Compiling Errors When Using on Solana Contracts

[mdulin2]

I've tried running the lints on the built-in Solana test contracts and on personal projects with the current toolchains that are set up. However, I keep getting errors in solana-program:

    Checking solana-program v1.18.26
error[E0658]: use of unstable library feature 'offset_of'
   --> /Users/strikeout/.cargo/registry/src/index.crates.io-6f17d22bba15001f/solana-program-1.18.26/src/program.rs:441:20
    |
441 |         assert_eq!(offset_of!(StableInstruction, program_id), 48);

When I tried to change the toolchain to the nightly setup, I also got build errors within clippy.

Am I missing something here? I am happy to admit fault on compiling the code but would appreciate some guidance on running the built-in Solana test contracts for the specific lints.

[mdulin2]

This project is awesome though :) I'm looking to build some stuff on top of this.