diff --git a/src/google/protobuf/stubs/once.cc b/src/google/protobuf/stubs/once.cc
index e69de29b..9f565be4 100644
--- a/src/google/protobuf/stubs/once.cc
+++ b/src/google/protobuf/stubs/once.cc
@@ -0,0 +1,45 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+//
+// Author: medinaandres@google.com (Andres Medina)
+//
+// Unlines GoogleOnceInit
+
+#include <google/protobuf/stubs/once.h>
+
+namespace google {
+namespace protobuf {
+
+void GoogleOnceInit(ProtobufOnceType* once, void (*init_func)()) {
+  std::call_once(*once, init_func);
+}
+
+}  // namespace protobuf
+}  // namespace google
diff --git a/src/google/protobuf/stubs/once.h b/src/google/protobuf/stubs/once.h
index f3835ccd..b6d9fea3 100644
--- a/src/google/protobuf/stubs/once.h
+++ b/src/google/protobuf/stubs/once.h
@@ -96,9 +96,7 @@ void call_once(Args&&... args ) {
 // TODO(gerbens) remove this once third_party is fully extracted
 using ProtobufOnceType = internal::once_flag;
 
-inline void GoogleOnceInit(ProtobufOnceType* once, void (*init_func)()) {
-  std::call_once(*once, init_func);
-}
+void GoogleOnceInit(ProtobufOnceType* once, void (*init_func)());
 
 template <typename Arg>
 inline void GoogleOnceInitArg(ProtobufOnceType* once, void (*init_func)(Arg*),