[lmi] Another compiler upgrade [Was: "buster" updates]

[Greg Chicares]

On 2018-04-07 18:27, Vadim Zeitlin wrote:
[...]
>  Anyhow, the only important question here is whether we're going to update
> the compiler used under Cygwin to 7.3 (the files for it are available at
> https://sourceforge.net/projects/mingw-w64/files/Toolchains%20targetting%20Win32/)
> or downgrade the packages used for cross-compiling? We could also ignore
> the difference between 7.2 and 7.3 as the only important one is that 7.3
> supports "retpolines" that mitigate Spectre/Meltdown attacks on the code
> compiled with it, but we don't really care about this with lmi. However it
> would still arguably better, for our collective peace of mind, to use the
> same compiler version everywhere.

I'll test everything as far as possible in my chroot this weekend.
If I find a serious problem, then backing up to 7.2 might become
the best option. Otherwise, moving to 7.3 everywhere is probably
best; I'll have to consult with Kim. She's already hoping to
upgrade wx next week, which requires rebuilding lmi. Upgrading the
compiler at the same time probably doesn't take a lot more work,
but it's not negligible either.