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unsafe block

A block of code where you take on proving some memory rules yourself.

An unsafe block permits five extra operations (dereferencing raw pointers, calling unsafe functions, implementing unsafe traits, accessing mutable statics and union fields); all other checks, including borrow checking, still apply.

Examples

  • chips.get_unchecked(1) outside an unsafe block fails with E0133; inside unsafe { chips.get_unchecked(1) } it compiles and the bounds proof is yours.

See also

raw pointer safety contract undefined behavior soundness
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