toolchain resolution should take into account no-remote tags.

[cphang99]

Description of the problem / feature request:

This affects cross-platform builds (e.g. host is windows, remote-workers are linux) involving remote-execution that utilise platforms and toolchains.

If a test target is tagged as no-remote or no-remote-exec, toolchain resolution does not take this into account and determine that the execution constraints should be modified to be that of the host platform. If this is not done, a different toolchain can be selected that is incompatible and causes builds to fail.

In the case of cross-platform builds, a workaround is to manually set the execution constraints in the test target with exec_compatible_with to that of the host platform. Ideally however, this should be automatically detected during toolchain resolution.

What operating system are you running Bazel on?

macOS

What's the output of bazel info release?

0.29.1

[aragos]

This seems closely related to this design discussion regarding unifying strategies and execution platforms.

[katre]

@aragos, this sounds like something that should be handled by your latest project.

[katre]

This is now my project.

[katre]

Closing this in favor of the canonical tracking issue for execution platforms and strategies, #11432.