[PATCH v2] Avoid undefined behaviour in ibm128 implementation of llroundl

[Michael Hudson-Doyle]

On Mon, 22 Aug 2022, 20:34 Andreas Schwab, <schwab@suse.de> wrote:

> On Aug 22 2022, Michael Hudson-Doyle via Libc-alpha wrote:
>
> > @@ -69,7 +70,7 @@ __llroundl (long double x)
> >        res = hi + lo;
>
> The overflow happens here.  Changing the type of the LHS does not change
> that.
>

IIRC it was one of the "res += 1"s lower down in the test case that was
failing for me. But maybe a more thorough rewrite of this function is
called for (if people still care about ibm128 I guess).

Cheers,
mwh

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> Andreas Schwab, SUSE Labs, schwab@suse.de
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