Also use logFactory for ThrowConfigExceptions

src/NLog/Config/XmlLoggingConfiguration.cs

@@ -515,7 +515,7 @@ private void ParseNLogElement(NLogXmlElement nlogElement, string filePath, bool
                 this.fileMustAutoReloadLookup[GetFileLookupKey(filePath)] = autoReload;
 
             logFactory.ThrowExceptions = nlogElement.GetOptionalBooleanAttribute("throwExceptions", logFactory.ThrowExceptions);
-            LogManager.ThrowConfigExceptions = nlogElement.GetOptionalBooleanAttribute("throwConfigExceptions", LogManager.ThrowConfigExceptions);
+            logFactory.ThrowConfigExceptions = nlogElement.GetOptionalBooleanAttribute("throwConfigExceptions", logFactory.ThrowConfigExceptions);
             InternalLogger.LogToConsole = nlogElement.GetOptionalBooleanAttribute("internalLogToConsole", InternalLogger.LogToConsole);
             InternalLogger.LogToConsoleError = nlogElement.GetOptionalBooleanAttribute("internalLogToConsoleError", InternalLogger.LogToConsoleError);
             InternalLogger.LogFile = nlogElement.GetOptionalAttribute("internalLogFile", InternalLogger.LogFile);
@@ -1190,4 +1190,4 @@ private string ExpandSimpleVariables(string input)
             return output;
         }
     }
-}
+}

src/NLog/Internal/TargetWithFilterChain.cs

@@ -31,6 +31,8 @@
 // THE POSSIBILITY OF SUCH DAMAGE.
 // 
 
+using System.Linq;
+
 namespace NLog.Internal
 {
     using System.Collections.Generic;
@@ -43,8 +45,8 @@ namespace NLog.Internal
     /// whether logging should happen.
     /// </summary>
     [NLogConfigurationItem]
-	internal class TargetWithFilterChain
-	{
+    internal class TargetWithFilterChain
+    {
         private StackTraceUsage stackTraceUsage = StackTraceUsage.None;
 
         /// <summary>
@@ -92,19 +94,10 @@ internal void PrecalculateStackTraceUsage()
 
             // find all objects which may need stack trace
             // and determine maximum
-            foreach (var item in ObjectGraphScanner.FindReachableObjects<IUsesStackTrace>(this))
+            // only the target can have IUsesStackTrace
+            if (Target != null)
             {
-                var stu = item.StackTraceUsage;
-
-                if (stu > this.stackTraceUsage)
-                {
-                    this.stackTraceUsage = stu;
-
-                    if (this.stackTraceUsage >= StackTraceUsage.Max)
-                    {
-                        break;
-                    }
-                }
+                this.stackTraceUsage = Target.GetAllLayouts().OfType<IUsesStackTrace>().DefaultIfEmpty().Max(usage => usage == null ? StackTraceUsage.None : usage.StackTraceUsage);
             }
         }
     }

src/NLog/Layouts/SimpleLayout.cs

@@ -31,6 +31,9 @@
 // THE POSSIBILITY OF SUCH DAMAGE.
 // 
 
+using System.Collections.Generic;
+using System.Linq;
+
 namespace NLog.Layouts
 {
     using System;
@@ -51,7 +54,7 @@ namespace NLog.Layouts
     [Layout("SimpleLayout")]
     [ThreadAgnostic]
     [AppDomainFixedOutput]
-    public class SimpleLayout : Layout
+    public class SimpleLayout : Layout, IUsesStackTrace
     {
         private const int MaxInitialRenderBufferLength = 16384;
         private int maxRenderedLength;
@@ -146,6 +149,13 @@ public string FixedText
         /// </summary>
         public ReadOnlyCollection<LayoutRenderer> Renderers { get; private set; }
 
+
+        /// <summary>
+        /// Gets the level of stack trace information required for rendering.
+        /// </summary>
+        /// <remarks>Calculated when setting <see cref="Renderers"/>.</remarks>
+        public StackTraceUsage StackTraceUsage { get; private set; }
+
         /// <summary>
         /// Converts a text to a simple layout.
         /// </summary>
@@ -208,17 +218,19 @@ public override string ToString()
         {
             return "'" + this.Text + "'";
         }
-
+ 
         internal void SetRenderers(LayoutRenderer[] renderers, string text)
         {
             this.Renderers = new ReadOnlyCollection<LayoutRenderer>(renderers);
             if (this.Renderers.Count == 1 && this.Renderers[0] is LiteralLayoutRenderer)
             {
                 this.fixedText = ((LiteralLayoutRenderer)this.Renderers[0]).Text;
+                this.StackTraceUsage = StackTraceUsage.None;
             }
             else
             {
                 this.fixedText = null;
+                this.StackTraceUsage = this.Renderers.OfType<IUsesStackTrace>().DefaultIfEmpty().Max(usage => usage == null ? StackTraceUsage.None : usage.StackTraceUsage);
             }
 
             this.layoutText = text;
@@ -287,5 +299,7 @@ protected override string GetFormattedMessage(LogEventInfo logEvent)
             logEvent.AddCachedLayoutValue(this, value);
             return value;
         }
+
+
     }
 }

src/NLog/Targets/Target.cs

@@ -50,6 +50,7 @@ public abstract class Target : ISupportsInitialize, IDisposable
     {
         private object lockObject = new object();
         private List<Layout> allLayouts;
+        private bool scannedForLayouts;
         private Exception initializeException;
 
         /// <summary>
@@ -76,6 +77,20 @@ protected object SyncRoot
         /// </summary>
         protected bool IsInitialized { get; private set; }
 
+        /// <summary>
+        /// Get all used layouts in this target.
+        /// </summary>
+        /// <returns></returns>
+        internal List<Layout> GetAllLayouts()
+        {
+
+            if (!scannedForLayouts)
+            {
+                FindAllLayouts();
+            }
+            return allLayouts;
+        }
+
         /// <summary>
         /// Initializes this instance.
         /// </summary>
@@ -396,9 +411,16 @@ protected virtual void Dispose(bool disposing)
         /// to initialize logging.
         /// </summary>
         protected virtual void InitializeTarget()
+        {
+            //rescan as amount layouts can be changed.
+            FindAllLayouts();
+        }
+
+        private void FindAllLayouts()
         {
             this.allLayouts = new List<Layout>(ObjectGraphScanner.FindReachableObjects<Layout>(this));
             InternalLogger.Trace("{0} has {1} layouts", this, this.allLayouts.Count);
+            this.scannedForLayouts = true;
         }
 
         /// <summary>