Back to Basics: C++ Smart Pointers - David Olsen - CppCon 2022

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Back to Basics: C++ Smart Pointers - David Olsen - CppCon 2022

Smart pointers were one of the many powerful additions to C++11, providing programmers with easy-to-use tools to help manage memory resources and avoid certain kinds of memory errors. This back-to-basics session will give you a solid foundation in smart pointers, explaining what smart pointers are in general and how to use the standard smart pointer types std::unique_ptr and std::shared_ptr. It will present a set of clear guidelines for when and how to use smart pointers. Attendees will leave this session having learned, among other things, how to write code that never leaks memory.
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David Olsen

David Olsen has more than two decades of software development experience in a variety of programming languages and development environments. For the last six years he has been the lead engineer for the NVIDIA HPC C++ compiler, focusing on running parallel algorithms on GPUs. He is a member of the ISO C++ committee, where he was the champion for the extended floating-point feature in C++23.
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#cppcon #programming #coding

[violetashopova]

THIS GUY! ... every talk he did i watched so far is worth its time in gold

[coolwinder]

This talk is too good, incredible information presented. I have used this talk to sprawl my research and understanding of mentioned topics. Thanks David, this is much appreciated!

[qksuna]

Excellent talk, thank you! Appreciate always revisiting some fundamentals.

[Bolpat]

I’m currently in the process of updating a pre-C++11 codebase and some rules I imposed to myself is:
* Never assert(ptr_parameter); If you find yourself doing this to a parameter, it should be a reference. If necessary, the caller must assert.
* never new and delete (“// transfers ownership” doesn’t cut it)
* For arrays, use container types (e.g. std::vector, std::array) and (custom type) ranges and iterators
Then, any T* is a nullable non-owner pointer to a single object. Exceptions apply when calling library functions I have no control over, but if _my_ function takes/returns a int* it expects/returns a nullable non-owner pointer to a single object.

[acur]

Great talk - thank you for the fundamentals here!

[Roibarkan]

48:20 the type-erased nature of shared_ptr deleters can sometimes relieve issues related to multiple heap situations, ensuring an object gets deleted from the heap it was allocated from

[aprasath]

Wonderful video!!! Very well explained covering lots of issues with usage as well.

[Bolpat]

6:32 I’d add that a raw pointer should be nullable. If it’s non-owning and points to a single object, if it’s also not supposed to be null, what’s the difference to a reference?

[oraz.]

The variable length arrays in the examples are ok?

[Roibarkan]

14:02, 29:17 (slightly advanced) note that self-move (e.g. “a=std::move(a);”) is not considered something that move-assignment should guard against. Copy-assignment should typically guard against self-assignment, and this is guaranteed for shared_ptr.

[flocela]

at 33:38 on line 2. "a" gets passed into the thread function's parameter "b". Wouldn't that increment count. There's no red arrow showing increment count on line 2. A bit hazy on this, if anyone would answer, that would be great!

[nhanNguyen-wofy]

9:29 unique pointer as member of class

[cunningham.s_law]

if a unique pointer is the same in memory as a raw pointer, does that mean that I can reinterpretcast a raw pointer as a unique pointer and have it call the destructor?

[rutabega]

I'd argue that the first two examples don't need smart pointers.. what's wrong with std::vector??

[leili]

35:38
some member of the committee should be ashamed of their inefficiency. they always use “pursuing perfection” as an excuse, but in fact they spent one three-year after another, and got one half-finished product after another

[pawello]

CppCon 2019 - Back to basics: Smart pointers. By Arthur O'Dwyer. What's the point of repeating the same topic three years later?

[Lalasoth]

As already pointed out (yes I know) this same topic was given by Arthur O'Dwyer three years ago. I check these out just in case there's something neat or new discussed.
The audio in this video is terrible I couldn't finish watching it.

[mwilby]

DId he fr just do an entire presentation reaeding a script

[agentstona]

THIS IS ALL A WASTE OF TIME JUST SWITCH TO RUST OR PYTHON where memory is automanaged for you .... WHY YOU wasting your time attempting to manage stuff that can be automated ....

[treyquattro]

pretty perfunctory talk. All the huffing and blowing made it seem that Mr. Olsen was doing it under duress. Maybe let someone with a bit more enthusiasm for the subject do it next time?