Here's a post where I walk through the assembly generated by some different approaches. http://neugierig.org/software/blog/2011/12/return-by-value.html http://n

Here's a post where I walk through the assembly generated by some different approaches. http://neugierig.org/software/blog/2011/12/return-by-value.html http://neugierig.org/software/blog/2011/12/return-by-value.h... One possibility is that OpenBSD uses the alternative ABI for returning structs mentioned in that post.