From: Russ Cox <rsc@golang.org>
Date: Tue, 25 Oct 2016 00:47:31 +0000 (-0400)
Subject: runtime: accept timeout from non-timeout semaphore wait on OS X
X-Git-Tag: go1.8beta1~657
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=71cf409dbdcba20f220d65ab83a6494c1f79b2a0;p=gostls13.git

runtime: accept timeout from non-timeout semaphore wait on OS X

Looking at the kernel sources, I don't see how this is possible.
But obviously it is. Just try again.

Fixes #17161.

Change-Id: Iea7d53f7cf75944792d2f75a0d07129831c7bcdb
Reviewed-on: https://go-review.googlesource.com/31823
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
---

diff --git a/src/runtime/os_darwin.go b/src/runtime/os_darwin.go
index fa5aca2f99..0dfe8778db 100644
--- a/src/runtime/os_darwin.go
+++ b/src/runtime/os_darwin.go
@@ -414,7 +414,10 @@ func semasleep1(ns int64) int32 {
 		if r == 0 {
 			break
 		}
-		if r == _KERN_ABORTED { // interrupted
+		// Note: We don't know how this call (with no timeout) can get _KERN_OPERATION_TIMED_OUT,
+		// but it does reliably, though at a very low rate, on OS X 10.8, 10.9, 10.10, and 10.11.
+		// See golang.org/issue/17161.
+		if r == _KERN_ABORTED || r == _KERN_OPERATION_TIMED_OUT { // interrupted
 			continue
 		}
 		macherror(r, "semaphore_wait")