1 files changed, 73 insertions, 0 deletions
diff --git a/src/runtime/proc.go b/src/runtime/proc.go
index 48b8cbe39..27e84230a 100644
--- a/src/runtime/proc.go
+++ b/src/runtime/proc.go
@@ -6,6 +6,79 @@ package runtime
 
 import "unsafe"
 
+func newsysmon()
+
+func runtime_init()
+func main_init()
+func main_main()
+
+// The main goroutine.
+func main() {
+	g := getg()
+
+	// Racectx of m0->g0 is used only as the parent of the main goroutine.
+	// It must not be used for anything else.
+	g.m.g0.racectx = 0
+
+	// Max stack size is 1 GB on 64-bit, 250 MB on 32-bit.
+	// Using decimal instead of binary GB and MB because
+	// they look nicer in the stack overflow failure message.
+	if ptrSize == 8 {
+		maxstacksize = 1000000000
+	} else {
+		maxstacksize = 250000000
+	}
+
+	onM(newsysmon)
+
+	// Lock the main goroutine onto this, the main OS thread,
+	// during initialization.  Most programs won't care, but a few
+	// do require certain calls to be made by the main thread.
+	// Those can arrange for main.main to run in the main thread
+	// by calling runtime.LockOSThread during initialization
+	// to preserve the lock.
+	lockOSThread()
+
+	// Defer unlock so that runtime.Goexit during init does the unlock too.
+	needUnlock := true
+	defer func() {
+		if needUnlock {
+			unlockOSThread()
+		}
+	}()
+
+	if g.m != &m0 {
+		gothrow("runtime.main not on m0")
+	}
+
+	runtime_init()
+	memstats.enablegc = true // now that runtime is initialized, GC is okay
+
+	main_init()
+
+	needUnlock = false
+	unlockOSThread()
+
+	main_main()
+	if raceenabled {
+		racefini()
+	}
+
+	// Make racy client program work: if panicking on
+	// another goroutine at the same time as main returns,
+	// let the other goroutine finish printing the panic trace.
+	// Once it does, it will exit. See issue 3934.
+	if panicking != 0 {
+		gopark(nil, nil, "panicwait")
+	}
+
+	exit(0)
+	for {
+		var x *int32
+		*x = 0
+	}
+}
+
 var parkunlock_c byte
 
 // start forcegc helper goroutine