Is there any environment where “int” would cause struct padding?

Question

Specifically, this came up in a discussion:

Memory consuption wise, is there a possibility that using a struct of two ints t

Answer 1

It would not be totally implausible that a system which can only access memory in 64-bit chunks might have an option to use a 32-bit "int" size for compatibility with other programs that could get tripped up of uint32_t promotes to a larger type. On such a system, a struct with an even number of "int" values would likely not have extra padding, but one with an odd number of values might plausibly do so.

From a practical perspective, the only way a struct with two int values would need padding would be if the alignment of a struct was more than twice as coarse as that of "int". That would in turn require either that the alignment of structures be coarser than 64 bits, or that the size of int be smaller than 32 bits. The latter situation wouldn't be unusual in and of itself, but combining both in a fashion that would make struct alignment more than twice as coarse as int alignment would seem very weird.