llvm-mingw VS glibc_version_header

> Doing Python with a C plugin, or just compiling a command line C/C++ isn't really systems programming.

I care about a minimal set of tools in order to compile C/C++ programs. thats offered by:

https://github.com/mstorsjo/llvm-mingw/releases

and also MSYS2, and even the Zig C compiler. all less than 200 MB. meanwhile Visual Studio installing about 10 GB worth. If Microsoft can offer a similar experience then I am interested.

Pick a community-supported Clang-based Mingw-w64 distribution.

> AFAIK there is no native GCC compiler for Windows

might want to check your facts before spouting nonsense. there is, and has been for many, many years. more than one in fact:

https://github.com/mstorsjo/llvm-mingw

https://packages.msys2.org/base/mingw-w64-gcc

MinGW is notoriously slow to link compared to MSVC, unless using llvm-mingw with the link=lld SCons option. If using MSVC, make sure to use 2022 or at least 2019 if possible – recent linkers tend to be faster than older versions.

GCC doesn't support windows/arm64, but you should be able to do it with LLVM. I've never gotten it to work myself, but should be able to supply a cross toolchain: https://github.com/mstorsjo/llvm-mingw

Visual Studio is a bloated mess, and has been for many years. Its at least 10 times larger than other options, such as MinGW-LLVM:

https://github.com/mstorsjo/llvm-mingw

Sadly Qt ships MinGW 8.1 which is positively ancient (released in 2018). If you're starting a new project (which you likely are if you are installing an IDE aha) there's no reason not to go for more recent compilers - msys2 has GCC12 (https://packages.msys2.org/package/mingw-w64-x86_64-gcc) and Clang 14 (https://packages.msys2.org/package/mingw-w64-x86_64-clang) which just work better overall, have much more complete C++20 support, have less bugs, better compile times (especially clang with the various PCH options that appeared in the last few versions), better static analysis, etc.

Personally I use https://github.com/mstorsjo/llvm-mingw's releases directly which does not require MSYS but that's because I recompile all my libraries with specific options - if the MSYS libs as they are built are good for you there's no reason not to use them.

you can grab it here: https://github.com/mstorsjo/llvm-mingw/releases/tag/20211002

Clang (and lld) do support native TLS, and mingw-w64 does have the things that are needed. I think binutils also might have what's needed too, but AFAIK the thing that's missing is support for it in GCC.

Actually, (upstream) Clang defaults to native TLS instead of emulated TLS. In MSYS2, Clang is overridden to use emulated TLS by deafult to interoperate better with GCC built code and libstdc++ though.

The toolchain I maintain, https://github.com/mstorsjo/llvm-mingw, defaults to native TLS throughout.

One major headache with trying to run precompiled binaries on Linux is that if they were compiled using a newer version of glibc than the target machine, they won't be able to run. Back while working on Factorio, I was trying to get around this problem with endless Docker containers, but coworker Wheybags came up with a much solution to this, which is simply to, at compile time, link to the oldest compatible version of glibc: https://github.com/wheybags/glibc_version_header

If what you're doing works for you, great, but in case it stops working at some point (or if for some reason you need to build on a current-gen distro version), you could also consider using this:

https://github.com/wheybags/glibc_version_header

It's a set of autogenerated headers that use symbol aliasing to allow you to build against your current version of glibc, but link to the proper older versioned symbols such that it will run on whatever oldest version of glibc you select.

There are other approaches like https://github.com/wheybags/glibc_version_header or sysroots with older glibc, e.g. https://wiki.gentoo.org/wiki/Crossdev - you don't need your whole XP, just the the system libs to link against.

Sure, having a nice SDK where you can just specify the minimum vesion you want to support would be nice but who do you expect to develop such an SDK? GNU/glibc maintainers? They would rather you ship as source. Red Hat / SUSE / Canonical? They want you to target only their distro. Valve? They decided its easier to just provide an unchaning set of libraries since they need to support existing games that got things wrong anyway and already have a distribution platform to distribute such a base system along with the games without bundling it into every single one.

A few links gathered from a quick google search as a primer:

http://stevehanov.ca/blog/?id=97

https://www.evanjones.ca/portable-linux-binaries.html

https://insanecoding.blogspot.com/2012/07/creating-portable-...

https://rpg.hamsterrepublic.com/ohrrpgce/Portable_GNU-Linux_...

https://github.com/wheybags/glibc_version_header

In other words: there are a lot of steps and a lot of gotchyas to doing this that you're glossing over. Linux userland libraries are generally designed with the intention that an army of third-party maintainers will integrate all of this desperately developed software together and place it in a repo. Naturally every distribution wants to do things a little differently too, and they have a habit of changing it up every couple years. When you try to step out of that mold things unsurprisingly become more difficult. Whereas Windows, Mac, Android, etc. have been designed since the beginning not to require that sort of thing and it is consequently a much, much more straightforward process.

I'm curious why, since you seem to believe the process is so straight-forward, you think it is that so few people distribute a simple binary? Why were Flatpak and AppImage invented?

> Binaries compiled against today's glibc can fail to run on a machine that hasn't been updated since last week because they rely on a new / different symbol.

Note, however, that it is a Glibc bug (modulo Drepper’s temper) if the reverse happens: Glibc symbol versioning ensures that binaries depending on an old Glibc (only) will run on a new one. So the proper way to build a maximally-compatible Linux executable would be to build a cross toolchain targeting an old Glibc and compile your code with it. Unfortunately, the build system is hell and old Glibcs doesn’t compile without backported patches, so while I did try to follow in the footsteps of a couple of people[1–4], I did not succeed.

Mass-rebuilds still happen with other ecosystems, though. GHC-compiled Haskell libraries are fine-grained and not ABI-stable across compiler versions, so my Arch box regularly gets hit with a deluge of teensy library updates, and Arch is currently undergoing a massive Python rebuild (blocking all other Python package updates) behind the scenes as well.

[1]: https://github.com/wheybags/glibc_version_header (hack but easy and will probably work most of the time)