runtime: provide a dummy value of _SIGPROF on plan9 and windows

Fixes build on plan9 and windows.

Change-Id: Ic9b02c641ab84e4f6d8149de71b9eb495e3343b2
Reviewed-on: https://go-review.googlesource.com/2233Reviewed-by: Alex Brainman <alex.brainman@gmail.com>

src/runtime/defs_windows.go

@@ -41,6 +41,7 @@ const (
 	DUPLICATE_SAME_ACCESS   = C.DUPLICATE_SAME_ACCESS
 	THREAD_PRIORITY_HIGHEST = C.THREAD_PRIORITY_HIGHEST
 
+	SIGPROF          = 0 // dummy value for badsignal
 	SIGINT           = C.SIGINT
 	CTRL_C_EVENT     = C.CTRL_C_EVENT
 	CTRL_BREAK_EVENT = C.CTRL_BREAK_EVENT

src/runtime/defs_windows_386.go

@@ -15,6 +15,7 @@ const (
 	_DUPLICATE_SAME_ACCESS   = 0x2
 	_THREAD_PRIORITY_HIGHEST = 0x2
 
+	_SIGPROF          = 0 // dummy value for badsignal
 	_SIGINT           = 0x2
 	_CTRL_C_EVENT     = 0x0
 	_CTRL_BREAK_EVENT = 0x1

src/runtime/defs_windows_amd64.go

@@ -15,6 +15,7 @@ const (
 	_DUPLICATE_SAME_ACCESS   = 0x2
 	_THREAD_PRIORITY_HIGHEST = 0x2
 
+	_SIGPROF          = 0 // dummy value for badsignal
 	_SIGINT           = 0x2
 	_CTRL_C_EVENT     = 0x0
 	_CTRL_BREAK_EVENT = 0x1

src/runtime/os2_plan9.go

@@ -69,4 +69,6 @@ const (
 	_SIGINTDIV = 4
 	_SIGFLOAT  = 5
 	_SIGTRAP   = 6
+	// dummy value defined for badsignal
+	_SIGPROF   = 0
 )

src/runtime/sigqueue.go

@@ -160,8 +160,13 @@ func badsignal(sig uintptr) {
 	// call to cgocallback below will bring down the whole process.
 	// It's better to miss a few SIGPROF signals than to abort in this case.
 	// See http://golang.org/issue/9456.
-	if sig == _SIGPROF && needextram != 0 {
-		return
+	switch GOOS {
+	case "windows", "plan9":
+		// no actual SIGPROF is defined, nothing to do
+	default:
+		if sig == _SIGPROF && needextram != 0 {
+			return
+		}
 	}
 	cgocallback(unsafe.Pointer(funcPC(sigsend)), noescape(unsafe.Pointer(&sig)), unsafe.Sizeof(sig))
 }