diff --git a/lib/tokenize.cpp b/lib/tokenize.cpp
index 730f3f380..5ec9b4aac 100644
--- a/lib/tokenize.cpp
+++ b/lib/tokenize.cpp
@@ -1703,9 +1703,6 @@ bool Tokenizer::tokenize(std::istream &code,
     // remove unnecessary member qualification..
     removeUnnecessaryQualification();
 
-    // Add std:: in front of std classes, when using namespace std; was given
-    simplifyNamespaceStd();
-
     // remove Microsoft MFC..
     simplifyMicrosoftMFC();
 
@@ -1990,6 +1987,9 @@ bool Tokenizer::tokenize(std::istream &code,
         setVarId();
     }
 
+    // Add std:: in front of std classes, when using namespace std; was given
+    simplifyNamespaceStd();
+
     createLinks2();
 
     // Change initialisation of variable to assignment
@@ -8991,7 +8991,7 @@ void Tokenizer::simplifyNamespaceStd()
         "exception", "bad_exception",
         "logic_error", "domain_error", "invalid_argument_", "length_error", "out_of_rage", "runtime_error", "range_error", "overflow_error", "underflow_error",
         "locale",
-        "cout", "cerr", "clog", "cin",
+        "cout", "cerr", "clog", "cin", "endl",
         "fpos", "streamoff", "streampos", "streamsize"
     };
     static const std::set<std::string> stdTypes(stdTypes_, stdTypes_+sizeof(stdTypes_)/sizeof(*stdTypes_));
@@ -9019,7 +9019,7 @@ void Tokenizer::simplifyNamespaceStd()
             insert = true;
         else if (Token::Match(tok, "%var% <") && !Token::Match(tok->previous(), ".|::") && stdTemplates.find(tok->str()) != stdTemplates.end())
             insert = true;
-        else if (tok->isName() && !Token::Match(tok->next(), "(|<") && !Token::Match(tok->previous(), ".|::") && stdTypes.find(tok->str()) != stdTypes.end())
+        else if (tok->isName() && !tok->varId() && !Token::Match(tok->next(), "(|<") && !Token::Match(tok->previous(), ".|::") && stdTypes.find(tok->str()) != stdTypes.end())
             insert = true;
 
         if (insert) {
diff --git a/test/testtokenize.cpp b/test/testtokenize.cpp
index 49e148a84..8eb78f075 100644
--- a/test/testtokenize.cpp
+++ b/test/testtokenize.cpp
@@ -7123,6 +7123,29 @@ private:
         static const char code10[] = "std::tr1::function <void(int)> f;";
         ASSERT_EQUALS("std :: tr1 :: function < void ( int ) > f ;", tokenizeAndStringify(code10, false, true, Settings::Unspecified, "test.cpp", false));
         ASSERT_EQUALS("std :: function < void ( int ) > f ;", tokenizeAndStringify(code10, false, true, Settings::Unspecified, "test.cpp", true));
+
+        // #4042 (Do not add 'std ::' to variables)
+        static const char code11[] = "using namespace std;\n"
+                                     "const char * string = \"Hi\";";
+        ASSERT_EQUALS("const char * string ; string = \"Hi\" ;", tokenizeAndStringify(code11, false));
+
+        static const char code12[] = "using namespace std;\n"
+                                     "string f(const char * string) {\n"
+                                     "    cout << string << endl;\n"
+                                     "    return string;\n"
+                                     "}";
+        static const char expected12[] = "std :: string f ( const char * string ) {\n"
+                                         "std :: cout << string << std :: endl ;\n"
+                                         "return string ;\n"
+                                         "}";
+        ASSERT_EQUALS(expected12, tokenizeAndStringify(code12, false));
+
+        static const char code13[] = "using namespace std;\n"
+                                     "try { }\n"
+                                     "catch(std::exception &exception) { }";
+        static const char expected13[] = "try { }\n"
+                                         "catch ( std :: exception & exception ) { }";
+        ASSERT_EQUALS(expected13, tokenizeAndStringify(code13, false));
     }
 
     void microsoftMFC() {