Fix #13877 FP constParameterReference when casting to derived class (#8041)

Author: chrchr-github

lib/astutils.cpp

@@ -2943,6 +2943,9 @@ static bool isExpressionChangedAt(const F& getExprTok,
         auto expr = getExprTok();
         if (!expr && !(tok->valueType() && tok->valueType()->pointer == 0 && tok->valueType()->reference == Reference::None))
             aliased = true;
+        if (!aliased && expr && expr->varId() && tok->isCast() && tok->valueType() && tok->valueType()->reference != Reference::None &&
+            Token::Match(tok->astOperand2() ? tok->astOperand2() : tok->astOperand1(), "%varid%", expr->varId()))
+            aliased = true;
         if (!aliased)
             aliased = isAliasOf(tok, expr, &i);
         if (!aliased)

test/testother.cpp

@@ -3982,6 +3982,19 @@ class TestOther : public TestFixture {
               "    t.s->i = 0;\n"
               "}\n");
         ASSERT_EQUALS("", errout_str());
+
+        check("struct B {};\n" // #13877
+              "struct D : B { int i; };\n"
+              "void f(B& b) {\n"
+              "    static_cast<D&>(b).i = 0;\n"
+              "}\n"
+              "void g(B& b) {\n"
+              "    std::cin >> static_cast<D&>(b).i;\n"
+              "}\n"
+              "int h(B& b) {\n"
+              "    return static_cast<const D&>(b).i;\n"
+              "}\n");
+        ASSERT_EQUALS("[test.cpp:9:10]: (style) Parameter 'b' can be declared as reference to const [constParameterReference]\n", errout_str());
     }
 
     void constParameterCallback() {