diff --git a/dom/media/webaudio/blink/HRTFPanner.cpp b/dom/media/webaudio/blink/HRTFPanner.cpp
index 94b2d6b8d8e4..98a94dc78e0d 100644
--- a/dom/media/webaudio/blink/HRTFPanner.cpp
+++ b/dom/media/webaudio/blink/HRTFPanner.cpp
@@ -102,9 +102,6 @@ int HRTFPanner::calculateDesiredAzimuthIndexAndBlend(double azimuth, double& azi
     if (azimuth < 0)
         azimuth += 360.0;
 
-    HRTFDatabase* database = m_databaseLoader->database();
-    MOZ_ASSERT(database);
-
     int numberOfAzimuths = HRTFDatabase::numberOfAzimuths();
     const double angleBetweenAzimuths = 360.0 / numberOfAzimuths;
 
diff --git a/layout/style/RuleProcessorCache.h b/layout/style/RuleProcessorCache.h
index c30413e969a1..723b39d0b319 100644
--- a/layout/style/RuleProcessorCache.h
+++ b/layout/style/RuleProcessorCache.h
@@ -74,16 +74,13 @@ private:
       : nsExpirationTracker<nsCSSRuleProcessor,3>(
           10000, "RuleProcessorCache::ExpirationTracker",
           SystemGroup::EventTargetFor(TaskCategory::Other))
-      , mCache(aCache) {}
+      {}
 
     void RemoveObjectIfTracked(nsCSSRuleProcessor* aRuleProcessor);
 
     virtual void NotifyExpired(nsCSSRuleProcessor* aRuleProcessor) override {
       mozilla::RuleProcessorCache::RemoveRuleProcessor(aRuleProcessor);
     }
-
-  private:
-    RuleProcessorCache* mCache;
   };
 
   RuleProcessorCache() : mExpirationTracker(this) {}
diff --git a/layout/svg/nsSVGIntegrationUtils.cpp b/layout/svg/nsSVGIntegrationUtils.cpp
index c2c00cba37e5..03662b559e50 100644
--- a/layout/svg/nsSVGIntegrationUtils.cpp
+++ b/layout/svg/nsSVGIntegrationUtils.cpp
@@ -214,7 +214,6 @@ nsSVGIntegrationUtils::GetSVGCoordContextForNonSVGFrame(nsIFrame* aNonSVGFrame)
   nsIFrame* firstFrame =
     nsLayoutUtils::FirstContinuationOrIBSplitSibling(aNonSVGFrame);
   nsRect r = nsLayoutUtils::GetAllInFlowRectsUnion(firstFrame, firstFrame);
-  nsPresContext* presContext = firstFrame->PresContext();
   return gfx::Size(nsPresContext::AppUnitsToFloatCSSPixels(r.width),
                    nsPresContext::AppUnitsToFloatCSSPixels(r.height));
 }
diff --git a/layout/xul/nsMenuPopupFrame.cpp b/layout/xul/nsMenuPopupFrame.cpp
index bf9c03c5ae6f..e14bdb19b7c0 100644
--- a/layout/xul/nsMenuPopupFrame.cpp
+++ b/layout/xul/nsMenuPopupFrame.cpp
@@ -2411,7 +2411,6 @@ nsMenuPopupFrame::MoveTo(const CSSIntPoint& aPos, bool aUpdateAttrs)
                      LookAndFeel::eIntID_ContextMenuOffsetVertical));
   }
 
-  nsPresContext* presContext = PresContext();
   mAnchorType = MenuPopupAnchorType_Point;
   mScreenRect.x = aPos.x - nsPresContext::AppUnitsToIntCSSPixels(margin.left);
   mScreenRect.y = aPos.y - nsPresContext::AppUnitsToIntCSSPixels(margin.top);