x/sys/unix: F_OK removed with OpenBSD 6.3 amd64 update

[mpx]

The OpenBSD 6.3 rebuild for amd64 (golang/sys@7f59abf) incorrectly removed F_OK (used by access(2)). I'm not sure if all the other changes were correct or not.

@FiloSottile @tklauser

[gopherbot]

Change https://golang.org/cl/126635 mentions this issue: unix: fix openbsd/amd64 codegen to include F_OK

[mpx]

I've reviewed all the that were removed in the openbsd/amd64 generated code from golang/sys@7f59abf to master.

It looks like F_OK is the only symbol that was removed that should still be present. Most of the remaining symbols are no longer found under /usr/include/... in OpenBSD 6.3, and a few are not part of the userspace API.

F_OK is defined in sys/unistd.h. I suspect it was implicitly included as a dependency when the code was generated ages ago, but this is no longer the case after OS/compiler header changes. I haven't installed/reviewed old OpenBSD versions to confirm if this is possible, but it's my best guess.

The above CL adds sys/unistd.h to the list of headers which then fixes the code generation.

Status of OpenBSD/amd64 unix package symbols in OpenBSD 6.3:

F_OK                     // Present in sys/unistd.h (used by access(2)).
IFA_ROUTE                // Present in net/if_var.h (kernel only).
IFF_NOTRAILERS           // Removed. Value reused for IFF_STATICARP.
IPPROTO_DIVERT_INIT      // Removed. 
IPPROTO_DIVERT_RESP      // Removed. 
IP_DIVERTFL              // Removed.
MAP_INHERIT_DONATE_COPY  // Removed. Value reused for MAP_INHERIT_ZERO.
RTF_MASK                 // Removed. 
RTF_SOURCE               // Removed.
RTF_TUNNEL               // Removed.
RTF_XRESOLVE             // Removed. Value reused for RTF_MULTICAST.
SIOCALIFADDR             // Removed. 
SIOCBRDGGSIFS            // Removed.
SIOCDLIFADDR             // Removed. 
SIOCGHIWAT               // Removed. 
SIOCGIFASYNCMAP          // Removed. 
SIOCGIFPDSTADDR          // Removed. 
SIOCGIFPSRCADDR          // Removed. 
SIOCGIFTIMESLOT          // Removed. 
SIOCGLIFADDR             // Removed. 
SIOCGLOWAT               // Removed. 
SIOCSHIWAT               // Removed. 
SIOCSIFASYNCMAP          // Removed. 
SIOCSIFPHYADDR           // Removed. 
SIOCSIFTIMESLOT          // Removed. 
SIOCSLOWAT               // Removed. 
SYS_GETLOGIN             // Removed. Replaced with SYS_GETLOGIN_R.
SYS___SYSCTL             // Removed. Replaced with SYS_SYSCTL.
TCP_NSTATES              // Present in netinet/tcp_fsm.h (kernel only).
WSTOPPED                 // Removed (now _WSTOPPED).