Get all tests passing with --incompatible_disable_legacy_cc_provider for Bazel 0.25.0

[oquenchil]

It seems that rules_rust will start breaking with the next Bazel release 0.25 because of an incompatible change (bazelbuild/bazel#7036)

ERROR: /home/bazel/.cache/bazel/_bazel_bazel/c922ef9e5f39c5bf7c8601dab4c6fea8/external/examples/ffi/rust_calling_c/BUILD:29:1: in rust_library rule @examples//ffi/rust_calling_c:matrix_dynamically_linked:
--
  | Traceback (most recent call last):
  | File "/home/bazel/.cache/bazel/_bazel_bazel/c922ef9e5f39c5bf7c8601dab4c6fea8/external/examples/ffi/rust_calling_c/BUILD", line 29
  | rust_library(name = 'matrix_dynamically_linked')
  | File "/home/bazel/.cache/bazel/_bazel_bazel/c922ef9e5f39c5bf7c8601dab4c6fea8/external/io_bazel_rules_rust/rust/private/rust.bzl", line 85, in _rust_library_impl
  | rustc_compile_action(ctx = ctx, toolchain = toolchain, cr...)), ...)
  | File "/home/bazel/.cache/bazel/_bazel_bazel/c922ef9e5f39c5bf7c8601dab4c6fea8/external/io_bazel_rules_rust/rust/private/rustc.bzl", line 180, in rustc_compile_action
  | collect_deps(crate_info.deps, toolchain)
  | File "/home/bazel/.cache/bazel/_bazel_bazel/c922ef9e5f39c5bf7c8601dab4c6fea8/external/io_bazel_rules_rust/rust/private/rustc.bzl", line 116, in collect_deps
  | fail(("rust targets can only depend o...)), ...")
  | attribute deps: rust targets can only depend on rust_library, rust_*_library or cc_library targets.<target @examples//ffi/rust_calling_c/c:native_matrix_so>

The code is using the old legacy provider cc, it can be replaced with CcInfo to get the same functionality as described here.

[mfarrugi]

Same as #190.

Looks like CI is on bazel 0.22 right now, which suggests it's still to early to bump rules_rust minimum bazel version to 0.22.

[oquenchil]

Hey Marco, this is still showing up as broken in our CI. If I remember correctly 0.23 already had the API available, perhaps even as early as 0.22. Is anything blocking this that we can help with?

[mfarrugi]

#190 mentions the version constraints.

Which CI is broken? I don't want to do this upgrade right now because we are on v20 internally, and v24 is not released yet (the straightforward update bumps up our minimum version to v22, which has only been out for a month).

We could support both APIs if you need this change right now, and I would be happy to take a PR for it.

[oquenchil]

rules_rust is in our list of downstream projects (in Bazel). We just wanted to let you know about this so that the breaking change doesn't catch you by surprise. If I understand correctly you will upgrade to v24 once it's released and then fix the incompatible change?

[mfarrugi]

Yes, I had planned to upgrade once v24 was released (so then we would have support 22, 23, and 24).

[hlopko]

Hello, just a friendly notification that 0.24 was released yesterday :)

[meteorcloudy]

@mfarrugi Thanks for the fix!