diff --git a/ipc/glue/CrossProcessMutex.h b/ipc/glue/CrossProcessMutex.h
index 77e8f117a1e..9167df4bdaa 100644
--- a/ipc/glue/CrossProcessMutex.h
+++ b/ipc/glue/CrossProcessMutex.h
@@ -9,7 +9,7 @@
 #include "base/process.h"
 #include "mozilla/Mutex.h"
 
-#if defined(OS_LINUX) || defined(OS_MACOSX)
+#if defined(OS_LINUX) || defined(XP_DARWIN)
 #include <pthread.h>
 #include "SharedMemoryBasic.h"
 #include "mozilla/Atomics.h"
diff --git a/ipc/glue/SharedMemoryBasic.h b/ipc/glue/SharedMemoryBasic.h
index 223e735b34d..f3f729121c7 100644
--- a/ipc/glue/SharedMemoryBasic.h
+++ b/ipc/glue/SharedMemoryBasic.h
@@ -10,7 +10,7 @@
 
 #ifdef ANDROID
 #  include "mozilla/ipc/SharedMemoryBasic_android.h"
-#elif defined(XP_MACOSX)
+#elif defined(XP_DARWIN)
 #  include "mozilla/ipc/SharedMemoryBasic_mach.h"
 #else
 #  include "mozilla/ipc/SharedMemoryBasic_chromium.h"
diff --git a/ipc/glue/SharedMemoryBasic_mach.cpp b/ipc/glue/SharedMemoryBasic_mach.mm
similarity index 98%
rename from ipc/glue/SharedMemoryBasic_mach.cpp
rename to ipc/glue/SharedMemoryBasic_mach.mm
index a2dc8c59e81..c4667ad97be 100644
--- a/ipc/glue/SharedMemoryBasic_mach.cpp
+++ b/ipc/glue/SharedMemoryBasic_mach.mm
@@ -9,7 +9,18 @@
 
 #include <mach/vm_map.h>
 #include <mach/mach_port.h>
+#if defined(XP_IOS)
+#include <mach/vm_map.h>
+#define mach_vm_address_t vm_address_t
+#define mach_vm_allocate vm_allocate
+#define mach_vm_deallocate vm_deallocate
+#define mach_vm_map vm_map
+#define mach_vm_read vm_read
+#define mach_vm_region_recurse vm_region_recurse_64
+#define mach_vm_size_t vm_size_t
+#else
 #include <mach/mach_vm.h>
+#endif
 #include <pthread.h>
 #include <unistd.h>
 #include "SharedMemoryBasic.h"
diff --git a/ipc/glue/moz.build b/ipc/glue/moz.build
index 1786fb7c15c..e0d4c476461 100644
--- a/ipc/glue/moz.build
+++ b/ipc/glue/moz.build
@@ -80,7 +80,7 @@ if CONFIG['OS_TARGET'] == 'Android':
 elif CONFIG['OS_ARCH'] == 'Darwin':
     EXPORTS.mozilla.ipc += ['SharedMemoryBasic_mach.h']
     SOURCES += [
-        'SharedMemoryBasic_mach.cpp',
+        'SharedMemoryBasic_mach.mm',
     ]
 else:
     EXPORTS.mozilla.ipc += ['SharedMemoryBasic_chromium.h']