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Re: [PATCH] Update sparc ULPs.
- From: "Joseph S. Myers" <joseph at codesourcery dot com>
- To: David Miller <davem at davemloft dot net>
- Cc: <libc-alpha at sourceware dot org>
- Date: Wed, 8 Aug 2012 20:00:10 +0000
- Subject: Re: [PATCH] Update sparc ULPs.
- References: <20120727.212345.607263830049997175.davem@davemloft.net><Pine.LNX.4.64.1207281722180.8879@digraph.polyomino.org.uk><20120807.205232.585358698230985397.davem@davemloft.net>
On Tue, 7 Aug 2012, David Miller wrote:
> The first new failure is in clog10l() and is definitely introduced by
> changes made in commit da865e95bcf9a5365de78fa6b5c681aca0a1bb46.
>
> It's for this libm-test.inc test:
>
> TEST_c_c (clog10, 0x1p-8189L, 1.0L, 1.168114274114528946314738738025008370069e-4931L, 6.821881769209206737428918127156778851051e-1L);
>
> This generates an underflow exception on sparc for long double.
>
> GLIBC before the commit does not generate the underflow exception.
That does look like a previously unknown bug. That exception doesn't
appear for x86 (with the same long double range but lower precision) ...
it could perhaps be a problem in the ldbl-128 log1pl. Does log1pl
(0x1p-16378L) (with of course -fno-builtin or use of volatile variables to
prevent compile-time computation) generate a spurious underflow exception?
--
Joseph S. Myers
joseph@codesourcery.com