Doesn't build with current nightly

[kyrias]

error[E0599]: no method named `is_xid_start` found for type `char` in the current scope
   --> /home/kyrias/.cargo/registry/src/gh.neting.cc-1ecc6299db9ec823/runtime-fmt-0.3.0/src/fmt_macros.rs:422:34
    |
422 |             Some(&(pos, c)) if c.is_xid_start() => {
    |                                  ^^^^^^^^^^^^ method not found in `char`

error[E0599]: no method named `is_xid_continue` found for type `char` in the current scope
   --> /home/kyrias/.cargo/registry/src/gh.neting.cc-1ecc6299db9ec823/runtime-fmt-0.3.0/src/fmt_macros.rs:431:18
    |
431 |             if c.is_xid_continue() {
    |                  ^^^^^^^^^^^^^^^ method not found in `char`

It seems to have broken due to rust-lang/rust@27b703d. Does anyone know what the last working nightly was?

[Arkweid]

@kyrias 1.38.0-nightly (4b65a86eb 2019-07-15) works fine

[s-a-y]

I had the same issue (8 build errors)
With 1.38.0-nightly these errors seem to go away, but 6 others are still there.

error[E0106]: missing lifetime specifier
   --> /Users/dev/.cargo/registry/src/gh.neting.cc-1ecc6299db9ec823/futures-io-preview-0.3.0-alpha.19/src/lib.rs:292:28
    |
292 |             -> Poll<Result<&[u8]>>;
    |                            ^ expected lifetime parameter
    |
    = help: this function's return type contains a borrowed value, but the signature does not say which one of argument 2's 2 lifetimes it is borrowed from

error[E0106]: missing lifetime specifier
   --> /Users/dev/.cargo/registry/src/gh.neting.cc-1ecc6299db9ec823/futures-io-preview-0.3.0-alpha.19/src/lib.rs:559:32
    |
559 |                 -> Poll<Result<&[u8]>>
    |                                ^ expected lifetime parameter
...
571 |         deref_async_buf_read!();
    |         ------------------------ in this macro invocation
    |
    = help: this function's return type contains a borrowed value, but the signature does not say which one of `cx`'s 2 lifetimes it is borrowed from

error[E0106]: missing lifetime specifier
   --> /Users/dev/.cargo/registry/src/gh.neting.cc-1ecc6299db9ec823/futures-io-preview-0.3.0-alpha.19/src/lib.rs:559:32
    |
559 |                 -> Poll<Result<&[u8]>>
    |                                ^ expected lifetime parameter
...
575 |         deref_async_buf_read!();
    |         ------------------------ in this macro invocation
    |
    = help: this function's return type contains a borrowed value, but the signature does not say which one of `cx`'s 2 lifetimes it is borrowed from

error[E0106]: missing lifetime specifier
   --> /Users/dev/.cargo/registry/src/gh.neting.cc-1ecc6299db9ec823/futures-io-preview-0.3.0-alpha.19/src/lib.rs:584:28
    |
584 |             -> Poll<Result<&[u8]>>
    |                            ^ expected lifetime parameter
    |
    = help: this function's return type contains a borrowed value, but the signature does not say which one of `cx`'s 2 lifetimes it is borrowed from

error[E0106]: missing lifetime specifier
   --> /Users/dev/.cargo/registry/src/gh.neting.cc-1ecc6299db9ec823/futures-io-preview-0.3.0-alpha.19/src/lib.rs:597:32
    |
597 |                 -> Poll<Result<&[u8]>>
    |                                ^ expected lifetime parameter
...
609 |         delegate_async_buf_read_to_stdio!();
    |         ------------------------------------ in this macro invocation
    |
    = help: this function's return type contains a borrowed value, but the signature does not say which one of argument 2's 2 lifetimes it is borrowed from

error[E0106]: missing lifetime specifier
   --> /Users/dev/.cargo/registry/src/gh.neting.cc-1ecc6299db9ec823/futures-io-preview-0.3.0-alpha.19/src/lib.rs:597:32
    |
597 |                 -> Poll<Result<&[u8]>>
    |                                ^ expected lifetime parameter
...
613 |         delegate_async_buf_read_to_stdio!();
    |         ------------------------------------ in this macro invocation
    |
    = help: this function's return type contains a borrowed value, but the signature does not say which one of argument 2's 2 lifetimes it is borrowed from

error: aborting due to 6 previous errors

Any ideas what can be done? I'm pretty new to rust