Re: Exceeding limits during arithmetic

Mike Aubury wrote:

Is there any standard (or even non-standard) way to detect limit
overflow in arithmetic in C ?

eg.
/* assuming 4 byte ints.. */
int a=2147483647;
int b=2147483647;
int c;

c=a*b;

if (INT_MAX / b < a) overflow();
else c = a * b;

and #include <limits.h>. Diddle to handle -ve input values.

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