Re: [boost] [lexical_cast][math] can't unconditionally call math::changesign with long double

Subject: Re: [boost] [lexical_cast][math] can't unconditionally call math::changesign with long double
From: Antony Polukhin (antoshkka_at_[hidden])
Date: 2013-02-24 01:51:27

2013/2/24 Jeroen Habraken <vexocide_at_[hidden]>:
> On 23 February 2013 18:53, Eric Niebler <eniebler_at_[hidden]> wrote:
>
>> lexical_cast is using math::changesign with long double regardless of
>> whether BOOST_MATH_NO_LONG_DOUBLE_MATH_FUNCTIONS is defined or not. This
>> is causing Boost.Test build problems (see here http://tinyurl.com/af5453h
>> ).
>>
>> I'm pretty sure this is a bug in lexical_cast, so I've opened a ticket:
>> https://svn.boost.org/trac/boost/ticket/8162

So, portable way of changing sign is just to multiply on -1 ?
And math::isnan I shall change to value != value ?
And math::isinf to something like value >= numeric_limits<>::max?

But why don't we do that in Boost.Math?

>> I've assigned it to the last person to touch lexical_cast.hpp. Apologies
>> if that's not right. There is no entry for lexical_cast in
>> libs/maintainers.txt.
>
>
> You've assigned it to the right person, Antony has become the new
> maintainer of lexical_cast as per
> http://lists.boost.org/Archives/boost/2011/05/181523.php. This is also
> reflected in  https://svn.boost.org/trac/boost/report/15 and should
> probably be added to libs/maintainers.txt.

I'll commit changes to libs/maintainers.txt today.

--
Best regards,
Antony Polukhin