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Re: [PING] [PATCH] PowerPC libm-test.inc expl(1000.0L) resultexceeds __LDBL_MAX__ for IBM Long Double 128.
- From: "Ryan S. Arnold" <rsa at us dot ibm dot com>
- To: Ulrich Drepper <drepper at redhat dot com>
- Cc: libc-alpha at sources dot redhat dot com, Roland McGrath <roland at redhat dot com>
- Date: Thu, 22 May 2008 14:44:25 -0500
- Subject: Re: [PING] [PATCH] PowerPC libm-test.inc expl(1000.0L) resultexceeds __LDBL_MAX__ for IBM Long Double 128.
- References: <1203538706.11373.40.camel@localhost> <1211470005.16932.8.camel@localhost> <4835BCF1.3050806@redhat.com>
- Reply-to: rsa at us dot ibm dot com
On Thu, 2008-05-22 at 11:35 -0700, Ulrich Drepper wrote:
> I don't understand this. This exponent for the format is 15 bits in (14
> bits but sign). That's an exponent of 16384. Where is the problem?
Hi Ulrich,
PowerPC uses the IBM Long Double 128 format which is double double, not
IEEE128. So it has an 11-bit exponent and effective 106 bit mantissa.
Ryan S. Arnold
IBM Linux Technology Center
Linux Toolchain Development