Fix CID 141172: Add missing move assignment op

Author: dspinellis

src/type.cpp

@@ -61,13 +61,25 @@ Type&
 Type::operator=(const Type& rhs)
 {
 	// The operation sequence handles self-assignment
-	rhs.p->use++;
-	if (--p->use == 0)
+	if (rhs.p) rhs.p->use++;
+	if (p && --p->use == 0)
 		delete p;
 	p = rhs.p;
 	return (*this);
 }
 
+// Move assignment
+Type&
+Type::operator=(Type&& rhs) noexcept {
+	if (this != &rhs) {
+		if (p && --p->use == 0)
+			delete p;
+		p = rhs.p;
+		rhs.p = nullptr;
+	}
+	return *this;
+}
+
 Type
 Type_node::subscript() const
 {

src/type.h

@@ -235,7 +235,7 @@ class Type {
 	Type_node *p;
 public:
 	Type(Type_node *n) : p(n) {}
-	Type() { p = new Tbasic(b_undeclared); }
+	Type() : p(new Tbasic(b_undeclared)) {}
 	// Creation functions
 	friend Type basic(enum e_btype t, enum e_sign s,
 			  enum e_storage_class sc, qualifiers_t);
@@ -259,9 +259,13 @@ class Type {
 	void declare();
 
 	// Manage use count of underlying Type_node
-	Type(const Type& t) : p(t.p) { ++p->use; }	// Copy
-	~Type() { if (--p->use == 0) delete p; }
+	Type(const Type& t) : p(t.p) { if (p) ++p->use; }	// Copy
+	~Type() { if (p && --p->use == 0) delete p; }
 	Type& operator=(const Type& t);
+	// Move constructor
+	Type(Type&& t) noexcept : p(t.p) { t.p = nullptr; }
+	// Move assignment
+	Type& operator=(Type&& rhs) noexcept;
 
 	// Interface to the Type_node functionality
 	Type clone() const 		{ return p->clone(); }