If I use `_ = my_variable` would that mean that variable would never be even made?

[rocky dragon]

const my_variable = ... // a sum of numbers i wanted to see whether its causing a slowdown or not, this is just a plain sum of some fields from a struct
_ = my_variable

would my_variable even be computated?

[copper lark]

if the computation doesn't have side effects, up to the optimizer

you can use std.mem.doNotOptimizeAway to force it to be calculated