malloc / new issue

Match0um

Hi !
Sorry for that, but as I am not a expert in programming, I am stucked here. :(

I wanted to take avantage of new/delete instead of malloc/free.

In an existing program, I had:

bufferSize = (int*)malloc(sizeof(int));

and I changed for:

int *bufferSize = new int();

Compilation is OK but programm crashes when I try to access bufferSize. Can someone kindly tell me if something is wrong in my new line ? :(

Thanks for your help / explanation

Christian Ehrlicher

First - where is the relation to Qt here?
Second - why do you want to create a single integer on the heap at all?
Third - you code does not show anything, especially not the place where it's crashing. Provide a minimal, compilable example so we can see what you're doing (wrong).

mchinand

Also, in your first (old) line of code, you don't declare the type of bufferSize ; is it a class member variable? In your second (new) line of code, you do declare the type, making it a local shadow variable (which should generate a compiler warning and/or c-tidy warning). If you try to reference bufferSize in another method, it would try to access the uninitialized member variable.

nagesh

@Match0um where is this declared?
int bufferSize;
if declared as member variable during initialization use like this..
bufferSize = new int(); //don't use int