On Thu, Jun 16, 2022 at 01:40:34PM +0000, Christophe Leroy wrote:

sizeof(u64) is always 8 by definition.

So if size is 8 we are working on a binary file for a 64 bits target, if 
not it means we are working for a 32 bits target.

Cross-builds invalidate this I think. Best to look at something like:

  elf->ehdr.e_ident[EI_CLASS] == ELFCLASS32