[Numpy-discussion] Solaris Sparc build broken

David Cournapeau cournape@gmail....
Fri Nov 6 11:10:49 CST 2009


On Sat, Nov 7, 2009 at 12:05 AM, Charles R Harris
<charlesr.harris@gmail.com> wrote:
>
>
> On Fri, Nov 6, 2009 at 12:10 AM, David Cournapeau
> <david@ar.media.kyoto-u.ac.jp> wrote:
>>
>> Charles R Harris wrote:
>> >
>> >
>> > On Thu, Nov 5, 2009 at 10:35 PM, David Cournapeau
>> > <david@ar.media.kyoto-u.ac.jp <mailto:david@ar.media.kyoto-u.ac.jp>>
>> > wrote:
>> >
>> >     Charles R Harris wrote:
>> >     > So you are going to leave us all hanging here in curiosity? What
>> > is
>> >     > your solution?
>> >
>> >     I had to sleep :)
>> >
>> >     The solution is based on parsing the generated binary code -
>> >     that's how
>> >     MPFR is doing it, so it has been tested in the wild. The code to
>> >     compile
>> >     is something like:
>> >
>> >     /* "before" is 16 bytes to ensure there's no padding between it
>> >     and "x".
>> >      *    We're not expecting any "long double" bigger than 16 bytes
>> >     or with
>> >      *       alignment requirements stricter than 16 bytes.  */
>> >     typedef long double test_type;
>> >
>> >     struct {
>> >            char         before[16];
>> >            test_type    x;
>> >            char         after[8];
>> >     } foo = {
>> >            { '\0', '\0', '\0', '\0', '\0', '\0', '\0', '\0',
>> >              '\001', '\043', '\105', '\147', '\211', '\253', '\315',
>> >     '\357' },
>> >            -123456789.0,
>> >            { '\376', '\334', '\272', '\230', '\166', '\124', '\062',
>> >     '\020' }
>> >     };
>> >
>> >     They compile it, parse with awk from the dump od -f.
>> >
>> >
>> > So the before/after bits are tags that mark the beginning/end of the
>> > type for the parse? Any particular reason not to use a string?
>> As for why not using my name, I am not that megalomaniac, at least not
>> yet :)
>>
>> od prints a dump in octal form, so a string is not much more readable. I
>> am not sure why they use od instead of another dump format - but there
>> is value if keeping the same format as them for testing, all other
>> things being equal.
>>
>
> Is od available on all platforms? Couldn't you just read the file using
> Python?

That's actually what I have done. I am pretty sure windows does not
had od, for once :)

It seems to work pretty well on every platform I have tested. Once I
take the time to fix the configuration for universal build, I will use
those for low level long double handling, to implement nextafterl -
this WE hopefully

David


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