diff --git a/lib/checkclass.cpp b/lib/checkclass.cpp
index 52af58b6c..aeb67a4e4 100644
--- a/lib/checkclass.cpp
+++ b/lib/checkclass.cpp
@@ -924,7 +924,12 @@ void CheckClass::operatorEqRetRefThis()
                             // check for return of reference to this
                             if (tok1->str() == "return")
                             {
+                                std::string cast("( " + name->str() + " & )");
+                                if (Token::Match(tok1->next(), cast.c_str()))
+                                    tok1 = tok1->tokAt(4);
+
                                 if (!(Token::Match(tok1->tokAt(1), "(| * this ;|=") ||
+                                      Token::Match(tok1->tokAt(1), "(| * this +=") ||
                                       Token::Match(tok1->tokAt(1), "operator = (")))
                                     operatorEqRetRefThisError(tok);
                             }
@@ -976,7 +981,12 @@ void CheckClass::operatorEqRetRefThis()
                             // check for return of reference to this
                             if (tok1->str() == "return")
                             {
+                                std::string cast("( " + name->str() + " & )");
+                                if (Token::Match(tok1->next(), cast.c_str()))
+                                    tok1 = tok1->tokAt(4);
+
                                 if (!(Token::Match(tok1->tokAt(1), "(| * this ;|=") ||
+                                      Token::Match(tok1->tokAt(1), "(| * this +=") ||
                                       Token::Match(tok1->tokAt(1), "operator = (")))
                                     operatorEqRetRefThisError(tok);
                             }
diff --git a/test/testclass.cpp b/test/testclass.cpp
index fbaa15053..5a46e576c 100644
--- a/test/testclass.cpp
+++ b/test/testclass.cpp
@@ -72,6 +72,7 @@ private:
         TEST_CASE(operatorEqRetRefThis1);
         TEST_CASE(operatorEqRetRefThis2); // ticket #1323
         TEST_CASE(operatorEqRetRefThis3); // ticket #1405
+        TEST_CASE(operatorEqRetRefThis4); // ticket #1451
         TEST_CASE(operatorEqToSelf1);   // single class
         TEST_CASE(operatorEqToSelf2);   // nested class
         TEST_CASE(operatorEqToSelf3);   // multiple inheritance
@@ -310,6 +311,17 @@ private:
         ASSERT_EQUALS("", errout.str());
     }
 
+    void operatorEqRetRefThis4()
+    {
+        // ticket # 1451
+        checkOpertorEqRetRefThis(
+            "P& P::operator = (const P& pc)\n"
+            "{\n"
+            "  return (P&)(*this += pc);\n"
+            "}");
+        ASSERT_EQUALS("", errout.str());
+    }
+
     // Check that operator Equal checks for assignment to self
     void checkOpertorEqToSelf(const char code[])
     {