cargo install gluon_repl fails to compile

[rowanfr]

When I try to run cargo install gluon_repl it fails to install due to:

error[E0308]: mismatched types
    --> ~/.cargo/registry/src/index.crates.io-6f17d22bba15001f/gluon_base-0.18.0/src/types/mod.rs:1042:24
     |
1042 | const _: [(); 8 * 6] = [(); std::mem::size_of::<Type<Symbol, ArcType>>()];
     |               -----    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected an array with a fixed size of 48 elements, found one with 40 elements
     |               |
     |               help: consider specifying the actual array length: `40`

   Compiling rand_core v0.6.4
   Compiling num_cpus v1.16.0
For more information about this error, try `rustc --explain E0308`.
error: could not compile `gluon_base` (lib) due to previous error
warning: build failed, waiting for other jobs to finish...
error: failed to compile `gluon_repl v0.18.0`, intermediate artifacts can be found at `/tmp/cargo-installSWuQke`

I've removed the other package compilation messages to focus on the error message

[Marwes]

Closed by #959 . Thanks!