Re: MSEC_TO_JIFFIES is messed up...

From: Andreas Schwab
Date: Wed May 12 2004 - 16:57:33 EST


"J. Bruce Fields" <bfields@xxxxxxxxxxxx> writes:

> If gcc really optimizes that to just the identity function, then surely
> that's a gcc bug? Multiplication is left-associative, so i * 1000 /
> 1000 = (i * 1000) / 1000, but (i * 1000) should be zero for any i
> divisible by i^(sizeof(int) - 12).

Signed integer overflow is undefined in C, so the compiler is allowed to
assume it does not happen.

Andreas.

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Andreas Schwab, SuSE Labs, schwab@xxxxxxx
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