Make it possible for source files to be unresolved symlinks

[lberki]

Description of the feature request:

Generated files can now be unresolved symlinks, in which case Bazel uses the value returned by readlink() and not by read() to determine whether it has changed; they can even be dangling symlinks that way.

For symmetry, it would be nice if source files also had this ability.

What underlying problem are you trying to solve with this feature?

No response

Which operating system are you running Bazel on?

No response

What is the output of bazel info release?

No response

If bazel info release returns development version or (@non-git), tell us how you built Bazel.

No response

What's the output of git remote get-url origin; git rev-parse master; git rev-parse HEAD ?

No response

Have you found anything relevant by searching the web?

No response

Any other information, logs, or outputs that you want to share?

No response

[haxorz]

Generated files can now be unresolved symlinks

This is referring to the --experimental_allow_unresolved_symlinks flag discussed in #10298 and especially the recent flip of the default value of that flag in 27cfc83, right?

[lberki]

Yep.

[larsrc-google]

Do you have an actual use case for this? Symmetry sounds nice, but not adding code that doesn't get used sounds even nicer.

[lberki]

My understanding is that the Chrome OS SDK contains file system trees and those have symlinks that are not dangling when installed, but are dangling on the system where the build happens.

I'll add to you to the pertinent thread.

[github-actions]

Thank you for contributing to the Bazel repository! This issue has been marked as stale since it has not had any activity in the last 1+ years. It will be closed in the next 90 days unless any other activity occurs. If you think this issue is still relevant and should stay open, please post any comment here and the issue will no longer be marked as stale.