Pro/con: Initializing a variable in a conditional statement

Question

In C++ you can initialize a variable in an if statement, like so:

if (CThing* pThing = GetThing())
{
}

Why would one consider this bad or g

Answer 1

Just an FYI some of the older Microsoft C++ compliers(Visual Studios 6, and .NET 2003 I think) don't quite follow the scoping rule in some instances.

for(int i = 0; i > 20; i++) {
     // some code
}

cout << i << endl;

I should be out of scope, but that was/is valid code. I believe it was played off as a feature, but in my opinion it's just non compliance. Not adhering to the standards is bad. Just as a web developer about IE and Firefox.

Can someone with VS check and see if that's still valid?