gcc-10: a couple of small fixes to build with gcc-10
a couple of small fixes to build with gcc-10 (20191229 snapshot)
gcc-10 is stricter about certain things than gcc-9.
More info about gcc-10 changes at https://gcc.gnu.org/gcc-10/changes.html
Apparently there's still a decent chance that gcc-10 will make it into
Fedora-32 despite having missed the cut-off of 2019-12-31.