Strange error during runtime

I made a fairly basic character by character string tokenizer. It seems to run fine except I get this strange error at the end of the program:

*** glibc detected *** ./order: free(): invalid pointer: 0xbffdd42c ***
======= Backtrace: =========
/lib/tls/i686/cmov/libc.so.6[0xb7d30a85]
/lib/tls/i686/cmov/libc.so.6(cfree+0x90)[0xb7d344f0]
/usr/lib/libstdc++.so.6(_ZdlPv+0x21)[0xb7efcb11]
/usr/lib/libstdc++.so.6(_ZNSs4_Rep10_M_destroyERKSaIcE+0x1d )[0xb7ed879d]
/usr/lib/libstdc++.so.6(_ZNSsD1Ev+0x51)[0xb7eda571]
./order[0x804ab42]
/lib/tls/i686/cmov/libc.so.6(__libc_start_main+0xe0)[0xb7cdb450]
./order(__gxx_personality_v0+0x69)[0x8048f61]
======= Memory map: ========
08048000-0804f000 r-xp 00000000 08:01 3137610 /home/hewhosurvives/c++/order/order
0804f000-08050000 rw-p 00006000 08:01 3137610 /home/hewhosurvives/c++/order/order
08050000-08071000 rw-p 08050000 00:00 0 [heap]
b7b00000-b7b21000 rw-p b7b00000 00:00 0
b7b21000-b7c00000 ---p b7b21000 00:00 0
b7cc4000-b7cc5000 rw-p b7cc4000 00:00 0
b7cc5000-b7e0e000 r-xp 00000000 08:01 4981802 /lib/tls/i686/cmov/libc-2.7.so
b7e0e000-b7e0f000 r--p 00149000 08:01 4981802 /lib/tls/i686/cmov/libc-2.7.so
b7e0f000-b7e11000 rw-p 0014a000 08:01 4981802 /lib/tls/i686/cmov/libc-2.7.so
b7e11000-b7e14000 rw-p b7e11000 00:00 0
b7e14000-b7e1e000 r-xp 00000000 08:01 4964364 /lib/libgcc_s.so.1
b7e1e000-b7e1f000 rw-p 0000a000 08:01 4964364 /lib/libgcc_s.so.1
b7e1f000-b7e20000 rw-p b7e1f000 00:00 0
b7e20000-b7e43000 r-xp 00000000 08:01 4981806 /lib/tls/i686/cmov/libm-2.7.so
b7e43000-b7e45000 rw-p 00023000 08:01 4981806 /lib/tls/i686/cmov/libm-2.7.so
b7e45000-b7f2d000 r-xp 00000000 08:01 549195 /usr/lib/libstdc++.so.6.0.9
b7f2d000-b7f30000 r--p 000e8000 08:01 549195 /usr/lib/libstdc++.so.6.0.9
b7f30000-b7f32000 rw-p 000eb000 08:01 549195 /usr/lib/libstdc++.so.6.0.9
b7f32000-b7f38000 rw-p b7f32000 00:00 0
b7f45000-b7f47000 rw-p b7f45000 00:00 0
b7f47000-b7f48000 r-xp b7f47000 00:00 0 [vdso]
b7f48000-b7f62000 r-xp 00000000 08:01 4964421 /lib/ld-2.7.so
b7f62000-b7f64000 rw-p 00019000 08:01 4964421 /lib/ld-2.7.so
bffc9000-bffde000 rw-p bffeb000 00:00 0 [stack]
Aborted


Anyone know how I can track down what is causing it?

>> free(): invalid pointer
Start looking at all your calls to free() (or delete).

gg

I haven't manually called either. Could using vectors and strings set that off?

Did you call a destructor explicitly?

here is most of the relavent code:

Code:

//THIS IS THE HEADER FILE
#include<string>
#include<fstream>
#include<vector>
//I know, don't do this in a header, but at this point I am just trying to get it to work
using namespace std;
class item
{
    public:
    /*
    This constructor accepts a string and creates an object with that name
    @parameter- inputName: The name of the of the item
    */
    item(string inputName);

    /*
    This function intializes a blank object
    */
    item();
    /*
    This function returns the name of the item
    @return: The name of the item
    */
    string getName() const;
    /*
    This function outputs the members of item
    @param stream: The stream the output is being written to
    @param inputItem:  The item that is being written to the stream
    @return: The outputstream
    */
    friend ostream &operator<<(ostream &stream, item inputItem);
    /*
    this function outputs the size of the name string followed by the name of the item to the stream given
    @param outputStream:  The stream to be written to
    */
    void save(ofstream &outputStream);
    /*
    This function inputs the size of the name vector and then loads the name vector
    @param inputStream: the file stream to be read from
    @return: Whether the load was successful or not
    */
    bool load(ifstream &inputStream);


    /*
    This function constructs an item with the contents of another item
    @param inputItem: The item to be copied from
    */
//    item(item const& inputItem);
    
    /*
    This operator assigns the values of another item to itself and returns a pointer to itself
    @param inputItem:  The item the values are being taken from
    @return:  a pointer to this item
    */
//    item& operator = (item &inputItem);
    private:
    string name;
};


    /*
    This constructor accepts a string and creates an object with that name
    @parameter- inputName: The name of the of the item
    */
item::item(string inputName)
{
    name=inputName;
}

    /*
    This function intializes a blank object
    */
    item::item()
{
}

    /*
    This function returns the name of the item
    @return: The name of the item
    */
string item::getName() const
{
    return name;
}
    /*
    This function outputs the members of item, first the length of the vector and then the vector name
    @param stream: The stream the output is being written to
    @param inputItem:  The item that is being written to the stream
    @return: The outputstream
    */
ostream &operator<<(ostream &stream, item inputItem)
{
    stream<<inputItem.name.length() << inputItem.name;
    return stream;
}

 /*
    this function outputs the size of the name string followed by the name of the item to the stream given
    @param outputStream:  The stream to be written to
    */
void item::save(ofstream &outputStream)
{
    outputStream << *this;
}
    /*
    This function inputs the size of the name vector and then loads the name vector
    @param inputStream: the file stream to be read from
    @return: Whether the load was successful or not
    */
    bool item::load(ifstream &inputStream)
    {
        int i;
        char ch;
        if(inputStream)
        {
            inputStream>>i;
        }
        else
        {
            return false;
        }
        for(int ii=0; ii<i && inputStream; ii++)
        {
            inputStream.get(ch);
            name.push_back(ch);
        }
        if(i!=name.length())
        {
            return false;
        }
        else
        {
            return true;
        }
    }

    /*
    This function constructs an item with the contents of another item
    @param inputItem: The item to be copied from
    */
/*
    item::item(item const& inputItem)
    {
    name=inputItem.getName();
    }
  */  
    /*
    This operator assigns the values of another item to itself and returns a pointer to itself
    @param inputItem:  The item the values are being taken from
    @return:  a pointer to this item
    */
/*
    item& item::operator = (item &inputItem)
    {
    name=inputItem.getName();
    return this*;
    }
*/




//This is a menu made of items
class itemMenu
{
public:
/*
This function loads all of the items in the file and saves them in the listOfItems
@Param inputStream: The file stream that the items are to be read from
*/
itemMenu(ifstream &inputStream);
/*
This loads an empty menu
*/
itemMenu();
/*
This function adds an item to the listOfItems
@param inputItem: the item to be added
*/
void addItem(item inputItem);
/*
This function erases the item with the given name in the listOfItems
@param itemName: The name of the item to be deleted
*/ 
void deleteItem(string itemName);

/*
This function erases the last item on the menu
*/
void deleteItem();

/*
This function couts all of the items in the listOfItems
*/
void showItems();

/*
This function saves all of the items in the listOfItems
@param outputStream: The file stream for the items to be saved to
*/
void saveMenu(ofstream &outputStream);

/*
This function returns a copy of an item in the menu and a blank item if the index is wrong
@param inputIndex:  The index of the item to be accessed
*/
item getItem(int inputIndex);
private:
vector<item> listOfItems;

};



/*
This function loads all of the items in the file and saves them in the listOfItems
@Param inputStream: The file stream that the items are to be read from
*/
itemMenu::itemMenu(ifstream &inputStream)
{
item null;
listOfItems.push_back(null);
while(listOfItems[listOfItems.size()-1].load(inputStream))
{
listOfItems.push_back(null);
}
listOfItems.pop_back();
}
/*
This loads an empty menu
*/
itemMenu::itemMenu()
{
}
/*
This function adds an item to the listOfItems
@param inputItem: the item to be added
*/
void itemMenu::addItem(item inputItem)
{
listOfItems.push_back(inputItem.getName());
}
/*
This function erases the item with the given name in the listOfItems
@param itemName: The name of the item to be deleted
*/ 
void itemMenu::deleteItem(string itemName)
{
for(int i=0; i<listOfItems.size(); i++)
{
if(listOfItems[i].getName()==itemName)
{
listOfItems.erase(listOfItems.begin()+i-1);
}
}
}

/*
This function erases the last item on the menu
*/
void itemMenu::deleteItem()
{
listOfItems.pop_back();
}

/*
This function couts all of the items in the listOfItems
*/
void itemMenu::showItems()
{
for(int i=0; i<listOfItems.size(); i++)
{
cout << listOfItems[i];
}
}

/*
This function saves all of the items in the listOfItems
@param outputStream: The file stream for the items to be saved to
*/
void itemMenu::saveMenu(ofstream &outputStream)
{
for(int i=0; i<listOfItems.size(); i++)
{
listOfItems[i].save(outputStream);
}
}

/*
This function returns a copy of an item in the menu and a blank item if the index is wrong
@param inputIndex:  The index of the item to be accessed
*/
item itemMenu::getItem(int inputIndex)
{
if(inputIndex<listOfItems.size())
{
return listOfItems.at(inputIndex);
}
else
{
item noName;
return noName;
}
}

class burgerMan
{
public:
/*
This function load's burgerMan's menu from the file so he can take orders
@param inputStream: the file stream with the menu items
*/
burgerMan(ifstream &inputStream);
/*
This function takes in a natural language restarant order and extracts the which order types are required and how much of each
@param inputString: The natural langauge request
@return: The order
*/
string takeOrder(string inputString);
private:
itemMenu menu;
};

/*
This function load's burgerMan's menu from the file so he can take orders
@param inputStream: the file stream with the menu items
*/
burgerMan::burgerMan(ifstream &inputStream):menu(inputStream)
{
}
/*
This function takes in a natural language restarant order and extracts the which order types are required and how much of each
@param inputString: The natural langauge request
@return: The order
*/
string burgerMan::takeOrder(string inputString)
{
bool numberActive=false;
vector<string> tokens;
bool whiteSpace=true;
string buffer;
//tokenizing
for(int i=0; i<inputString.size();i++)
{
if(inputString[i]!=' ')
{
if(whiteSpace)
{
buffer.append(1,inputString[i]);
tokens.push_back(buffer);
whiteSpace=false;
}
else
{
tokens[tokens.size()-1].append(1,inputString[i]);
}
}
else
{
whiteSpace=true;
buffer="";
}
}
for(int i=0; i<tokens.size(); i++)
{
cout << tokens[i]<<i << "\n";
}

}
 //THIS IS THE MAIN FILE
#include<fstream>
#include<iostream>
#include<string>
#include</home/hewhosurvives/c++/order/item.h>
#include</home/hewhosurvives/c++/order/functions.h>
using namespace std;
int main(int argc, char* argv[])
{

ifstream streamer("orderMenu");
burgerMan mani(streamer);
mani.takeOrder("This is a sentice.   this not.  Can you tell the difference?");
cout <<"\n";
return 0;
}

The takeOrder function of the burgerMan class has most of the code that actually get exicuted

Your takeOrder is supposed to return a string, but doesn't. Once I fix that to return void (VS wouldn't even let me compile it otherwise), I don't get a crash. Maybe I'll wander over to the mac, which is more like the setting you're in, and see whether that makes a difference.

Edit: Same deal here -- I get a segmentation fault if I run your code; if I change takeOrder to return void, everything's fine. Apparently it's the trying to destruct a string that you didn't return that is causing the problems. So if you do intend to return a string, later, then for now just return something (anything); otherwise change it to void. And read your compiler warnings!

That did it. Wow, GCC compiled that without error. Thanks.

Well, if by without error you mean:

Code:

temp.cpp: In member function ‘bool item::load(std::ifstream&)’:
temp.cpp:129: warning: comparison between signed and unsigned integer expressions
temp.cpp: In member function ‘void itemMenu::deleteItem(std::string)’:
temp.cpp:251: warning: comparison between signed and unsigned integer expressions
temp.cpp: In member function ‘void itemMenu::showItems()’:
temp.cpp:273: warning: comparison between signed and unsigned integer expressions
temp.cpp: In member function ‘void itemMenu::saveMenu(std::ofstream&)’:
temp.cpp:285: warning: comparison between signed and unsigned integer expressions
temp.cpp: In member function ‘item itemMenu::getItem(int)’:
temp.cpp:297: warning: comparison between signed and unsigned integer expressions
temp.cpp: In member function ‘std::string burgerMan::takeOrder(std::string)’:
temp.cpp:345: warning: comparison between signed and unsigned integer expressions
temp.cpp:366: warning: comparison between signed and unsigned integer expressions
temp.cpp:340: warning: unused variable ‘numberActive’
temp.cpp:371: warning: control reaches end of non-void function

(I put everything in one file, so your line numbers may vary.) But the one at the end is the big one (this time).