This should be #include <__tuple>
This line should be gone.
Clean some minor cruft from src/experimental/memory_resource.cpp. (This part is a separate git commit which I could pull-request if you want it separately.)
I wonder if memory_resource needs a key function for its vtable; consider the precedent of D27387. But out-of-lining a trivial destructor just to avoid -Wweak-vtables feels kind of awful.
Experimental and std differ in their implementation of options() because the latter needs to be compileable as -std=c++11 whereas the former gets to use -std=c++14.
Rebased on master.
The previous patch had replaced test/support/test_memory_resource.hpp with the two files test/support/test_experimental_memory_resource.hpp and test/support/test_memory_resource.hpp (and edited all the experimental tests to use the former).
This new patch replaces test/support/test_memory_resource.h with the two files test/support/test_memory_resource.h and test/support/test_std_memory_resource.h (which reduces the diff by leaving the experimental tests untouched in this patch).