Will using new (std::nothrow) mask exceptions thrown from a constructor?

Question

Assume the following code:

Foo* p = new (std::nothrow) Foo();

\'p\' will equal 0 if we are out of heap memory.

What happens if we a

Answer 1

No, it won't be. The nothrow only applies to the call to new, not to the constructor.

Answer 2

I just tried it. The exception does get through. If you run the following code:

#include <new>

class Foo
{
public:
    Foo()
    {
        throw 42;
    }
};


int main()
{
    Foo* foo = new(std::nothrow) Foo;

    return 0;
}

then you get the following output (on Linux anyway):

terminate called after throwing an instance of 'int'
Aborted

So, the exception does indeed get through in spite of the nothrow.

Answer 3

Foo's constructor can still throw exceptions and they will fall through.

The constructor is not called until after the memory is allocated.