Merge pull request #621 from andreasfertig/fixIssue620

Fixed #620: Do not show move construction for NRVO return.

Author: andreasfertig

CodeGenerator.cpp

@@ -4141,7 +4141,11 @@ void CodeGenerator::InsertArg(const ReturnStmt* stmt)
             mOutputFormatHelper.Append(' ');
 
             if(not temporaryFinder.Found()) {
-                InsertArg(retVal);
+                if(const auto* nrvoVD = stmt->getNRVOCandidate()) {
+                    mOutputFormatHelper.Append(GetName(*nrvoVD));
+                } else {
+                    InsertArg(retVal);
+                }
             } else {
                 mOutputFormatHelper.Append(temporaryFinder.Name());
             }

tests/Class2Test.expect

@@ -33,7 +33,7 @@ class Test
   {
     Test tmp = Test(*this) /* NRVO variable */;
     this->operator++();
-    return Test(static_cast<Test &&>(tmp).operator int());
+    return tmp;
   }
 
   inline Test & operator+=(const Test & rhs)

tests/ClassOperatorHandler2Test.expect

@@ -30,7 +30,7 @@ class Foo
     printf("  ======\n");
     ++this->mX;
     printf("  ++++++\n");
-    return Foo(static_cast<Foo &&>(old));
+    return old;
   }
 
   inline Foo & operator++()
@@ -45,7 +45,7 @@ class Foo
     printf("  ======\n");
     --this->mX;
     printf("  ++++++\n");
-    return Foo(static_cast<Foo &&>(old));
+    return old;
   }
 
   inline Foo & operator--()

tests/ClassOperatorHandler9Test.expect

@@ -83,7 +83,7 @@ MyVector<int> operator+(const MyVector<int> & a, const MyVector<int> & b)
     result.operator[](s) = (a.operator[](s) + b.operator[](s));
   }
 
-  return MyVector<int>(static_cast<MyVector<int> &&>(result));
+  return result;
 }
 
 template<typename T>
@@ -107,7 +107,7 @@ MyVector<int> operator*<int>(const MyVector<int> & a, const MyVector<int> & b)
     result.operator[](s) = (a.operator[](s) + b.operator[](s));
   }
 
-  return MyVector<int>(static_cast<MyVector<int> &&>(result));
+  return result;
 }
 #endif
 
@@ -119,7 +119,7 @@ MyVector<int> Foo(const MyVector<int> & a, const MyVector<int> & b)
     result.operator[](s) = (a.operator[](s) + b.operator[](s));
   }
 
-  return MyVector<int>(static_cast<MyVector<int> &&>(result));
+  return result;
 }
 
 int main()

tests/ClassOperatorHandlerTest.expect

@@ -17,7 +17,7 @@ class Test
   {
     Test tmp = Test{*this} /* NRVO variable */;
     this->mX++;
-    return Test(static_cast<Test &&>(tmp));
+    return tmp;
   }
 
   inline Test operator--()
@@ -30,7 +30,7 @@ class Test
   {
     Test tmp = Test{*this} /* NRVO variable */;
     this->mX--;
-    return Test(static_cast<Test &&>(tmp));
+    return tmp;
   }
 
   inline Test & operator+=(const Test & rhs)

tests/ClassTest.expect

@@ -28,7 +28,7 @@ class Test
   {
     Test tmp = Test(*this) /* NRVO variable */;
     this->operator++();
-    return Test(static_cast<Test &&>(tmp).operator int());
+    return tmp;
   }
 
   inline Test & operator+=(const Test & rhs)

tests/EduLifeTimeTest10.expect

@@ -31,7 +31,7 @@ Vector createStrings2()
   const char *const __temporary19_58[6] = {"This", "is", "a", "vector", "of", "strings"};
   Vector v = Vector{std::initializer_list<const char *>{__temporary19_58, 6}} /* NRVO variable */;
   /* __temporary19_58 // lifetime ends here */
-  return Vector(static_cast<Vector &&>(v));
+  return v;
   /* v // lifetime ends here */
 }
 

tests/Issue620.cpp

@@ -0,0 +1,20 @@
+#include <cstdio>
+#include <utility>
+
+class C {
+public:
+    C() { printf("default constructor\n"); }
+    ~C() { printf("destructor\n"); }
+    //C(const C&) { printf("copy constructor\n"); }
+    C(C&&) { printf("move constructor\n"); }
+    //C& operator=(const C&) { printf("copy assignment\n"); return *this; }
+    C& operator=(C&&) { printf("move assignment\n"); return *this; }
+private:
+    int x;
+};
+
+C f() {
+  C c;
+  return c;
+}
+

tests/Issue620.expect

@@ -0,0 +1,42 @@
+#include <cstdio>
+#include <utility>
+
+class C
+{
+  
+  public: 
+  inline C()
+  {
+    printf("default constructor\n");
+  }
+  
+  inline ~C() noexcept
+  {
+    printf("destructor\n");
+  }
+  
+  inline C(C &&)
+  {
+    printf("move constructor\n");
+  }
+  
+  inline C & operator=(C &&)
+  {
+    printf("move assignment\n");
+    return *this;
+  }
+  
+  
+  private: 
+  int x;
+  public: 
+  // inline constexpr C(const C &) /* noexcept */ = delete;
+  // inline C & operator=(const C &) /* noexcept */ = delete;
+};
+
+
+C f()
+{
+  C c = C() /* NRVO variable */;
+  return c;
+}

tests/NRVOHandlerTest.expect

@@ -14,14 +14,14 @@ struct C
 C f()
 {
   C namedC /* NRVO variable */;
-  return C(static_cast<const C &&>(namedC));
+  return namedC;
 }
 
 C f2()
 {
   C namedC;
   C namedC2 = C{namedC} /* NRVO variable */;
-  return C(static_cast<const C &&>(namedC2));
+  return namedC2;
 }
 
 int main()