Why is std::is_pod deprecated in C++20?

c++ typetraits
skypjack picture skypjack · Jan 12, 2018 · Viewed 10.8k times · Source

std::is_pod will be probably deprecated in C++20.
What's the reason for this choice? What should I use in place of std::is_pod to know if a type is actually a POD?

Answer

D.J. Klomp picture D.J. Klomp · Jan 12, 2018

POD is being replaced with two categories that give more nuances. The c++ standard meeting in november 2017 had this to say about it:

Deprecating the notion of “plain old data” (POD). It has been replaced with two more nuanced categories of types, “trivial” and “standard-layout”. “POD” is equivalent to “trivial and standard layout”, but for many code patterns, a narrower restriction to just “trivial” or just “standard layout” is appropriate; to encourage such precision, the notion of “POD” was therefore deprecated. The library trait is_pod has also been deprecated correspondingly.

For simple data types use the is_standard_layout function, for trivial data types (such as simple structs) use the is_trivial function.

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