Compiling on Windows is currently broken

[clauswilke]

Compiling with Windows currently errors out:

error: linking with `x86_64-w64-mingw32-gcc` failed: exit code: 1
...
  = note: C:/rtools40/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/8.3.0/../../../../x86_64-w64-mingw32/bin/ld.exe: cannot find -lgcc_eh
          collect2.exe: error: ld returned 1 exit status
          

error: aborting due to previous error

error: could not compile `getrandom`

This may be related to the release of rustc 1.48.0, see here: https://users.rust-lang.org/t/announcing-rust-1-48-0/51677/6

[clauswilke]

Here is an old issue that is possibly related: rust-lang/rust#41607

[clauswilke]

@yutannihilation Do you happen to have any idea how to approach/fix this build problem on Windows? I suspect it'll eventually hit the extendr project as well.

[yutannihilation]

No idea. Curious... Do you think this is an issue specific to getrandom crate?

error: could not compile `getrandom`

[clauswilke]

No, I don't think so:
rust-lang/rust#41607 (comment)

[yutannihilation]

Okay, it seems time to boot my old Windows again...

[clauswilke]

If you could look into it, that would be great! I saw a post somewhere saying it was something about a path issue (it uses x86_64-w64-mingw32/bin/ld.exe instead of the linker shipped with Rust), but I can't find that post anymore and I don't have Windows to test.

[yutannihilation]

Before I jump into the hell of Windows Updates, I tried Windows runner on GitHub Actions CI, and it seems there's no compilation error happens. Curious...

https://github.com/yutannihilation/sinab/runs/1480737543

diff: master...yutannihilation:master

[clauswilke]

That's good to know. Maybe it is a path issue after all. Could you turn this into a PR? And what does override: true do?

[yutannihilation]

Sure, I'll create a PR.

The document says override is to

Set installed toolchain as an override for the current directory
https://github.com/actions-rs/toolchain#inputs

But, I didn't know about the details, I just copied this from the instruction on hellorust, which was recently added. I guess this is for ensuring the runner uses the intended toolchain even when there's already another Rust toolchain installed, so this probably doesn't matter in usual cases.

[yutannihilation]

Confirmed it works without override.

https://github.com/yutannihilation/sinab/runs/1483598627

[clauswilke]

Closing this as it does work on GH Actions. Probably something is not quite right in the Appveyor setup, but there's nothing fundamental that is broken with the code.