Currently there is only a single default target used for all C emission.
However, the emitted code is actually compiled using multiple
implementations (32-bit and 64-bit targets), some of which use a 32-bit
wide long. This causes integer literals to be emitted with wrong sizes
on those targets. This change forces all 64-bit literals to be emitted
using long long, which is 64 bits wide in all relevant implementations.
Lauri Vasama