--- webkitgtk-2.52.1.old/Source/JavaScriptCore/runtime/JSCJSValue.h
+++ webkitgtk-2.52.1/Source/JavaScriptCore/runtime/JSCJSValue.h
@@ -1127,7 +1127,7 @@
     if (isInt32())
         return asInt32();
     double d = toNumber(globalObject);
-    return isnan(d) ? 0.0 : trunc(d) + 0.0;
+    return std::isnan(d) ? 0.0 : trunc(d) + 0.0;
 }
 
 inline bool JSValue::isUInt32() const
--- webkitgtk-2.52.1.old/Source/WebCore/rendering/RenderBox.h
+++ webkitgtk-2.52.1/Source/WebCore/rendering/RenderBox.h
@@ -695,7 +695,7 @@
 
     void computePreferredLogicalWidths(const Style::MinimumSize& minLogicalWidth, const Style::MaximumSize& maxLogicalWidth, LayoutUnit borderAndPaddingLogicalWidth);
 
-    bool isAspectRatioDegenerate(double aspectRatio) const { return !aspectRatio || isnan(aspectRatio); }
+    bool isAspectRatioDegenerate(double aspectRatio) const { return !aspectRatio || std::isnan(aspectRatio); }
 
     bool overflowChangesMayAffectLayout() const final;
 
--- webkitgtk-2.52.1.old/Source/WebCore/rendering/shapes/ShapeOutsideInfo.cpp
+++ webkitgtk-2.52.1/Source/WebCore/rendering/shapes/ShapeOutsideInfo.cpp
@@ -257,7 +257,7 @@
 
     auto logicalMargin = [&] {
         auto shapeMargin = Style::evaluate<LayoutUnit>(style.shapeMargin(), containingBlock.contentBoxLogicalWidth(), Style::ZoomNeeded { }).toFloat();
-        return isnan(shapeMargin) ? 0.0f : shapeMargin;
+        return std::isnan(shapeMargin) ? 0.0f : shapeMargin;
     }();
 
     return WTF::switchOn(shapeOutside,