runtime: initialize crashFD to -1
crashFD defaults to the zero value of (surprise!) zero. Zero is a valid
FD, so on the first call to SetCrashOutput we actually close FD 0 since
it is a "valid" FD.
Initialize crashFD to -1, the sentinel for "no FD".
Change-Id: I3b108c60603f2b83b867cbe079f035c159b6a6ca
Reviewed-on: https://go-review.googlesource.com/c/go/+/560776
Reviewed-by: Alan Donovan <adonovan@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
diff --git a/src/runtime/proc.go b/src/runtime/proc.go
index a7a3fb6..538ed0a 100644
--- a/src/runtime/proc.go
+++ b/src/runtime/proc.go
@@ -775,6 +775,7 @@
}
sched.maxmcount = 10000
+ crashFD.Store(^uintptr(0))
// The world starts stopped.
worldStopped()
diff --git a/src/runtime/runtime.go b/src/runtime/runtime.go
index 4dfb2f8..c7a511b 100644
--- a/src/runtime/runtime.go
+++ b/src/runtime/runtime.go
@@ -244,6 +244,8 @@
// set by debug.SetCrashOutput (see #42888). If it is a valid fd (not
// all ones), writeErr and related functions write to it in addition
// to standard error.
+//
+// Initialized to -1 in schedinit.
var crashFD atomic.Uintptr
//go:linkname setCrashFD
