segmentation fault on some linux machines

[kkuruvadi]

I have written the following code which gives a segmentation fault on the line delete[] string1;
This behavior is seen only on a few linux machines and I would like to know the reason behind this

#include<iostream>
using namespace std;
#include<string.h>
int main(int argc, char* argv[])
{
    char* string1 = new char[5800];
    char* str1 = "Peer =Peer";
    char* str2 = ": Realm=mnc301.mcc302.3gppnetwork.org ";
    char num[3]={'0','0','\0'};
    num[3]='\0';
    const char* sPtr =const_cast <char*>(&num[0]);
 
    for (int i =1; i<63; i++)
    {
        char* tempString = new char[strlen(str1)+strlen(str2)+(i/10+1)];
        strcpy(tempString,str1);
        num[0]='0'+(i/10);
        num[1]='0'+(i%10);
        strcat(tempString, sPtr);
        strcat(tempString, str2);
        if(i==1)
           strcpy(string1, tempString);
        else
            strcat(string1, tempString);
        cout<<"tempString="<<tempString<<endl;
        delete[] tempString;
    }
    cout<<"string="<< string1<<endl;
    cout<<"strlen of string="<<strlen(string1)<<endl;
    delete[] string1;
    return 0;
}
 

Thanks,
Krishna

[PanGalactic]

Because you have multiple buffer overruns of tempString. The math for computing its size makes no sense. Why on Earth would you do this rather than use std::string?

[helios]

Line 10 is overflowing the 'num' array.
tempString doesn't reserve space for the terminator character under all circumstances.

Not a bug, but line 9 could be rewritten as char num[]="00";.