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R=gri
DELTA=2  (2 added, 0 deleted, 0 changed)
OCL=30058
CL=30060
diff --git a/src/lib/runtime/darwin/thread.c b/src/lib/runtime/darwin/thread.c
index e5b5b9b..3a98247 100644
--- a/src/lib/runtime/darwin/thread.c
+++ b/src/lib/runtime/darwin/thread.c
@@ -323,6 +323,8 @@
 	Tmach_semdestroy = 3419,
 	Rmach_semdestroy = Tmach_semdestroy + Reply,
 
+	// Mach calls that get interrupted by Unix signals
+	// return this error code.  We retry them.
 	KERN_ABORTED = 14,
 };