Are casts encouraged in Rust?

I'd actually say that the C compilers are suboptimal here because they don't give a warning about line 13: if you want to get 0 directly, you should just use 0, and, in the more likely event that 65336 is coming from a macro or other constant and you want to just get the low bits into this constant (with the high bits going elsewhere), you should probably write it as VALUE & 0xffff, and I don't see any reason that writing (uint16_t) VALUE shouldn't give you a warning about the explicit cast resulting in a different constant value.