What is the term used for the act of casting a void pointer into a pointer to a type?

Question

What is the term used (say, by programming language theorists) for the act of casting a void pointer into a pointer to a type? Is it "upcasting"? "type infusion"? "typing"?

Notes:

It is obviously a cast, and obviously a reinterpreting cast - but I'm looking for a more specific term, expressive of the transition from an untyped to a typed pointee.
Please do not argue about whether it's a good idea to avoid this or not, that is really not the question.

It's a cast IMO. A pointer to void is a type, and a pointer to int, ie, is another type. So with void `*p=NULL; int *i = (int *)p;` I'm casting a void pointer to an int pointer. — Frankie_C, Feb 20 '16 at 19:23
@WeatherVane: The phrasing of your question, at least to me implied that your statement held true for C but not for C++. Otherwise why ask "C or C++?"? Never mind. — Lightness Races in Orbit, Feb 20 '16 at 20:19

score 2 · Accepted Answer · answered Feb 20 '16 at 19:47

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If you wanted to make up a new term, you could call it type unerasure.

answered Feb 20 '16 at 19:47

Lightness Races in Orbit

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That term is assuming the target type was once erased, which is not necessarily the case. – einpoklum Feb 20 '16 at 20:14
@einpoklum: How so? Is there some way of creating objects of type `void` that I'm not aware of? If you're referring to interpretation of serialised data then I submit that the original data still had a type, even if only by the as-if rule :) – Lightness Races in Orbit Feb 20 '16 at 20:20
Well, while it's probably/certainly the case something was cast into a void*, it's very possible the reinterpreting cast will not be back to that type. I might have had a char*, played with the bits, and ended up with a valid float at the target address. But, you know, I guess it's a good enough term on second thought. Accepted. – einpoklum May 10 '16 at 22:26
@einpoklum: _Type invention_ perhaps ;) – Lightness Races in Orbit May 10 '16 at 23:45

πάντα ῥεῖ · Answer 2 · 2016-02-20T19:55:23.837

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I'd say such is brute force casting (or just casting like the c nitpickers will call it) like it's represented in c++ with the proper reinterpret_cast<>, hence reinterpret casting.

edited Feb 20 '16 at 19:55

answered Feb 20 '16 at 19:21

πάντα ῥεῖ

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this is the correct answer. why the downvotes? it's a reinterpret cast, pure and simple. – Richard Hodges Feb 20 '16 at 19:29
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@RichardHodges It was foreseeable that answer will get downvotes. People don't like to hear what's the truth. – πάντα ῥεῖ Feb 20 '16 at 19:32
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ain't that the truth :) – Richard Hodges Feb 20 '16 at 19:33
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Not really a pun; rather it's a play on words. Nicely done, but I've reported it because it's the truth. ;) – erip Feb 20 '16 at 19:39
@πάνταῥεῖ: But `(int) my_crazy_typed_value` is also brute-force casting. I want to capture the point of there not being an implied type before the cast, and there being one afterwards. – einpoklum Feb 20 '16 at 19:55
@einpoklum That's still a _brute force_ reinterpret cast. I don't get what you're really after with your question. – πάντα ῥεῖ Feb 20 '16 at 19:58
@πάνταῥεῖ: It is indeed a "brute force cast". It is also a "cast". It is also a "computational action". I want the specific term, that's all. – einpoklum Feb 20 '16 at 20:01
@einpoklum _"I want the specific term, that's all."_ Regarding c++ it's the `reinterpret_cast<>`, regarding c it's just the _cast_. That simple. – πάντα ῥεῖ Feb 20 '16 at 20:07
No, it is not. You can reinterpret_cast between non-void types, or from non void to void etc. – einpoklum Feb 20 '16 at 20:13
@einpoklum _"No, it is not. You can reinterpret_cast between non-void types"_ And what?? Why do you think `void*` should be a special case? Clarify your question please to get better answers regarding your unclear concerns. – πάντα ῥεῖ Feb 20 '16 at 20:15
@πάνταῥεῖ: PreferenceBean understood it just fine. And "there is no well-known special term for that" is also an answer. – einpoklum Feb 20 '16 at 20:26
@einpoklum Well, then accept lightness answer, or improve your question with some essence of what you're really asking about. – πάντα ῥεῖ Feb 20 '16 at 20:31
Added a note. As for @PreferenceBean's answer, it's ok-ish, but I'm looking for something people use. – einpoklum Feb 20 '16 at 20:47
@einpoklum People use the term _cast_ or _reinterpret cast_ are you going to ask about opinions (which is off-topic)? – πάντα ῥεῖ Feb 20 '16 at 20:50
People _you know_ only use the general term. – einpoklum Feb 20 '16 at 21:03

What is the term used for the act of casting a void pointer into a pointer to a type?

2 Answers2