path: root/gdb/c-exp.y

/* YACC parser for C expressions, for GDB.
   Copyright 1986, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
   1998, 1999, 2000, 2003, 2004
   Free Software Foundation, Inc.

This file is part of GDB.

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 2 of the License, 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; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */

/* Parse a C expression from text in a string,
   and return the result as a  struct expression  pointer.
   That structure contains arithmetic operations in reverse polish,
   with constants represented by operations that are followed by special data.
   See expression.h for the details of the format.
   What is important here is that it can be built up sequentially
   during the process of parsing; the lower levels of the tree always
   come first in the result.

   Note that malloc's and realloc's in this file are transformed to
   xmalloc and xrealloc respectively by the same sed command in the
   makefile that remaps any other malloc/realloc inserted by the parser
   generator.  Doing this with #defines and trying to control the interaction
   with include files (<malloc.h> and <stdlib.h> for example) just became
   too messy, particularly when such includes can be inserted at random
   times by the parser generator.  */
   
%{

#include "defs.h"
#include "gdb_string.h"
#include <ctype.h>
#include "expression.h"
#include "value.h"
#include "parser-defs.h"
#include "language.h"
#include "c-lang.h"
#include "bfd.h" /* Required by objfiles.h.  */
#include "symfile.h" /* Required by objfiles.h.  */
#include "objfiles.h" /* For have_full_symbols and have_partial_symbols */
#include "charset.h"
#include "block.h"
#include "cp-support.h"

/* Remap normal yacc parser interface names (yyparse, yylex, yyerror, etc),
   as well as gratuitiously global symbol names, so we can have multiple
   yacc generated parsers in gdb.  Note that these are only the variables
   produced by yacc.  If other parser generators (bison, byacc, etc) produce
   additional global names that conflict at link time, then those parser
   generators need to be fixed instead of adding those names to this list. */

#define	yymaxdepth c_maxdepth
#define	yyparse	c_parse
#define	yylex	c_lex
#define	yyerror	c_error
#define	yylval	c_lval
#define	yychar	c_char
#define	yydebug	c_debug
#define	yypact	c_pact	
#define	yyr1	c_r1			
#define	yyr2	c_r2			
#define	yydef	c_def		
#define	yychk	c_chk		
#define	yypgo	c_pgo		
#define	yyact	c_act		
#define	yyexca	c_exca
#define yyerrflag c_errflag
#define yynerrs	c_nerrs
#define	yyps	c_ps
#define	yypv	c_pv
#define	yys	c_s
#define	yy_yys	c_yys
#define	yystate	c_state
#define	yytmp	c_tmp
#define	yyv	c_v
#define	yy_yyv	c_yyv
#define	yyval	c_val
#define	yylloc	c_lloc
#define yyreds	c_reds		/* With YYDEBUG defined */
#define yytoks	c_toks		/* With YYDEBUG defined */
#define yyname	c_name		/* With YYDEBUG defined */
#define yyrule	c_rule		/* With YYDEBUG defined */
#define yylhs	c_yylhs
#define yylen	c_yylen
#define yydefred c_yydefred
#define yydgoto	c_yydgoto
#define yysindex c_yysindex
#define yyrindex c_yyrindex
#define yygindex c_yygindex
#define yytable	 c_yytable
#define yycheck	 c_yycheck

#ifndef YYDEBUG
#define	YYDEBUG 1		/* Default to yydebug support */
#endif

#define YYFPRINTF parser_fprintf

int yyparse (void);

static int yylex (void);

void yyerror (char *);

%}

/* Although the yacc "value" of an expression is not used,
   since the result is stored in the structure being created,
   other node types do have values.  */

%union
  {
    LONGEST lval;
    struct {
      LONGEST val;
      struct type *type;
    } typed_val_int;
    struct {
      DOUBLEST dval;
      struct type *type;
    } typed_val_float;
    struct symbol *sym;
    struct type *tval;
    struct stoken sval;
    struct ttype tsym;
    struct symtoken ssym;
    int voidval;
    struct block *bval;
    enum exp_opcode opcode;
    struct internalvar *ivar;

    struct type **tvec;
    int *ivec;
  }

%{
/* YYSTYPE gets defined by %union */
static int parse_number (char *, int, int, YYSTYPE *);
%}

%type <voidval> exp exp1 type_exp start variable qualified_name lcurly
%type <lval> rcurly
%type <tval> type typebase qualified_type
%type <tvec> nonempty_typelist
/* %type <bval> block */

/* Fancy type parsing.  */
%type <voidval> func_mod direct_abs_decl abs_decl
%type <tval> ptype
%type <lval> array_mod

%token <typed_val_int> INT
%token <typed_val_float> FLOAT

/* Both NAME and TYPENAME tokens represent symbols in the input,
   and both convey their data as strings.
   But a TYPENAME is a string that happens to be defined as a typedef
   or builtin type name (such as int or char)
   and a NAME is any other symbol.
   Contexts where this distinction is not important can use the
   nonterminal "name", which matches either NAME or TYPENAME.  */

%token <sval> STRING
%token <ssym> NAME /* BLOCKNAME defined below to give it higher precedence. */
%token <tsym> TYPENAME
%type <sval> name
%type <ssym> name_not_typename
%type <tsym> typename

/* A NAME_OR_INT is a symbol which is not known in the symbol table,
   but which would parse as a valid number in the current input radix.
   E.g. "c" when input_radix==16.  Depending on the parse, it will be
   turned into a name or into a number.  */

%token <ssym> NAME_OR_INT 

%token STRUCT CLASS UNION ENUM SIZEOF UNSIGNED COLONCOLON
%token TEMPLATE
%token ERROR

/* Special type cases, put in to allow the parser to distinguish different
   legal basetypes.  */
%token SIGNED_KEYWORD LONG SHORT INT_KEYWORD CONST_KEYWORD VOLATILE_KEYWORD DOUBLE_KEYWORD

%token <voidval> VARIABLE

%token <opcode> ASSIGN_MODIFY

/* C++ */
%token TRUEKEYWORD
%token FALSEKEYWORD


%left ','
%left ABOVE_COMMA
%right '=' ASSIGN_MODIFY
%right '?'
%left OROR
%left ANDAND
%left '|'
%left '^'
%left '&'
%left EQUAL NOTEQUAL
%left '<' '>' LEQ GEQ
%left LSH RSH
%left '@'
%left '+' '-'
%left '*' '/' '%'
%right UNARY INCREMENT DECREMENT
%right ARROW '.' '[' '('
%token <ssym> BLOCKNAME 
%token <bval> FILENAME
%type <bval> block
%left COLONCOLON


%%

start   :	exp1
	|	type_exp
	;

type_exp:	type
			{ write_exp_elt_opcode(OP_TYPE);
			  write_exp_elt_type($1);
			  write_exp_elt_opcode(OP_TYPE);}
	;

/* Expressions, including the comma operator.  */
exp1	:	exp
	|	exp1 ',' exp
			{ write_exp_elt_opcode (BINOP_COMMA); }
	;

/* Expressions, not including the comma operator.  */
exp	:	'*' exp    %prec UNARY
			{ write_exp_elt_opcode (UNOP_IND); }
	;

exp	:	'&' exp    %prec UNARY
			{ write_exp_elt_opcode (UNOP_ADDR); }
	;

exp	:	'-' exp    %prec UNARY
			{ write_exp_elt_opcode (UNOP_NEG); }
	;

exp	:	'!' exp    %prec UNARY
			{ write_exp_elt_opcode (UNOP_LOGICAL_NOT); }
	;

exp	:	'~' exp    %prec UNARY
			{ write_exp_elt_opcode (UNOP_COMPLEMENT); }
	;

exp	:	INCREMENT exp    %prec UNARY
			{ write_exp_elt_opcode (UNOP_PREINCREMENT); }
	;

exp	:	DECREMENT exp    %prec UNARY
			{ write_exp_elt_opcode (UNOP_PREDECREMENT); }
	;

exp	:	exp INCREMENT    %prec UNARY
			{ write_exp_elt_opcode (UNOP_POSTINCREMENT); }
	;

exp	:	exp DECREMENT    %prec UNARY
			{ write_exp_elt_opcode (UNOP_POSTDECREMENT); }
	;

exp	:	SIZEOF exp       %prec UNARY
			{ write_exp_elt_opcode (UNOP_SIZEOF); }
	;

exp	:	exp ARROW name
			{ write_exp_elt_opcode (STRUCTOP_PTR);
			  write_exp_string ($3);
			  write_exp_elt_opcode (STRUCTOP_PTR); }
	;

exp	:	exp ARROW qualified_name
			{ /* exp->type::name becomes exp->*(&type::name) */
			  /* Note: this doesn't work if name is a
			     static member!  FIXME */
			  write_exp_elt_opcode (UNOP_ADDR);
			  write_exp_elt_opcode (STRUCTOP_MPTR); }
	;

exp	:	exp ARROW '*' exp
			{ write_exp_elt_opcode (STRUCTOP_MPTR); }
	;

exp	:	exp '.' name
			{ write_exp_elt_opcode (STRUCTOP_STRUCT);
			  write_exp_string ($3);
			  write_exp_elt_opcode (STRUCTOP_STRUCT); }
	;

exp	:	exp '.' qualified_name
			{ /* exp.type::name becomes exp.*(&type::name) */
			  /* Note: this doesn't work if name is a
			     static member!  FIXME */
			  write_exp_elt_opcode (UNOP_ADDR);
			  write_exp_elt_opcode (STRUCTOP_MEMBER); }
	;

exp	:	exp '.' '*' exp
			{ write_exp_elt_opcode (STRUCTOP_MEMBER); }
	;

exp	:	exp '[' exp1 ']'
			{ write_exp_elt_opcode (BINOP_SUBSCRIPT); }
	;

exp	:	exp '(' 
			/* This is to save the value of arglist_len
			   being accumulated by an outer function call.  */
			{ start_arglist (); }
		arglist ')'	%prec ARROW
			{ write_exp_elt_opcode (OP_FUNCALL);
			  write_exp_elt_longcst ((LONGEST) end_arglist ());
			  write_exp_elt_opcode (OP_FUNCALL); }
	;

lcurly	:	'{'
			{ start_arglist (); }
	;

arglist	:
	;

arglist	:	exp
			{ arglist_len = 1; }
	;

arglist	:	arglist ',' exp   %prec ABOVE_COMMA
			{ arglist_len++; }
	;

rcurly	:	'}'
			{ $$ = end_arglist () - 1; }
	;
exp	:	lcurly arglist rcurly	%prec ARROW
			{ write_exp_elt_opcode (OP_ARRAY);
			  write_exp_elt_longcst ((LONGEST) 0);
			  write_exp_elt_longcst ((LONGEST) $3);
			  write_exp_elt_opcode (OP_ARRAY); }
	;

exp	:	lcurly type rcurly exp  %prec UNARY
			{ write_exp_elt_opcode (UNOP_MEMVAL);
			  write_exp_elt_type ($2);
			  write_exp_elt_opcode (UNOP_MEMVAL); }
	;

exp	:	'(' type ')' exp  %prec UNARY
			{ write_exp_elt_opcode (UNOP_CAST);
			  write_exp_elt_type ($2);
			  write_exp_elt_opcode (UNOP_CAST); }
	;

exp	:	'(' exp1 ')'
			{ }
	;

/* Binary operators in order of decreasing precedence.  */

exp	:	exp '@' exp
			{ write_exp_elt_opcode (BINOP_REPEAT); }
	;

exp	:	exp '*' exp
			{ write_exp_elt_opcode (BINOP_MUL); }
	;

exp	:	exp '/' exp
			{ write_exp_elt_opcode (BINOP_DIV); }
	;

exp	:	exp '%' exp
			{ write_exp_elt_opcode (BINOP_REM); }
	;

exp	:	exp '+' exp
			{ write_exp_elt_opcode (BINOP_ADD); }
	;

exp	:	exp '-' exp
			{ write_exp_elt_opcode (BINOP_SUB); }
	;

exp	:	exp LSH exp
			{ write_exp_elt_opcode (BINOP_LSH); }
	;

exp	:	exp RSH exp
			{ write_exp_elt_opcode (BINOP_RSH); }
	;

exp	:	exp EQUAL exp
			{ write_exp_elt_opcode (BINOP_EQUAL); }
	;

exp	:	exp NOTEQUAL exp
			{ write_exp_elt_opcode (BINOP_NOTEQUAL); }
	;

exp	:	exp LEQ exp
			{ write_exp_elt_opcode (BINOP_LEQ); }
	;

exp	:	exp GEQ exp
			{ write_exp_elt_opcode (BINOP_GEQ); }
	;

exp	:	exp '<' exp
			{ write_exp_elt_opcode (BINOP_LESS); }
	;

exp	:	exp '>' exp
			{ write_exp_elt_opcode (BINOP_GTR); }
	;

exp	:	exp '&' exp
			{ write_exp_elt_opcode (BINOP_BITWISE_AND); }
	;

exp	:	exp '^' exp
			{ write_exp_elt_opcode (BINOP_BITWISE_XOR); }
	;

exp	:	exp '|' exp
			{ write_exp_elt_opcode (BINOP_BITWISE_IOR); }
	;

exp	:	exp ANDAND exp
			{ write_exp_elt_opcode (BINOP_LOGICAL_AND); }
	;

exp	:	exp OROR exp
			{ write_exp_elt_opcode (BINOP_LOGICAL_OR); }
	;

exp	:	exp '?' exp ':' exp	%prec '?'
			{ write_exp_elt_opcode (TERNOP_COND); }
	;
			  
exp	:	exp '=' exp
			{ write_exp_elt_opcode (BINOP_ASSIGN); }
	;

exp	:	exp ASSIGN_MODIFY exp
			{ write_exp_elt_opcode (BINOP_ASSIGN_MODIFY);
			  write_exp_elt_opcode ($2);
			  write_exp_elt_opcode (BINOP_ASSIGN_MODIFY); }
	;

exp	:	INT
			{ write_exp_elt_opcode (OP_LONG);
			  write_exp_elt_type ($1.type);
			  write_exp_elt_longcst ((LONGEST)($1.val));
			  write_exp_elt_opcode (OP_LONG); }
	;

exp	:	NAME_OR_INT
			{ YYSTYPE val;
			  parse_number ($1.stoken.ptr, $1.stoken.length, 0, &val);
			  write_exp_elt_opcode (OP_LONG);
			  write_exp_elt_type (val.typed_val_int.type);
			  write_exp_elt_longcst ((LONGEST)val.typed_val_int.val);
			  write_exp_elt_opcode (OP_LONG);
			}
	;


exp	:	FLOAT
			{ write_exp_elt_opcode (OP_DOUBLE);
			  write_exp_elt_type ($1.type);
			  write_exp_elt_dblcst ($1.dval);
			  write_exp_elt_opcode (OP_DOUBLE); }
	;

exp	:	variable
	;

exp	:	VARIABLE
			/* Already written by write_dollar_variable. */
	;

exp	:	SIZEOF '(' type ')'	%prec UNARY
			{ write_exp_elt_opcode (OP_LONG);
			  write_exp_elt_type (builtin_type_int);
			  CHECK_TYPEDEF ($3);
			  write_exp_elt_longcst ((LONGEST) TYPE_LENGTH ($3));
			  write_exp_elt_opcode (OP_LONG); }
	;

exp	:	STRING
			{ /* C strings are converted into array constants with
			     an explicit null byte added at the end.  Thus
			     the array upper bound is the string length.
			     There is no such thing in C as a completely empty
			     string. */
			  char *sp = $1.ptr; int count = $1.length;
			  while (count-- > 0)
			    {
			      write_exp_elt_opcode (OP_LONG);
			      write_exp_elt_type (builtin_type_char);
			      write_exp_elt_longcst ((LONGEST)(*sp++));
			      write_exp_elt_opcode (OP_LONG);
			    }
			  write_exp_elt_opcode (OP_LONG);
			  write_exp_elt_type (builtin_type_char);
			  write_exp_elt_longcst ((LONGEST)'\0');
			  write_exp_elt_opcode (OP_LONG);
			  write_exp_elt_opcode (OP_ARRAY);
			  write_exp_elt_longcst ((LONGEST) 0);
			  write_exp_elt_longcst ((LONGEST) ($1.length));
			  write_exp_elt_opcode (OP_ARRAY); }
	;

/* C++.  */
exp     :       TRUEKEYWORD    
                        { write_exp_elt_opcode (OP_LONG);
                          write_exp_elt_type (builtin_type_bool);
                          write_exp_elt_longcst ((LONGEST) 1);
                          write_exp_elt_opcode (OP_LONG); }
	;

exp     :       FALSEKEYWORD   
                        { write_exp_elt_opcode (OP_LONG);
                          write_exp_elt_type (builtin_type_bool);
                          write_exp_elt_longcst ((LONGEST) 0);
                          write_exp_elt_opcode (OP_LONG); }
	;

/* end of C++.  */

block	:	BLOCKNAME
			{
			  if ($1.sym)
			    $$ = SYMBOL_BLOCK_VALUE ($1.sym);
			  else
			    error ("No file or function \"%s\".",
				   copy_name ($1.stoken));
			}
	|	FILENAME
			{
			  $$ = $1;
			}
	;

block	:	block COLONCOLON name
			{ struct symbol *tem
			    = lookup_symbol (copy_name ($3), $1,
					     VAR_DOMAIN, (int *) NULL,
					     (struct symtab **) NULL);
			  if (!tem || SYMBOL_CLASS (tem) != LOC_BLOCK)
			    error ("No function \"%s\" in specified context.",
				   copy_name ($3));
			  $$ = SYMBOL_BLOCK_VALUE (tem); }
	;

variable:	block COLONCOLON name
			{ struct symbol *sym;
			  sym = lookup_symbol (copy_name ($3), $1,
					       VAR_DOMAIN, (int *) NULL,
					       (struct symtab **) NULL);
			  if (sym == 0)
			    error ("No symbol \"%s\" in specified context.",
				   copy_name ($3));

			  write_exp_elt_opcode (OP_VAR_VALUE);
			  /* block_found is set by lookup_symbol.  */
			  write_exp_elt_block (block_found);
			  write_exp_elt_sym (sym);
			  write_exp_elt_opcode (OP_VAR_VALUE); }
	;

qualified_name:	typebase COLONCOLON name
			{
			  struct type *type = $1;
			  if (TYPE_CODE (type) != TYPE_CODE_STRUCT
			      && TYPE_CODE (type) != TYPE_CODE_UNION
			      && TYPE_CODE (type) != TYPE_CODE_NAMESPACE)
			    error ("`%s' is not defined as an aggregate type.",
				   TYPE_NAME (type));

			  write_exp_elt_opcode (OP_SCOPE);
			  write_exp_elt_type (type);
			  write_exp_string ($3);
			  write_exp_elt_opcode (OP_SCOPE);
			}
	|	typebase COLONCOLON '~' name
			{
			  struct type *type = $1;
			  struct stoken tmp_token;
			  if (TYPE_CODE (type) != TYPE_CODE_STRUCT
			      && TYPE_CODE (type) != TYPE_CODE_UNION
			      && TYPE_CODE (type) != TYPE_CODE_NAMESPACE)
			    error ("`%s' is not defined as an aggregate type.",
				   TYPE_NAME (type));

			  tmp_token.ptr = (char*) alloca ($4.length + 2);
			  tmp_token.length = $4.length + 1;
			  tmp_token.ptr[0] = '~';
			  memcpy (tmp_token.ptr+1, $4.ptr, $4.length);
			  tmp_token.ptr[tmp_token.length] = 0;

			  /* Check for valid destructor name.  */
			  destructor_name_p (tmp_token.ptr, type);
			  write_exp_elt_opcode (OP_SCOPE);
			  write_exp_elt_type (type);
			  write_exp_string (tmp_token);
			  write_exp_elt_opcode (OP_SCOPE);
			}
	;

variable:	qualified_name
	|	COLONCOLON name
			{
			  char *name = copy_name ($2);
			  struct symbol *sym;
			  struct minimal_symbol *msymbol;

			  sym =
			    lookup_symbol (name, (const struct block *) NULL,
					   VAR_DOMAIN, (int *) NULL,
					   (struct symtab **) NULL);
			  if (sym)
			    {
			      write_exp_elt_opcode (OP_VAR_VALUE);
			      write_exp_elt_block (NULL);
			      write_exp_elt_sym (sym);
			      write_exp_elt_opcode (OP_VAR_VALUE);
			      break;
			    }

			  msymbol = lookup_minimal_symbol (name, NULL, NULL);
			  if (msymbol != NULL)
			    {
			      write_exp_msymbol (msymbol,
						 lookup_function_type (builtin_type_int),
						 builtin_type_int);
			    }
			  else
			    if (!have_full_symbols () && !have_partial_symbols ())
			      error ("No symbol table is loaded.  Use the \"file\" command.");
			    else
			      error ("No symbol \"%s\" in current context.", name);
			}
	;

variable:	name_not_typename
			{ struct symbol *sym = $1.sym;

			  if (sym)
			    {
			      if (symbol_read_needs_frame (sym))
				{
				  if (innermost_block == 0 ||
				      contained_in (block_found, 
						    innermost_block))
				    innermost_block = block_found;
				}

			      write_exp_elt_opcode (OP_VAR_VALUE);
			      /* We want to use the selected frame, not
				 another more inner frame which happens to
				 be in the same block.  */
			      write_exp_elt_block (NULL);
			      write_exp_elt_sym (sym);
			      write_exp_elt_opcode (OP_VAR_VALUE);
			    }
			  else if ($1.is_a_field_of_this)
			    {
			      /* C++: it hangs off of `this'.  Must
			         not inadvertently convert from a method call
				 to data ref.  */
			      if (innermost_block == 0 || 
				  contained_in (block_found, innermost_block))
				innermost_block = block_found;
			      write_exp_elt_opcode (OP_THIS);
			      write_exp_elt_opcode (OP_THIS);
			      write_exp_elt_opcode (STRUCTOP_PTR);
			      write_exp_string ($1.stoken);
			      write_exp_elt_opcode (STRUCTOP_PTR);
			    }
			  else
			    {
			      struct minimal_symbol *msymbol;
			      char *arg = copy_name ($1.stoken);

			      msymbol =
				lookup_minimal_symbol (arg, NULL, NULL);
			      if (msymbol != NULL)
				{
				  write_exp_msymbol (msymbol,
						     lookup_function_type (builtin_type_int),
						     builtin_type_int);
				}
			      else if (!have_full_symbols () && !have_partial_symbols ())
				error ("No symbol table is loaded.  Use the \"file\" command.");
			      else
				error ("No symbol \"%s\" in current context.",
				       copy_name ($1.stoken));
			    }
			}
	;

space_identifier : '@' NAME
		{ push_type_address_space (copy_name ($2.stoken));
		  push_type (tp_space_identifier);
		}
	;

const_or_volatile: const_or_volatile_noopt
	|
	;

cv_with_space_id : const_or_volatile space_identifier const_or_volatile
	;

const_or_volatile_or_space_identifier_noopt: cv_with_space_id
	| const_or_volatile_noopt 
	;

const_or_volatile_or_space_identifier: 
		const_or_volatile_or_space_identifier_noopt
	|
	;

abs_decl:	'*'
			{ push_type (tp_pointer); $$ = 0; }
	|	'*' abs_decl
			{ push_type (tp_pointer); $$ = $2; }
	|	'&'
			{ push_type (tp_reference); $$ = 0; }
	|	'&' abs_decl
			{ push_type (tp_reference); $$ = $2; }
	|	direct_abs_decl
	;

direct_abs_decl: '(' abs_decl ')'
			{ $$ = $2; }
	|	direct_abs_decl array_mod
			{
			  push_type_int ($2);
			  push_type (tp_array);
			}
	|	array_mod
			{
			  push_type_int ($1);
			  push_type (tp_array);
			  $$ = 0;
			}

	| 	direct_abs_decl func_mod
			{ push_type (tp_function); }
	|	func_mod
			{ push_type (tp_function); }
	;

array_mod:	'[' ']'
			{ $$ = -1; }
	|	'[' INT ']'
			{ $$ = $2.val; }
	;

func_mod:	'(' ')'
			{ $$ = 0; }
	|	'(' nonempty_typelist ')'
			{ free ($2); $$ = 0; }
	;

/* We used to try to recognize more pointer to member types here, but
   that didn't work (shift/reduce conflicts meant that these rules never
   got executed).  The problem is that
     int (foo::bar::baz::bizzle)
   is a function type but
     int (foo::bar::baz::bizzle::*)
   is a pointer to member type.  Stroustrup loses again!  */

type	:	ptype
	|	typebase COLONCOLON '*'
			{ $$ = lookup_member_type (builtin_type_int, $1); }
	;

typebase  /* Implements (approximately): (type-qualifier)* type-specifier */
	:	TYPENAME
			{ $$ = $1.type; }
	|	INT_KEYWORD
			{ $$ = builtin_type_int; }
	|	LONG
			{ $$ = builtin_type_long; }
	|	SHORT
			{ $$ = builtin_type_short; }
	|	LONG INT_KEYWORD
			{ $$ = builtin_type_long; }
	|	LONG SIGNED_KEYWORD INT_KEYWORD
			{ $$ = builtin_type_long; }
	|	LONG SIGNED_KEYWORD
			{ $$ = builtin_type_long; }
	|	SIGNED_KEYWORD LONG INT_KEYWORD
			{ $$ = builtin_type_long; }
	|	UNSIGNED LONG INT_KEYWORD
			{ $$ = builtin_type_unsigned_long; }
	|	LONG UNSIGNED INT_KEYWORD
			{ $$ = builtin_type_unsigned_long; }
	|	LONG UNSIGNED
			{ $$ = builtin_type_unsigned_long; }
	|	LONG LONG
			{ $$ = builtin_type_long_long; }
	|	LONG LONG INT_KEYWORD
			{ $$ = builtin_type_long_long; }
	|	LONG LONG SIGNED_KEYWORD INT_KEYWORD
			{ $$ = builtin_type_long_long; }
	|	LONG LONG SIGNED_KEYWORD
			{ $$ = builtin_type_long_long; }
	|	SIGNED_KEYWORD LONG LONG
			{ $$ = builtin_type_long_long; }
	|	SIGNED_KEYWORD LONG LONG INT_KEYWORD
			{ $$ = builtin_type_long_long; }
	|	UNSIGNED LONG LONG
			{ $$ = builtin_type_unsigned_long_long; }
	|	UNSIGNED LONG LONG INT_KEYWORD
			{ $$ = builtin_type_unsigned_long_long; }
	|	LONG LONG UNSIGNED
			{ $$ = builtin_type_unsigned_long_long; }
	|	LONG LONG UNSIGNED INT_KEYWORD
			{ $$ = builtin_type_unsigned_long_long; }
	|	SHORT INT_KEYWORD
			{ $$ = builtin_type_short; }
	|	SHORT SIGNED_KEYWORD INT_KEYWORD
			{ $$ = builtin_type_short; }
	|	SHORT SIGNED_KEYWORD
			{ $$ = builtin_type_short; }
	|	UNSIGNED SHORT INT_KEYWORD
			{ $$ = builtin_type_unsigned_short; }
	|	SHORT UNSIGNED 
			{ $$ = builtin_type_unsigned_short; }
	|	SHORT UNSIGNED INT_KEYWORD
			{ $$ = builtin_type_unsigned_short; }
	|	DOUBLE_KEYWORD
			{ $$ = builtin_type_double; }
	|	LONG DOUBLE_KEYWORD
			{ $$ = builtin_type_long_double; }
	|	STRUCT name
			{ $$ = lookup_struct (copy_name ($2),
					      expression_context_block); }
	|	CLASS name
			{ $$ = lookup_struct (copy_name ($2),
					      expression_context_block); }
	|	UNION name
			{ $$ = lookup_union (copy_name ($2),
					     expression_context_block); }
	|	ENUM name
			{ $$ = lookup_enum (copy_name ($2),
					    expression_context_block); }
	|	UNSIGNED typename
			{ $$ = lookup_unsigned_typename (TYPE_NAME($2.type)); }
	|	UNSIGNED
			{ $$ = builtin_type_unsigned_int; }
	|	SIGNED_KEYWORD typename
			{ $$ = lookup_signed_typename (TYPE_NAME($2.type)); }
	|	SIGNED_KEYWORD
			{ $$ = builtin_type_int; }
                /* It appears that this rule for templates is never
                   reduced; template recognition happens by lookahead
                   in the token processing code in yylex. */         
	|	TEMPLATE name '<' type '>'
			{ $$ = lookup_template_type(copy_name($2), $4,
						    expression_context_block);
			}
	| const_or_volatile_or_space_identifier_noopt typebase 
			{ $$ = follow_types ($2); }
	| typebase const_or_volatile_or_space_identifier_noopt 
			{ $$ = follow_types ($1); }
	| qualified_type
	;

/* FIXME: carlton/2003-09-25: This next bit leads to lots of
   reduce-reduce conflicts, because the parser doesn't know whether or
   not to use qualified_name or qualified_type: the rules are
   identical.  If the parser is parsing 'A::B::x', then, when it sees
   the second '::', it knows that the expression to the left of it has
   to be a type, so it uses qualified_type.  But if it is parsing just
   'A::B', then it doesn't have any way of knowing which rule to use,
   so there's a reduce-reduce conflict; it picks qualified_name, since
   that occurs earlier in this file than qualified_type.

   There's no good way to fix this with the grammar as it stands; as
   far as I can tell, some of the problems arise from ambiguities that
   GDB introduces ('start' can be either an expression or a type), but
   some of it is inherent to the nature of C++ (you want to treat the
   input "(FOO)" fairly differently depending on whether FOO is an
   expression or a type, and if FOO is a complex expression, this can
   be hard to determine at the right time).  Fortunately, it works
   pretty well in most cases.  For example, if you do 'ptype A::B',
   where A::B is a nested type, then the parser will mistakenly
   misidentify it as an expression; but evaluate_subexp will get
   called with 'noside' set to EVAL_AVOID_SIDE_EFFECTS, and everything
   will work out anyways.  But there are situations where the parser
   will get confused: the most common one that I've run into is when
   you want to do

     print *((A::B *) x)"

   where the parser doesn't realize that A::B has to be a type until
   it hits the first right paren, at which point it's too late.  (The
   workaround is to type "print *(('A::B' *) x)" instead.)  (And
   another solution is to fix our symbol-handling code so that the
   user never wants to type something like that in the first place,
   because we get all the types right without the user's help!)

   Perhaps we could fix this by making the lexer smarter.  Some of
   this functionality used to be in the lexer, but in a way that
   worked even less well than the current solution: that attempt
   involved having the parser sometimes handle '::' and having the
   lexer sometimes handle it, and without a clear division of
   responsibility, it quickly degenerated into a big mess.  Probably
   the eventual correct solution will give more of a role to the lexer
   (ideally via code that is shared between the lexer and
   decode_line_1), but I'm not holding my breath waiting for somebody
   to get around to cleaning this up...  */

qualified_type: typebase COLONCOLON name
		{
		  struct type *type = $1;
		  struct type *new_type;
		  char *ncopy = alloca ($3.length + 1);

		  memcpy (ncopy, $3.ptr, $3.length);
		  ncopy[$3.length] = '\0';

		  if (TYPE_CODE (type) != TYPE_CODE_STRUCT
		      && TYPE_CODE (type) != TYPE_CODE_UNION
		      && TYPE_CODE (type) != TYPE_CODE_NAMESPACE)
		    error ("`%s' is not defined as an aggregate type.",
			   TYPE_NAME (type));

		  new_type = cp_lookup_nested_type (type, ncopy,
						    expression_context_block);
		  if (new_type == NULL)
		    error ("No type \"%s\" within class or namespace \"%s\".",
			   ncopy, TYPE_NAME (type));
		  
		  $$ = new_type;
		}
	;

typename:	TYPENAME
	|	INT_KEYWORD
		{
		  $$.stoken.ptr = "int";
		  $$.stoken.length = 3;
		  $$.type = builtin_type_int;
		}
	|	LONG
		{
		  $$.stoken.ptr = "long";
		  $$.stoken.length = 4;
		  $$.type = builtin_type_long;
		}
	|	SHORT
		{
		  $$.stoken.ptr = "short";
		  $$.stoken.length = 5;
		  $$.type = builtin_type_short;
		}
	;

nonempty_typelist
	:	type
		{ $$ = (struct type **) malloc (sizeof (struct type *) * 2);
		  $<ivec>$[0] = 1;	/* Number of types in vector */
		  $$[1] = $1;
		}
	|	nonempty_typelist ',' type
		{ int len = sizeof (struct type *) * (++($<ivec>1[0]) + 1);
		  $$ = (struct type **) realloc ((char *) $1, len);
		  $$[$<ivec>$[0]] = $3;
		}
	;

ptype	:	typebase
	|	ptype const_or_volatile_or_space_identifier abs_decl const_or_volatile_or_space_identifier
		{ $$ = follow_types ($1); }
	;

const_and_volatile: 	CONST_KEYWORD VOLATILE_KEYWORD
	| 		VOLATILE_KEYWORD CONST_KEYWORD
	;

const_or_volatile_noopt:  	const_and_volatile 
			{ push_type (tp_const);
			  push_type (tp_volatile); 
			}
	| 		CONST_KEYWORD
			{ push_type (tp_const); }
	| 		VOLATILE_KEYWORD
			{ push_type (tp_volatile); }
	;

name	:	NAME { $$ = $1.stoken; }
	|	BLOCKNAME { $$ = $1.stoken; }
	|	TYPENAME { $$ = $1.stoken; }
	|	NAME_OR_INT  { $$ = $1.stoken; }
	;

name_not_typename :	NAME
	|	BLOCKNAME
/* These would be useful if name_not_typename was useful, but it is just
   a fake for "variable", so these cause reduce/reduce conflicts because
   the parser can't tell whether NAME_OR_INT is a name_not_typename (=variable,
   =exp) or just an exp.  If name_not_typename was ever used in an lvalue
   context where only a name could occur, this might be useful.
  	|	NAME_OR_INT
 */
	;

%%

/* Take care of parsing a number (anything that starts with a digit).
   Set yylval and return the token type; update lexptr.
   LEN is the number of characters in it.  */

/*** Needs some error checking for the float case ***/

static int
parse_number (p, len, parsed_float, putithere)
     char *p;
     int len;
     int parsed_float;
     YYSTYPE *putithere;
{
  /* FIXME: Shouldn't these be unsigned?  We don't deal with negative values
     here, and we do kind of silly things like cast to unsigned.  */
  LONGEST n = 0;
  LONGEST prevn = 0;
  ULONGEST un;

  int i = 0;
  int c;
  int base = input_radix;
  int unsigned_p = 0;

  /* Number of "L" suffixes encountered.  */
  int long_p = 0;

  /* We have found a "L" or "U" suffix.  */
  int found_suffix = 0;

  ULONGEST high_bit;
  struct type *signed_type;
  struct type *unsigned_type;

  if (parsed_float)
    {
      /* It's a float since it contains a point or an exponent.  */
      char c;
      int num = 0;	/* number of tokens scanned by scanf */
      char saved_char = p[len];

      p[len] = 0;	/* null-terminate the token */
      if (sizeof (putithere->typed_val_float.dval) <= sizeof (float))
	num = sscanf (p, "%g%c", (float *) &putithere->typed_val_float.dval,&c);
      else if (sizeof (putithere->typed_val_float.dval) <= sizeof (double))
	num = sscanf (p, "%lg%c", (double *) &putithere->typed_val_float.dval,&c);
      else
	{
#ifdef SCANF_HAS_LONG_DOUBLE
	  num = sscanf (p, "%Lg%c", &putithere->typed_val_float.dval,&c);
#else
	  /* Scan it into a double, then assign it to the long double.
	     This at least wins with values representable in the range
	     of doubles. */
	  double temp;
	  num = sscanf (p, "%lg%c", &temp,&c);
	  putithere->typed_val_float.dval = temp;
#endif
	}
      p[len] = saved_char;	/* restore the input stream */
      if (num != 1) 		/* check scanf found ONLY a float ... */
	return ERROR;
      /* See if it has `f' or `l' suffix (float or long double).  */

      c = tolower (p[len - 1]);

      if (c == 'f')
	putithere->typed_val_float.type = builtin_type_float;
      else if (c == 'l')
	putithere->typed_val_float.type = builtin_type_long_double;
      else if (isdigit (c) || c == '.')
	putithere->typed_val_float.type = builtin_type_double;
      else
	return ERROR;

      return FLOAT;
    }

  /* Handle base-switching prefixes 0x, 0t, 0d, 0 */
  if (p[0] == '0')
    switch (p[1])
      {
      case 'x':
      case 'X':
	if (len >= 3)
	  {
	    p += 2;
	    base = 16;
	    len -= 2;
	  }
	break;

      case 't':
      case 'T':
      case 'd':
      case 'D':
	if (len >= 3)
	  {
	    p += 2;
	    base = 10;
	    len -= 2;
	  }
	break;

      default:
	base = 8;
	break;
      }

  while (len-- > 0)
    {
      c = *p++;
      if (c >= 'A' && c <= 'Z')
	c += 'a' - 'A';
      if (c != 'l' && c != 'u')
	n *= base;
      if (c >= '0' && c <= '9')
	{
	  if (found_suffix)
	    return ERROR;
	  n += i = c - '0';
	}
      else
	{
	  if (base > 10 && c >= 'a' && c <= 'f')
	    {
	      if (found_suffix)
		return ERROR;
	      n += i = c - 'a' + 10;
	    }
	  else if (c == 'l')
	    {
	      ++long_p;
	      found_suffix = 1;
	    }
	  else if (c == 'u')
	    {
	      unsigned_p = 1;
	      found_suffix = 1;
	    }
	  else
	    return ERROR;	/* Char not a digit */
	}
      if (i >= base)
	return ERROR;		/* Invalid digit in this base */

      /* Portably test for overflow (only works for nonzero values, so make
	 a second check for zero).  FIXME: Can't we just make n and prevn
	 unsigned and avoid this?  */
      if (c != 'l' && c != 'u' && (prevn >= n) && n != 0)
	unsigned_p = 1;		/* Try something unsigned */

      /* Portably test for unsigned overflow.
	 FIXME: This check is wrong; for example it doesn't find overflow
	 on 0x123456789 when LONGEST is 32 bits.  */
      if (c != 'l' && c != 'u' && n != 0)
	{	
	  if ((unsigned_p && (ULONGEST) prevn >= (ULONGEST) n))
	    error ("Numeric constant too large.");
	}
      prevn = n;
    }

  /* An integer constant is an int, a long, or a long long.  An L
     suffix forces it to be long; an LL suffix forces it to be long
     long.  If not forced to a larger size, it gets the first type of
     the above that it fits in.  To figure out whether it fits, we
     shift it right and see whether anything remains.  Note that we
     can't shift sizeof (LONGEST) * HOST_CHAR_BIT bits or more in one
     operation, because many compilers will warn about such a shift
     (which always produces a zero result).  Sometimes TARGET_INT_BIT
     or TARGET_LONG_BIT will be that big, sometimes not.  To deal with
     the case where it is we just always shift the value more than
     once, with fewer bits each time.  */

  un = (ULONGEST)n >> 2;
  if (long_p == 0
      && (un >> (TARGET_INT_BIT - 2)) == 0)
    {
      high_bit = ((ULONGEST)1) << (TARGET_INT_BIT-1);

      /* A large decimal (not hex or octal) constant (between INT_MAX
	 and UINT_MAX) is a long or unsigned long, according to ANSI,
	 never an unsigned int, but this code treats it as unsigned
	 int.  This probably should be fixed.  GCC gives a warning on
	 such constants.  */

      unsigned_type = builtin_type_unsigned_int;
      signed_type = builtin_type_int;
    }
  else if (long_p <= 1
	   && (un >> (TARGET_LONG_BIT - 2)) == 0)
    {
      high_bit = ((ULONGEST)1) << (TARGET_LONG_BIT-1);
      unsigned_type = builtin_type_unsigned_long;
      signed_type = builtin_type_long;
    }
  else
    {
      int shift;
      if (sizeof (ULONGEST) * HOST_CHAR_BIT < TARGET_LONG_LONG_BIT)
	/* A long long does not fit in a LONGEST.  */
	shift = (sizeof (ULONGEST) * HOST_CHAR_BIT - 1);
      else
	shift = (TARGET_LONG_LONG_BIT - 1);
      high_bit = (ULONGEST) 1 << shift;
      unsigned_type = builtin_type_unsigned_long_long;
      signed_type = builtin_type_long_long;
    }

   putithere->typed_val_int.val = n;

   /* If the high bit of the worked out type is set then this number
      has to be unsigned. */

   if (unsigned_p || (n & high_bit)) 
     {
       putithere->typed_val_int.type = unsigned_type;
     }
   else 
     {
       putithere->typed_val_int.type = signed_type;
     }

   return INT;
}

struct token
{
  char *operator;
  int token;
  enum exp_opcode opcode;
};

static const struct token tokentab3[] =
  {
    {">>=", ASSIGN_MODIFY, BINOP_RSH},
    {"<<=", ASSIGN_MODIFY, BINOP_LSH}
  };

static const struct token tokentab2[] =
  {
    {"+=", ASSIGN_MODIFY, BINOP_ADD},
    {"-=", ASSIGN_MODIFY, BINOP_SUB},
    {"*=", ASSIGN_MODIFY, BINOP_MUL},
    {"/=", ASSIGN_MODIFY, BINOP_DIV},
    {"%=", ASSIGN_MODIFY, BINOP_REM},
    {"|=", ASSIGN_MODIFY, BINOP_BITWISE_IOR},
    {"&=", ASSIGN_MODIFY, BINOP_BITWISE_AND},
    {"^=", ASSIGN_MODIFY, BINOP_BITWISE_XOR},
    {"++", INCREMENT, BINOP_END},
    {"--", DECREMENT, BINOP_END},
    {"->", ARROW, BINOP_END},
    {"&&", ANDAND, BINOP_END},
    {"||", OROR, BINOP_END},
    {"::", COLONCOLON, BINOP_END},
    {"<<", LSH, BINOP_END},
    {">>", RSH, BINOP_END},
    {"==", EQUAL, BINOP_END},
    {"!=", NOTEQUAL, BINOP_END},
    {"<=", LEQ, BINOP_END},
    {">=", GEQ, BINOP_END}
  };

/* Read one token, getting characters through lexptr.  */

static int
yylex ()
{
  int c;
  int namelen;
  unsigned int i;
  char *tokstart;
  char *tokptr;
  int tempbufindex;
  static char *tempbuf;
  static int tempbufsize;
  struct symbol * sym_class = NULL;
  char * token_string = NULL;
  int class_prefix = 0;
  int unquoted_expr;
   
 retry:

  /* Check if this is a macro invocation that we need to expand.  */
  if (! scanning_macro_expansion ())
    {
      char *expanded = macro_expand_next (&lexptr,
                                          expression_macro_lookup_func,
                                          expression_macro_lookup_baton);

      if (expanded)
        scan_macro_expansion (expanded);
    }

  prev_lexptr = lexptr;
  unquoted_expr = 1;

  tokstart = lexptr;
  /* See if it is a special token of length 3.  */
  for (i = 0; i < sizeof tokentab3 / sizeof tokentab3[0]; i++)
    if (strncmp (tokstart, tokentab3[i].operator, 3) == 0)
      {
	lexptr += 3;
	yylval.opcode = tokentab3[i].opcode;
	return tokentab3[i].token;
      }

  /* See if it is a special token of length 2.  */
  for (i = 0; i < sizeof tokentab2 / sizeof tokentab2[0]; i++)
    if (strncmp (tokstart, tokentab2[i].operator, 2) == 0)
      {
	lexptr += 2;
	yylval.opcode = tokentab2[i].opcode;
	return tokentab2[i].token;
      }

  switch (c = *tokstart)
    {
    case 0:
      /* If we were just scanning the result of a macro expansion,
         then we need to resume scanning the original text.
         Otherwise, we were already scanning the original text, and
         we're really done.  */
      if (scanning_macro_expansion ())
        {
          finished_macro_expansion ();
          goto retry;
        }
      else
        return 0;

    case ' ':
    case '\t':
    case '\n':
      lexptr++;
      goto retry;

    case '\'':
      /* We either have a character constant ('0' or '\177' for example)
	 or we have a quoted symbol reference ('foo(int,int)' in C++
	 for example). */
      lexptr++;
      c = *lexptr++;
      if (c == '\\')
	c = parse_escape (&lexptr);
      else if (c == '\'')
	error ("Empty character constant.");
      else if (! host_char_to_target (c, &c))
        {
          int toklen = lexptr - tokstart + 1;
          char *tok = alloca (toklen + 1);
          memcpy (tok, tokstart, toklen);
          tok[toklen] = '\0';
          error ("There is no character corresponding to %s in the target "
                 "character set `%s'.", tok, target_charset ());
        }

      yylval.typed_val_int.val = c;
      yylval.typed_val_int.type = builtin_type_char;

      c = *lexptr++;
      if (c != '\'')
	{
	  namelen = skip_quoted (tokstart) - tokstart;
	  if (namelen > 2)
	    {
	      lexptr = tokstart + namelen;
              unquoted_expr = 0;
	      if (lexptr[-1] != '\'')
		error ("Unmatched single quote.");
	      namelen -= 2;
	      tokstart++;
	      goto tryname;
	    }
	  error ("Invalid character constant.");
	}
      return INT;

    case '(':
      paren_depth++;
      lexptr++;
      return c;

    case ')':
      if (paren_depth == 0)
	return 0;
      paren_depth--;
      lexptr++;
      return c;

    case ',':
      if (comma_terminates
          && paren_depth == 0
          && ! scanning_macro_expansion ())
	return 0;
      lexptr++;
      return c;

    case '.':
      /* Might be a floating point number.  */
      if (lexptr[1] < '0' || lexptr[1] > '9')
	goto symbol;		/* Nope, must be a symbol. */
      /* FALL THRU into number case.  */

    case '0':
    case '1':
    case '2':
    case '3':
    case '4':
    case '5':
    case '6':
    case '7':
    case '8':
    case '9':
      {
	/* It's a number.  */
	int got_dot = 0, got_e = 0, toktype;
	char *p = tokstart;
	int hex = input_radix > 10;

	if (c == '0' && (p[1] == 'x' || p[1] == 'X'))
	  {
	    p += 2;
	    hex = 1;
	  }
	else if (c == '0' && (p[1]=='t' || p[1]=='T' || p[1]=='d' || p[1]=='D'))
	  {
	    p += 2;
	    hex = 0;
	  }

	for (;; ++p)
	  {
	    /* This test includes !hex because 'e' is a valid hex digit
	       and thus does not indicate a floating point number when
	       the radix is hex.  */
	    if (!hex && !got_e && (*p == 'e' || *p == 'E'))
	      got_dot = got_e = 1;
	    /* This test does not include !hex, because a '.' always indicates
	       a decimal floating point number regardless of the radix.  */
	    else if (!got_dot && *p == '.')
	      got_dot = 1;
	    else if (got_e && (p[-1] == 'e' || p[-1] == 'E')
		     && (*p == '-' || *p == '+'))
	      /* This is the sign of the exponent, not the end of the
		 number.  */
	      continue;
	    /* We will take any letters or digits.  parse_number will
	       complain if past the radix, or if L or U are not final.  */
	    else if ((*p < '0' || *p > '9')
		     && ((*p < 'a' || *p > 'z')
				  && (*p < 'A' || *p > 'Z')))
	      break;
	  }
	toktype = parse_number (tokstart, p - tokstart, got_dot|got_e, &yylval);
        if (toktype == ERROR)
	  {
	    char *err_copy = (char *) alloca (p - tokstart + 1);

	    memcpy (err_copy, tokstart, p - tokstart);
	    err_copy[p - tokstart] = 0;
	    error ("Invalid number \"%s\".", err_copy);
	  }
	lexptr = p;
	return toktype;
      }

    case '+':
    case '-':
    case '*':
    case '/':
    case '%':
    case '|':
    case '&':
    case '^':
    case '~':
    case '!':
    case '@':
    case '<':
    case '>':
    case '[':
    case ']':
    case '?':
    case ':':
    case '=':
    case '{':
    case '}':
    symbol:
      lexptr++;
      return c;

    case '"':

      /* Build the gdb internal form of the input string in tempbuf,
	 translating any standard C escape forms seen.  Note that the
	 buffer is null byte terminated *only* for the convenience of
	 debugging gdb itself and printing the buffer contents when
	 the buffer contains no embedded nulls.  Gdb does not depend
	 upon the buffer being null byte terminated, it uses the length
	 string instead.  This allows gdb to handle C strings (as well
	 as strings in other languages) with embedded null bytes */

      tokptr = ++tokstart;
      tempbufindex = 0;

      do {
        char *char_start_pos = tokptr;

	/* Grow the static temp buffer if necessary, including allocating
	   the first one on demand. */
	if (tempbufindex + 1 >= tempbufsize)
	  {
	    tempbuf = (char *) realloc (tempbuf, tempbufsize += 64);
	  }
	switch (*tokptr)
	  {
	  case '\0':
	  case '"':
	    /* Do nothing, loop will terminate. */
	    break;
	  case '\\':
	    tokptr++;
	    c = parse_escape (&tokptr);
	    if (c == -1)
	      {
		continue;
	      }
	    tempbuf[tempbufindex++] = c;
	    break;
	  default:
	    c = *tokptr++;
            if (! host_char_to_target (c, &c))
              {
                int len = tokptr - char_start_pos;
                char *copy = alloca (len + 1);
                memcpy (copy, char_start_pos, len);
                copy[len] = '\0';

                error ("There is no character corresponding to `%s' "
                       "in the target character set `%s'.",
                       copy, target_charset ());
              }
            tempbuf[tempbufindex++] = c;
	    break;
	  }
      } while ((*tokptr != '"') && (*tokptr != '\0'));
      if (*tokptr++ != '"')
	{
	  error ("Unterminated string in expression.");
	}
      tempbuf[tempbufindex] = '\0';	/* See note above */
      yylval.sval.ptr = tempbuf;
      yylval.sval.length = tempbufindex;
      lexptr = tokptr;
      return (STRING);
    }

  if (!(c == '_' || c == '$'
	|| (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z')))
    /* We must have come across a bad character (e.g. ';').  */
    error ("Invalid character '%c' in expression.", c);

  /* It's a name.  See how long it is.  */
  namelen = 0;
  for (c = tokstart[namelen];
       (c == '_' || c == '$' || (c >= '0' && c <= '9')
	|| (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || c == '<');)
    {
      /* Template parameter lists are part of the name.
	 FIXME: This mishandles `print $a<4&&$a>3'.  */

      if (c == '<')
	{ 
               /* Scan ahead to get rest of the template specification.  Note
                  that we look ahead only when the '<' adjoins non-whitespace
                  characters; for comparison expressions, e.g. "a < b > c",
                  there must be spaces before the '<', etc. */
               
               char * p = find_template_name_end (tokstart + namelen);
               if (p)
                 namelen = p - tokstart;
               break;
	}
      c = tokstart[++namelen];
    }

  /* The token "if" terminates the expression and is NOT removed from
     the input stream.  It doesn't count if it appears in the
     expansion of a macro.  */
  if (namelen == 2
      && tokstart[0] == 'i'
      && tokstart[1] == 'f'
      && ! scanning_macro_expansion ())
    {
      return 0;
    }

  lexptr += namelen;

  tryname:

  /* Catch specific keywords.  Should be done with a data structure.  */
  switch (namelen)
    {
    case 8:
      if (strncmp (tokstart, "unsigned", 8) == 0)
	return UNSIGNED;
      if (current_language->la_language == language_cplus
	  && strncmp (tokstart, "template", 8) == 0)
	return TEMPLATE;
      if (strncmp (tokstart, "volatile", 8) == 0)
	return VOLATILE_KEYWORD;
      break;
    case 6:
      if (strncmp (tokstart, "struct", 6) == 0)
	return STRUCT;
      if (strncmp (tokstart, "signed", 6) == 0)
	return SIGNED_KEYWORD;
      if (strncmp (tokstart, "sizeof", 6) == 0)
	return SIZEOF;
      if (strncmp (tokstart, "double", 6) == 0)
	return DOUBLE_KEYWORD;
      break;
    case 5:
      if (current_language->la_language == language_cplus)
        {
          if (strncmp (tokstart, "false", 5) == 0)
            return FALSEKEYWORD;
          if (strncmp (tokstart, "class", 5) == 0)
            return CLASS;
        }
      if (strncmp (tokstart, "union", 5) == 0)
	return UNION;
      if (strncmp (tokstart, "short", 5) == 0)
	return SHORT;
      if (strncmp (tokstart, "const", 5) == 0)
	return CONST_KEYWORD;
      break;
    case 4:
      if (strncmp (tokstart, "enum", 4) == 0)
	return ENUM;
      if (strncmp (tokstart, "long", 4) == 0)
	return LONG;
      if (current_language->la_language == language_cplus)
          {
            if (strncmp (tokstart, "true", 4) == 0)
              return TRUEKEYWORD;
          }
      break;
    case 3:
      if (strncmp (tokstart, "int", 3) == 0)
	return INT_KEYWORD;
      break;
    default:
      break;
    }

  yylval.sval.ptr = tokstart;
  yylval.sval.length = namelen;

  if (*tokstart == '$')
    {
      write_dollar_variable (yylval.sval);
      return VARIABLE;
    }
  
  /* Look ahead and see if we can consume more of the input
     string to get a reasonable class/namespace spec or a
     fully-qualified name.  This is a kludge to get around the
     HP aCC compiler's generation of symbol names with embedded
     colons for namespace and nested classes. */

  /* NOTE: carlton/2003-09-24: I don't entirely understand the
     HP-specific code, either here or in linespec.  Having said that,
     I suspect that we're actually moving towards their model: we want
     symbols whose names are fully qualified, which matches the
     description above.  */
  if (unquoted_expr)
    {
      /* Only do it if not inside single quotes */ 
      sym_class = parse_nested_classes_for_hpacc (yylval.sval.ptr, yylval.sval.length,
                                                  &token_string, &class_prefix, &lexptr);
      if (sym_class)
        {
          /* Replace the current token with the bigger one we found */ 
          yylval.sval.ptr = token_string;
          yylval.sval.length = strlen (token_string);
        }
    }
  
  /* Use token-type BLOCKNAME for symbols that happen to be defined as
     functions or symtabs.  If this is not so, then ...
     Use token-type TYPENAME for symbols that happen to be defined
     currently as names of types; NAME for other symbols.
     The caller is not constrained to care about the distinction.  */
  {
    char *tmp = copy_name (yylval.sval);
    struct symbol *sym;
    int is_a_field_of_this = 0;
    int hextype;

    sym = lookup_symbol (tmp, expression_context_block,
			 VAR_DOMAIN,
			 current_language->la_language == language_cplus
			 ? &is_a_field_of_this : (int *) NULL,
			 (struct symtab **) NULL);
    /* Call lookup_symtab, not lookup_partial_symtab, in case there are
       no psymtabs (coff, xcoff, or some future change to blow away the
       psymtabs once once symbols are read).  */
    if (sym && SYMBOL_CLASS (sym) == LOC_BLOCK)
      {
	yylval.ssym.sym = sym;
	yylval.ssym.is_a_field_of_this = is_a_field_of_this;
	return BLOCKNAME;
      }
    else if (!sym)
      {				/* See if it's a file name. */
	struct symtab *symtab;

	symtab = lookup_symtab (tmp);

	if (symtab)
	  {
	    yylval.bval = BLOCKVECTOR_BLOCK (BLOCKVECTOR (symtab), STATIC_BLOCK);
	    return FILENAME;
	  }
      }

    if (sym && SYMBOL_CLASS (sym) == LOC_TYPEDEF)
        {
	  /* NOTE: carlton/2003-09-25: There used to be code here to
	     handle nested types.  It didn't work very well.  See the
	     comment before qualified_type for more info.  */
	  yylval.tsym.type = SYMBOL_TYPE (sym);
	  return TYPENAME;
        }
    if ((yylval.tsym.type = lookup_primitive_typename (tmp)) != 0)
      return TYPENAME;

    /* Input names that aren't symbols but ARE valid hex numbers,
       when the input radix permits them, can be names or numbers
       depending on the parse.  Note we support radixes > 16 here.  */
    if (!sym && 
        ((tokstart[0] >= 'a' && tokstart[0] < 'a' + input_radix - 10) ||
         (tokstart[0] >= 'A' && tokstart[0] < 'A' + input_radix - 10)))
      {
 	YYSTYPE newlval;	/* Its value is ignored.  */
	hextype = parse_number (tokstart, namelen, 0, &newlval);
	if (hextype == INT)
	  {
	    yylval.ssym.sym = sym;
	    yylval.ssym.is_a_field_of_this = is_a_field_of_this;
	    return NAME_OR_INT;
	  }
      }

    /* Any other kind of symbol */
    yylval.ssym.sym = sym;
    yylval.ssym.is_a_field_of_this = is_a_field_of_this;
    return NAME;
  }
}

void
yyerror (msg)
     char *msg;
{
  if (prev_lexptr)
    lexptr = prev_lexptr;

  error ("A %s in expression, near `%s'.", (msg ? msg : "error"), lexptr);
}