--- a/dom/media/platforms/ffmpeg/ffvpx/FFVPXRuntimeLinker.cpp
+++ b/dom/media/platforms/ffmpeg/ffvpx/FFVPXRuntimeLinker.cpp
@@ -27,17 +27,21 @@ FFVPXRuntimeLinker::LinkStatus FFVPXRunt
   LinkStatus_INIT;
 
 static PRLibrary*
 MozAVLink(const char* aName)
 {
   PRLibSpec lspec;
   lspec.type = PR_LibSpec_Pathname;
   lspec.value.pathname = aName;
-  return PR_LoadLibraryWithFlags(lspec, PR_LD_NOW | PR_LD_LOCAL);
+  PRLibrary* lib = PR_LoadLibraryWithFlags(lspec, PR_LD_NOW | PR_LD_LOCAL);
+  if (!lib) {
+    FFMPEG_LOG("unable to load library %s", aName);
+  }
+  return lib;
 }
 
 /* static */ bool
 FFVPXRuntimeLinker::Init()
 {
   if (sLinkStatus) {
     return sLinkStatus == LinkStatus_SUCCEEDED;
   }