Re: Unable to compile in Visual C++

[Joel E. Denny]

On Fri, 19 Jun 2009, Ewa Rom wrote:

> %{
> int yylex();
> void yyerror(char *s);
>  #include "stdafx.h"
>  #include <stdio.h>
>  #include <iostream>
>  #include <stdlib.h>
>  #include <stdarg.h>
>  #include <string.h>
>  #include <fstream>
>  #include <windows.h>
>  #include <Shellapi.h>
>  #include "parser.hpp"
>  #include "resource.h"
> 
> nodeType *v(char s);
> nodeType *in(int i);
> nodeType *oper(char s,nodeType l,nodeType r);
> 
> void printToFile(char *s);
> 
> using namespace std;
> %}

>From the above block, try moving everything that the %union below depends 
upon to a %code requires.  I believe that's just:

  %code requires {
    #include "resource.h"
  }

> %union {
>  int iValue;
>  char sIndex;
>  nodeType *nPtr;
> }

> flex -olex.cpp CoProveLexer.lex
> bison -v -d --language=C++ -oparser.cpp CoProveParser.y
> 
>  
> 
> Which generates me lex.cpp parser.cpp and parser.hpp files that I have 
> included into my Visual C++ project.
> 
> Then I try to build the project and I get the following error:
> 
>  
> 
> 1>CoProveParser.y(28) : error C2143: syntax error : missing ';' before '*'
> 
> 1>CoProveParser.y(28) : error C4430: missing type specifier - int assumed. 
> Note: C++ does not support default-int
> 
> 1>CoProveParser.y(28) : error C4430: missing type specifier - int assumed. 
> Note: C++ does not support default-int

> It seems like the %union does not know about the definition of the 
> nodeType structure defined in the resource.h file even if I include it 
> in the first part of the y file enclosed by %{ %}

%{ %} does not generate code into the parser.hpp file.  Based on the 
information you've provided, I believe that's the problem you've 
encountered.  If so, the %code suggestion I gave above should fix it.

In general, you ought to consider using %code instead of the old %{ %} to 
avoid these kinds of issues.  See the %code entries in the section "Bison 
Declaration Summary" in the Bison manual for a summary of its 
functionality.  See the section "Prologue Alternatives" for a detailed 
discussion including the advantages of %code over %{ %}.

However, %code is not available in Bison 2.3a and earlier, so your 
grammars would only work with more recent versions of Bison.  If 
compatibility is a concern for you, we can discuss other solutions, but 
please try %code first to see if that fixes your problem.