E0044: Integer Literal Out of Range

An integer literal does not fit in the type it was resolved to.

Example

fn main() {
    let x: i8 = 300;  // Error: integer literal `300` does not fit in type `i8`
}

fn main() {
    let y: u8 = -1;  // Error: integer literal `-1` does not fit in type `u8`
}

How to fix

Either use a literal value that fits within the target type's range, or use a wider type:

fn main() {
    let x: i8 = 100;   // OK: 100 fits in i8 (-128..127)
    let y: i16 = 300;   // OK: 300 fits in i16 (-32768..32767)
    let z: u8 = 255;    // OK: 255 fits in u8 (0..255)
}

Integer type ranges

Type	Min	Max
i8	-128	127
i16	-32768	32767
i32	-2147483648	2147483647
i64	-9223372036854775808	9223372036854775807
u8	0	255
u16	0	65535
u32	0	4294967295
u64	0	18446744073709551615