Fix #11616 false negative: functionConst (#4887)

lib/checkclass.cpp

@@ -2328,7 +2328,7 @@ bool CheckClass::checkConstFunc(const Scope *scope, const Function *func, bool&
                 tok = tok->link();
             else if ((tok->isName() && isMemberVar(scope, tok)) || (tok->isUnaryOp("&") && (tok = tok->astOperand1()) && isMemberVar(scope, tok))) {
                 const Variable* var = tok->variable();
-                if ((!var || !var->isMutable()) && mayModifyArgs)
+                if ((!var || (!var->isMutable() && !var->isConst())) && mayModifyArgs)
                     return false; // TODO: Only bailout if function takes argument as non-const reference
             }
         }

lib/checkleakautovar.cpp

@@ -141,7 +141,7 @@ void VarInfo::possibleUsageAll(const std::string &functionName)
 }
 
 
-void CheckLeakAutoVar::leakError(const Token *tok, const std::string &varname, int type)
+void CheckLeakAutoVar::leakError(const Token *tok, const std::string &varname, int type) const
 {
     const CheckMemoryLeak checkmemleak(mTokenizer, mErrorLogger, mSettings);
     if (Library::isresource(type))
@@ -150,14 +150,14 @@ void CheckLeakAutoVar::leakError(const Token *tok, const std::string &varname, i
         checkmemleak.memleakError(tok, varname);
 }
 
-void CheckLeakAutoVar::mismatchError(const Token *deallocTok, const Token *allocTok, const std::string &varname)
+void CheckLeakAutoVar::mismatchError(const Token *deallocTok, const Token *allocTok, const std::string &varname) const
 {
     const CheckMemoryLeak c(mTokenizer, mErrorLogger, mSettings);
     const std::list<const Token *> callstack = { allocTok, deallocTok };
     c.mismatchAllocDealloc(callstack, varname);
 }
 
-void CheckLeakAutoVar::deallocUseError(const Token *tok, const std::string &varname)
+void CheckLeakAutoVar::deallocUseError(const Token *tok, const std::string &varname) const
 {
     const CheckMemoryLeak c(mTokenizer, mErrorLogger, mSettings);
     c.deallocuseError(tok, varname);
@@ -842,7 +842,7 @@ const Token * CheckLeakAutoVar::checkTokenInsideExpression(const Token * const t
 }
 
 
-void CheckLeakAutoVar::changeAllocStatusIfRealloc(std::map<int, VarInfo::AllocInfo> &alloctype, const Token *fTok, const Token *retTok)
+void CheckLeakAutoVar::changeAllocStatusIfRealloc(std::map<int, VarInfo::AllocInfo> &alloctype, const Token *fTok, const Token *retTok) const
 {
     const Library::AllocFunc* f = mSettings->library.getReallocFuncInfo(fTok);
     if (f && f->arg == -1 && f->reallocArg > 0 && f->reallocArg <= numberOfArguments(fTok)) {

lib/checkleakautovar.h

@@ -144,7 +144,7 @@ private:
     void changeAllocStatus(VarInfo &varInfo, const VarInfo::AllocInfo& allocation, const Token* tok, const Token* arg);
 
     /** update allocation status if reallocation function */
-    void changeAllocStatusIfRealloc(std::map<int, VarInfo::AllocInfo> &alloctype, const Token *fTok, const Token *retTok);
+    void changeAllocStatusIfRealloc(std::map<int, VarInfo::AllocInfo> &alloctype, const Token *fTok, const Token *retTok) const;
 
     /** return. either "return" or end of variable scope is seen */
     void ret(const Token *tok, VarInfo &varInfo, const bool isEndOfScope = false);
@@ -152,9 +152,9 @@ private:
     /** if variable is allocated then there is a leak */
     void leakIfAllocated(const Token *vartok, const VarInfo &varInfo);
 
-    void leakError(const Token* tok, const std::string &varname, int type);
+    void leakError(const Token* tok, const std::string &varname, int type) const;
-    void mismatchError(const Token* deallocTok, const Token* allocTok, const std::string &varname);
+    void mismatchError(const Token* deallocTok, const Token* allocTok, const std::string &varname) const;
-    void deallocUseError(const Token *tok, const std::string &varname);
+    void deallocUseError(const Token *tok, const std::string &varname) const;
     void deallocReturnError(const Token *tok, const Token *deallocTok, const std::string &varname);
     void doubleFreeError(const Token *tok, const Token *prevFreeTok, const std::string &varname, int type);
 

lib/symboldatabase.h

@@ -1454,7 +1454,7 @@ public:
     nonneg int sizeOfType(const Token *type) const;
 
     /** Set array dimensions when valueflow analysis is completed */
-    void setArrayDimensionsUsingValueFlow();
+    void setArrayDimensionsUsingValueFlow(); // cppcheck-suppress functionConst // has side effects
 
     void clangSetVariables(const std::vector<const Variable *> &variableList);
     void createSymbolDatabaseExprIds();

test/testclass.cpp

@@ -198,6 +198,7 @@ private:
         TEST_CASE(const82); // ticket #11513
         TEST_CASE(const83);
         TEST_CASE(const84);
+        TEST_CASE(const85);
 
         TEST_CASE(const_handleDefaultParameters);
         TEST_CASE(const_passThisToMemberOfOtherClass);
@@ -6361,7 +6362,27 @@ private:
         ASSERT_EQUALS("", errout.str());
     }
 
-    void const84() { // #11618
+    void const84() {
+        checkConst("class S {};\n" // #11616
+                   "struct T {\n"
+                   "    T(const S*);\n"
+                   "    T(const S&);\n"
+                   "};\n"
+                   "struct C {\n"
+                   "    const S s;\n"
+                   "    void f1() {\n"
+                   "        T t(&s);\n"
+                   "    }\n"
+                   "    void f2() {\n"
+                   "        T t(s);\n"
+                   "    }\n"
+                   "};\n");
+        ASSERT_EQUALS("[test.cpp:8]: (style, inconclusive) Technically the member function 'C::f1' can be const.\n"
+                      "[test.cpp:11]: (style, inconclusive) Technically the member function 'C::f2' can be const.\n",
+                      errout.str());
+    }
+
+    void const85() { // #11618
         checkConst("struct S {\n"
                    "    int a[2], b[2];\n"
                    "    void f() { f(a, b); }\n"