BCB5 Stack overflow problem

I am trying to pass a parameter via the constructor of a TForm but I get a Stack overflow error ?

I have used this method before but not with an integer as a parameter and have had no problems.

Any ideas wy I get the error ? The error is easily demonstrated by the following trivial code:

//header file unit1.h
#ifndef Unit1H
#define Unit1H
//---------------------------------------------------------------------------
#include <Classes.hpp>
#include <Controls.hpp>
#include <StdCtrls.hpp>
#include <Forms.hpp>
//---------------------------------------------------------------------------
class TForm1 : public TForm
{
__published:      // IDE-managed Components
    TButton *Button1;
    void __fastcall Button1Click(TObject *Sender);
private:      // User declarations
public:            // User declarations
    __fastcall TForm1(TComponent* Owner);
};
//---------------------------------------------------------------------------
extern PACKAGE TForm1 *Form1;
//---------------------------------------------------------------------------
#endif
// end of unit1.h

// unit1.cpp file
#include <vcl.h>
#pragma hdrstop

#include "Unit1.h"
#include "Unit2.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
    : TForm(Owner)
{
}
//---------------------------------------------------------------------------
void __fastcall TForm1::Button1Click(TObject *Sender)
{
    TForm2 *f;

    f = new TForm2(NULL,2);
    delete f;
}
//---------------------------------------------------------------------------
// end of unit1.cpp file

//unit2.h file
#ifndef Unit2H
#define Unit2H
//---------------------------------------------------------------------------
#include <Classes.hpp>
#include <Controls.hpp>
#include <StdCtrls.hpp>
#include <Forms.hpp>
//---------------------------------------------------------------------------
class TForm2 : public TForm
{
__published:      // IDE-managed Components
private:      // User declarations
public:            // User declarations
    __fastcall TForm2(TComponent* Owner,int n=0);
};
//---------------------------------------------------------------------------
extern PACKAGE TForm2 *Form2;
//---------------------------------------------------------------------------
#endif
//end of unit2.h file

//unit2.cpp file
#include <vcl.h>
#pragma hdrstop

#include "Unit2.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm2 *Form2;
//---------------------------------------------------------------------------
__fastcall TForm2::TForm2(TComponent* Owner,int n)
    : TForm(Owner)
{
}
//---------------------------------------------------------------------------
// end of unit2.cpp file



LVL 2
alcindorAsked:
Who is Participating?
 
rmmciConnect With a Mentor Commented:
when TForm 2 is created it calls
#pragma option push -w-inl
/* TCustomForm.Create */ inline __fastcall virtual TForm(Classes::TComponent* AOwner) : TCustomForm(AOwner) { }
from Forms.hpp and your getting the Int overflow by adding the int in the creation of
__fastcall TForm2::TForm2(TComponent* Owner,int n)
    : TForm(Owner)
causeing the stack over flow.
A better solution would be to pass via class in the public portion of the class.
0
 
alcindorAuthor Commented:
Hello rmmci,
My solution was to pass an int * as the argument which doesn't give the stack overflow and works just fine. I have used this method several times before but always passing a pointer as the argument (usually a pointer to a structure).
The points are yours, I am curious as to why it is ok to use a pointer argument but not an int ?

Thanks for your input,

Roger
0
All Courses

From novice to tech pro — start learning today.