diff --git a/CMakeLists.txt b/CMakeLists.txt
index fb370f05..9fcac2a1 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -244,7 +244,7 @@ if (NLOPT_CXX)
     src/algs/ags/ags.h
     src/algs/ags/ags.cc)
 
-set_property(SOURCE src/algs/ags/solver.cc src/algs/ags/local_optimizer.cc src/algs/ags/ags.cc src/algs/slsqp/slsqp.c src/algs/stogo/linalg.cc
+set_property(SOURCE src/algs/ags/solver.cc src/algs/ags/local_optimizer.cc src/algs/ags/ags.cc src/algs/slsqp/slsqp.c
              PROPERTY SKIP_UNITY_BUILD_INCLUSION ON)
 endif ()
 
diff --git a/src/algs/stogo/global.cc b/src/algs/stogo/global.cc
index 8b572152..b8e8d0ac 100644
--- a/src/algs/stogo/global.cc
+++ b/src/algs/stogo/global.cc
@@ -213,11 +213,11 @@ void Global::Search(int axis, RCRVector x_av){
       ReduceOrSubdivide(box, axis, x_av);
 
       if (!NoMinimizers() && OneMinimizer(x) < stop->minf_max) {
-        done = TRUE;
+        done = true;
         break;
       }
       if (!InTime()) {
-        done=TRUE;
+        done=true;
 	if (stogo_verbose)
 	  cout << "The program has run out of time or function evaluations\n";
         break;
diff --git a/src/algs/stogo/linalg.cc b/src/algs/stogo/linalg.cc
index 04916cf0..7111eb95 100644
--- a/src/algs/stogo/linalg.cc
+++ b/src/algs/stogo/linalg.cc
@@ -4,7 +4,7 @@
 */
 
 #include <iostream>
-#include <math.h>         // for sqrt()
+#include <cmath>         // for sqrt()
 
 #include "linalg.h"
 
@@ -32,7 +32,9 @@ RVector::RVector() {
 RVector::RVector(int n) {
  // Constructor
  len=n;
- elements=new double[len]; (*this)=0.;
+ if (n > 0)
+   elements = new double[len];
+ (*this)=0.;
 }
 
 RVector::RVector(RCRVector vect)
diff --git a/src/algs/stogo/linalg.h b/src/algs/stogo/linalg.h
index d5b8d7bb..b8b8b345 100644
--- a/src/algs/stogo/linalg.h
+++ b/src/algs/stogo/linalg.h
@@ -8,8 +8,8 @@
 
 #include <iostream>
 using namespace std;
-#include <math.h>         // for sqrt()
-#include <float.h>
+#include <cmath>         // for sqrt()
+#include <cfloat>
 
 typedef const class RVector CRVector;
 typedef CRVector& RCRVector;
@@ -18,17 +18,14 @@ typedef CRMatrix& RCRMatrix;
 
 double eps() ;
 
-#define max(A,B)    ((A) > (B) ? (A):(B))
-#define min(A,B)    ((A) < (B) ? (A):(B))
-
 /********************* Class RVector *********************/
 
 class RVector{
 protected:
 
  public:
-  int      len;       // size of array
-  double*  elements;  // array of values
+  int      len = 0;       // size of array
+  double*  elements = nullptr;  // array of values
 
   RVector() ;
   RVector(int);       // Constructor
diff --git a/src/algs/stogo/tools.cc b/src/algs/stogo/tools.cc
index 5b49be4f..92c3cb2b 100644
--- a/src/algs/stogo/tools.cc
+++ b/src/algs/stogo/tools.cc
@@ -96,7 +96,7 @@ double TBox::GetMin() {
 }
 
 bool TBox::EmptyBox() {
-  // Returns TRUE if the list of Trials is empty
+  // Returns true if the list of Trials is empty
   return TList.empty() ;
 }
 
@@ -137,7 +137,7 @@ void TBox::ClearBox() {
 }
 
 bool TBox::CloseToMin(RVector &vec, double *objval, double eps_cl) {
-  // Returns TRUE if 'vec' is close to some of the trials in the box,
+  // Returns true if 'vec' is close to some of the trials in the box,
   // in this case, 'vec' and 'objval' are overwritten by the Trial data
   // otherwise 'vec' and 'objval' are not affected.
   //
@@ -155,10 +155,10 @@ bool TBox::CloseToMin(RVector &vec, double *objval, double eps_cl) {
     if (norm2(y)<=eps_cl) {
       vec=x;
       *objval=(*itr).objval;
-      return TRUE;
+      return true;
     }
   }
-  return FALSE;
+  return false;
 }
 
 int TBox::NStationary() {
@@ -247,11 +247,11 @@ ostream & operator << (ostream & os, const TBox & B) {
 }
 
 bool TBox::InsideBox(RCRVector x) {
-  // Returns TRUE if the point X lies inside BOX, FALSE otherwise
+  // Returns true if the point X lies inside BOX, false otherwise
   int n=GetDim();
   for (int i=0 ; i<n ; i++)
-    if (x(i)<lb(i) || x(i)>ub(i)) return FALSE;
-  return TRUE;
+    if (x(i)<lb(i) || x(i)>ub(i)) return false;
+  return true;
 }
 
 int TBox::OutsideBox(RCRVector x, RCTBox domain) {
@@ -349,7 +349,7 @@ bool TBox::Intersection(RCRVector x, RCRVector h, RCRVector z) {
 //   Due to round of errors the algorithm can fail to find an intersection
 //   The caller is notified and should act accordingly
 //
-//  The routine returns FALSE if no intersection was found, TRUE otherwise
+//  The routine returns false if no intersection was found, true otherwise
 
   int n=GetDim();
   RVector tmpV(n);
@@ -357,8 +357,8 @@ bool TBox::Intersection(RCRVector x, RCRVector h, RCRVector z) {
   int i, j, k, isect;
   double alpha, gamma;
 
-  i=0; done=FALSE;
-  while (i<n && done==FALSE) {
+  i=0; done=false;
+  while (i<n && done==false) {
     if (h(i)==0) {
       z(i)=x(i);
       break;
@@ -382,7 +382,7 @@ bool TBox::Intersection(RCRVector x, RCRVector h, RCRVector z) {
       }
       copy(z,tmpV); axpy(-1.0,x,tmpV);  // tmpV=z-x
       if (isect==1 && dot(tmpV,h)>0) {
-	done=TRUE; break;
+	done=true; break;
       }
     }
     i++;
diff --git a/src/algs/stogo/tools.h b/src/algs/stogo/tools.h
index dd8dbafc..29f0563c 100644
--- a/src/algs/stogo/tools.h
+++ b/src/algs/stogo/tools.h
@@ -4,7 +4,7 @@
 #ifndef TOOLS_H
 #define TOOLS_H
 
-#include <float.h>
+#include <cfloat>
 #include <iostream>
 
 #include <algorithm>
@@ -13,13 +13,6 @@
 
 #include "linalg.h"
 
-#ifndef FALSE
-const int FALSE=(1==0); // boolean FALSE
-#endif
-#ifndef FALSE
-const int TRUE=(1==1); // boolean TRUE
-#endif
-
 typedef const class Trial CTrial;
 typedef CTrial& RCTrial;
 typedef CTrial* PCTrial;
@@ -36,11 +29,7 @@ class Trial{
   friend ostream & operator << (ostream &, RCTrial) ;
 };
 
-#if (!defined(_MSC_VER) && (__cplusplus < 201103L)) || (defined(_MSC_VER) && (_MSVC_LANG < 201103L))
-class TrialGT : public unary_function<Trial, bool>
-#else
 class TrialGT
-#endif
 // Predicate for Trial (needed for remove_if)
 {
 public: