diff --git a/core/base/src/TAttLine.cxx b/core/base/src/TAttLine.cxx
index c7da772e47a20571e27a5ef8ad4106f9117fd623..faa169df9acc627f43e437599d0d6060f47d2dca 100644
--- a/core/base/src/TAttLine.cxx
+++ b/core/base/src/TAttLine.cxx
@@ -20,7 +20,7 @@
 
 
 ClassImp(TAttLine)
-
+using std::sqrt;
 
 //______________________________________________________________________________
 /* Begin_Html
diff --git a/core/base/src/TColor.cxx b/core/base/src/TColor.cxx
index 1aecf4cd690f2e14b7e203ba62a15ac62f4683ef..4ebdec2a67912645151d5b1a363e015ff4c7a2ef 100644
--- a/core/base/src/TColor.cxx
+++ b/core/base/src/TColor.cxx
@@ -26,6 +26,7 @@ Bool_t  TColor::fgGrayscaleMode = kFALSE;
 Bool_t  TColor::fgInitDone = kFALSE;
 TArrayI TColor::fgPalette(0);
 
+using std::floor;
 
 //______________________________________________________________________________
 /* Begin_Html
diff --git a/geom/geom/src/TGeoElement.cxx b/geom/geom/src/TGeoElement.cxx
index 51f68af501489a38cfcfa482aa66a2bbe6471724..544d61a3c69c2055d746d86e2401c7928c10181a 100644
--- a/geom/geom/src/TGeoElement.cxx
+++ b/geom/geom/src/TGeoElement.cxx
@@ -518,15 +518,15 @@ void TGeoElementRN::SavePrimitive(std::ostream &out, Option_t *option)
    out << std::setw(5) << (Int_t)fA;
    out << std::setw(5) << fZ;
    out << std::setw(5) << fIso;
-   out << std::setw(10) << setiosflags(std::ios::fixed) << std::setprecision(5) << fLevel;
-   out << std::setw(10) << setiosflags(std::ios::fixed) << std::setprecision(5) << fDeltaM;
-   out << std::setw(10) << setiosflags(std::ios::scientific) << std::setprecision(3) << fHalfLife;
+   out << std::setw(10) << std::setiosflags(std::ios::fixed) << std::setprecision(5) << fLevel;
+   out << std::setw(10) << std::setiosflags(std::ios::fixed) << std::setprecision(5) << fDeltaM;
+   out << std::setw(10) << std::setiosflags(std::ios::scientific) << std::setprecision(3) << fHalfLife;
    out << std::setw(13) << fTitle.Data();
-   out << std::setw(10) << setiosflags(std::ios::fixed) << std::setprecision(5) << fNatAbun;
-   out << std::setw(10) << setiosflags(std::ios::fixed) << std::setprecision(5) << fTH_F;
-   out << std::setw(10) << setiosflags(std::ios::fixed) << std::setprecision(5) << fTG_F;
-   out << std::setw(10) << setiosflags(std::ios::fixed) << std::setprecision(5) << fTH_S;
-   out << std::setw(10) << setiosflags(std::ios::fixed) << std::setprecision(5) << fTG_S;
+   out << std::setw(10) << std::setiosflags(std::ios::fixed) << std::setprecision(5) << fNatAbun;
+   out << std::setw(10) << std::setiosflags(std::ios::fixed) << std::setprecision(5) << fTH_F;
+   out << std::setw(10) << std::setiosflags(std::ios::fixed) << std::setprecision(5) << fTG_F;
+   out << std::setw(10) << std::setiosflags(std::ios::fixed) << std::setprecision(5) << fTH_S;
+   out << std::setw(10) << std::setiosflags(std::ios::fixed) << std::setprecision(5) << fTG_S;
    out << std::setw(5) << fStatus;
    Int_t ndecays = 0;
    if (fDecays) ndecays = fDecays->GetEntries();
@@ -646,8 +646,8 @@ void TGeoDecayChannel::SavePrimitive(std::ostream &out, Option_t *)
    out << std::setw(50) << decayName.Data();
    out << std::setw(10) << fDecay;
    out << std::setw(10) << fDiso;
-   out << std::setw(12) << setiosflags(std::ios::fixed) << std::setprecision(6) << fBranchingRatio;
-   out << std::setw(12) << setiosflags(std::ios::fixed) << std::setprecision(6) << fQvalue;
+   out << std::setw(12) << std::setiosflags(std::ios::fixed) << std::setprecision(6) << fBranchingRatio;
+   out << std::setw(12) << std::setiosflags(std::ios::fixed) << std::setprecision(6) << fQvalue;
    out << std::endl;
 }
 
diff --git a/geom/geom/src/TGeoManager.cxx b/geom/geom/src/TGeoManager.cxx
index aaccd5531603710f4cdc03fa76a79127ec4d6cd5..7d7c9470a7870db793f3d666f215971750211762 100644
--- a/geom/geom/src/TGeoManager.cxx
+++ b/geom/geom/src/TGeoManager.cxx
@@ -272,6 +272,8 @@
 */
 //End_Html
 
+#include <stdlib.h>
+
 #include "Riostream.h"
 
 #include "TROOT.h"
diff --git a/graf3d/gl/src/TGLBoundingBox.cxx b/graf3d/gl/src/TGLBoundingBox.cxx
index 301090604d1ee18e1c5a8c76b01c848067e9e1f5..ee000292fbdc820d342851f274faa561f9191a8f 100644
--- a/graf3d/gl/src/TGLBoundingBox.cxx
+++ b/graf3d/gl/src/TGLBoundingBox.cxx
@@ -14,6 +14,8 @@
 #include "TGLIncludes.h"
 #include "TMathBase.h"
 
+using namespace std;
+
 //////////////////////////////////////////////////////////////////////////
 //                                                                      //
 // TGLBoundingBox                                                       //
diff --git a/io/io/src/TFile.cxx b/io/io/src/TFile.cxx
index fdc4a6cff7ed4bb23be621a99ef58a65af23f6ca..023c486040bd8c3676e5b94c93a4845d92e15653 100644
--- a/io/io/src/TFile.cxx
+++ b/io/io/src/TFile.cxx
@@ -118,6 +118,8 @@
 #include "TSchemaRuleSet.h"
 #include "TThreadSlots.h"
 
+using std::sqrt;
+
 Long64_t TFile::fgBytesRead  = 0;
 Long64_t TFile::fgBytesWrite = 0;
 Long64_t TFile::fgFileCounter = 0;
diff --git a/proof/proof/src/TProofServ.cxx b/proof/proof/src/TProofServ.cxx
index 5493f9f8282a24cd4d9a247bfbc0417cebfcfbb7..69e13f5843152c3b59bc6f54f4c06b283a711eff 100644
--- a/proof/proof/src/TProofServ.cxx
+++ b/proof/proof/src/TProofServ.cxx
@@ -44,6 +44,8 @@
 #include <exception>
 #include <new>
 
+using namespace std;
+
 #if (defined(__FreeBSD__) && (__FreeBSD__ < 4)) || \
     (defined(__APPLE__) && (!defined(MAC_OS_X_VERSION_10_3) || \
      (MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_3)))
diff --git a/proof/proof/src/TProofServLite.cxx b/proof/proof/src/TProofServLite.cxx
index 4f1b326dc3a44e0b748164d14c66f427ee7776c1..cbf3974e42499b66d475a47d431c5491f85c7b8b 100644
--- a/proof/proof/src/TProofServLite.cxx
+++ b/proof/proof/src/TProofServLite.cxx
@@ -55,6 +55,7 @@
 #include "TTimeStamp.h"
 #include "compiledata.h"
 
+using namespace std;
 
 // debug hook
 static volatile Int_t gProofServDebug = 1;
diff --git a/tmva/src/MethodANNBase.cxx b/tmva/src/MethodANNBase.cxx
index a5982e85b8ca522814d3dbd25ac665091ec6fe2f..5a620a76ae75fc26e700d8b6a3c58bf7c9b4089d 100644
--- a/tmva/src/MethodANNBase.cxx
+++ b/tmva/src/MethodANNBase.cxx
@@ -61,6 +61,7 @@
 
 using std::vector;
 using std::stringstream;
+using std::exit;
 
 ClassImp(TMVA::MethodANNBase)
 
diff --git a/tmva/src/MethodBase.cxx b/tmva/src/MethodBase.cxx
index b3df93a3141b6767135ca51de2d37e9c551035cc..701028c1c82cc083746ef4d62cb0aa49707dd7e0 100644
--- a/tmva/src/MethodBase.cxx
+++ b/tmva/src/MethodBase.cxx
@@ -112,6 +112,7 @@
 ClassImp(TMVA::MethodBase)
 
 using std::endl;
+using std::atof;
 
 const Int_t    MethodBase_MaxIterations_ = 200;
 const Bool_t   Use_Splines_for_Eff_      = kTRUE;
diff --git a/tmva/src/MethodCFMlpANN.cxx b/tmva/src/MethodCFMlpANN.cxx
index b96624678e77e37b5fe81c5cd55e2a6b444cf064..33e305fca22bab1de2d71676011033d9f7cc24be 100644
--- a/tmva/src/MethodCFMlpANN.cxx
+++ b/tmva/src/MethodCFMlpANN.cxx
@@ -81,6 +81,7 @@ REGISTER_METHOD(CFMlpANN)
 
 using std::stringstream;
 using std::make_pair;
+using std::atoi;
 
 ClassImp(TMVA::MethodCFMlpANN)
 
diff --git a/tmva/src/MethodCuts.cxx b/tmva/src/MethodCuts.cxx
index bc8ebed73586b71fb793a97fd49ee97adf2f1408..f5303cadd59a7e01862d011c1f3e4ae95ffac7de 100644
--- a/tmva/src/MethodCuts.cxx
+++ b/tmva/src/MethodCuts.cxx
@@ -114,6 +114,8 @@ End_Html */
 #include "TMVA/VariableTransformBase.h"
 #include "TMVA/Results.h"
 
+using std::atof;
+
 REGISTER_METHOD(Cuts)
 
 ClassImp(TMVA::MethodCuts)
diff --git a/tmva/src/MethodTMlpANN.cxx b/tmva/src/MethodTMlpANN.cxx
index 234d994be84ebdf5b86f89ebb99317c84bb3813a..ad6c889925bf196e4b735927d0176a0c51d70e69 100644
--- a/tmva/src/MethodTMlpANN.cxx
+++ b/tmva/src/MethodTMlpANN.cxx
@@ -65,6 +65,8 @@ End_Html */
 #include "TMVA/Tools.h"
 #endif
 
+using std::atoi;
+
 // some additional TMlpANN options
 const Bool_t EnforceNormalization__=kTRUE;
 #if ROOT_VERSION_CODE > ROOT_VERSION(5,13,06)
diff --git a/tree/treeplayer/src/TTreePlayer.cxx b/tree/treeplayer/src/TTreePlayer.cxx
index 9148a69a42e604de44222c479e30cd9c5ef2b42b..c77c783772bd644e6a58280c3df070ba9125c1b2 100644
--- a/tree/treeplayer/src/TTreePlayer.cxx
+++ b/tree/treeplayer/src/TTreePlayer.cxx
@@ -19,6 +19,7 @@
 
 #include <string.h>
 #include <stdio.h>
+#include <stdlib.h>
 
 #include "Riostream.h"
 #include "TTreePlayer.h"
@@ -81,6 +82,8 @@
 #include "Fit/UnBinData.h"
 #include "Math/MinimizerOptions.h"
 
+
+
 R__EXTERN Foption_t Foption;
 R__EXTERN  TTree *gTree;