long double format on I!64

[Bo Thorsen]

On Thursday 29 August 2002 00:02, Gabriel Dos Reis wrote:
> Hi,
>
>   I've been reviewing the fundamental data types format as
> communicated to V3 sources. due to some mismatch in data, we're now
> getting some information directly from the compiler.  See
>
>       http://gcc.gnu.org/ml/gcc-patches/2002-08/msg01672.html
>
> In the file
>
>      libstdc++-v3/config/cpu/ia64/cpu_limits.h
>
> I see the following
>
>     // While sizeof(long double) == 16, the format is the same as the x86.
>     #define __glibcpp_long_double_bits 80
>
> I don't know how exactly I should interpret that since 80 bits don't
> make 16 bytes.  I guess that means some bits are ignored.  If so I need
> to know exactly which ones.

It's like x86, just with 6 bytes padding instead of 2. So the first 10 bytes 
are the double.

BTW, x86-64 does exactly the same.

Bo.

-- 

     Bo Thorsen                 |   Praestevejen 4
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