Max version of c++?

Questions
1

I want to add a c++ ecs library in my project(https://github.com/skypjack/entt). But this library need c++17 or c++14.
Now i use c++11 and it work in all platforms.

If i use c++17 will it work on all platforms? Or maybe i need to use another library?

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2

Give it a try. Add -std=c++17 to your compilation flags in ext.manifest. My guess is that it should work for most platforms.

platforms:
    arm64-ios:
        context:
            flags: ["-std=c++17"]
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3

I try, and it worked. But i am not sure, that it will worked without problems, on all platform)

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4

I am curious about that too. I think @Mathias_Westerdahl know the answer…

5

Our compilers are currently:

Clang 6.0 - iOS, OSX, Windows
GCC 5.4 - Linux
GCC 4.8 - Android
Emscripten 1.38.12 - HTML5

(edit: forgot the SDKs)
Windows - MSVC 2015
iOS 11.2
OSX - 10.13
Android - NDK 10e, Api Level 14, , BuildTools23.0.2, API

This is important to know, since that affects the ABI of the libraries.

We don’t currently specify any “-std=c++xx” flag ourselves, we rely on the default version of the compiler.

In the engine, we use no C+±xx features at all, And no STL. We’re mostly C.
This helps you add your own librares to it, since it lessens the risk of ABI version clashes.

But, a reminder, that if you write very C+±y extensions, with the latest fancy C++ version, others might not be able to use it, because they get ABI clashes.

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6

If you provide a compiled static library with c++xx features, it won’t clash with others, right?

7

Technically, GCC is mostly ABI-compatible between compiler versions and -std versions. From what I remember reading, C++11 introduced some ABI-incompatible changes, but libstdc++ is compatible with both the old ABI and the new ABI, so you shouldn’t get linker errors. The bigger issue is Android, where you can choose to link against a bunch of different stdc++ libs, which will definitely trigger linker errors if two native extensions require different standard libraries, for example.

I’m not sure providing a static C library wrapping the C++ behaviour might do the trick. The symbols are resolved at link time and an .a file is still just a collection of unlinked object files. A dynamic library exposing a C API should do the trick, though.

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