make use of <memory_resource> conditional on HAVE_STD_PMR_POLYMORPHIC_ALLOCATOR * mex.cc: Only include <memory_resource> if HAVE_STD_PMR_POLYMORPHIC_ALLOCATOR is defined.

root = true

[*]
charset = utf-8
end_of_line = lf
indent_size = 2
indent_style = space
insert_final_newline = true

[*.{am,mk}]
indent_size = tab
indent_style = tab