Visual Studio expands the __cplusplus macro to 199711L by default regardless of C++ std being used.

[ttanguay]

https://learn.microsoft.com/en-us/cpp/build/reference/zc-cplusplus?view=msvc-170

Using the /Zc:__cplusplus compiler option forces visual studio to set this macro properly.

NOTE: I was able to add lockfree to a project with C++17 support using CPMAddPackage with the following:

CPMAddPackage(
    NAME lockfree
    GITHUB_REPOSITORY DNedic/lockfree
    GIT_TAG 2.0.2
)
if (lockfree_ADDED AND MSVC)
    target_compile_options(lockfree INTERFACE "/Zc:__cplusplus")
endif()

[DNedic]

Hello @ttanguay , thanks for the feedback. On first glance, this should be possible to integrate into our CMakeLists, however I'm interested if you would be able to test it, as I have never used MSVC.

[DNedic]

Apparently this cannot be fixed using CMake without affecting the linked targets, I've created a solution that checks for MSVC and then uses _MSVC_LANG. Please test it and provide feedback if you can.

[ttanguay]

I will check out your latest commit.

[ttanguay]

I tested with latest commit and the PopOptional method of spsc::Queue is now available in Visual Studio without needing that target_compile_options in CMake.

I am having some issues with the library when adding with CPMAddPackage. Everything works fine when I tested in main with a globally declared queue. But when I put the queue as a private member of a class I'm getting errors. Not sure if it's some conflict with another header I'm including or I just haven't linked the library in correctly. It works fine if I just include the header files for queue in the project directly. I'll try a few things. Do you have the proper cmake commands to add lockfree to a project using FetchContent... maybe i can use that instead and see if it's just a CPM issue.

Thanks.

[DNedic]

Thanks for the review, I will merge the PR, please open another issue for the CPM problem and post the output you're getting.

Please try the FetchContent with this code snippet:

Include(FetchContent)

FetchContent_Declare(
    lockfree
    GIT_REPOSITORY https://github.com/DNedic/lockfree.git
    GIT_TAG        2.0.2
)

FetchContent_MakeAvailable(lockfree)