Program crashes when trying to assign a value to a class variable

find.cpp

Code:

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void find(vector<macros> &m, file &f)
{
    char *c_file;
    c_file=new char[f.oldLength()];
    f.oldFile().copy(c_file, f.oldLength());
    for(int x=0;x<f.oldLength();x++)
    {
        if(c_file[x]=='#')
        {
            x++;
            if(isValidMacro(c_file,x))
            {
                x+=5;
                f.addMacro();
                m.push_back(macros());
                m[f.numOfMacros()].atLoc(x);
                m[f.numOfMacros()].toSymbol(getSymbol(c_file,x));
            }
        }
    }
}

string getSymbol(char *c_file, int &pos)
{
    stringstream ss_symbol;
    string symbol;
    do
    {
        pos++;
    }while(c_file[pos]!=' ');
    do
    {
        ss_symbol<<c_file[pos];
        pos++;
    }while(c_file[pos]!='('&&c_file[pos]!=' ');
    ss_symbol>>symbol;
    return symbol;
}

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macros.cpp (implementation file for the macros class, this function causes the crash)

Code:

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void macros::toSymbol(string newSymbol)
{
    pSymbol=newSymbol;
}

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macros.h (class declaration)

Code:

---

class macros
{
    public:
        macros();
        ~macros();
        void toSymbol(string newSymbol), toToken(string newToken), atLoc(int location);

        string symbol(), token(), args(int num);
        int numOfArgs(), loc();
    private:
        string pSymbol, pToken, *pArgs;
        int pNumOfArgs, pLocation;
};

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Starting with the find() function, everything appears to work fine. The Code::Blocks debugger stopped working for me and I'm not quite as good at using gdb manually.. But I can tell it's the line pSymbol=newSymbol; that's causing the crash. I did some checking and similar functions in the macro class cause a crash during variable assignment. I have no idea what this is about.

Thanks.

1. why are you using char array instead of vector of chars?
2. why are you using operator[] instead of at() to access your macros vector
3. after first m.push_back(macros()); your vector contains 1 element I suppose. What is the value of f.numOfMacros() - is it zero at this time?

Quote:

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Originally Posted by vart

1. why are you using char array instead of vector of chars?
2. why are you using operator[] instead of at() to access your macros vector
3. after first m.push_back(macros()); your vector contains 1 element I suppose. What is the value of f.numOfMacros() - is it zero at this time?

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1. Never thought of that but it's a good idea. I never had a problem with using pointers for dynamic arrays, so I always did that.
2. Didn't know the at() function existed/was preferred.
3. This is probably an issue, f.numOfMacros() would be returning 1 right now. That solved the problem, but I don't understand why it was crashing on the line in the class function instead of the line that tried to call the nonexistent part of the vector.