checking for overflow in C

[Tim McDaniel]

You can always do pre-checks, given <limits.h> or something like it:
        unsigned int a, b, c;
        ...
        assert(b == 0 || a <= UINT_MAX / b);
        c = a * b;
Similarly for other types and operations.  For unsigned adds, you can
do a post-check:
        c = a + b
overflowed if and only if c <= a or c <= b.

--

             Tim, the Bizarre and Oddly-Dressed Enchanter

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