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Re: Updating NEWS for 2.26
On Wed, 5 Jul 2017, Joseph Myers wrote:
> I think the appropriate length depends on the size of the feature.
> Typically we'd expect to list the new interfaces (which may sometimes be
> quite a long list, e.g. the TS 18661-1 functions in 2.25), but in this
> case a briefer description in terms of how they relate to existing
> features for other types should suffice.
Specifically, the following seems like a reasonable length for this
feature to me.
* On ia64, powerpc64le, x86-32, and x86-64, the math library now implements
128-bit floating point as defined by ISO/IEC/IEEE 60559:2011 (IEEE
754-2008) and ISO/IEC TS 18661-3:2015. Contributed by Paul E. Murphy,
Gabriel F. T. Gomes, Tulio Magno Quites Machado Filho, and Joseph Myers.
To compile programs that use this feature, the compiler must support
128-bit floating point with the type name _Float128 (as defined by TS
18661-3) or __float128 (the nonstandard name used by GCC for C++, and for
C prior to version 7). _GNU_SOURCE or __STDC_WANT_IEC_60559_TYPES_EXT__
must be defined to make the new interfaces visible.
The new functions and macros correspond to those present for other
floating-point types (except for a few obsolescent interfaces not
supported for the new type), with F128 or f128 suffixes; for example,
strtof128, HUGE_VAL_F128 and cosf128. Following TS 18661-3, there are no
printf or scanf formats for the new type; the strfromf128 and strtof128
interfaces should be used instead.
--
Joseph S. Myers
joseph@codesourcery.com