7 Expressions [expr]

7.3 Standard conversions [conv]

7.3.8 Integral conversions [conv.integral]

1
#
A prvalue of an integer type can be converted to a prvalue of another integer type.
A prvalue of an unscoped enumeration type can be converted to a prvalue of an integer type.
2
#
If the destination type is bool, see [conv.bool].
If the source type is bool, the value false is converted to zero and the value true is converted to one.
3
#
Otherwise, the result is the unique value of the destination type that is congruent to the source integer modulo , where N is the width of the destination type.
4
#
The conversions allowed as integral promotions are excluded from the set of integral conversions.