Upgrade libtcod to 1.12.3

[abesto]

Things to note:

• The source tree layout of libtcod has changed between releases
• I'll clean up the .idea stuff, sorry about that
• I only tested with MSVC, but took my best guess at how to make stuff work on the other platforms as well
• I did not write safe wrappers for new functionality added in libtcod, or even FFI definitions
• Compiles, I've been developing against it for a few hours now, and nothing blew up yet

[tomassedovic]

Thanks! And sorry for the conflicts!

Updating Cargo.toml should be trivial and feel free to disregard any changes to sys_sdl2_c.c and use your version for now.

The CI issues are real. I've rebased this and got to the same issues. The Linux verison is using ANSI C, but this relies on C++ 14.

We need to replace this line with config.flag("-std=c++14");:

tcod-rs/tcod_sys/build.rs

Line 65 in 718d8d9

config.flag("-ansi");

(and similar in build_linux_dynamic, mingw and darwin)

That got me to build tcod-sys but tcod itself (the safe bindings) failed with a bunch of errors.

From the PR message, I'm not sure whether that's where you are (i.e. you're using tcod-sys directly) or whether you can actually build tcot itself and it just doesn't have the new libtcod stuff.

[abesto]

We need to replace this line with config.flag("-std=c++14")

Seems straightforward enough. I'll do it once I pick this up again, I'd guess in a couple of days.

That got me to build tcod-sys but tcod itself (the safe bindings) failed with a bunch of errors.

From the PR message, I'm not sure whether that's where you are (i.e. you're using tcod-sys directly) or whether you can actually build tcot itself and it just doesn't have the new libtcod stuff.

Oops, I'm starting to suspect I'd need to update the root-level Cargo.toml for tcod to pick up the new tcod-sys? I didn't touch the top-level Cargo.toml, and tcod compiled fine; I was surprised, but happy. Guess it's not that simple after all :)

[tomassedovic]

I think tcod should be picking up the new tcod-sys version. If building tcod works for you, it's possibly another linking issue somewhere.

I'm seeing the same issue when I do update the version to 5.1.0 locally.

[abesto]

I've just added c++14, and updated the top-level Cargo.toml as well for good measure. Could compile cleanly under Ubuntu (FWIW, in the Linux subsystem of Windows 10):

Compiling tcod-sys v5.3.0 (/mnt/c/Users/abesto/Documents/GitHub/tcod-rs/tcod_sys)
Compiling tcod v0.14.0 (/mnt/c/Users/abesto/Documents/GitHub/tcod-rs)
Finished dev [unoptimized + debuginfo] target(s) in 55.86s   

Let's see what CI thinks. If it's sad, I'll then try to reproduce on a proper Linux system.

Meanwhile, if it's easy for you to reproduce, it might be good to have a full build output with the errors from your env.

[abesto]

Huh, rebased to tomassedovic:master, getting build errors now. Lemme try to resolve them.

[abesto]

Bah, never mind, just messed up the conflict resolution of tcod_sys/libtcod/src/libtcod/sys_sdl2_c.cpp.

[abesto]

Meh, Travis fails because ... it seems to not know about C++14? I'm having trouble fully believing that, but then https://github.com/libtcod/libtcod/blob/master/.travis.yml is also doing some magic around selecting the compiler. I'm out of time to spend on tracking that down for today, help is appreciated; I will be coming back to this, but no promises on the timeline.

On Appveyor I'm seeing one success so far, second build is in progress, so it's starting to smell like a Win / Linux env difference.

[abesto]

Alright, so all this work got us a working cargo build on Travis Linux, but cargo test is failing, because ... one of the examples are ... not linking against stdlib? Either way, that's all for today.

What we learned:

• The current version of libtcod requires C++ 14, and the default C compiler on Travis doesn't do C++ 14. I've asked it to use another compiler that does.
• The SDL2 version shipped in the repositories up to (excluding) Ubuntu 18.04 (which is newer than the latest version available on Travis) is not recent enough to work with libtcod, complains about some RGB pixel scheme not being defined. Assuming that's the same compile error you were getting. I asked Travis (just like the Travis config of libtcod itself does) to fetch a recent-ish version of SDL2, and build against that.

[abesto]

We have a goodnews-badnews situation.

Good news: I managed to reproduce the issue locally, and found some leads to fixing it. Bad news: I couldn't fix it. Halp!

Details! I was almost right: the failure is due to not linking against stdc++, during static compilation specifically (see https://stackoverflow.com/questions/10906275/undefined-reference-to-stdios-baseinitinit). Accordingly, I tried adding config.flag("-lstdc++"); to relevant-looking places, but this does nothing (probably obvious, if I dug deeper into how the full build process here works).

However! It seems that linking against C++ libraries is not very easy in Rust today. The conversation at https://users.rust-lang.org/t/linking-against-c-dependencies/25099/4 is trying to solve a very similar problem. I've tried println!("cargo:rustc-link-lib=static=stdc++"); and received the same message as noted in that thread (error: could not find native static librarystdc++, perhaps an -L flag is missing?). They then mention static-nobundle (which only works on nightly Rust); unfortunately in our case this brings back the original compiler errors. The resolution in the thread seemed to be a combination of static-nobundle and ... moving from gcc to clang? I'm not 100% clear on that.

So at this point I think the problem is well identified, and I've showed a few "solutions" that don't work; I'm escalating to you all, hopefully at this point someone will go "right, you just need to X".

[HexDecimal]

Current maintainer of libtcod here.

The latest versions of libtcod had their C++ dependencies removed and can now be compiled without any C++ sources. You'll only need C99 support from the tool-chain.

[abesto]

Closing this in favor of #309 - there's more progress there, some great simplifications, and it also targets a newer libtcod release.