lib: Don't try to read uninitialized memory
lib: Don't try to read uninitialized memory

Oddly this uninitialized memory read leads to a seg fault on ARM but
not on x86_64.

Closes: #1621
Approved by: mwleeds

matthiasclasen/flatpak,matthiasclasen/flatpak,matthiasclasen/flatpak,flatpak/flatpak,flatpak/flatpak,matthiasclasen/flatpak,matthiasclasen/flatpak,flatpak/flatpak,flatpak/flatpak,flatpak/flatpak