> Aztec.nr API reference, v6.0.0 (mainnet and testnet). Index: https://docs.aztec.network/aztec-nr-api/v6.0.0/llms.txt

# Function black_box

Module: `std::hint`

```rust
pub fn black_box<T>(value: T) -> T
```

An identity function that *hints* to the compiler to be maximally pessimistic about what `black_box` could do.

This can be used to block the SSA optimization passes being applied to a value, which should help to prevent test programs from being optimized down to nothing and have them resemble runtime code more closely.