[vbox-dev] [PATCH 2/8] Fix an implicit conversion from pointer to bool

[Jung-uk Kim]

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On 03/26/2015 14:03, Michal Necasek wrote:
> 
> The question isn't whether a compiler can warn. The question is,
> why should it?

Although this specific code has absolutely no problem, compilers are
not smart enough to read authors' mind yet. ;-)

> What you quoted doesn't contradict what Frank said. There is a very
> well defined pointer to bool conversion. So what's the problem? Or
> in other words, what is the semantic difference between

The difference is

> if (ptr)

ptr is converted to bool type first

> and
> 
> if (ptr != NULL)

ptr is compared to nullptr (if NULL is correctly defined as nullptr).

Basically, the first is a conversion and the second is a comparison.

Jung-uk Kim
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