Re: Issue 5368: Reduce allocations in Grob dimension caching (issue 359770043 by address@hidden)

[Hans Åberg]

> On 7 Jul 2018, at 10:04, David Kastrup <address@hidden> wrote:
> 
> Hans Åberg <address@hidden> writes:
> 
>> The idea is to do it all now, then the change is automatic and the old
>> code can just be removed at some point in time, but you would need a
>> compiler that can do C++17, too.
> 
> The whole point is that we do not want to rely on C++17 now and don't
> want to maintain a full reimplementation of a C++17 feature until we do
> when that feature is used only once and in a minor manner.  The fallover
> strategy for it becoming available is not really of relevance for that
> call, but an automatic fallover would mean that we have dormant untested
> code that becomes active at different points of time for different
> people.

The first step would probably to switch to a later compiler with a flag for an 
older C++ version. Then one can test later C++ versions in independent builds.