Fixed #1612 (false positive: The function can be const)

lib/tokenize.cpp

@@ -2249,6 +2249,12 @@ void Tokenizer::setVarId()
         if (Token::Match(tok, "class|struct %type% :|{|;"))
             continue;
 
+        if (Token::Match(tok, "using namespace %type% ;"))
+        {
+            tok = tok->next();
+            continue;
+        }
+
         if (Token::Match(tok, "else|return|typedef|delete|sizeof"))
             continue;
 

test/testclass.cpp

@@ -113,6 +113,7 @@ private:
         TEST_CASE(const16); // ticket #1551
         TEST_CASE(const17); // ticket #1552
         TEST_CASE(const18); // ticket #1563
+        TEST_CASE(const19); // ticket #1612
         TEST_CASE(constoperator1);  // operator< can often be const
         TEST_CASE(constoperator2);	// operator<<
         TEST_CASE(constincdec);     // increment/decrement => non-const
@@ -3217,6 +3218,19 @@ private:
         ASSERT_EQUALS("", errout.str());
     }
 
+    void const19()
+    {
+        // ticket #1612
+        checkConst("using namespace std;\n"
+                   "class Fred {\n"
+                   "private:\n"
+                   "    std::string s;\n"
+                   "public:\n"
+                   "    void set(std::string ss) { s = ss; }\n"
+                   "};\n");
+        ASSERT_EQUALS("", errout.str());
+    }
+
     // increment/decrement => not const
     void constincdec()
     {