STL4015: The std::iterator class template is deprecated in C++17

[YHabotAetrex]

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Required Info
Camera Model	D415
Firmware Version	05.11.15.00
Operating System & Version	Win 10
Platform	PC
SDK Version	2.29.0
Language	C++ Visual Sudio 2019 v 16.5.4

Issue Description

Getting a build error in :
\Intel RealSense SDK 2.0\include\librealsense2\hpp\rs_frame.hpp(1102,38): error C4996: 'std::iterator<std::forward_iterator_tag,rs2::frame,ptrdiff_t,rs2::frame *,rs2::frame &>': warning STL4015: The std::iterator class template (used as a base class to provide typedefs) is deprecated in C++17. (The header is NOT deprecated.) The C++ Standard has never required user-defined iterators to derive from std::iterator. To fix this warning, stop deriving from std::iterator and start providing publicly accessible typedefs named iterator_category, value_type, difference_type, pointer, and reference. Note that value_type is required to be non-const, even for constant iterators. You can define _SILENCE_CXX17_ITERATOR_BASE_CLASS_DEPRECATION_WARNING or _SILENCE_ALL_CXX17_DEPRECATION_WARNINGS to acknowledge that you have received this warning.

[MartyG-RealSense]

I carefully considered how to label your request to determine how the RealSense team track it. As others have not reported it as something that is breaking their builds, I have labelled it as "Enhancement" (a 'feature request'). This case will remain open so that it can be tracked. I hope that this is a satisfactory approach for you.

[MartyG-RealSense]

There were no other reports from RealSense users of this problem occurring in the 2 months after this case was created. I will therefore close the case.

[danilogr]

Hey @MartyG-RealSense, would you mind re-opening this?

My info is similar to @YHabotAetrex, I am using RealSense2 on Windows with a C++17 compiler (Visual Studio v142).

I would also consider renaming this issue. std::iterator class is not deprecated in C++17. C++17 is deprecating inheriting from std::iterator.

The solution, for now, is to define _SILENCE_ALL_CXX17_DEPRECATION_WARNINGS, but it would be great to have C++17 compatible code. This blog has a really nice guide on the matter: https://www.fluentcpp.com/2018/05/08/std-iterator-deprecated/

[MartyG-RealSense]

@danilogr Ok, I will re-open it and take another look at it, as the details that you have kindly provided will be helpful for me to possibly file a bug report, given that it is a replicable problem (experienced by more than one RealSense user) and generates warnings.

[ev-mp]

@danilogr , @MartyG-RealSense , I will re-classify this as enhancement request - the SDK is explicitly targeted to C++11 standard.
Being compatible with the next versions of the language is envisaged, yet it is not the same as not being compliant with specifications.

[MartyG-RealSense]

Hi @YHabotAetrex and @danilogr The issue in this case has now been addressed with a Pull Request that has been merged into the RealSense SDK. I will therefore now close this case. Thanks very much for your reports!