diff --git a/core/macosx/src/TMacOSXSystem.mm b/core/macosx/src/TMacOSXSystem.mm
index 8dc7f9e0d2d66b26fac3eb039d4912963a9c59be..341783c5f28c098e8398a106c4f86036d8258176 100644
--- a/core/macosx/src/TMacOSXSystem.mm
+++ b/core/macosx/src/TMacOSXSystem.mm
@@ -9,20 +9,21 @@
  * For the list of contributors see $ROOTSYS/README/CREDITS.             *
  *************************************************************************/
 
-#include <stdexcept>
-#include <vector>
-#include <map>
-#include <set>
+#include "TMacOSXSystem.h"
 
 #include <Cocoa/Cocoa.h>
 
-#include "TSeqCollection.h"
-#include "TMacOSXSystem.h"
 #include "CocoaUtils.h"
 #include "TVirtualX.h"
 #include "TError.h"
 #include "TROOT.h"
 
+#include <stdexcept>
+#include <vector>
+#include <map>
+#include <set>
+
+class TSeqCollection;
 //Handle deprecated symbols
 namespace ROOT {
 namespace MacOSX {
diff --git a/graf3d/eve/inc/TEveBrowser.h b/graf3d/eve/inc/TEveBrowser.h
index 723398c64cda8d9c3601c284756531fb5515a0cc..223704f9a598ff53d1346431a3f54e511209a3af 100644
--- a/graf3d/eve/inc/TEveBrowser.h
+++ b/graf3d/eve/inc/TEveBrowser.h
@@ -14,10 +14,11 @@
 
 #include "TEveElement.h"
 
-#include "TRootBrowser.h"
+#include "TContextMenu.h"
 #include "TGListTree.h"
+#include "TRootBrowser.h"
+#include "TString.h"
 
-#include "TContextMenu.h"
 
 class TGFileBrowser;
 class TGSplitter;
diff --git a/graf3d/gl/src/TGLPlotBox.cxx b/graf3d/gl/src/TGLPlotBox.cxx
index 216746cc08093818722137ed6ba8cd84c594165e..6b79a49221130073e87da85fb44eb5838295ed82 100644
--- a/graf3d/gl/src/TGLPlotBox.cxx
+++ b/graf3d/gl/src/TGLPlotBox.cxx
@@ -9,12 +9,13 @@
  * For the list of contributors see $ROOTSYS/README/CREDITS.             *
  *************************************************************************/
 
-#include <algorithm>
+#include "TGLPlotBox.h"
 
 #include "TColor.h"
-
 #include "TGLIncludes.h"
-#include "TGLPlotBox.h"
+
+#include <algorithm>
+
 
 /** \class TGLPlotBox
 \ingroup opengl
diff --git a/math/quadp/inc/TQpSolverBase.h b/math/quadp/inc/TQpSolverBase.h
index 7fc833f960d4e75a8f81d8a88c5756a40d160bd9..af448ee8df68a78ba237f208b474360b2ec9e9ab 100644
--- a/math/quadp/inc/TQpSolverBase.h
+++ b/math/quadp/inc/TQpSolverBase.h
@@ -47,6 +47,7 @@
 #include "TError.h"
 #endif
 
+#include "TObject.h"
 #ifndef ROOT_TQpVar
 #include "TQpVar.h"
 #endif
diff --git a/misc/table/inc/TChair.h b/misc/table/inc/TChair.h
index 9105027a80812f734e1e851d180443bb9399ff6b..964466051b8fc219e8eb7ef503e90b43f7013865 100644
--- a/misc/table/inc/TChair.h
+++ b/misc/table/inc/TChair.h
@@ -22,6 +22,8 @@
 
 #include "TTable.h"
 
+#include "TCut.h"
+
 class TChair : public TDataSet {
 
 protected:
diff --git a/net/http/inc/TCivetweb.h b/net/http/inc/TCivetweb.h
index 326acda4329d90dd63194cacf00e533c2779ae89..1566ce2f81b9c63d2222ab7893647b0c8766c35a 100644
--- a/net/http/inc/TCivetweb.h
+++ b/net/http/inc/TCivetweb.h
@@ -7,6 +7,7 @@
 #ifndef ROOT_THttpEngine
 #include "THttpEngine.h"
 #endif
+#include "TString.h"
 
 class TCivetweb : public THttpEngine {
 protected:
diff --git a/roofit/roostats/inc/RooStats/AsymptoticCalculator.h b/roofit/roostats/inc/RooStats/AsymptoticCalculator.h
index 175b5cf64a226dd984637fb9f324dcf102efc974..12c60a784fc358c3935aa8c5eea4471bf166cf35 100644
--- a/roofit/roostats/inc/RooStats/AsymptoticCalculator.h
+++ b/roofit/roostats/inc/RooStats/AsymptoticCalculator.h
@@ -11,13 +11,15 @@
 #ifndef ROOSTATS_AsymptoticCalculator
 #define ROOSTATS_AsymptoticCalculator
 
-
-
 #ifndef ROOSTATS_HypoTestCalculatorGeneric
 #include "RooStats/HypoTestCalculatorGeneric.h"
 #endif
+#include "RooArgSet.h"
+#include "Rtypes.h"
 
-class RooArgSet;
+class RooArgList;
+class RooCategory;
+class RooRealVar;
 class RooPoisson;
 class RooProdPdf;