diff --git a/lib/checkclass.cpp b/lib/checkclass.cpp
index ffecf5748..79fe49b2d 100644
--- a/lib/checkclass.cpp
+++ b/lib/checkclass.cpp
@@ -1802,6 +1802,21 @@ bool CheckClass::checkConstFunc(const Scope *scope, const Function *func, bool&
             if (tok1->str() == "this" && tok1->previous()->isAssignmentOp())
                 return (false);
 
+
+            const Token* lhs = tok1->tokAt(-1);
+            if (lhs->str() == "&") {
+                lhs = lhs->previous();
+                if (lhs->type() == Token::eAssignmentOp && lhs->previous()->variable()) {
+                    if (lhs->previous()->variable()->typeStartToken()->strAt(-1) != "const" && lhs->previous()->variable()->isPointer())
+                        return false;
+                }
+            } else {
+                const Variable* v2 = lhs->previous()->variable();
+                if (lhs->type() == Token::eAssignmentOp && v2)
+                    if (!v2->isConst() && v2->isReference() && lhs == v2->nameToken()->next())
+                        return false;
+            }
+
             const Token* jumpBackToken = 0;
             const Token *lastVarTok = tok1;
             const Token *end = tok1;
diff --git a/test/testclass.cpp b/test/testclass.cpp
index 60688f4ab..b8efb9f8d 100644
--- a/test/testclass.cpp
+++ b/test/testclass.cpp
@@ -143,6 +143,7 @@ private:
         TEST_CASE(const60); // ticket #3322
         TEST_CASE(const61); // ticket #5606
         TEST_CASE(const62); // ticket #5701
+        TEST_CASE(const63); // ticket #5983
         TEST_CASE(const_handleDefaultParameters);
         TEST_CASE(const_passThisToMemberOfOtherClass);
         TEST_CASE(assigningPointerToPointerIsNotAConstOperation);
@@ -4842,6 +4843,53 @@ private:
         ASSERT_EQUALS("", errout.str());
     }
 
+    void const63() {
+        checkConst("struct A {\n"
+                   "    std::string s;\n"
+                   "    void clear() {\n"
+                   "         std::string* p = &s;\n"
+                   "         p->clear();\n"
+                   "     }\n"
+                   "};");
+        ASSERT_EQUALS("", errout.str());
+
+        checkConst("struct A {\n"
+                   "    std::string s;\n"
+                   "    void clear() {\n"
+                   "         std::string& r = s;\n"
+                   "         r.clear();\n"
+                   "     }\n"
+                   "};");
+        ASSERT_EQUALS("", errout.str());
+
+        checkConst("struct A {\n"
+                   "    std::string s;\n"
+                   "    void clear() {\n"
+                   "         std::string& r = sth; r = s;\n"
+                   "         r.clear();\n"
+                   "     }\n"
+                   "};");
+        ASSERT_EQUALS("[test.cpp:3]: (style, inconclusive) Technically the member function 'A::clear' can be const.\n", errout.str());
+
+        checkConst("struct A {\n"
+                   "    std::string s;\n"
+                   "    void clear() {\n"
+                   "         const std::string* p = &s;\n"
+                   "         p->somefunction();\n"
+                   "     }\n"
+                   "};");
+        ASSERT_EQUALS("[test.cpp:3]: (style, inconclusive) Technically the member function 'A::clear' can be const.\n", errout.str());
+
+        checkConst("struct A {\n"
+                   "    std::string s;\n"
+                   "    void clear() {\n"
+                   "         const std::string& r = s;\n"
+                   "         r.somefunction();\n"
+                   "     }\n"
+                   "};");
+        ASSERT_EQUALS("[test.cpp:3]: (style, inconclusive) Technically the member function 'A::clear' can be const.\n", errout.str());
+    }
+
     void const_handleDefaultParameters() {
         checkConst("struct Foo {\n"
                    "    void foo1(int i, int j = 0) {\n"