strict aliasing violation in minisat/minisat.c

[Michael Orlitzky]

I think there's some undefined behavior in minisat/minisat.c that
happens to work out OK in most circumstances but that may cause
problems down the line, especially with link-time optimization. We have
a downstream bug report about the problem here,

  https://bugs.gentoo.org/863047

and I posted a patch there that hacks the types in minisat.c to make
the warnings/errors go away. Not sure if it's the best fix, but it
provides some evidence that we've diagnosed the right problem.