diff --git a/lib/ace/VirtualRenderer.js b/lib/ace/VirtualRenderer.js
index 67bb1482..2e31c6a1 100644
--- a/lib/ace/VirtualRenderer.js
+++ b/lib/ace/VirtualRenderer.js
@@ -376,7 +376,7 @@ var VirtualRenderer = function(container, theme) {
         var widthChanged = !this.layerConfig ? true : (this.layerConfig.width != longestLine);
 
         var lineCount = Math.ceil(minHeight / this.lineHeight);
-        var firstRow = Math.max(Math.round((this.scrollTop - offset) / this.lineHeight, 0));
+        var firstRow = Math.max(0, Math.round((this.scrollTop - offset) / this.lineHeight));
         var lastRow = Math.min(this.lines.length, firstRow + lineCount) - 1;
 
         var layerConfig = this.layerConfig = {