diff --git a/packager/app/test/testdata/audio-video-with-two-trick-play/output.mpd b/packager/app/test/testdata/audio-video-with-two-trick-play/output.mpd
index 785c185548..06363446d4 100644
--- a/packager/app/test/testdata/audio-video-with-two-trick-play/output.mpd
+++ b/packager/app/test/testdata/audio-video-with-two-trick-play/output.mpd
@@ -12,15 +12,15 @@
     </AdaptationSet>
     <AdaptationSet id="1" contentType="video" width="640" height="360" maxFrameRate="30000/30030" par="16:9">
       <EssentialProperty schemeIdUri="http://dashif.org/guidelines/trickmode" value="0"/>
-      <Representation id="1" bandwidth="211545" codecs="avc1.64001e" mimeType="video/mp4" sar="1:1" frameRate="30000/60060" maxPlayoutRate="60" codingDependency="false">
-        <BaseURL>bear-640x360-video-trick_play_factor_2.mp4</BaseURL>
-        <SegmentBase indexRange="859-914" timescale="30000">
+      <Representation id="1" bandwidth="211545" codecs="avc1.64001e" mimeType="video/mp4" sar="1:1" frameRate="30000/30030" maxPlayoutRate="30" codingDependency="false">
+        <BaseURL>bear-640x360-video-trick_play_factor_1.mp4</BaseURL>
+        <SegmentBase indexRange="859-926" timescale="30000">
           <Initialization range="0-858"/>
         </SegmentBase>
       </Representation>
-      <Representation id="2" bandwidth="211545" codecs="avc1.64001e" mimeType="video/mp4" sar="1:1" frameRate="30000/30030" maxPlayoutRate="30" codingDependency="false">
-        <BaseURL>bear-640x360-video-trick_play_factor_1.mp4</BaseURL>
-        <SegmentBase indexRange="859-926" timescale="30000">
+      <Representation id="2" bandwidth="211545" codecs="avc1.64001e" mimeType="video/mp4" sar="1:1" frameRate="30000/60060" maxPlayoutRate="60" codingDependency="false">
+        <BaseURL>bear-640x360-video-trick_play_factor_2.mp4</BaseURL>
+        <SegmentBase indexRange="859-914" timescale="30000">
           <Initialization range="0-858"/>
         </SegmentBase>
       </Representation>
diff --git a/packager/app/test/testdata/encryption-and-two-trick-plays/output.mpd b/packager/app/test/testdata/encryption-and-two-trick-plays/output.mpd
index f2cb141877..29c07d0482 100644
--- a/packager/app/test/testdata/encryption-and-two-trick-plays/output.mpd
+++ b/packager/app/test/testdata/encryption-and-two-trick-plays/output.mpd
@@ -20,15 +20,15 @@
         <cenc:pssh>AAAANHBzc2gBAAAAEHfv7MCyTQKs4zweUuL7SwAAAAExMjM0NTY3ODkwMTIzNDU2AAAAAA==</cenc:pssh>
       </ContentProtection>
       <EssentialProperty schemeIdUri="http://dashif.org/guidelines/trickmode" value="0"/>
-      <Representation id="1" bandwidth="212297" codecs="avc1.64001e" mimeType="video/mp4" sar="1:1" frameRate="30000/60060" maxPlayoutRate="60" codingDependency="false">
-        <BaseURL>bear-640x360-video-trick_play_factor_2.mp4</BaseURL>
-        <SegmentBase indexRange="1127-1182" timescale="30000">
+      <Representation id="1" bandwidth="212297" codecs="avc1.64001e" mimeType="video/mp4" sar="1:1" frameRate="30000/30030" maxPlayoutRate="30" codingDependency="false">
+        <BaseURL>bear-640x360-video-trick_play_factor_1.mp4</BaseURL>
+        <SegmentBase indexRange="1127-1194" timescale="30000">
           <Initialization range="0-1126"/>
         </SegmentBase>
       </Representation>
-      <Representation id="2" bandwidth="212297" codecs="avc1.64001e" mimeType="video/mp4" sar="1:1" frameRate="30000/30030" maxPlayoutRate="30" codingDependency="false">
-        <BaseURL>bear-640x360-video-trick_play_factor_1.mp4</BaseURL>
-        <SegmentBase indexRange="1127-1194" timescale="30000">
+      <Representation id="2" bandwidth="212297" codecs="avc1.64001e" mimeType="video/mp4" sar="1:1" frameRate="30000/60060" maxPlayoutRate="60" codingDependency="false">
+        <BaseURL>bear-640x360-video-trick_play_factor_2.mp4</BaseURL>
+        <SegmentBase indexRange="1127-1182" timescale="30000">
           <Initialization range="0-1126"/>
         </SegmentBase>
       </Representation>
diff --git a/packager/packager.cc b/packager/packager.cc
index 82ba9a2ab5..b3a2aafd25 100644
--- a/packager/packager.cc
+++ b/packager/packager.cc
@@ -317,15 +317,16 @@ Status ValidateParams(const PackagingParams& packaging_params,
 
 bool StreamDescriptorCompareFn(const StreamDescriptor& a,
                                const StreamDescriptor& b) {
+  // This function is used by std::sort() to sort the stream descriptors.
+  // Note that std::sort() need a comparator that return true iff the first
+  // argument is strictly lower than the second one. That is: must return false
+  // when they are equal. The requirement is enforced in gcc/g++ but not in
+  // clang.
   if (a.input == b.input) {
     if (a.stream_selector == b.stream_selector) {
       // The MPD notifier requires that the main track comes first, so make
       // sure that happens.
-      if (a.trick_play_factor == 0 || b.trick_play_factor == 0) {
-        return a.trick_play_factor == 0;
-      } else {
-        return a.trick_play_factor > b.trick_play_factor;
-      }
+      return a.trick_play_factor < b.trick_play_factor;
     } else {
       return a.stream_selector < b.stream_selector;
     }