How can I ensure that integer arithmetic doesnt overflow?

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The usual approach is to test the operands against the limits in the header file <limits.h> before doing the operation. For example, here is a ``careful'' addition function:

int
chkadd(int a, int b)
{
if(INT_MAX - b < a) {
fputs("int overflow\n", stderr);
return INT_MAX;
}
return a + b;
}

2015-03-04, 1421👍, 0💬

How can I ensure that integer arithmetic doesnt overflow?
How can I ensure that integer arithmetic doesnt overflow? The usual approach is to test the operands against the limits in the header file <limits.h> before doing the operation. For example, here is a ``careful'' addition function: int chkadd(int a, int b) { if(INT_MAX - b < a) { fputs... 2015-03-04, 1422👍, 0💬

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Why isnt any of this standardized in C? Any real program has to do some of these things.
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But I cant use all these nonstandard, system-dependent functions, because my program has to be ANSI compatible!
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I'm trying to compile this program, but the compiler is complaining that ``union REGS'' is undefined, and the linker is complaining that int86 is undefined. Those have to do with MS-DOS interrupt programming. They don't exist on other systems. 2015-03-02, 1379👍, 0💬

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