@microsoft-github-policy-service agree

Hi @constcuriosity, thank you for the contribution. Unfortunately, all feature sets in ports should be side by side installable. This is implementing alternatives as features. See -> https://learn.microsoft.com/en-us/vcpkg/contributing/maintainer-guide#do-not-use-features-to-implement-alternatives

Currently, vcpkg install imgui[sdl2-binding,sdl3-binding] will not build.

Marking this vcpkg-team-review for a path forward.

Hi @JavierMatosD, thanks for taking a look at this pull request. I'll take a look at seeing if there's a way forward for these two features to compile together.

Do you know offhand if all of the directx version features are able to compile together? I'm just looking to extend the pattern that's already been established by the port.

Hi @JavierMatosD, thanks for taking a look at this pull request. I'll take a look at seeing if there's a way forward for these two features to compile together.

I spoke with my coworkers and it seems that the SDL project currently calls 2.x "current". See -> https://www.libsdl.org/. We think SDL2 should remain the canonical one for now. We encourage you to create an overlay port with this added functionality for your own purposes. See -> https://learn.microsoft.com/vcpkg/concepts/overlay-ports

Do you know offhand if all of the directx version features are able to compile together? I'm just looking to extend the pattern that's already been established by the port.

These features were probably added erroneously.

I'm closing this PR for now. Please feel free to reopen the PR if you feel we are mistaken.

I spoke with my coworkers and it seems that the SDL project currently calls 2.x "current". See -> https://www.libsdl.org/. We think SDL2 should remain the canonical one for now. We encourage you to create an overlay port with this added functionality for your own purposes. See -> https://learn.microsoft.com/vcpkg/concepts/overlay-ports

SDL3 has hit API and ABI lock as listed at https://wiki.libsdl.org/SDL3/FrontPage as well as in the formation of the sdl3 port a bit ago #40867. While not official yet, projects are now encouraged to move towards adoption of SDL3.

While you can have a vcpkg.json file that includes both sdl2 and sdl3, you can't follow the usage lines for both of them in your own cmake files. Doing so will have the 2nd library inclusion complain about a difference between the INTERFACE_SDL_VERSION and the SDL_VERSION of the next to-be-included library. And this is what causes the sdl2-binding and sdl3-binding incompatibility. Those features request either sdl2 or sdl3 as dependencies, and turning on both features will attempt to enforce that both are included, which triggers the above error.

This feels like it breaks the spirit of Ports in the current baseline must be installable simultaneously, since while you can technically install both SDL2 and SDL3 simultaneously, you can't have both of them as a dependency. If that was possible, then these features would work fine together.

Practically though... I don't know when that'd really happen. I think the vast majority of projects would only ever use one or the other. And same would go for these features on the imgui port. I guess the workaround would be to remove the dependency on each of the features, and rely on the project author add the dependencies themselves, but that's counter to the goal of vcpkg.

So with the TL;DR "It's not the features' fault, it's SDL2 and SDL3 incompatibility", I'd like to request an exception to the "no mutually exclusive features" policy. Making an overlay port would certainly work but it introduces a continuous maintenance burden by forking a frequently updated port (the version was even bumped within the short lifetime of this PR), and I believe the likelihood of a project purposefully including both SDL versions and both features to be very small.

Thanks for your time.

@JavierMatosD Sorry to ping you directly but it doesn't look like I have permission to re-open the PR myself.