Can C arrays contain padding in between elements?

Question

I heard a rumor that, in C, arrays that are contained inside structs may have padding added in between elements of the array. Now obviously, the amount of padding could not

Answer 1

Careful here. Padding may be added at the end of the struct, but will not be added between the elements of the array as you state in your question. Arrays will always reference contiguous memory, though an array of structures may have padding added to each element as part of the struct itself.

In your example, the values and foo.values arrays will have the same size. Any padding will be part of the struct foo instead.