Fix #11654 FN functionConst if only non-const member usage is call to itself (#5092)

* Fix #11654 FN functionConst if only non-const member usage is call to itself

* Format

* Add const

lib/checkclass.cpp

@@ -741,7 +741,7 @@ bool CheckClass::isBaseClassMutableMemberFunc(const Token *tok, const Scope *sco
     return false;
 }
 
-void CheckClass::initializeVarList(const Function &func, std::list<const Function *> &callstack, const Scope *scope, std::vector<Usage> &usage)
+void CheckClass::initializeVarList(const Function &func, std::list<const Function *> &callstack, const Scope *scope, std::vector<Usage> &usage) const
 {
     if (!func.functionScope)
         return;
@@ -2310,9 +2310,9 @@ bool CheckClass::checkConstFunc(const Scope *scope, const Function *func, bool&
         return nullptr;
     };
 
-    auto checkFuncCall = [this, &memberAccessed](const Token* funcTok, const Scope* scope) {
+    auto checkFuncCall = [this, &memberAccessed](const Token* funcTok, const Scope* scope, const Function* func) {
         if (isMemberFunc(scope, funcTok) && (funcTok->strAt(-1) != "." || Token::simpleMatch(funcTok->tokAt(-2), "this ."))) {
-            if (!isConstMemberFunc(scope, funcTok))
+            if (!isConstMemberFunc(scope, funcTok) && func != funcTok->function())
                 return false;
             memberAccessed = true;
         }
@@ -2490,7 +2490,7 @@ bool CheckClass::checkConstFunc(const Scope *scope, const Function *func, bool&
                 return false;
 
             tok1 = jumpBackToken?jumpBackToken:end; // Jump back to first [ to check inside, or jump to end of expression
-            if (tok1 == end && Token::Match(end->previous(), ". %name% ( !!)") && !checkFuncCall(tok1, scope)) // function call on member
+            if (tok1 == end && Token::Match(end->previous(), ". %name% ( !!)") && !checkFuncCall(tok1, scope, func)) // function call on member
                 return false;
         }
 
@@ -2509,7 +2509,7 @@ bool CheckClass::checkConstFunc(const Scope *scope, const Function *func, bool&
 
         // function/constructor call, return init list
         else if (const Token* funcTok = getFuncTok(tok1)) {
-            if (!checkFuncCall(funcTok, scope))
+            if (!checkFuncCall(funcTok, scope, func))
                 return false;
         } else if (Token::simpleMatch(tok1, "> (") && (!tok1->link() || !Token::Match(tok1->link()->previous(), "static_cast|const_cast|dynamic_cast|reinterpret_cast"))) {
             return false;

lib/checkclass.h

@@ -392,7 +392,7 @@ private:
      * @param scope pointer to variable Scope
      * @param usage reference to usage vector
      */
-    void initializeVarList(const Function &func, std::list<const Function *> &callstack, const Scope *scope, std::vector<Usage> &usage);
+    void initializeVarList(const Function &func, std::list<const Function *> &callstack, const Scope *scope, std::vector<Usage> &usage) const;
 
     /**
      * @brief gives a list of tokens where virtual functions are called directly or indirectly

lib/checkuninitvar.cpp

@@ -827,7 +827,7 @@ bool CheckUninitVar::checkScopeForVariable(const Token *tok, const Variable& var
     return false;
 }
 
-const Token *CheckUninitVar::checkExpr(const Token *tok, const Variable& var, const Alloc alloc, bool known, bool *bailout)
+const Token* CheckUninitVar::checkExpr(const Token* tok, const Variable& var, const Alloc alloc, bool known, bool* bailout) const
 {
     if (!tok)
         return nullptr;

lib/checkuninitvar.h

@@ -82,7 +82,7 @@ public:
     void checkStruct(const Token *tok, const Variable &structvar);
     enum Alloc { NO_ALLOC, NO_CTOR_CALL, CTOR_CALL, ARRAY };
     bool checkScopeForVariable(const Token *tok, const Variable& var, bool* const possibleInit, bool* const noreturn, Alloc* const alloc, const std::string &membervar, std::map<nonneg int, VariableValue> variableValue);
-    const Token *checkExpr(const Token *tok, const Variable& var, const Alloc alloc, bool known, bool *bailout=nullptr);
+    const Token* checkExpr(const Token* tok, const Variable& var, const Alloc alloc, bool known, bool* bailout = nullptr) const;
     bool checkIfForWhileHead(const Token *startparentheses, const Variable& var, bool suppressErrors, bool isuninit, Alloc alloc, const std::string &membervar);
     bool checkLoopBody(const Token *tok, const Variable& var, const Alloc alloc, const std::string &membervar, const bool suppressErrors);
     const Token* checkLoopBodyRecursive(const Token *start, const Variable& var, const Alloc alloc, const std::string &membervar, bool &bailout) const;

lib/tokenize.h

@@ -195,7 +195,7 @@ public:
      * \param only_k_r_fpar Only simplify K&R function parameters
      */
     void simplifyVarDecl(const bool only_k_r_fpar);
-    void simplifyVarDecl(Token * tokBegin, const Token * const tokEnd, const bool only_k_r_fpar);
+    void simplifyVarDecl(Token * tokBegin, const Token * const tokEnd, const bool only_k_r_fpar); // cppcheck-suppress functionConst // has side effects
 
     /**
      * Simplify variable initialization

test/testclass.cpp

@@ -198,6 +198,7 @@ private:
         TEST_CASE(const85);
         TEST_CASE(const86);
         TEST_CASE(const87);
+        TEST_CASE(const89);
 
         TEST_CASE(const_handleDefaultParameters);
         TEST_CASE(const_passThisToMemberOfOtherClass);
@@ -6414,6 +6415,29 @@ private:
                       errout.str());
     }
 
+    void const89() { // #11654
+        checkConst("struct S {\n"
+                   "    void f(bool b);\n"
+                   "    int i;\n"
+                   "};\n"
+                   "void S::f(bool b) {\n"
+                   "    if (i && b)\n"
+                   "        f(false);\n"
+                   "}\n");
+        ASSERT_EQUALS("[test.cpp:5] -> [test.cpp:2]: (style, inconclusive) Technically the member function 'S::f' can be const.\n", errout.str());
+
+        checkConst("struct S {\n"
+                   "    void f(int& r);\n"
+                   "    int i;\n"
+                   "};\n"
+                   "void S::f(int& r) {\n"
+                   "    r = 0;\n"
+                   "    if (i)\n"
+                   "        f(i);\n"
+                   "}\n");
+        ASSERT_EQUALS("", errout.str());
+    }
+
     void const_handleDefaultParameters() {
         checkConst("struct Foo {\n"
                    "    void foo1(int i, int j = 0) {\n"