reassign var: better handling of struct members

lib/checkother.cpp

@@ -596,8 +596,8 @@ static void eraseNotLocalArg(std::map<unsigned int, const Token*>& container, co
 
 void CheckOther::checkRedundantAssignment()
 {
-    bool performance = _settings->isEnabled("performance");
+    const bool performance = _settings->isEnabled("performance");
-    bool warning = _settings->isEnabled("warning");
+    const bool warning = _settings->isEnabled("warning");
     if (!warning && !performance)
         return;
 
@@ -637,8 +637,12 @@ void CheckOther::checkRedundantAssignment()
                         initialized.insert(tok->varId());
                 }
 
+                const Token *startToken = tok;
+                while (Token::Match(startToken, "%var%|::|."))
+                    startToken = startToken->previous();
+
                 std::map<unsigned int, const Token*>::iterator it = varAssignments.find(tok->varId());
-                if (tok->next()->isAssignmentOp() && Token::Match(tok->previous(), "[;{}]")) { // Assignment
+                if (tok->next()->isAssignmentOp() && Token::Match(startToken, "[;{}]")) { // Assignment
                     if (it != varAssignments.end()) {
                         bool error = true; // Ensure that variable is not used on right side
                         for (const Token* tok2 = tok->tokAt(2); tok2; tok2 = tok2->next()) {

test/testother.cpp

@@ -5938,6 +5938,38 @@ private:
               "    return bar(x);\n"
               "}");
         ASSERT_EQUALS("", errout.str());
+
+        // struct member..
+        check("struct AB { int a; int b; };\n"
+              "\n"
+              "int f() {\n"
+              "    struct AB ab;\n"
+              "    ab.a = 1;\n"
+              "    ab.a = 2;\n"
+              "    return ab.a;\n"
+              "}");
+        ASSERT_EQUALS("[test.cpp:5] -> [test.cpp:6]: (performance, inconclusive) Variable 'a' is reassigned a value before the old one has been used if variable is no semaphore variable.\n", errout.str());
+
+        check("struct AB { int a; int b; };\n"
+              "\n"
+              "int f() {\n"
+              "    struct AB ab;\n"
+              "    ab.a = 1;\n"
+              "    ab = do_something();\n"
+              "    return ab.a;\n"
+              "}");
+        TODO_ASSERT_EQUALS("error", "", errout.str());
+
+        check("struct AB { int a; int b; };\n"
+              "\n"
+              "int f() {\n"
+              "    struct AB ab;\n"
+              "    ab.a = 1;\n"
+              "    do_something(&ab);\n"
+              "    ab.a = 2;\n"
+              "    return ab.a;\n"
+              "}");
+        ASSERT_EQUALS("", errout.str());
     }
 
     void redundantMemWrite() {