--- /dev/null	2019-10-01 11:37:31.106015611 +0200
+++ new/src/hotspot/os/windows/gc/z/zSyscall_windows.cpp	2019-10-31 09:39:47.165080748 +0100
@@ -0,0 +1,58 @@
+/*
+ * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+#include "precompiled.hpp"
+#include "gc/z/zSyscall_windows.hpp"
+#include "logging/log.hpp"
+#include "runtime/java.hpp"
+#include "runtime/os.hpp"
+
+ZSyscall::CreateFileMappingWFn ZSyscall::CreateFileMappingW;
+ZSyscall::VirtualAlloc2Fn ZSyscall::VirtualAlloc2;
+ZSyscall::VirtualFreeExFn ZSyscall::VirtualFreeEx;
+ZSyscall::MapViewOfFile3Fn ZSyscall::MapViewOfFile3;
+ZSyscall::UnmapViewOfFile2Fn ZSyscall::UnmapViewOfFile2;
+
+template <typename Fn>
+static void lookup_symbol(Fn*& fn, const char* library, const char* symbol) {
+  char ebuf[1024];
+  void* const handle = os::dll_load(library, ebuf, sizeof(ebuf));
+  if (handle == NULL) {
+    log_error(gc)("Failed to load library: %s", library);
+    vm_exit_during_initialization("ZGC requires Windows version 1803 or later");
+  }
+
+  fn = reinterpret_cast<Fn*>(os::dll_lookup(handle, symbol));
+  if (fn == NULL) {
+    log_error(gc)("Failed to lookup symbol: %s", symbol);
+    vm_exit_during_initialization("ZGC requires Windows version 1803 or later");
+  }
+}
+
+void ZSyscall::initialize() {
+  lookup_symbol(CreateFileMappingW, "KernelBase", "CreateFileMappingW");
+  lookup_symbol(VirtualAlloc2,      "KernelBase", "VirtualAlloc2");
+  lookup_symbol(VirtualFreeEx,      "KernelBase", "VirtualFreeEx");
+  lookup_symbol(MapViewOfFile3,     "KernelBase", "MapViewOfFile3");
+  lookup_symbol(UnmapViewOfFile2,   "KernelBase", "UnmapViewOfFile2");
+}