I've been using no-panic crate/hack to get higher assurances about code behavior.
Here is the command:

RUSTFLAGS="-Cllvm-args=--inline-threshold=5000 -C embed-bitcode -C lto -Z dylib-lto -C target-cpu=native" cargo build --all-targets --release --features no-panic

It works pretty well for crates individually (by individual I mean its tests and benchmarks), but I'm having issues with the same crate that was built successfully if it is used as a dependency in another crate (by that I mean another crate's tests and benchmarks).

All of a sudden, compiler is unable to eliminate some parts of the code and no longer able to prove that panics can't happen, which is concerning for performance reasons too.

--inline-threshold=5000 is already quite high and getting it higher and higher isn't really practical.

I know this is not a very popular thing to do in Rust ecosystem, at least not yet, but I find it quite fascinating.

Any pointers as to why that might be the case in case I'm missing something?

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