delete more default constructors

reduces code size by 0.1%

src/util/array.h

@@ -26,7 +26,7 @@ public:
     
 private:
 #define ARRAY_SIZE_IDX     -1
-    T * m_data;
+    T * m_data = nullptr;
     void destroy_elements() {
         iterator it = begin();
         iterator e  = end();
@@ -71,7 +71,7 @@ public:
     typedef T * iterator;
     typedef const T * const_iterator;
 
-    array():m_data(nullptr) {}
+    array() = default;
 
     /**
        \brief Store the array in the given chunk of memory (mem).
@@ -193,7 +193,7 @@ public:
 template<typename T>
 class ptr_array : public array<T *, false> {
 public:
-    ptr_array() {}
+    ptr_array() = default;
     ptr_array(void * mem, unsigned sz, T * const * vs):array<T*, false>(mem, sz, vs) {}
     template<typename Allocator>
     ptr_array(Allocator & a, unsigned sz, T * const * vs):array<T*, false>(a, sz, vs) {}
@@ -205,7 +205,7 @@ public:
 template<typename T>
 class sarray : public array<T, false> {
 public:
-    sarray() {}
+    sarray() = default;
     sarray(void * mem, unsigned sz, T const * vs):array<T, false>(mem, sz, vs) {}
     template<typename Allocator>
     sarray(Allocator & a, unsigned sz, T const * vs):array<T, false>(a, sz, vs) {}

src/util/buffer.h

@@ -275,6 +275,6 @@ public:
 template<typename T, unsigned INITIAL_SIZE=16>
 class sbuffer : public buffer<T, false, INITIAL_SIZE> {
 public:
-    sbuffer(): buffer<T, false, INITIAL_SIZE>() {}
+    sbuffer() = default;
     sbuffer(unsigned sz, const T& elem) : buffer<T, false, INITIAL_SIZE>(sz,elem) {}
 };

src/util/inf_rational.h

@@ -65,7 +65,7 @@ class inf_rational {
         return s;
     }
 
-    inf_rational() {}
+    inf_rational() = default;
 
     explicit inf_rational(int n):
         m_first(rational(n)),

src/util/sat_literal.h

@@ -119,7 +119,7 @@ namespace sat {
         literal_set(literal_vector const& v) {
             for (unsigned i = 0; i < v.size(); ++i) insert(v[i]);
         }
-        literal_set() {}
+        literal_set() = default;
         literal_vector to_vector() const {
             literal_vector result;
             for (literal lit : *this) result.push_back(lit);
@@ -146,7 +146,6 @@ namespace sat {
             literal operator*() const { return to_literal(*m_it); }
             iterator& operator++() { ++m_it; return *this; }
             iterator operator++(int) { iterator tmp = *this; ++m_it; return tmp; }
-            bool operator==(iterator const& it) const { return m_it == it.m_it; }
             bool operator!=(iterator const& it) const { return m_it != it.m_it; }
         };
         iterator begin() const { return iterator(m_set.begin()); }

src/util/stacked_value.h

@@ -52,7 +52,7 @@ public:
         }
     }
 
-    stacked_value() {}
+    stacked_value() = default;
     stacked_value(const T& m) {
         m_value = m;
     }