From: GAMMELJL AT SLU DOT EDU
Date: Thu, 16 Sep 1999 11:29:13 -0500 (CDT)
Subject: Problem with new malloc
To: djgpp AT delorie DOT com
Message-id: <01JG1BRFCFYQ8WYLEP@SLU.EDU>
Organization: SAINT LOUIS UNIVERSITY  St. Louis, MO
X-VMS-To: IN%"djgpp AT delorie DOT com"
MIME-version: 1.0
Reply-To: djgpp AT delorie DOT com

//     I am having a problem with the new malloc.c.
//When one uses the new malloc.c via the include statement
//at MARK below the program compiles but does not run.  When one
//removes the include statement, the program uses the old malloc
//(? malloc.h located in c:\djgpp\include), compiles and runs properly.
//Note: The new malloc.c may reside in some other directory
//than c:\djgpp\src\libc\stdlib on your machine (or, by now, it
//may be part of the Delorie distribution of its
//port of gnu to DOS, in which case you may not have the
//old malloc)
//The problem occurs only in connection with overloading an operator
//(such as +) to define how + applies to the members of a user
//defined class (zvector in the example below).
//Of course, it is possible that I am making some other error.
//If so, please tell me.

#include <iostream.h>
#include <stdio.h>
#include <stdlib.h>
#include <conio.h>
#include <math.h>

//#include "c:\djgpp\src\libc\ansi\stdlib\malloc.c"    //MARK

const int length=10;
const int lengthpad=length+0xa;  //padding in memory allocation

class zvector {
 public:
    unsigned int *s;
    zvector();
    ~zvector();
};

zvector::zvector()               //constructor for realmp
  {s = new unsigned int [lengthpad];} 

zvector::~zvector()             //destructor for realmp
  {delete[] s;}

zvector e;
zvector f;
zvector g;

zvector w1;
zvector w8;
zvector w9;

extern zvector operator+(zvector w8,zvector w9);

zvector operator+(zvector w8,zvector w9)  
{ int zi;
  for (zi=1;zi<length+1;zi++)
    {w1.s[zi+1]=w8.s[zi+1] + w9.s[zi+1];
    }
  return w1;
}


main()
 { int k,qqq;

   for (k=1;k<length+1;k++)
     {e.s[k+1]=k;
      f.s[k+1]=k+1;
     }

   cout<<"add the following two vectors"<<'\n';
   for (k=1;k<length+1;k++) cout<<e.s[k+1]<<" ";
   cout<<'\n';
   for (k=1;k<length+1;k++) cout<<f.s[k+1]<<" ";
   cout<<'\n';
   cout<<'\n';

   g=e+f;

   cout<<"the result is"<<'\n';
   for (k=1;k<length+1;k++) cout<<g.s[k+1]<<" ";
   cout<<'\n';
   cout<<'\n';

   g=f+e;

   cout<<"check that the overloaded + operator is commutative"<<'\n';
   for (k=1;k<length+1;k++) cout<<g.s[k+1]<<" ";

   return 0;
   
 }