Header y.tab.h not found during compilation of lex.yy.c

Question

I am trying to create a basic compiler and I am facing some problems.

My flex code:

%{
    #include <stdio.h>
    #include "SymbolTable.h"
    #include <y.tab.h>

    //extern "C"
    //{
    //   extern int yylex(void);
    //   extern int yyparse(void);
    //}

    int line_count = 1;
    SymbolTable table;
    static int yywrap(void);

    void insert(const char* token, char* yytext) {
    ////printf ("%s: %s ", token, yytext);
    //printf ("%s ", token);
    SymbolInfo symbolInfo(yytext, token);
    table.insert(symbolInfo, line_count);
    }
    %}

    newLine         \n
    delim           [  \t]
    digit           [0-9]
    unsigned        {digit}+
    exponent        [eE][+-]?{unsigned}
    number          [-+]?({unsigned}|{unsigned}\.{unsigned}?|{unsigned}?\.{unsigned}){exponent}?
    letter          [A-Za-z]
    keyword         program|if|not|end|begin|else|then|do|while|function|Procedure|integer|real|var|oh|array|write|include
    id              (_|{letter})({letter}|{digit}|_)*
    header          {id}\.h
    sin_comment     \/\/.*
    mul_comment     "/*"(([^*]|(("*"+)[^*/]))*)("*"+)"/"
    string          \"(\\.|[^"])*\"
    char            \'(\\.|[^'])*\'
    addop           [\+-]|or
    mulop           [\*\/]|div|mod|and
    orop            ||
    leop            <=
    geop            >=
    eqop            ==
    neop            !=
    assignop        :=
    dotdot          \.\.
    brace           [\[\]\(\)]
    other           [,;:]
    hash            #
    err_dotdot      [0-9]+\.([0-9]+\.){1,}
    err_id          {digit}+{id}
    leftcurl        {
    rightcurl       }



    %%
    {newLine} {
    line_count++;
    }

    {string} {
    //printf ("str: %s\n", yytext);
    //printf ("line no: %d\n",line_count);
    //fprintf(tokenout,"\n<STRING, %s>\n",yytext);
    //fprintf(logout,"\nLine no %d: STRING <%s> found\n",line_count,yytext);
    }

    {char} {
    //printf ("str: %s\n", yytext);
    //printf ("line no: %d\n",line_count);
    //fprintf(tokenout,"\n<CHAR, %s>\n",yytext);
    //fprintf(logout,"\nLine no %d: CHAR <%s> found\n",line_count,yytext);
    }

    {keyword} {

    ////printf ("keyword");
    //fprintf(tokenout,"\n<KEYWORD, %s>\n",yytext);
    //fprintf(logout,"\nLine no %d: KEYWORD <%s> found\n",line_count,yytext);

    }

    {header} {
    insert("header",yytext);
    //fprintf(tokenout,"\n<HEADER %s>\n",yytext);
    //fprintf(logout,"\nLine no %d: HEADER <%s> found\n",line_count,yytext);

    }

    {id} {
    SymbolInfo symbolInfo(yytext, "ID");
    table.insert(symbolInfo, line_count);
    //printf ("id: %s\n", yytext); 
    //fprintf(tokenout,"<ID, %s>\n",yytext);
    //fprintf(logout,"\nLine no %d: ID <%s> found\n",line_count,yytext);
    }

    {sin_comment} {
    //printf ("\nSingleline comment found: %s\n",yytext);
    //fprintf(logout,"\nLine no %d: SINGLELINECOMMENTP <%s> found\n",line_count,yytext);
    }

    {mul_comment} {
    //printf ("\nMultiline comment found: %s\n",yytext);
    //fprintf(logout,"\nLine no %d: MULTILINECOMMENT <%s> found\n",line_count,yytext);
    }

    {number} {
    //printf ("number:%s\n",yytext);
    //printf ("line no: %d\n",line_count);
    SymbolInfo symbolInfo(yytext, "NUMBER");
    table.insert(symbolInfo, line_count);
    //fprintf(tokenout,"<NUMBER, %s>\n",yytext);
    //fprintf(logout,"\nLine no %d: NUMBER <%s> found\n",line_count,yytext);
    return NUMBER;

    }

    {addop} {
    insert("ADDOP", yytext);
    //printf ("line no: %d\n",line_count);
    //fprintf(tokenout,"\n<ADDOP, %s>\n",yytext);
    //fprintf(logout,"\nLine no %d: ADDOP <%s> found\n",line_count,yytext);
    return ADDOP;
    }

    {mulop} {
    insert("MULOP", yytext);
    //printf ("line no: %d\n",line_count);
    //fprintf(tokenout,"\n<MULOP, %s>\n",yytext);
    //fprintf(logout,"\nLine no %d: MULOP <%s> found\n",line_count,yytext);
    }

    {assignop} {
    insert("ASSIGNOP", yytext);
    //printf ("line no: %d\n",line_count);
    //fprintf(tokenout,"\n<ASSIGNOP, %s>\n",yytext);
    //fprintf(logout,"\nLine no %d: ASSIGNOP <%s> found\n",line_count,yytext);
    }


    {dotdot} {
    insert("DOTDOT", yytext);
    //printf ("line no: %d\n",line_count);
    }   
    {hash}  {
    insert("#",yytext);
    }

    {delim}+ {}

    {err_dotdot} {
    //printf ("Illegal usage of decimal\n");
    //fprintf(logout,"\nLine no %d: Illegal usage of decimal <%s> found\n",line_count,yytext);
    }

    {err_id} {
    //printf ("Illegal id\n");
    //fprintf(logout,"\nLine no %d: Illegal usage of id <%s> found\n",line_count,yytext);
    }

    %%

I can happily create lex.yy.c by lex -o lex.yy.c lex.l.

But when I try to create lex object file using g++ -c -w -o lexer.o lex.yy.c it says

lex.l:4:19: fatal error: y.tab.h: No such file or directory

I have already parsed the parser using bison -d -y grammar.y

Since `y.tab.h` is provided by *you*, not by the system, it would be conventional to use the quoted include form: `#include "y.tab.h"`. It's possible that that would even solve the problem. — John Bollinger, Dec 19 '16 at 03:02
Nope. There are things that are defined behavior in C, but either don't compile or are undefined behavior in C++. — druckermanly, Dec 19 '16 at 03:34
This is a compilation error. It has nothing to do with 'during lexical analysis', or [tag:compiler-construction] either. — user207421, Dec 19 '16 at 09:48
C++ is _almost_ a superset of C as it was defined in 1990. But any old ("K&R") or new ("C99") feature is a problem. That said, C++ does strive to make the intersection of C and C++ workable, but that's more to facilitate compatibility at library level. — MSalters, Dec 19 '16 at 13:13

ojblass · Accepted Answer · 2016-12-19T03:05:47.427

1

Change to "y.tab.h" in your code. In addition you might include a parameter to gcc to include the path to the file

g++ -c -w -I /path/to/header -o lexer.o lex.yy.c

edited Dec 19 '16 at 03:05

answered Dec 19 '16 at 03:01

ojblass

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The nature of the distinction between the two forms of `#include` directives is implementation-dependent. Depending on the the implementation, there might be no difference between the two forms at all, so it's a bit speculative to attribute any importance to it. – John Bollinger Dec 19 '16 at 03:05
Changing to "y.tab.h" solves this. Oh man, I wasted 1 day over this. Flex is a weird language. Owe you one. – desertSniper87 Dec 19 '16 at 03:28
@desertsniper87: That is C, not flex. It is usually a good idea to know how to write a C prigram *before* you start trying to use fkex/bison. – rici Dec 19 '16 at 04:22
1

@rici Having some typos in your text does not mean that you can't type. – desertSniper87 Dec 19 '16 at 04:56

Header y.tab.h not found during compilation of lex.yy.c

1 Answers1