S+0 Union(size: 5)
S+8 Union(size: 5)
S+16 Union(size: 5)
S+24 Union(size: 5)
S+32 Union(size: 5)
S+40 Union(size: 5)
S+48 Union(size: 5)
S+56 Union(size: 5)
S+64 Union(size: 5)
S+72 Union(size: 5)
=>
P(rdi int64, ret:rax int64) Union(size: 5)