const runtime.stackFromSystem

3 uses

	runtime (current package)
		stack.go#L109: 	stackFromSystem  = 0 // allocate stacks from system memory instead of the heap
		stack.go#L351: 	if debug.efence != 0 || stackFromSystem != 0 {
		stack.go#L453: 	if debug.efence != 0 || stackFromSystem != 0 {