Adjusting help message

[murchu27]

On stable, running with --help|-h shows information about file-lines which is a nightly-only option (#4798). This commit removes all mention of file-lines from the help message on stable.

There is room for improvement here; perhaps a new struct called, e.g., StableOptions could be added to complement the existing GetOptsOptions struct. StableOptions could have a field for each field in GetOptsOptions, with each field's value being a bool that specifies whether or not the option exists on stable. Or is this adding too much complexity?

[murchu27]

Can I get a bit of help with this? I'm not sure what's wrong with the failing checks. All of them (except the Windows ones) seem to have some error like the below when compiling

error[E0658]: unsizing casts to types besides slices are not allowed in const fn
   --> /home/runner/.cargo/registry/src/github.com-1ecc6299db9ec823/rustc-ap-rustc_ast-712.0.0/src/ptr.rs:136:37
    |
136 |                 std::mem::transmute(NonNull::<[T; 0]>::dangling() as NonNull<[T]>)
    |                                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: see issue #64992 <https://github.com/rust-lang/rust/issues/64992> for more information
    = help: add `#![feature(const_fn_unsize)]` to the crate attributes to enable

error: aborting due to previous error

What can I do about this?

[calebcartwright]

What can I do about this?

So sorry @murchu27, this slipped past me in my notification inbox somehow. You should be able to rebase on the master branch of this repository to resolve (just be sure to reference the upstream or whatever remote name you used for this, since we've subsequently changed the master branch to contain the same 1.x version of the code you were working with, refs #4801)

[murchu27]

Thanks @calebcartwright. I'll rebase and raise a new PR. Will I merge into the master branch here, or stick with rustfmt-1.4.37?