--- a/graal/com.oracle.max.graal.debug/src/com/oracle/max/graal/debug/internal/DebugScope.java	Thu Jan 26 17:26:42 2012 +0100
+++ b/graal/com.oracle.max.graal.debug/src/com/oracle/max/graal/debug/internal/DebugScope.java	Thu Jan 26 18:33:58 2012 +0100
@@ -44,7 +44,6 @@
     private DebugValueMap valueMap;
     private String qualifiedName;
 
-    public static final DebugScope DEFAULT_CONTEXT = new DebugScope("DEFAULT", "DEFAULT", null);
     private static final char SCOPE_SEP = '.';
 
     private boolean logEnabled;
@@ -55,7 +54,7 @@
     public static DebugScope getInstance() {
         DebugScope result = instanceTL.get();
         if (result == null) {
-            instanceTL.set(new DebugScope("DEFAULT", "DEFAULT", null));
+            instanceTL.set(new DebugScope("", "", null));
             return instanceTL.get();
         } else {
             return result;
@@ -107,6 +106,8 @@
         }
     }
 
+    private static Object lock = new Object();
+
     public <T> T scope(String newName, Runnable runnable, Callable<T> callable, boolean sandbox, Object[] newContext) {
         DebugScope oldContext = getInstance();
         DebugConfig oldConfig = getConfig();
@@ -118,15 +119,30 @@
             newChild = oldContext.createChild(newName, newContext);
         }
         instanceTL.set(newChild);
-        T result = null;
         newChild.updateFlags();
-        newChild.log("Starting scope %s", newChild.getQualifiedName());
         try {
+            if (logEnabled || dumpEnabled) {
+                synchronized (lock) {
+                    return executeScope(runnable, callable);
+                }
+            } else {
+                return executeScope(runnable, callable);
+            }
+        } finally {
+            newChild.deactivate();
+            instanceTL.set(oldContext);
+            setConfig(oldConfig);
+        }
+    }
+
+    private <T> T executeScope(Runnable runnable, Callable<T> callable) {
+        try {
+            instanceTL.get().log("Starting scope %s", instanceTL.get().getQualifiedName());
             if (runnable != null) {
                 runnable.run();
             }
             if (callable != null) {
-                result = call(callable);
+                return call(callable);
             }
         } catch (RuntimeException e) {
             if (e == lastExceptionThrownTL.get()) {
@@ -136,12 +152,8 @@
                 lastExceptionThrownTL.set(newException);
                 throw newException;
             }
-        } finally {
-            newChild.deactivate();
-            instanceTL.set(oldContext);
-            setConfig(oldConfig);
         }
-        return result;
+        return null;
     }
 
     private void updateFlags() {
@@ -195,7 +207,10 @@
     }
 
     private DebugScope createChild(String newName, Object[] newContext) {
-        String newQualifiedName = this.qualifiedName + SCOPE_SEP + newName;
+        String newQualifiedName = newName;
+        if (this.qualifiedName.length() > 0) {
+            newQualifiedName = this.qualifiedName + SCOPE_SEP + newName;
+        }
         DebugScope result = new DebugScope(newName, newQualifiedName, this, newContext);
         if (children == null) {
             children = new ArrayList<>(4);