Fix representative issue in bench which result in too much computation

being removed by the compiler.

bench/bench-stl.cpp

@@ -17,6 +17,8 @@
 
 using namespace std;
 
+unsigned long g_result;
+
 static unsigned long long
 cputime (void)
 {
@@ -61,6 +63,7 @@ static void test_list(size_t n)
   for (list<unsigned int>::const_iterator ci1 = a1.begin(), ci2 = a2.begin (); ci1 != a1.end(); ++ci1, ++ci2) {
     s += *ci1 * *ci2;
   }
+  g_result = s;
 }
 
 /********************************************************************************************/
@@ -77,6 +80,7 @@ static void test_array(size_t n)
   for(unsigned long i = 0; i < n; i++) {
     s += a1[i] * a2[i];
   }
+  g_result = s;
 }
 
 /********************************************************************************************/
@@ -96,6 +100,7 @@ static void test_rbtree(size_t n)
     if (it != tree.end())
       s += *it;
   }
+  g_result = s;
 }
 
 /********************************************************************************************/
@@ -116,6 +121,7 @@ test_dict1(unsigned long  n)
     if (it != dict.end())
       s += it->second;
   }
+  g_result = s;
 }
 
 /********************************************************************************************/
@@ -136,6 +142,7 @@ test_dict2(unsigned long  n)
     if (it != dict.end())
       s += it->second;
   }
+  g_result = s;
 }
 
 /********************************************************************************************/
@@ -178,7 +185,8 @@ test_dict_big(unsigned long  n)
     unordered_map<char_array_s, char_array_s>::iterator it = dict.find(s1);
     if (it != dict.end())
       s ++;
-      }
+  }
+  g_result = s;
 }
 
 /********************************************************************************************/