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    SubjectRe: 2.4.0-test10-pre6: Use of abs()
    Richard Henderson wrote:
    >
    > On Wed, Nov 01, 2000 at 09:46:19AM -0500, tytso@mit.edu wrote:
    > > What versions of gcc produce the built-in functions?
    >
    > 2.95 and previous. In 2.96 somewhere we fixed a bug that
    > automatically prototypes these builtin functions for you;
    > ie with current code you get an undeclared function warning.
    >
    > > And does it do so for *all* platforms? (i.e., PPC, Alpha,
    > > IA64, etc., etc., etc.)
    >
    > Yes. The thing about abs, though, is that it's "int abs(int)"
    > which does naughty things with longs on 64-bit targets. You're
    > much better off writing (x < 0 ? -x : x) directly.

    Thank's for answering it... I was already looking up the GCC source for
    an exact answer ;-). However what's the difference in respect of
    optimization between unrolling the abs function by hand and
    relying on the built in?
    -
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