4 questions
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Accessing objects of implicit lifetime type in the storage provided by std::allocator, before any explicit construction
This question rises for a discussion of the answer to another question about allocation in constexpr context.
cppreference states that std::allocator<T>::allocate(std::size_t n) allocates an ...
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5
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Why are [[no_unique_address]] members not transparently replaceable?
In the classic talk An (In-)Complete Guide to C++ Object Lifetimes by Jonathan Müller, there is a useful guideline as follows:
Q: When do I need to use std::launder?
A: When you want to re-use the ...
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1
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Searching for clarity about C++20 strict aliasing in a custom allocator for implicit lifetime types
Let's say I have an allocator which gives out entire cachelines per request.
So each allocation will begin on a new cacheline.
constexpr auto L1 = std::hardware_destructive_interference_size;
std::...
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8
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1
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An aggregate is implicit lifetime? Doesn't seem right
According to this and this an aggregate is implicit lifetime.
A class S is an implicit-lifetime class if it is an aggregate or has at least one trivial eligible constructor and a trivial, non-deleted ...
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