Hello Everyone!
Took me some time to write this post since I was on travel for few days.
We met on Tuesday May 13 2025 and discuss std::uninitialized_xyz() function family.
The Agenda:
- Quiz
- Uninitialized is actually good!
- Constructing Objects Separately: Understanding `std::uninitialized_*
- Efficiently Managing Object Lifetime in C++
Meetup page for the event is here.
Thank you CLion JetBrains for sponsoring San Diego C++ Community! Very much appreciated!
Details
- Quiz – we went over cppquiz #298 and #334. #298 highlighted the implicit noexcept of destructors, while #334 was about UB when you have a function that should return a value but it does not.
- CLion is free for non-commercial usage! no more need for my 100% free coupons 🙂
- I still have few hardcover books to give away, ping me if you want it.
- The main talk was discussing:
- C++ Allocation vs Construction
- How to work with Uninitialized memory? Can it boost performance in some cases?
- Standard algorithms need constructed, existing objects (that have their lifetime started)
- For example – the usage of std::copy() vs std::uninitialized_copy()
- The motivation – avoiding wasted work!
- Many code examples, mentioning all kinds of std::uninitialized_xyz() functions.
- std::destroy(), std::destroy_at(), std::destroy_n()
- Exception safety gurantee!
- Using std::ranges::uninitialized_xyz()
The great book from Patrice is a great resource! read it!
Thank you for reading!
Kobi