Re: log2 on MinGW

[Rik]

On 11/04/2013 02:13 PM, Philip Nienhuis wrote:
> Rik wrote:
>> On 11/04/2013 09:54 AM, John W. Eaton wrote:
>>> On 11/04/2013 12:05 PM, Rik wrote:
>>>
>>>> Aside from performance, does using gnulib::frexp solve the original
>>>> problem? The gnulib documentation is somewhat minimal and they suggest
>>>> that they only replace an existing library function if the function is
>>>> buggy. Otherwise, they fall back on the library version that is
>>>> available. This may be, however, only when you use the bare function
>>>> such as 'frexp' rather than the namespace-qualified version
>>>> 'gnulib::frexp'.
>>>
>>> The namespace thing allows gnulib to replace the function in C++ code
>>> without introducing macros that screw things up in other places.  But the
>>> replacement code is still only used if needed.  It works by using a
>>> function pointer in the namespace that either refers to the replacement
>>> function (usually called rpl_FOO) or the system function FOO.  So there
>>> shouldn't be much of a penalty if the system function is used.
>> Philip,
>>
>> Can you test the solution which is in Mercurial with MinGW?  It is possible
>> that gnulib doesn't identify the frexp on Windows as being buggy (since it
>> works for ordinary values) in which case it won't replace it with the
>> correct version.
>
> Yes I'll try but only tomorrow night at the earliest, sorry.
> I've just finished io-1.2.4 which required more attention than I hoped for.
Independent testing is always great, but jwe has already gone ahead and
tested it.  If you're super busy then I don't think it's necessary to
replicate the test.

--Rik