[erik_seaberg]

Bypassing libc and its header files, which are generally the up to date source of truth about things like enum values and struct layouts.

[ptidhomme]

But what's specific to Go ? It's a generalized practice there ?

[erik_seaberg]

I think Go tried to do this everywhere (from the same impulse that drove them to write their own linker?) but systems other than Linux are not committing to support a stable ABI from userland into their kernels.