Upgrade Rust base (9th June) (fb7cca33f)

[dylanmckay]

I've rebased the #137 branch one more time to bring it two months forward - from April to June.

[dylanmckay]

I can successfully compile blink to ELF in release mode with this branch.

[shepmaster]

blink to ELF in release mode

As far as I'm concerned, that's our current "golden master", so I'd be OK "merging" this as our master branch once we've made sure it compiles on at least a second machine (is the current CI enough for that?)

[Rahix]

@shepmaster, I can test compile my HAL crates with it tomorrow if you want

[dylanmckay]

@shepmaster the CI run successfully ran make && make install.

[Rahix]

Everything seems to work as it should! 👍

[dylanmckay]

I have force pushed avr-support to 9a1785d and master to fb7cca3.

[shepmaster]

FWIW, I can compile my AVR-GCC-free blink example just fine as well!

[peacememories]

hmm, i updated my avr-rust installation, and now my projects fail to build core with the following error message:

   Compiling compiler_builtins v0.1.16
     Running `rustc --crate-name build_script_build /Users/user/.cargo/registry/src/github.com-1ecc6299db9ec823/compiler_builtins-0.1.16/build.rs --color always --crate-type bin --emit=dep-info,link -C opt-level=3 --cfg 'feature="compiler-builtins"' --cfg 'feature="default"' --cfg 'feature="mem"' -C metadata=622f0871509f1a77 -C extra-filename=-622f0871509f1a77 --out-dir /var/folders/9b/sq7l7grn1_q_bm74x5x67z8r0000gn/T/xargo.PukdOc8v32h1/target/release/build/compiler_builtins-622f0871509f1a77 -L dependency=/var/folders/9b/sq7l7grn1_q_bm74x5x67z8r0000gn/T/xargo.PukdOc8v32h1/target/release/deps --cap-lints allow`
error[E0463]: can't find crate for `std`

error: aborting due to previous error

For more information about this error, try `rustc --explain E0463`.
error: Could not compile `compiler_builtins`.

Any idea what might have gone wrong?

[shepmaster]

can't find crate for std

There certainly isn't a std crate for AVR: no filesystem, no threads, etc. I don't know how your code could have been compiling before.

Unless build scripts use the host system's libstd, in which case it seems like your build might not be complete. Did you try deleting the build artifacts and doing a clean build? Are you following the instructions in the README?

[peacememories]

Of course the project itself isn't using std (it's for avr after all). It seems the cross compilation of libcore is using it somewhere. When I updated I ultimately cloned the whole repository again and built it. Maybe something's stale in ~/.xargo ~/.cargo or ~/.rustup? I don't know.

[Rahix]

I suggest deleting .xargo and trying again ... At least I had to do that to get the new version working, but the error message was a different one ...

[peacememories]

Deleted .xargo and the whole compiler and built it again, the problem seems to persist.

[Rahix]

@peacememories: You are probably using rustup, right? Which directory did you link the toolchain to, using rustup toolchain link <...>?

[peacememories]

lrwxr-xr-x 69 gabriel 13 Jun 16:14 avr-toolchain -> /Users/user/Library/Rust/avr-rust/build/x86_64-apple-darwin/stage1

[Rahix]

Try linking against stage2 instead. If that doesn't work, set an install prefix in config.toml, run make install (or x.py install iirc) and then link against the directory you installed to

[peacememories]

linking against stage2 works. huh. I could've sworn the docs say you should link against stage1?

[peacememories]

Thanks anyway, now I can continue working :)

[shepmaster]

huh. I would have sworn that I used stage1 (and I likely wrote the README), but I do have it set to stage2 as well:

/Users/shep/.rustup/toolchains/avr -> /Users/shep/Projects/avr-rust/build/build/x86_64-apple-darwin/stage2

I'll change that in the readme.

[shepmaster]

run make install

FWIW, I've never installed Rust using this mechanism in the 4 years I've been using it; I always use my local builds right out of the build directory. I kind of regret that we have it in our README at all.

[Rahix]

Darn, I was just about to send you a pull-request with updated instructions :D