--- a/dom/media/platforms/omx/OmxPlatformLayer.cpp
+++ b/dom/media/platforms/omx/OmxPlatformLayer.cpp
@@ -44,17 +44,17 @@ typedef OmxConfig<AudioInfo> OmxAudioCon
 typedef OmxConfig<VideoInfo> OmxVideoConfig;
 
 template<typename ConfigType>
 UniquePtr<ConfigType> ConfigForMime(const nsACString&);
 
 static OMX_ERRORTYPE
 ConfigAudioOutputPort(OmxPlatformLayer& aOmx, const AudioInfo& aInfo)
 {
-  OMX_ERRORTYPE err;
+  OMX_ERRORTYPE err = OMX_ErrorNone;
 
   OMX_PARAM_PORTDEFINITIONTYPE def;
   InitOmxParameter(&def);
   def.nPortIndex = aOmx.OutputPortIndex();
   err = aOmx.GetParameter(OMX_IndexParamPortDefinition, &def, sizeof(def));
   RETURN_IF_ERR(err);
 
   def.format.audio.eEncoding = OMX_AUDIO_CodingPCM;
@@ -82,17 +82,17 @@ ConfigAudioOutputPort(OmxPlatformLayer& 
   return OMX_ErrorNone;
 }
 
 class OmxAacConfig : public OmxAudioConfig
 {
 public:
   OMX_ERRORTYPE Apply(OmxPlatformLayer& aOmx, const AudioInfo& aInfo) override
   {
-    OMX_ERRORTYPE err;
+    OMX_ERRORTYPE err = OMX_ErrorNone;
 
     OMX_AUDIO_PARAM_AACPROFILETYPE aacProfile;
     InitOmxParameter(&aacProfile);
     aacProfile.nPortIndex = aOmx.InputPortIndex();
     err = aOmx.GetParameter(OMX_IndexParamAudioAac, &aacProfile, sizeof(aacProfile));
     RETURN_IF_ERR(err);
 
     aacProfile.nChannels = aInfo.mChannels;
@@ -108,17 +108,17 @@ public:
   }
 };
 
 class OmxMp3Config : public OmxAudioConfig
 {
 public:
   OMX_ERRORTYPE Apply(OmxPlatformLayer& aOmx, const AudioInfo& aInfo) override
   {
-    OMX_ERRORTYPE err;
+    OMX_ERRORTYPE err = OMX_ErrorNone;
 
     OMX_AUDIO_PARAM_MP3TYPE mp3Param;
     InitOmxParameter(&mp3Param);
     mp3Param.nPortIndex = aOmx.InputPortIndex();
     err = aOmx.GetParameter(OMX_IndexParamAudioMp3, &mp3Param, sizeof(mp3Param));
     RETURN_IF_ERR(err);
 
     mp3Param.nChannels = aInfo.mChannels;
@@ -139,17 +139,17 @@ enum OmxAmrSampleRate {
 };
 
 template <OmxAmrSampleRate R>
 class OmxAmrConfig : public OmxAudioConfig
 {
 public:
   OMX_ERRORTYPE Apply(OmxPlatformLayer& aOmx, const AudioInfo& aInfo) override
   {
-    OMX_ERRORTYPE err;
+    OMX_ERRORTYPE err = OMX_ErrorNone;
 
     OMX_AUDIO_PARAM_AMRTYPE def;
     InitOmxParameter(&def);
     def.nPortIndex = aOmx.InputPortIndex();
     err = aOmx.GetParameter(OMX_IndexParamAudioAmr, &def, sizeof(def));
     RETURN_IF_ERR(err);
 
     def.eAMRFrameFormat = OMX_AUDIO_AMRFrameFormatFSF;
@@ -191,17 +191,17 @@ class OmxCommonVideoConfig : public OmxV
 {
 public:
   explicit OmxCommonVideoConfig()
     : OmxVideoConfig()
   {}
 
   OMX_ERRORTYPE Apply(OmxPlatformLayer& aOmx, const VideoInfo& aInfo) override
   {
-    OMX_ERRORTYPE err;
+    OMX_ERRORTYPE err = OMX_ErrorNone;
     OMX_PARAM_PORTDEFINITIONTYPE def;
 
     // Set up in/out port definition.
     nsTArray<uint32_t> ports;
     aOmx.GetPortIndices(ports);
     for (auto idx : ports) {
       InitOmxParameter(&def);
       def.nPortIndex = idx;