Fix #15037 FN redundantInitialization with cast (#8854)

Author: chrchr-github

lib/checkother.cpp

@@ -633,7 +633,7 @@ void CheckOtherImpl::checkRedundantAssignment()
                         if (Token::Match(rhs, ":: %name%") && rhs->hasKnownIntValue())
                             return ChildrenToVisit::none;
                         if (rhs->isCast())
-                            return ChildrenToVisit::op2;
+                            return rhs->astOperand2() ? ChildrenToVisit::op2 : ChildrenToVisit::op1;
                         trivial = false;
                         return ChildrenToVisit::done;
                     });

test/testother.cpp

@@ -11502,6 +11502,23 @@ class TestOther : public TestFixture {
               "    return i;\n"
               "}\n");
         ASSERT_EQUALS("", errout_str());
+
+        check("int f(char c) {\n" // #15037
+              "	   int i = (int)c;\n"
+              "	   i = 3;\n"
+              "	   return i;\n"
+              "}\n"
+              "int g(char c) {\n"
+              "     int i = static_cast<int>(c);\n"
+              "     i = 3;\n"
+              "     return i;\n"
+              "}\n");
+        ASSERT_EQUALS("[test.cpp:3:7]: style: Redundant initialization for 'i'. The initialized value is overwritten before it is read. [redundantInitialization]\n"
+                      "[test.cpp:2:11]: note: i is initialized\n"
+                      "[test.cpp:3:7]: note: i is overwritten\n"
+                      "[test.cpp:8:8]: style: Redundant initialization for 'i'. The initialized value is overwritten before it is read. [redundantInitialization]\n"
+                      "[test.cpp:7:12]: note: i is initialized\n"
+                      "[test.cpp:8:8]: note: i is overwritten\n", errout_str());
     }
 
     // cppcheck-suppress unusedPrivateFunction