Re: [boost] [compute] Remove boost::chrono lib dependencie

Subject: Re: [boost] [compute] Remove boost::chrono lib dependencie
From: Gavin Lambert (gavinl_at_[hidden])
Date: 2016-12-01 01:07:26

On 1/12/2016 18:32, Kyle Lutz wrote:
>> Would it be possible to remove the dependency for boost/chrono is
>> boost/compute/detail/duration.hpp.
>>
>> As it already supports std::chrono via a macro, couldn't the inclusion of
>> boost/chrono.hpp be excluded?
>> As it is now, boost compute is dependent on having
>> libboost_chrono-vc140-mt-gd-1_62.lib built.
>
> Hi Viktor,
>
> You can remove the dependency on the Boost.Chrono compiled library by
> defining "BOOST_CHRONO_HEADER_ONLY" before including any Boost
> headers. See [1] for more details.

I think the request was to allow defining BOOST_COMPUTE_NO_BOOST_CHRONO 
or similar which conditionally excludes the Boost.Chrono includes in a 
similar fashion to the existing BOOST_COMPUTE_NO_HDR_CHRONO and std::chrono.

In a modular installation, this would mean that even the Boost.Chrono 
header files wouldn't be required to use Boost.Compute, in an 
environment where std::chrono is supported.

I did a quick search of the code out of curiosity, and while the tests 
and examples assume Boost.Chrono exists, it doesn't look like any of the 
actual Boost.Compute code requires it, except for 
make_duration_from_nanoseconds itself, which has a std::chrono alternate 
implementation.  (And it's called from a place where the duration type 
is templated, so should work with either.)