Failed to compile | Rust 1.43.0 | Ubuntu 20.04 - 64bit

[DeBarrosDaRapper]

error[E0658]: `while` is not allowed in a `const fn`
   --> /home/box/.cargo/registry/src/github.com-1ecc6299db9ec823/bs58-0.4.0/src/alphabet.rs:107:9
    |
107 | /         while i < encode.len() {
108 | |             if base[i] >= 128 {
109 | |                 return Err(Error::NonAsciiCharacter { index: i });
110 | |             }
...   |
120 | |             i += 1;
121 | |         }
    | |_________^
    |
    = note: see issue #52000 <https://github.com/rust-lang/rust/issues/52000> for more information

error[E0658]: `if` is not allowed in a `const fn`
   --> /home/box/.cargo/registry/src/github.com-1ecc6299db9ec823/bs58-0.4.0/src/alphabet.rs:108:13
    |
108 | /             if base[i] >= 128 {
109 | |                 return Err(Error::NonAsciiCharacter { index: i });
110 | |             }
    | |_____________^
    |
    = note: see issue #49146 <https://github.com/rust-lang/rust/issues/49146> for more information

error[E0658]: `if` is not allowed in a `const fn`
   --> /home/box/.cargo/registry/src/github.com-1ecc6299db9ec823/bs58-0.4.0/src/alphabet.rs:111:13
    |
111 | /             if decode[base[i] as usize] != 0xFF {
112 | |                 return Err(Error::DuplicateCharacter {
113 | |                     character: base[i] as char,
114 | |                     first: decode[base[i] as usize] as usize,
115 | |                     second: i,
116 | |                 });
117 | |             }
    | |_____________^
    |
    = note: see issue #49146 <https://github.com/rust-lang/rust/issues/49146> for more information

error[E0658]: `match` is not allowed in a `const fn`
   --> /home/box/.cargo/registry/src/github.com-1ecc6299db9ec823/bs58-0.4.0/src/alphabet.rs:156:12
    |
156 |           [][match result {
    |  ____________^
157 | |             Ok(alphabet) => return alphabet,
158 | |             Err(_) => 0,
159 | |         }]
    | |_________^
    |
    = note: see issue #49146 <https://github.com/rust-lang/rust/issues/49146> for more information

   Compiling void v1.0.2
error: aborting due to 4 previous errors

For more information about this error, try `rustc --explain E0658`.
error: could not compile `bs58`.

To learn more, run the command again with --verbose.
warning: build failed, waiting for other jobs to finish...
error: build failed

[DeBarrosDaRapper]

This is what the rustc --explain E0658 outputs:

An unstable feature was used.

Erroneous code example:

#[repr(u128)] // error: use of unstable library feature 'repr128'
enum Foo {
    Bar(u64),
}

If you're using a stable or a beta version of rustc, you won't be able to use
any unstable features. In order to do so, please switch to a nightly version of
rustc (by using rustup).

If you're using a nightly version of rustc, just add the corresponding feature
to be able to use it:

#![feature(repr128)]

#[repr(u128)] // ok!
enum Foo {

[cryptoquick]

Continuing from our conversation on Discord:

Try compiling with the nightly toolchain, install it using rustup (rustup toolchain install nightly , if i recall correctly), then use cargo +nightly run

If that resolves it, we'll just move towards defaulting to a nightly install. That'll help for frontend development, anyway.

[DeBarrosDaRapper]

``Sweet, installed rustup. Thank you!
However, I'm still experiencing compiling issues - I'm going to assert the issue is on my local machine.
Even after running the --classic, issue persists on my version of Ubuntu 20.04 LTS

sudo snap install rustup
error: This revision of snap "rustup" was published using classic confinement
and thus may perform arbitrary system changes outside of the security
sandbox that snaps are usually confined to, which may put your system at
risk.

   If you understand and want to proceed repeat the command including
   --classic

Closing issue.``

[cryptoquick]

@DeBarrosDaRapper to install rust and rustup, I would recommend uninstalling anything else you've installed (including any rust and rustup packages) and then following the instructions here:
https://rustup.rs/