Do you always must check for bad_alloc whenever dynamically allocating memory?

Question

If new cannot find enough memory, it throws an exception. Do I absolutely always need to check for that? I never did that and had no issues, but now I've read you should do that. Or only in certain cases?

try
{
    pPos = new Vector2D(5,1);
}
catch(bad_alloc)
{
    // NO MEMORY!
}

Depends on whether you can recover from lack of memory. Most of the time, no. — Passer By, Nov 13 '18 at 03:12
You can catch `bad_alloc` and ask the user to [download more RAM](https://downloadmoreram.com/), — Henri Menke, Nov 13 '18 at 03:42

Peter Ruderman · Answer 1 · 2018-11-13T04:33:17.163

There's nothing special about bad_alloc, you can catch it or not as you would any other exception. It is unusual to catch it. You would only do that if you had some way to recover from the out-of-memory condition. But I think programs that are designed to deal with out-of-memory errors more commonly use the nothrow version of new instead:

pPos = new (std::nothrow) Vector2D(5,1);
if (!pPos) {
    // NO MEMORY!
}

Do you always must check for bad_alloc whenever dynamically allocating memory?

1 Answers1