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In modwrap semantics (also called _modulo_ arithmetic), integer values "wrap round."  That is, adding one to {{MAX}} produces {{MIN}}.  This is the defined behavior for unsigned integers in the C Standard \[[ISO/IEC 9899:1999|AA. Bibliography#ISO/IEC 9899-1999]\], Section 6.2.5, "Types," paragraph 9,. andThis is frequently the behavior of signed integers, as well.  However, it is more sensible in many applications to use saturation semantics instead of modwrap semantics.  For example, in the computation of a size (using unsigned integers), it is often better for the size to stay at the maximum value in the event of overflow rather than suddenly becoming a very small value.

Now, if the user types {{a < b}}, there is often an implicit subtraction happening.  On a machine without condition codes, the compiler may simply issue a subtract instruction and check whether the result is negative.  This is allowed because the compiler is allowed to assume there is no overflow.  If all explicitly user-generated values are kept in the range {{\[INT_MIN/2, INT_MAX/2\]}}, then comparisons will always work even if the compiler performs this optimization on such hardware.