--- a/media/libstagefright/frameworks/av/media/libstagefright/MPEG4Extractor.cpp
+++ b/media/libstagefright/frameworks/av/media/libstagefright/MPEG4Extractor.cpp
@@ -406,17 +406,17 @@ status_t MPEG4Extractor::readMetaData() 
 
     off64_t offset = 0;
     status_t err = NO_INIT;
     while (!mFirstTrack) {
         err = parseChunk(&offset, 0);
         // The parseChunk function returns UNKNOWN_ERROR to skip
         // some boxes we don't want to handle. Filter that error
         // code but return others so e.g. I/O errors propagate.
-        if (err != OK && err != (status_t) UNKNOWN_ERROR) {
+        if (err != OK && err != static_cast<status_t>(UNKNOWN_ERROR)) {
           ALOGW("Error %d parsing chunck at offset %lld looking for first track",
               err, (long long)offset);
           break;
         }
     }
 
     if (mInitCheck == OK) {
         if (mHasVideo) {
@@ -622,17 +622,17 @@ status_t MPEG4Extractor::parseDrmSINF(of
             size -= (dataLen + numOfBytes + 1);
         }
     }
 
     if (size != 0) {
         return ERROR_MALFORMED;
     }
 
-    return UNKNOWN_ERROR;  // Return a dummy error.
+    return static_cast<status_t>(UNKNOWN_ERROR);  // Return a dummy error.
 }
 
 struct PathAdder {
     PathAdder(nsTArray<uint32_t> *path, uint32_t chunkType)
         : mPath(path) {
         mPath->AppendElement(chunkType);
     }
 
@@ -840,17 +840,17 @@ status_t MPEG4Extractor::parseChunk(off6
 
                 if (err != OK) {
                     return err;
                 }
             } else if (chunk_type == FOURCC('m', 'o', 'o', 'v')) {
                 mInitCheck = OK;
 
                 if (!mIsDrm) {
-                    return UNKNOWN_ERROR;  // Return a dummy error.
+                    return static_cast<status_t>(UNKNOWN_ERROR);  // Return a dummy error.
                 } else {
                     return OK;
                 }
             }
             break;
         }
 
         case FOURCC('e', 'l', 's', 't'):
@@ -1974,17 +1974,17 @@ status_t MPEG4Extractor::parseChunk(off6
             *offset += chunk_size;
             break;
         }
 
         case FOURCC('s', 'i', 'd', 'x'):
         {
             parseSegmentIndex(data_offset, chunk_data_size);
             *offset += chunk_size;
-            return UNKNOWN_ERROR; // stop parsing after sidx
+            return static_cast<status_t>(UNKNOWN_ERROR); // stop parsing after sidx
         }
 
         case FOURCC('w', 'a', 'v', 'e'):
         {
             off64_t stop_offset = *offset + chunk_size;
             *offset = data_offset;
             while (*offset < stop_offset) {
                 status_t err = parseChunk(offset, depth + 1);