  unsigned char warn_header_guard;

  /* Nonzero means we should look for header.gcc files that remap file
     names.  */
  unsigned char remap;

  /* Zero means dollar signs are punctuation.  */
  unsigned char dollars_in_ident;

  /* Nonzero means UCNs are accepted in identifiers.  */
  unsigned char extended_identifiers;

  /* True if we should warn about dollars in identifiers or numbers
     for this translation unit.  */
  unsigned char warn_dollars;

  /* Nonzero means warn if undefined identifiers are evaluated in an #if.  */
  unsigned char warn_undef;

  /* Nonzero means warn if "defined" is encountered in a place other than
     an #if.  */
  unsigned char warn_expansion_to_defined;

  /* Nonzero means warn of unused macros from the main file.  */
  unsigned char warn_unused_macros;

  /* Nonzero for the 1999 C Standard, including corrigenda and amendments.  */
  unsigned char c99;

  /* Nonzero if we are conforming to a specific C or C++ standard.  */
  unsigned char std;

  /* Nonzero means give all the error messages the ANSI standard requires.  */
  unsigned char cpp_pedantic;

  /* Nonzero means we're looking at already preprocessed code, so don't
     bother trying to do macro expansion and whatnot.  */
  unsigned char preprocessed;

  /* Nonzero means we are going to emit debugging logs during
     preprocessing.  */
  unsigned char debug;

  /* Nonzero means we are tracking locations of tokens involved in
     macro expansion. 1 Means we track the location in degraded mode
     where we do not track locations of tokens resulting from the
     expansion of arguments of function-like macro.  2 Means we do
     track all macro expansions. This last option is the one that
     consumes the highest amount of memory.  */
  unsigned char track_macro_expansion;

  /* Nonzero means handle C++ alternate operator names.  */
  unsigned char operator_names;

  /* Nonzero means warn about use of C++ alternate operator names.  */
  unsigned char warn_cxx_operator_names;

  /* True for traditional preprocessing.  */
  unsigned char traditional;

  /* Nonzero for C++ 2011 Standard user-defined literals.  */
  unsigned char user_literals;

  /* Nonzero means warn when a string or character literal is followed by a
     ud-suffix which does not beging with an underscore.  */
  unsigned char warn_literal_suffix;

  /* Nonzero means interpret imaginary, fixed-point, or other gnu extension
     literal number suffixes as user-defined literal number suffixes.  */
  unsigned char ext_numeric_literals;

  /* Nonzero means extended identifiers allow the characters specified
     in C11.  */
  unsigned char c11_identifiers;

  /* Nonzero means extended identifiers allow the characters specified
     by Unicode XID_Start and XID_Continue properties.  */
  unsigned char xid_identifiers;

  /* Nonzero for C++ 2014 Standard binary constants.  */
  unsigned char binary_constants;

  /* Nonzero for C2Y imaginary (floating) constants.  */
  unsigned char imaginary_constants;

  /* Nonzero for C++ 2014 Standard digit separators.  */
  unsigned char digit_separators;

  /* Nonzero for C23 decimal floating-point constants.  */
  unsigned char dfp_constants;

  /* Nonzero for C++20 __VA_OPT__ feature.  */
  unsigned char va_opt;

  /* Nonzero for the '::' token.  */
  unsigned char scope;

  /* Nonzero for the '#elifdef' and '#elifndef' directives.  */
  unsigned char elifdef;

  /* Nonzero for the '#warning' directive.  */
  unsigned char warning_directive;

  /* Nonzero means tokenize C++20 module directives.  */
  unsigned char module_directives;

  /* Nonzero for C++23 size_t literals.  */
  unsigned char size_t_literals;

  /* Nonzero for C++23 delimited escape sequences.  */
  unsigned char delimited_escape_seqs;

  /* Nonzero for C++23 named universal character escape sequences.  */
  unsigned char named_uc_escape_seqs;

  /* Nonzero for C2Y 0o prefixed octal integer constants.  */
  unsigned char octal_constants;

  /* Nonzero for 'true' and 'false' in #if expressions.  */
  unsigned char true_false;

  /* Nonzero for the '#embed' directive.  */
  unsigned char embed;

  /* Holds the name of the target (execution) character set.  */
  const char *narrow_charset;

  /* Holds the name of the target wide character set.  */
  const char *wide_charset;

  /* Holds the name of the input character set.  */
  const char *input_charset;

  /* The minimum permitted level of normalization before a warning
     is generated.  See enum cpp_normalize_level.  */
  int warn_normalize;

  /* True to warn about precompiled header files we couldn't use.  */
  bool warn_invalid_pch;

  /* True if dependencies should be restored from a precompiled header.  */
  bool restore_pch_deps;

  /* True if warn about differences between C90 and C99.  */
  signed char cpp_warn_c90_c99_compat;

  /* True if warn about differences between C11 and C23.  */
  signed char cpp_warn_c11_c23_compat;

  /* True if warn about differences between C23 and C2Y.  */
  signed char cpp_warn_c23_c2y_compat;

  /* True if warn about differences between C++98 and C++11.  */
  bool cpp_warn_cxx11_compat;

  /* True if warn about differences between C++17 and C++20.  */
  bool cpp_warn_cxx20_compat;

  /* Nonzero if bidirectional control characters checking is on.  See enum
     cpp_bidirectional_level.  */
  unsigned char cpp_warn_bidirectional;

  /* True if libcpp should warn about invalid UTF-8 characters in comments.
     2 if it should be a pedwarn.  */
  unsigned char cpp_warn_invalid_utf8;

  /* True if libcpp should warn about invalid forms of delimited or named
     escape sequences.  */
  bool cpp_warn_unicode;

  /* True if -finput-charset= option has been used explicitly.  */
  bool cpp_input_charset_explicit;

  /* -Wleading-whitespace= value.  */
  unsigned char cpp_warn_leading_whitespace;

  /* -Wtrailing-whitespace= value.  */
  unsigned char cpp_warn_trailing_whitespace;

  /* -ftabstop= value.  */
  unsigned int cpp_tabstop;

  /* Dependency generation.  */
  struct
  {
    /* Style of header dependencies to generate.  */
    enum cpp_deps_style style;

    /* Structured format of module dependencies to generate.  */
    enum cpp_fdeps_format fdeps_format;

    /* Assume missing files are generated files.  */
    bool missing_files;

    /* Generate phony targets for each dependency apart from the first
       one.  */
    bool phony_targets;

    /* Generate dependency info for modules.  */
    bool modules;

    /* If true, no dependency is generated on the main file.  */
    bool ignore_main_file;

    /* If true, intend to use the preprocessor output (e.g., for compilation)
       in addition to the dependency info.  */
    bool need_preprocessor_output;
  } deps;

  /* Target-specific features set by the front end or client.  */

  /* Precision for target CPP arithmetic, target characters, target
     ints and target wide characters, respectively.  */
  size_t precision, char_precision, int_precision, wchar_precision;

  /* True means chars (wide chars, UTF-8 chars) are unsigned.  */
  bool unsigned_char, unsigned_wchar, unsigned_utf8char;

  /* True if the most significant byte in a word has the lowest
     address in memory.  */
  bool bytes_big_endian;

  /* Nonzero means __STDC__ should have the value 0 in system headers.  */
  unsigned char stdc_0_in_system_headers;

  /* True disables tokenization outside of preprocessing directives. */
  bool directives_only;

  /* True enables canonicalization of system header file paths. */
  bool canonical_system_headers;

  /* The maximum depth of the nested #include.  */
  unsigned int max_include_depth;

  cpp_main_search main_search : 8;
};

#if GCC_VERSION >= 3005
#define ATTRIBUTE_CPP_PPDIAG(m, n) \
  __attribute__ ((__format__ (__gcc_diag__, m , n))) ATTRIBUTE_NONNULL(m)
#else
#define ATTRIBUTE_CPP_PPDIAG(m, n) ATTRIBUTE_NONNULL(m)
#endif

/* Diagnostic levels.  To get a diagnostic without associating a
   position in the translation unit with it, use cpp_error_with_line
   with a line number of zero.  */

enum cpp_diagnostic_level {
  /* Warning, an error with -Werror.  */
  CPP_DL_WARNING = 0,
  /* Same as CPP_DL_WARNING, except it is not suppressed in system headers.  */
  CPP_DL_WARNING_SYSHDR,
  /* Warning, an error with -pedantic-errors or -Werror.  */
  CPP_DL_PEDWARN,
  /* An error.  */
  CPP_DL_ERROR,
  /* An internal consistency check failed.  Prints "internal error: ",
     otherwise the same as CPP_DL_ERROR.  */
  CPP_DL_ICE,
  /* An informative note following a warning.  */
  CPP_DL_NOTE,
  /* A fatal error.  */
  CPP_DL_FATAL
};

/* Warning reason codes. Use a reason code of CPP_W_NONE for unclassified
   warnings and diagnostics that are not warnings.  */

enum cpp_warning_reason {
  CPP_W_NONE = 0,
  CPP_W_DEPRECATED,
  CPP_W_COMMENTS,
  CPP_W_MISSING_INCLUDE_DIRS,
  CPP_W_TRIGRAPHS,
  CPP_W_MULTICHAR,
  CPP_W_TRADITIONAL,
  CPP_W_LONG_LONG,
  CPP_W_ENDIF_LABELS,
  CPP_W_NUM_SIGN_CHANGE,
  CPP_W_VARIADIC_MACROS,
  CPP_W_BUILTIN_MACRO_REDEFINED,
  CPP_W_DOLLARS,
  CPP_W_UNDEF,
  CPP_W_UNUSED_MACROS,
  CPP_W_CXX_OPERATOR_NAMES,
  CPP_W_NORMALIZE,
  CPP_W_INVALID_PCH,
  CPP_W_WARNING_DIRECTIVE,
  CPP_W_LITERAL_SUFFIX,
  CPP_W_SIZE_T_LITERALS,
  CPP_W_DATE_TIME,
  CPP_W_PEDANTIC,
  CPP_W_C90_C99_COMPAT,
  CPP_W_C11_C23_COMPAT,
  CPP_W_C23_C2Y_COMPAT,
  CPP_W_CXX11_COMPAT,
  CPP_W_CXX20_COMPAT,
  CPP_W_CXX14_EXTENSIONS,
  CPP_W_CXX17_EXTENSIONS,
  CPP_W_CXX20_EXTENSIONS,
  CPP_W_CXX23_EXTENSIONS,
  CPP_W_EXPANSION_TO_DEFINED,
  CPP_W_BIDIRECTIONAL,
  CPP_W_INVALID_UTF8,
  CPP_W_UNICODE,
  CPP_W_HEADER_GUARD,
  CPP_W_PRAGMA_ONCE_OUTSIDE_HEADER,
  CPP_W_LEADING_WHITESPACE,
  CPP_W_TRAILING_WHITESPACE
};

/* Callback for header lookup for HEADER, which is the name of a
   source file.  It is used as a method of last resort to find headers
   that are not otherwise found during the normal include processing.
   The return value is the malloced name of a header to try and open,
   if any, or NULL otherwise.  This callback is called only if the
   header is otherwise unfound.  */
typedef const char *(*missing_header_cb)(cpp_reader *, const char *header, cpp_dir **);

/* Call backs to cpplib client.  */
struct cpp_callbacks
{
  /* Called when a new line of preprocessed output is started.  */
  void (*line_change) (cpp_reader *, const cpp_token *, int);

  /* Called when switching to/from a new file.
     The line_map is for the new file.  It is NULL if there is no new file.
     (In C this happens when done with <built-in>+<command line> and also
     when done with a main file.)  This can be used for resource cleanup.  */
  void (*file_change) (cpp_reader *, const line_map_ordinary *);

  void (*dir_change) (cpp_reader *, const char *);
  void (*include) (cpp_reader *, location_t, const unsigned char *,
		   const char *, int, const cpp_token **);
  void (*define) (cpp_reader *, location_t, cpp_hashnode *);
  void (*undef) (cpp_reader *, location_t, cpp_hashnode *);
  void (*ident) (cpp_reader *, location_t, const cpp_string *);
  void (*def_pragma) (cpp_reader *, location_t);
  int (*valid_pch) (cpp_reader *, const char *, int);
  void (*read_pch) (cpp_reader *, const char *, int, const char *);
  missing_header_cb missing_header;

  /* Context-sensitive macro support.  Returns macro (if any) that should
     be expanded.  */
  cpp_hashnode * (*macro_to_expand) (cpp_reader *, const cpp_token *);

  /* Called to emit a diagnostic.  This callback receives the
     translated message.  */
  bool (*diagnostic) (cpp_reader *,
		      enum cpp_diagnostic_level,
		      enum cpp_warning_reason,
		      rich_location *,
		      const char *, va_list *)
       ATTRIBUTE_CPP_PPDIAG (5,0);

  /* Callbacks for when a macro is expanded, or tested (whether
     defined or not at the time) in #ifdef, #ifndef or "defined".  */
  void (*used_define) (cpp_reader *, location_t, cpp_hashnode *);
  void (*used_undef) (cpp_reader *, location_t, cpp_hashnode *);
  /* Called before #define and #undef or other macro definition
     changes are processed.  */
  void (*before_define) (cpp_reader *);
  /* Called whenever a macro is expanded or tested.
     Second argument is the location of the start of the current expansion.  */
  void (*used) (cpp_reader *, location_t, cpp_hashnode *);

  /* Callback to identify whether an attribute exists.  */
  int (*has_attribute) (cpp_reader *, bool);

  /* Callback to determine whether a built-in function is recognized.  */
  int (*has_builtin) (cpp_reader *);

  /* Callback to determine whether a feature is available.  */
  int (*has_feature) (cpp_reader *, bool);

  /* Callback that can change a user lazy into normal macro.  */
  void (*user_lazy_macro) (cpp_reader *, cpp_macro *, unsigned);

  /* Callback to handle deferred cpp_macros.  */
  cpp_macro *(*user_deferred_macro) (cpp_reader *, location_t, cpp_hashnode *);

  /* Callback to parse SOURCE_DATE_EPOCH from environment.  */
  time_t (*get_source_date_epoch) (cpp_reader *);

  /* Callback for providing suggestions for misspelled directives.  */
  const char *(*get_suggestion) (cpp_reader *, const char *, const char *const *);

  /* Callback for when a comment is encountered, giving the location
     of the opening slash, a pointer to the content (which is not
     necessarily 0-terminated), and the length of the content.
     The content contains the opening slash-star (or slash-slash),
     and for C-style comments contains the closing star-slash.  For
     C++-style comments it does not include the terminating newline.  */
  void (*comment) (cpp_reader *, location_t, const unsigned char *,
		   size_t);

  /* Callback for filename remapping in __FILE__ and __BASE_FILE__ macro
     expansions.  */
  const char *(*remap_filename) (const char*);

  /* Maybe translate a #include into something else.  Return a
     cpp_buffer containing the translation if translating.  */
  char *(*translate_include) (cpp_reader *, line_maps *, location_t,
			      const char *path);
};

#ifdef VMS
#define INO_T_CPP ino_t ino[3]
#elif defined (_AIX) && SIZEOF_INO_T == 4
#define INO_T_CPP ino64_t ino
#else
#define INO_T_CPP ino_t ino
#endif

#if defined (_AIX) && SIZEOF_DEV_T == 4
#define DEV_T_CPP dev64_t dev
#else
#define DEV_T_CPP dev_t dev
#endif

/* Chain of directories to look for include files in.  */
struct cpp_dir
{
  /* NULL-terminated singly-linked list.  */
  struct cpp_dir *next;

  /* NAME of the directory, NUL-terminated.  */
  char *name;
  unsigned int len;

  /* One if a system header, two if a system header that has extern
     "C" guards for C++.  */
  unsigned char sysp;

  /* Is this a user-supplied directory? */
  bool user_supplied_p;

  /* The canonicalized NAME as determined by lrealpath.  This field
     is only used by hosts that lack reliable inode numbers.  */
  char *canonical_name;

  /* Mapping of file names for this directory for MS-DOS and related
     platforms.  A NULL-terminated array of (from, to) pairs.  */
  const char **name_map;

  /* Routine to construct pathname, given the search path name and the
     HEADER we are trying to find, return a constructed pathname to
     try and open.  If this is NULL, the constructed pathname is as
     constructed by append_file_to_dir.  */
  char *(*construct) (const char *header, cpp_dir *dir);

  /* The C front end uses these to recognize duplicated
     directories in the search path.  */
  INO_T_CPP;
  DEV_T_CPP;
};

/* The kind of the cpp_macro.  */
enum cpp_macro_kind {
  cmk_macro,	/* An ISO macro (token expansion).  */
  cmk_assert,   /* An assertion.  */
  cmk_traditional	/* A traditional macro (text expansion).  */
};

/* Each macro definition is recorded in a cpp_macro structure.
   Variadic macros cannot occur with traditional cpp.  */
struct GTY(()) cpp_macro {
  union cpp_parm_u
  {
    /* Parameters, if any.  If parameter names use extended identifiers,
       the original spelling of those identifiers, not the canonical
       UTF-8 spelling, goes here.  */
    cpp_hashnode ** GTY ((tag ("false"),
			  nested_ptr (union tree_node,
	"%h ? CPP_HASHNODE (GCC_IDENT_TO_HT_IDENT (%h)) : NULL",
	"%h ? HT_IDENT_TO_GCC_IDENT (HT_NODE (%h)) : NULL"),
			  length ("%1.paramc"))) params;

    /* If this is an assertion, the next one in the chain.  */
    cpp_macro *GTY ((tag ("true"))) next;
  } GTY ((desc ("%1.kind == cmk_assert"))) parm;

  /* Definition line number.  */
  location_t line;

  /* Number of tokens in body, or bytes for traditional macros.  */
  /* Do we really need 2^32-1 range here?  */
  unsigned int count;

  /* Number of parameters.  */
  unsigned short paramc;

  /* Non-zero if this is a user-lazy macro, value provided by user.  */
  unsigned char lazy;

  /* The kind of this macro (ISO, trad or assert) */
  unsigned kind : 2;

  /* If a function-like macro.  */
  unsigned int fun_like : 1;

  /* If a variadic macro.  */
  unsigned int variadic : 1;

  /* If macro defined in system header.  */
  unsigned int syshdr   : 1;

  /* Nonzero if it has been expanded or had its existence tested.  */
  unsigned int used     : 1;

  /* Indicate whether the tokens include extra CPP_PASTE tokens at the
     end to track invalid redefinitions with consecutive CPP_PASTE
     tokens.  */
  unsigned int extra_tokens : 1;

  /* Imported C++20 macro (from a header unit).  */
  unsigned int imported_p : 1;

  /* 0 bits spare (32-bit). 32 on 64-bit target.  */

  union cpp_exp_u
  {
    /* Trailing array of replacement tokens (ISO), or assertion body value.  */
    cpp_token GTY ((tag ("false"), length ("%1.count"))) tokens[1];

    /* Pointer to replacement text (traditional).  See comment at top
       of cpptrad.c for how traditional function-like macros are
       encoded.  */
    const unsigned char *GTY ((tag ("true"))) text;
  } GTY ((desc ("%1.kind == cmk_traditional"))) exp;
};

/* Poisoned identifiers are flagged NODE_POISONED.  NODE_OPERATOR (C++
   only) indicates an identifier that behaves like an operator such as
   "xor".  NODE_DIAGNOSTIC is for speed in lex_token: it indicates a
   diagnostic may be required for this node.  Currently this only
   applies to __VA_ARGS__, poisoned identifiers, and -Wc++-compat
   warnings about NODE_OPERATOR.  */

/* Hash node flags.  */
#define NODE_OPERATOR	(1 << 0)	/* C++ named operator.  */
#define NODE_POISONED	(1 << 1)	/* Poisoned identifier.  */
#define NODE_DIAGNOSTIC (1 << 2)	/* Possible diagnostic when lexed.  */
#define NODE_WARN	(1 << 3)	/* Warn if redefined or undefined.  */
#define NODE_DISABLED	(1 << 4)	/* A disabled macro.  */
#define NODE_USED	(1 << 5)	/* Dumped with -dU.  */
#define NODE_CONDITIONAL (1 << 6)	/* Conditional macro */
#define NODE_WARN_OPERATOR (1 << 7)	/* Warn about C++ named operator.  */
#define NODE_MODULE (1 << 8)		/* C++-20 module-related name.  */

/* Different flavors of hash node.  */
enum node_type
{
  NT_VOID = 0,	   /* Maybe an assert?  */
  NT_MACRO_ARG,	   /* A macro arg.  */
  NT_USER_MACRO,   /* A user macro.  */
  NT_BUILTIN_MACRO, /* A builtin macro.  */
  NT_MACRO_MASK = NT_USER_MACRO  /* Mask for either macro kind.  */
};

/* Different flavors of builtin macro.  _Pragma is an operator, but we
   handle it with the builtin code for efficiency reasons.  */
enum cpp_builtin_type
{
  BT_SPECLINE = 0,		/* `__LINE__' */
  BT_DATE,			/* `__DATE__' */
  BT_FILE,			/* `__FILE__' */
  BT_FILE_NAME,			/* `__FILE_NAME__' */
  BT_BASE_FILE,			/* `__BASE_FILE__' */
  BT_INCLUDE_LEVEL,		/* `__INCLUDE_LEVEL__' */
  BT_TIME,			/* `__TIME__' */
  BT_STDC,			/* `__STDC__' */
  BT_PRAGMA,			/* `_Pragma' operator */
  BT_TIMESTAMP,			/* `__TIMESTAMP__' */
  BT_COUNTER,			/* `__COUNTER__' */
  BT_HAS_ATTRIBUTE,		/* `__has_attribute(x)' */
  BT_HAS_STD_ATTRIBUTE,		/* `__has_c_attribute(x)' */
  BT_HAS_BUILTIN,		/* `__has_builtin(x)' */
  BT_HAS_INCLUDE,		/* `__has_include(x)' */
  BT_HAS_INCLUDE_NEXT,		/* `__has_include_next(x)' */
  BT_HAS_EMBED,			/* `__has_embed(x)' */
  BT_HAS_FEATURE,		/* `__has_feature(x)' */
  BT_HAS_EXTENSION		/* `__has_extension(x)' */
};

#define CPP_HASHNODE(HNODE)	((cpp_hashnode *) (HNODE))
#define HT_NODE(NODE)		(&(NODE)->ident)
#define NODE_LEN(NODE)		HT_LEN (HT_NODE (NODE))
#define NODE_NAME(NODE)		HT_STR (HT_NODE (NODE))

/* The common part of an identifier node shared amongst all 3 C front
   ends.  Also used to store CPP identifiers, which are a superset of
   identifiers in the grammatical sense.  */

union GTY(()) _cpp_hashnode_value {
  /* Assert (maybe NULL) */
  cpp_macro * GTY((tag ("NT_VOID"))) answers;
  /* Macro (maybe NULL) */
  cpp_macro * GTY((tag ("NT_USER_MACRO"))) macro;
  /* Code for a builtin macro.  */
  enum cpp_builtin_type GTY ((tag ("NT_BUILTIN_MACRO"))) builtin;
  /* Macro argument index.  */
  unsigned short GTY ((tag ("NT_MACRO_ARG"))) arg_index;
};

struct GTY(()) cpp_hashnode {
  struct ht_identifier ident;
  unsigned int is_directive : 1;
  unsigned int directive_index : 7;	/* If is_directive,
					   then index into directive table.
					   Otherwise, a NODE_OPERATOR.  */
  unsigned int rid_code : 8;		/* Rid code - for front ends.  */
  unsigned int flags : 9;		/* CPP flags.  */
  ENUM_BITFIELD(node_type) type : 2;	/* CPP node type.  */

  /* 5 bits spare.  */

  /* The deferred cookie is applicable to NT_USER_MACRO or NT_VOID.
     The latter for when a macro had a prevailing undef.
     On a 64-bit system there would be 32-bits of padding to the value
     field.  So placing the deferred index here is not costly.   */
  unsigned deferred;			/* Deferred cookie  */

  union _cpp_hashnode_value GTY ((desc ("%1.type"))) value;
};

/* Extra information we may need to store per identifier, which is needed rarely
   enough that it's not worth adding directly into the main identifier hash.  */
struct GTY(()) cpp_hashnode_extra
{
  struct ht_identifier ident;
  location_t poisoned_loc;
};

/* A class for iterating through the source locations within a
   string token (before escapes are interpreted, and before
   concatenation).  */

class cpp_string_location_reader {
 public:
  cpp_string_location_reader (location_t src_loc,
			      line_maps *line_table);

  source_range get_next ();

 private:
  location_t m_loc;
  int m_offset_per_column;
};

/* A class for storing the source ranges of all of the characters within
   a string literal, after escapes are interpreted, and after
   concatenation.

   This is not GTY-marked, as instances are intended to be temporary.  */

class cpp_substring_ranges
{
 public:
  cpp_substring_ranges ();
  ~cpp_substring_ranges ();

  int get_num_ranges () const { return m_num_ranges; }
  source_range get_range (int idx) const
  {
    linemap_assert (idx < m_num_ranges);
    return m_ranges[idx];
  }

  void add_range (source_range range);
  void add_n_ranges (int num, cpp_string_location_reader &loc_reader);

 private:
  source_range *m_ranges;
  int m_num_ranges;
  int m_alloc_ranges;
};

/* Call this first to get a handle to pass to other functions.

   The first hash table argument is for associating a struct cpp_hashnode
   with each identifier.  The second hash table argument is for associating
   a struct cpp_hashnode_extra with each identifier that needs one.  For
   either, pass in a NULL pointer if you want cpplib to create and manage
   the hash table itself, or else pass a suitably initialized hash table to
   be managed external to libcpp, as is done by the C-family frontends.  */
extern cpp_reader *cpp_create_reader (enum c_lang, struct ht *,
				      class line_maps *,
				      struct ht * = nullptr);

/* Reset the cpp_reader's line_map.  This is only used after reading a
   PCH file.  */
extern void cpp_set_line_map (cpp_reader *, class line_maps *);

/* Call this to change the selected language standard (e.g. because of
   command line options).  */
extern void cpp_set_lang (cpp_reader *, enum c_lang);

/* Set the include paths.  */
extern void cpp_set_include_chains (cpp_reader *, cpp_dir *, cpp_dir *,
				    cpp_dir *, int);

/* Call these to get pointers to the options, callback, and deps
   structures for a given reader.  These pointers are good until you
   call cpp_finish on that reader.  You can either edit the callbacks
   through the pointer returned from cpp_get_callbacks, or set them
   with cpp_set_callbacks.  */
extern cpp_options *cpp_get_options (cpp_reader *) ATTRIBUTE_PURE;
extern cpp_callbacks *cpp_get_callbacks (cpp_reader *) ATTRIBUTE_PURE;
extern void cpp_set_callbacks (cpp_reader *, cpp_callbacks *);
extern class mkdeps *cpp_get_deps (cpp_reader *) ATTRIBUTE_PURE;

extern const char *cpp_probe_header_unit (cpp_reader *, const char *file,
					  bool angle_p,  location_t);

/* Call these to get name data about the various compile-time
   charsets.  */
extern const char *cpp_get_narrow_charset_name (cpp_reader *) ATTRIBUTE_PURE;
extern const char *cpp_get_wide_charset_name (cpp_reader *) ATTRIBUTE_PURE;

/* This function reads the file, but does not start preprocessing.  It
   returns the name of the original file; this is the same as the
   input file, except for preprocessed input.  This will generate at
   least one file change callback, and possibly a line change callback
   too.  If there was an error opening the file, it returns NULL.  */
extern const char *cpp_read_main_file (cpp_reader *, const char *,
				       bool injecting = false);
extern location_t cpp_main_loc (const cpp_reader *);

/* Adjust for the main file to be an include.  */
extern void cpp_retrofit_as_include (cpp_reader *);

/* Set up built-ins with special behavior.  Use cpp_init_builtins()
   instead unless your know what you are doing.  */
extern void cpp_init_special_builtins (cpp_reader *);

/* Set up built-ins like __FILE__.  */
extern void cpp_init_builtins (cpp_reader *, int);

/* This is called after options have been parsed, and partially
   processed.  */
extern void cpp_post_options (cpp_reader *);

/* Set up translation to the target character set.  */
extern void cpp_init_iconv (cpp_reader *);

/* Call this to finish preprocessing.  If you requested dependency
   generation, pass open stream(s) to write the information to,
   otherwise NULL.  It is your responsibility to close the stream(s).  */
extern void cpp_finish (cpp_reader *, FILE *deps_stream, FILE *fdeps_stream = NULL);

/* Call this to release the handle at the end of preprocessing.  Any
   use of the handle after this function returns is invalid.  */
extern void cpp_destroy (cpp_reader *);

extern unsigned int cpp_token_len (const cpp_token *);
extern unsigned char *cpp_token_as_text (cpp_reader *, const cpp_token *);
extern unsigned char *cpp_spell_token (cpp_reader *, const cpp_token *,
				       unsigned char *, bool);
extern void cpp_register_pragma (cpp_reader *, const char *, const char *,
				 void (*) (cpp_reader *), bool);
extern void cpp_register_deferred_pragma (cpp_reader *, const char *,
					  const char *, unsigned, bool, bool);
extern int cpp_avoid_paste (cpp_reader *, const cpp_token *,
			    const cpp_token *);
extern const cpp_token *cpp_get_token (cpp_reader *);
extern const cpp_token *cpp_get_token_with_location (cpp_reader *,
						     location_t *);
inline bool cpp_user_macro_p (const cpp_hashnode *node)
{
  return node->type == NT_USER_MACRO;
}
inline bool cpp_builtin_macro_p (const cpp_hashnode *node)
{
  return node->type == NT_BUILTIN_MACRO;
}
inline bool cpp_macro_p (const cpp_hashnode *node)
{
  return node->type & NT_MACRO_MASK;
}
inline cpp_macro *cpp_set_deferred_macro (cpp_hashnode *node,
					  cpp_macro *forced = NULL)
{
  cpp_macro *old = node->value.macro;

  node->value.macro = forced;
  node->type = NT_USER_MACRO;
  node->flags &= ~NODE_USED;

  return old;
}
cpp_macro *cpp_get_deferred_macro (cpp_reader *, cpp_hashnode *, location_t);

/* Returns true if NODE is a function-like user macro.  */
inline bool cpp_fun_like_macro_p (cpp_hashnode *node)
{
  return cpp_user_macro_p (node) && node->value.macro->fun_like;
}

extern const unsigned char *cpp_macro_definition (cpp_reader *, cpp_hashnode *);
extern const unsigned char *cpp_macro_definition (cpp_reader *, cpp_hashnode *,
						  const cpp_macro *);
inline location_t cpp_macro_definition_location (cpp_hashnode *node)
{
  const cpp_macro *macro = node->value.macro;
  return macro ? macro->line : 0;
}
/* Return an idempotent time stamp (possibly from SOURCE_DATE_EPOCH).  */
enum class CPP_time_kind
{
  FIXED = -1,	/* Fixed time via source epoch.  */
  DYNAMIC = -2,	/* Dynamic via time(2).  */
  UNKNOWN = -3	/* Wibbly wobbly, timey wimey.  */
};
extern CPP_time_kind cpp_get_date (cpp_reader *, time_t *);

extern void _cpp_backup_tokens (cpp_reader *, unsigned int);
extern const cpp_token *cpp_peek_token (cpp_reader *, int);

/* Evaluate a CPP_*CHAR* token.  */
extern cppchar_t cpp_interpret_charconst (cpp_reader *, const cpp_token *,
					  unsigned int *, int *);
/* Evaluate a vector of CPP_*STRING* tokens.  */
extern bool cpp_interpret_string (cpp_reader *,
				  const cpp_string *, size_t,
				  cpp_string *, enum cpp_ttype);
extern const char *cpp_interpret_string_ranges (cpp_reader *pfile,
						const cpp_string *from,
						cpp_string_location_reader *,
						size_t count,
						cpp_substring_ranges *out,
						enum cpp_ttype type);
extern bool cpp_interpret_string_notranslate (cpp_reader *,
					      const cpp_string *, size_t,
					      cpp_string *, enum cpp_ttype);

/* Convert a host character constant to the execution character set.  */
extern cppchar_t cpp_host_to_exec_charset (cpp_reader *, cppchar_t);

/* Used to register macros and assertions, perhaps from the command line.
   The text is the same as the command line argument.  */
extern void cpp_define (cpp_reader *, const char *);
extern void cpp_define_unused (cpp_reader *, const char *);
extern void cpp_define_formatted (cpp_reader *pfile,
				  const char *fmt, ...) ATTRIBUTE_PRINTF_2;
extern void cpp_define_formatted_unused (cpp_reader *pfile,
					 const char *fmt,
					 ...) ATTRIBUTE_PRINTF_2;
extern void cpp_assert (cpp_reader *, const char *);
extern void cpp_undef (cpp_reader *, const char *);
extern void cpp_unassert (cpp_reader *, const char *);

/* Mark a node as a lazily defined macro.  */
extern void cpp_define_lazily (cpp_reader *, cpp_hashnode *node, unsigned N);

/* Undefine all macros and assertions.  */
extern void cpp_undef_all (cpp_reader *);

extern cpp_buffer *cpp_push_buffer (cpp_reader *, const unsigned char *,
				    size_t, int);
extern int cpp_defined (cpp_reader *, const unsigned char *, int);

/* A preprocessing number.  Code assumes that any unused high bits of
   the double integer are set to zero.  */

/* This type has to be equal to unsigned HOST_WIDE_INT, see
   gcc/c-family/c-lex.cc.  */
typedef uint64_t cpp_num_part;
typedef struct cpp_num cpp_num;
struct cpp_num
{
  cpp_num_part high;
  cpp_num_part low;
  bool unsignedp;  /* True if value should be treated as unsigned.  */
  bool overflow;   /* True if the most recent calculation overflowed.  */
};

/* cpplib provides two interfaces for interpretation of preprocessing
   numbers.

   cpp_classify_number categorizes numeric constants according to
   their field (integer, floating point, or invalid), radix (decimal,
   octal, hexadecimal), and type suffixes.  */

#define CPP_N_CATEGORY  0x000F
#define CPP_N_INVALID	0x0000
#define CPP_N_INTEGER	0x0001
#define CPP_N_FLOATING	0x0002

#define CPP_N_WIDTH	0x00F0
#define CPP_N_SMALL	0x0010	/* int, float, short _Fract/Accum  */
#define CPP_N_MEDIUM	0x0020	/* long, double, long _Fract/_Accum.  */
#define CPP_N_LARGE	0x0040	/* long long, long double,
				   long long _Fract/Accum.  */

#define CPP_N_WIDTH_MD	0xF0000	/* machine defined.  */
#define CPP_N_MD_W	0x10000
#define CPP_N_MD_Q	0x20000

#define CPP_N_RADIX	0x0F00
#define CPP_N_DECIMAL	0x0100
#define CPP_N_HEX	0x0200
#define CPP_N_OCTAL	0x0400
#define CPP_N_BINARY	0x0800

#define CPP_N_UNSIGNED	0x1000	/* Properties.  */
#define CPP_N_IMAGINARY	0x2000
#define CPP_N_DFLOAT	0x4000
#define CPP_N_DEFAULT	0x8000

#define CPP_N_FRACT	0x100000 /* Fract types.  */
#define CPP_N_ACCUM	0x200000 /* Accum types.  */
#define CPP_N_FLOATN	0x400000 /* _FloatN types.  */
#define CPP_N_FLOATNX	0x800000 /* _FloatNx types.  */

#define CPP_N_USERDEF	0x1000000 /* C++11 user-defined literal.  */

#define CPP_N_SIZE_T	0x2000000 /* C++23 size_t literal.  */
#define CPP_N_BFLOAT16	0x4000000 /* std::bfloat16_t type.  */
#define CPP_N_BITINT	0x8000000 /* C23 _BitInt literal.  */

#define CPP_N_WIDTH_FLOATN_NX	0xF0000000 /* _FloatN / _FloatNx value
					      of N, divided by 16.  */
#define CPP_FLOATN_SHIFT	24
#define CPP_FLOATN_MAX	0xF0

/* Classify a CPP_NUMBER token.  The return value is a combination of
   the flags from the above sets.  */
extern unsigned cpp_classify_number (cpp_reader *, const cpp_token *,
				     const char **, location_t);

/* Return the classification flags for a float suffix.  */
extern unsigned int cpp_interpret_float_suffix (cpp_reader *, const char *,
						size_t);

/* Return the classification flags for an int suffix.  */
extern unsigned int cpp_interpret_int_suffix (cpp_reader *, const char *,
					      size_t);

/* Evaluate a token classified as category CPP_N_INTEGER.  */
extern cpp_num cpp_interpret_integer (cpp_reader *, const cpp_token *,
				      unsigned int);

/* Sign extend a number, with PRECISION significant bits and all
   others assumed clear, to fill out a cpp_num structure.  */
cpp_num cpp_num_sign_extend (cpp_num, size_t);

/* Output a diagnostic of some kind.  */
extern bool cpp_error (cpp_reader *, enum cpp_diagnostic_level,
		       const char *msgid, ...)
  ATTRIBUTE_CPP_PPDIAG (3, 4);
extern bool cpp_warning (cpp_reader *, enum cpp_warning_reason,
			 const char *msgid, ...)
  ATTRIBUTE_CPP_PPDIAG (3, 4);
extern bool cpp_pedwarning (cpp_reader *, enum cpp_warning_reason,
			    const char *msgid, ...)
  ATTRIBUTE_CPP_PPDIAG (3, 4);
extern bool cpp_warning_syshdr (cpp_reader *, enum cpp_warning_reason reason,
				const char *msgid, ...)
  ATTRIBUTE_CPP_PPDIAG (3, 4);

/* As their counterparts above, but use RICHLOC.  */
extern bool cpp_warning_at (cpp_reader *, enum cpp_warning_reason,
			    rich_location *richloc, const char *msgid, ...)
  ATTRIBUTE_CPP_PPDIAG (4, 5);
extern bool cpp_pedwarning_at (cpp_reader *, enum cpp_warning_reason,
			       rich_location *richloc, const char *msgid, ...)
  ATTRIBUTE_CPP_PPDIAG (4, 5);

/* Output a diagnostic with "MSGID: " preceding the
   error string of errno.  No location is printed.  */
extern bool cpp_errno (cpp_reader *, enum cpp_diagnostic_level,
		       const char *msgid);
/* Similarly, but with "FILENAME: " instead of "MSGID: ", where
   the filename is not localized.  */
extern bool cpp_errno_filename (cpp_reader *, enum cpp_diagnostic_level,
				const char *filename, location_t loc);

/* Same as cpp_error, except additionally specifies a position as a
   (translation unit) physical line and physical column.  If the line is
   zero, then no location is printed.  */
extern bool cpp_error_with_line (cpp_reader *, enum cpp_diagnostic_level,
				 location_t, unsigned,
				 const char *msgid, ...)
  ATTRIBUTE_CPP_PPDIAG (5, 6);
extern bool cpp_warning_with_line (cpp_reader *, enum cpp_warning_reason,
				   location_t, unsigned,
				   const char *msgid, ...)
  ATTRIBUTE_CPP_PPDIAG (5, 6);
extern bool cpp_pedwarning_with_line (cpp_reader *, enum cpp_warning_reason,
				      location_t, unsigned,
				      const char *msgid, ...)
  ATTRIBUTE_CPP_PPDIAG (5, 6);
extern bool cpp_warning_with_line_syshdr (cpp_reader *, enum cpp_warning_reason,
					  location_t, unsigned,
					  const char *msgid, ...)
  ATTRIBUTE_CPP_PPDIAG (5, 6);

extern bool cpp_error_at (cpp_reader * pfile, enum cpp_diagnostic_level,
			  location_t src_loc, const char *msgid, ...)
  ATTRIBUTE_CPP_PPDIAG (4, 5);

extern bool cpp_error_at (cpp_reader * pfile, enum cpp_diagnostic_level,
			  rich_location *richloc, const char *msgid, ...)
  ATTRIBUTE_CPP_PPDIAG (4, 5);

/* In lex.cc */
extern int cpp_ideq (const cpp_token *, const char *);
extern void cpp_output_line (cpp_reader *, FILE *);
extern unsigned char *cpp_output_line_to_string (cpp_reader *,
						 const unsigned char *);
extern const unsigned char *cpp_alloc_token_string
  (cpp_reader *, const unsigned char *, unsigned);
extern void cpp_output_token (const cpp_token *, FILE *);
extern const char *cpp_type2name (enum cpp_ttype, unsigned char flags);
/* Returns the value of an escape sequence, truncated to the correct
   target precision.  PSTR points to the input pointer, which is just
   after the backslash.  LIMIT is how much text we have.  WIDE is true
   if the escape sequence is part of a wide character constant or
   string literal.  Handles all relevant diagnostics.  */
extern cppchar_t cpp_parse_escape (cpp_reader *, const unsigned char ** pstr,
				   const unsigned char *limit, int wide);

/* Structure used to hold a comment block at a given location in the
   source code.  */

typedef struct
{
  /* Text of the comment including the terminators.  */
  char *comment;

  /* source location for the given comment.  */
  location_t sloc;
} cpp_comment;

/* Structure holding all comments for a given cpp_reader.  */

typedef struct
{
  /* table of comment entries.  */
  cpp_comment *entries;

  /* number of actual entries entered in the table.  */
  int count;

  /* number of entries allocated currently.  */
  int allocated;
} cpp_comment_table;

/* Returns the table of comments encountered by the preprocessor. This
   table is only populated when pfile->state.save_comments is true. */
extern cpp_comment_table *cpp_get_comments (cpp_reader *);

/* In hash.c */

/* Lookup an identifier in the hashtable.  Puts the identifier in the
   table if it is not already there.  */
extern cpp_hashnode *cpp_lookup (cpp_reader *, const unsigned char *,
				 unsigned int);

typedef int (*cpp_cb) (cpp_reader *, cpp_hashnode *, void *);
extern void cpp_forall_identifiers (cpp_reader *, cpp_cb, void *);

/* In macro.cc */
extern void cpp_scan_nooutput (cpp_reader *);
extern int  cpp_sys_macro_p (cpp_reader *);
extern unsigned char *cpp_quote_string (unsigned char *, const unsigned char *,
					unsigned int);
extern bool cpp_compare_macros (const cpp_macro *macro1,
				const cpp_macro *macro2);

/* In files.cc */
extern bool cpp_included (cpp_reader *, const char *);
extern bool cpp_included_before (cpp_reader *, const char *, location_t);
extern void cpp_make_system_header (cpp_reader *, int, int);
extern bool cpp_push_include (cpp_reader *, const char *);
extern bool cpp_push_default_include (cpp_reader *, const char *);
extern void cpp_change_file (cpp_reader *, enum lc_reason, const char *);
extern const char *cpp_get_path (struct _cpp_file *);
extern cpp_dir *cpp_get_dir (struct _cpp_file *);
extern cpp_buffer *cpp_get_buffer (cpp_reader *);
extern struct _cpp_file *cpp_get_file (cpp_buffer *);
extern cpp_buffer *cpp_get_prev (cpp_buffer *);
extern void cpp_clear_file_cache (cpp_reader *);

/* cpp_get_converted_source returns the contents of the given file, as it exists
   after cpplib has read it and converted it from the input charset to the
   source charset.  Return struct will be zero-filled if the data could not be
   read for any reason.  The data starts at the DATA pointer, but the TO_FREE
   pointer is what should be passed to free(), as there may be an offset.  */
struct cpp_converted_source
{
  char *to_free;
  char *data;
  size_t len;
};
cpp_converted_source cpp_get_converted_source (const char *fname,
					       const char *input_charset);

/* In pch.cc */
struct save_macro_data;
extern int cpp_save_state (cpp_reader *, FILE *);
extern int cpp_write_pch_deps (cpp_reader *, FILE *);
extern int cpp_write_pch_state (cpp_reader *, FILE *);
extern int cpp_valid_state (cpp_reader *, const char *, int);
extern void cpp_prepare_state (cpp_reader *, struct save_macro_data **);
extern int cpp_read_state (cpp_reader *, const char *, FILE *,
			   struct save_macro_data *);

/* In lex.cc */
extern void cpp_force_token_locations (cpp_reader *, location_t);
extern void cpp_stop_forcing_token_locations (cpp_reader *);
enum CPP_DO_task
{
  CPP_DO_print,
  CPP_DO_location,
  CPP_DO_token
};

extern void cpp_directive_only_process (cpp_reader *pfile,
					void *data,
					void (*cb) (cpp_reader *,
						    CPP_DO_task,
						    void *data, ...));

/* In expr.cc */
extern enum cpp_ttype cpp_userdef_string_remove_type
  (enum cpp_ttype type);
extern enum cpp_ttype cpp_userdef_string_add_type
  (enum cpp_ttype type);
extern enum cpp_ttype cpp_userdef_char_remove_type
  (enum cpp_ttype type);
extern enum cpp_ttype cpp_userdef_char_add_type
  (enum cpp_ttype type);
extern bool cpp_userdef_string_p
  (enum cpp_ttype type);
extern bool cpp_userdef_char_p
  (enum cpp_ttype type);
extern const char * cpp_get_userdef_suffix
  (const cpp_token *);

/* In charset.cc */

/* The result of attempting to decode a run of UTF-8 bytes.  */

struct cpp_decoded_char
{
  const char *m_start_byte;
  const char *m_next_byte;

  bool m_valid_ch;
  cppchar_t m_ch;
};

/* Information for mapping between code points and display columns.

   This is a tabstop value, along with a callback for getting the
   widths of characters.  Normally this callback is cpp_wcwidth, but we
   support other schemes for escaping non-ASCII unicode as a series of
   ASCII chars when printing the user's source code in diagnostic-show-locus.cc

   For example, consider:
   - the Unicode character U+03C0 "GREEK SMALL LETTER PI" (UTF-8: 0xCF 0x80)
   - the Unicode character U+1F642 "SLIGHTLY SMILING FACE"
     (UTF-8: 0xF0 0x9F 0x99 0x82)
   - the byte 0xBF (a stray trailing byte of a UTF-8 character)
   Normally U+03C0 would occupy one display column, U+1F642
   would occupy two display columns, and the stray byte would be
   printed verbatim as one display column.

   However when escaping them as unicode code points as "<U+03C0>"
   and "<U+1F642>" they occupy 8 and 9 display columns respectively,
   and when escaping them as bytes as "<CF><80>" and "<F0><9F><99><82>"
   they occupy 8 and 16 display columns respectively.  In both cases
   the stray byte is escaped to <BF> as 4 display columns.  */

struct cpp_char_column_policy
{
  cpp_char_column_policy (int tabstop,
			  int (*width_cb) (cppchar_t c))
  : m_tabstop (tabstop),
    m_undecoded_byte_width (1),
    m_width_cb (width_cb)
  {}

  int m_tabstop;
  /* Width in display columns of a stray byte that isn't decodable
     as UTF-8.  */
  int m_undecoded_byte_width;
  int (*m_width_cb) (cppchar_t c);
};

/* A class to manage the state while converting a UTF-8 sequence to cppchar_t
   and computing the display width one character at a time.  */
class cpp_display_width_computation {
 public:
  cpp_display_width_computation (const char *data, int data_length,
				 const cpp_char_column_policy &policy);
  const char *next_byte () const { return m_next; }
  int bytes_processed () const { return m_next - m_begin; }
  int bytes_left () const { return m_bytes_left; }
  bool done () const { return !bytes_left (); }
  int display_cols_processed () const { return m_display_cols; }

  int process_next_codepoint (cpp_decoded_char *out);
  int advance_display_cols (int n);

 private:
  const char *const m_begin;
  const char *m_next;
  size_t m_bytes_left;
  const cpp_char_column_policy &m_policy;
  int m_display_cols;
};

/* Convenience functions that are simple use cases for class
   cpp_display_width_computation.  Tab characters will be expanded to spaces
   as determined by POLICY.m_tabstop, and non-printable-ASCII characters
   will be escaped as per POLICY.  */

int cpp_byte_column_to_display_column (const char *data, int data_length,
				       int column,
				       const cpp_char_column_policy &policy);
inline int cpp_display_width (const char *data, int data_length,
			      const cpp_char_column_policy &policy)
{
  return cpp_byte_column_to_display_column (data, data_length, data_length,
					    policy);
}
int cpp_display_column_to_byte_column (const char *data, int data_length,
				       int display_col,
				       const cpp_char_column_policy &policy);
int cpp_wcwidth (cppchar_t c);

bool cpp_input_conversion_is_trivial (const char *input_charset);
int cpp_check_utf8_bom (const char *data, size_t data_length);
bool cpp_valid_utf8_p (const char *data, size_t num_bytes);

bool cpp_is_combining_char (cppchar_t c);
bool cpp_is_printable_char (cppchar_t c);

enum cpp_xid_property {
  CPP_XID_START = 1,
  CPP_XID_CONTINUE = 2
};

unsigned int cpp_check_xid_property (cppchar_t c);

/* In errors.cc */

/* RAII class to suppress CPP diagnostics in the current scope.  */
class cpp_auto_suppress_diagnostics
{
 public:
  explicit cpp_auto_suppress_diagnostics (cpp_reader *pfile);
  ~cpp_auto_suppress_diagnostics ();
 private:
  cpp_reader *const m_pfile;
  const decltype (cpp_callbacks::diagnostic) m_cb;
};

#endif /* ! LIBCPP_CPPLIB_H */