# Extra Clang Tools 4 documentation

## clang-tidy - misc-redundant-expression

# misc-redundant-expression

Detect redundant expressions which are typically errors due to copy-paste.

Depending on the operator expressions may be

- redundant,
- always be `true`,
- always be `false`,
- always be a constant (zero or one).

Example:

    ((x+1) | (x+1))             // (x+1) is redundant
    (p->x == p->x)              // always true
    (p->x < p->x)               // always false
    (speed - speed + 1 == 12)   // speed - speed is always zero