- The -Wno-deprecated-copy flag for gcc-9.2.0
In the future we may indeed wish to explicitly request default
generated constructors and assignment operators, but at the moment
these are still acceptable.
- The -Wno-alloc-size-larger-than flag for mingw compilations
Related to differences in PTRDIFF_MAX vs SIZE_MAX on the target.
Several issues related to this can be found in the gcc bug reports
and on stackoverflow etc.
