Failed to Build: error[E0658]

[*=0=1=4=*]

TL;DR

To fix this error, run rustup update to get the latest Rust toolchains installed.

Details

I actually solved this problem and just wanted to document it for anyone in the future.

Original Error

cargo install --git https://github.com/dsprenkels/sss-cli --branch v0.1

Updating git repository https://github.com/dsprenkels/sss-cli
Installing shamirsecretsharing-cli v0.1.1 (https://github.com/dsprenkels/sss-cli?branch=v0.1#d327af9d)
Updating crates.io index
Compiling libc v0.2.121
Compiling cfg-if v1.0.0
Compiling getrandom v0.1.16
Compiling memchr v2.4.1
Compiling cc v1.0.73
Compiling log v0.4.14
Compiling unicode-width v0.1.9
Compiling ppv-lite86 v0.2.16
Compiling regex-syntax v0.6.25
Compiling quick-error v1.2.3
Compiling ansi_term v0.12.1
Compiling bitflags v1.3.2
Compiling strsim v0.8.0
Compiling termcolor v1.1.3
Compiling humantime v1.3.0
Compiling textwrap v0.11.0
Compiling aho-corasick v0.7.18
Compiling atty v0.2.14
Compiling clap v2.34.0
Compiling rand_core v0.5.1
Compiling rand_chacha v0.2.2
error[E0658]: if is not allowed in a const fn
--> ~/.cargo/registry/src/github.com-1ecc6299db9ec823/clap-2.34.0/src/app/settings.rs:7:1
|
7 | / bitflags! {
8 | | struct Flags: u64 {
9 | | const SC_NEGATE_REQS = 1;
10 | | const SC_REQUIRED = 1 << 1;
... |
51 | | }
52 | | }
| |_^
|
= note: see issue #49146 rust-lang/rust#49146 for more information
= note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)

error[E0658]: if is not allowed in a const fn
--> ~/.cargo/registry/src/github.com-1ecc6299db9ec823/clap-2.34.0/src/args/settings.rs:6:1
|
6 | / bitflags! {
7 | | struct Flags: u32 {
8 | | const REQUIRED = 1;
9 | | const MULTIPLE = 1 << 1;
... |
28 | | }
29 | | }
| |_^
|
= note: see issue #49146 rust-lang/rust#49146 for more information
= note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)

Compiling rand v0.7.3
Compiling regex v1.5.5
error: aborting due to 2 previous errors

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

To learn more, run the command again with --verbose.
warning: build failed, waiting for other jobs to finish...
error: failed to compile `shamirsecretsharing-cli v0.1.1

Before Updating

This is the version that caused the error.

rustup show

Default host: x86_64-unknown-linux-gnu
rustup home: ~/.rustup

installed toolchains

---

stable-x86_64-unknown-linux-gnu (default)
nightly-2020-10-25-x86_64-unknown-linux-gnu
nightly-2021-01-01-x86_64-unknown-linux-gnu
nightly-2021-05-18-x86_64-unknown-linux-gnu
nightly-2021-07-06-x86_64-unknown-linux-gnu

active toolchain

---

stable-x86_64-unknown-linux-gnu (default)
rustc 1.43.1 (8d69840ab 2020-05-04)

After Updating

I was able to install with this version.

rustup show

Default host: x86_64-unknown-linux-gnu
rustup home: ~/.rustup

installed toolchains

---

stable-x86_64-unknown-linux-gnu (default)
nightly-2020-10-25-x86_64-unknown-linux-gnu
nightly-2021-01-01-x86_64-unknown-linux-gnu
nightly-2021-05-18-x86_64-unknown-linux-gnu
nightly-2021-07-06-x86_64-unknown-linux-gnu

active toolchain

---

stable-x86_64-unknown-linux-gnu (default)
rustc 1.59.0 (9d1b2106e 2022-02-23)