`sgx_align_struct_attribute` compile error

[EmisonLu]

rust-sdk version: v1.1.4
rustc version: rustc 1.57.0-nightly (51e514c0f 2021-09-12)
When I use cargo b in the folder sgx_align_struct_attribute, the following error is reported:

error[E0658]: use of unstable library feature 'proc_macro_is_available'
  --> /home/emison/.cargo/registry/src/mirrors.tuna.tsinghua.edu.cn-df7c3c540f42cdbd/proc-macro2-1.0.33/src/detection.rs:28:21
   |
28 |     let available = proc_macro::is_available();
   |                     ^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = note: see issue #71436 <https://github.com/rust-lang/rust/issues/71436> for more information
   = help: add `#![feature(proc_macro_is_available)]` to the crate attributes to enable

[volcano0dr]

Thank you for reporting this issue.
I am aware of this issue and I will fix it by upgrading the rust toolchain to nightly-2021-11-01.
rust-lang/rust#71436

[volcano0dr]

@EmisonLu I have upgraded rust-toolchain to nightly-2021-11-01.

[EmisonLu]

Many thanks!