--- a/gfx/thebes/gfxFont.cpp
+++ b/gfx/thebes/gfxFont.cpp
@@ -2592,17 +2592,17 @@ gfxFont::GetShapedWord(DrawTarget *aDraw
     }
 
     // if there's a cached entry for this word, just return it
     CacheHashKey key(aText, aLength, aHash,
                      aRunScript,
                      aAppUnitsPerDevUnit,
                      aFlags, aRounding);
 
-    CacheHashEntry *entry = mWordCache->PutEntry(key);
+    CacheHashEntry* entry = mWordCache->PutEntry(key, fallible);
     if (!entry) {
         NS_WARNING("failed to create word cache entry - expect missing text");
         return nullptr;
     }
     gfxShapedWord* sw = entry->mShapedWord.get();
 
     if (sw) {
         sw->ResetAge();