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diff --git a/src/system_wrappers/source/atomic32_linux.h b/src/system_wrappers/source/atomic32_linux.h
new file mode 100644
index 0000000000..f9f5650f2a
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+++ b/src/system_wrappers/source/atomic32_linux.h
@@ -0,0 +1,119 @@
+/*
+ *  Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+// Atomic system independant 32-bit signed integer.
+// Linux implementation.
+// Note: Requires gcc 4.1.2 or later.
+#ifndef WEBRTC_SYSTEM_WRAPPERS_SOURCE_ATOMIC32_LINUX_H_
+#define WEBRTC_SYSTEM_WRAPPERS_SOURCE_ATOMIC32_LINUX_H_
+
+#include <inttypes.h>
+#include <malloc.h>
+
+#include "common_types.h"
+
+namespace webrtc {
+class Atomic32Impl
+{
+public:
+    inline Atomic32Impl(WebRtc_Word32 initialValue);
+    inline ~Atomic32Impl();
+
+    inline WebRtc_Word32 operator++();
+    inline WebRtc_Word32 operator--();
+
+    inline Atomic32Impl& operator=(const Atomic32Impl& rhs);
+    inline Atomic32Impl& operator=(WebRtc_Word32 rhs);
+    inline WebRtc_Word32 operator+=(WebRtc_Word32 rhs);
+    inline WebRtc_Word32 operator-=(WebRtc_Word32 rhs);
+
+    inline bool CompareExchange(WebRtc_Word32 newValue,
+                                WebRtc_Word32 compareValue);
+
+    inline WebRtc_Word32 Value() const;
+private:
+    void*        _ptrMemory;
+    // Volatile ensures full memory barriers.
+    volatile WebRtc_Word32* _value;
+};
+
+// TODO (hellner) use aligned_malloc instead of doing it manually.
+inline Atomic32Impl::Atomic32Impl(WebRtc_Word32 initialValue)
+    : _ptrMemory(NULL),
+      _value(NULL)
+{   // Align the memory associated with _value on a 32-bit boundary. This is a
+    // requirement for the used Linux APIs to be atomic.
+    // Keep _ptrMemory to be able to reclaim memory.
+    _ptrMemory = malloc(sizeof(WebRtc_Word32)*2);
+    _value = (WebRtc_Word32*) (((uintptr_t)_ptrMemory+3)&(~0x3));
+    *_value = initialValue;
+}
+
+inline Atomic32Impl::~Atomic32Impl()
+{
+    if(_ptrMemory != NULL)
+    {
+        free(_ptrMemory);
+    }
+}
+
+inline WebRtc_Word32 Atomic32Impl::operator++()
+{
+    WebRtc_Word32 returnValue = __sync_fetch_and_add(_value,1);
+    returnValue++;
+    return returnValue;
+}
+
+inline WebRtc_Word32 Atomic32Impl::operator--()
+{
+    WebRtc_Word32 returnValue = __sync_fetch_and_sub(_value,1);
+    returnValue--;
+    return returnValue;
+}
+
+inline Atomic32Impl& Atomic32Impl::operator=(const Atomic32Impl& rhs)
+{
+    *_value = *rhs._value;
+    return *this;
+}
+
+inline Atomic32Impl& Atomic32Impl::operator=(WebRtc_Word32 rhs)
+{
+    *_value = rhs;
+    return *this;
+}
+
+inline WebRtc_Word32 Atomic32Impl::operator+=(WebRtc_Word32 rhs)
+{
+    WebRtc_Word32 returnValue = __sync_fetch_and_add(_value,rhs);
+    returnValue += rhs;
+    return returnValue;
+}
+
+inline WebRtc_Word32 Atomic32Impl::operator-=(WebRtc_Word32 rhs)
+{
+    WebRtc_Word32 returnValue = __sync_fetch_and_sub(_value,rhs);
+    returnValue -= rhs;
+    return returnValue;
+}
+
+inline bool Atomic32Impl::CompareExchange(WebRtc_Word32 newValue,
+                                          WebRtc_Word32 compareValue)
+{
+    return __sync_bool_compare_and_swap(_value,compareValue,newValue);
+}
+
+inline WebRtc_Word32 Atomic32Impl::Value() const
+{
+    return *_value;
+}
+} // namespace webrtc
+
+#endif // WEBRTC_SYSTEM_WRAPPERS_SOURCE_ATOMIC32_LINUX_H_