diff --git a/lib/checkbufferoverrun.cpp b/lib/checkbufferoverrun.cpp
index 76a075e88..d5fa5b49a 100644
--- a/lib/checkbufferoverrun.cpp
+++ b/lib/checkbufferoverrun.cpp
@@ -79,7 +79,7 @@ void CheckBufferOverrun::arrayIndexOutOfBoundsError(const Token *tok, const Arra
         errmsg << " out of bounds.";
     }
 
-    const Token *condition = 0;
+    const Token *condition = nullptr;
     for (unsigned int i = 0; i < index.size(); ++i) {
         if (condition == nullptr)
             condition = index[i].condition;
@@ -428,7 +428,7 @@ static bool for3(const Token * const tok,
                  std::string &max_value,
                  const bool maxMinFlipped)
 {
-    assert(tok != 0);
+    assert(tok != nullptr);
     if (Token::Match(tok, "%varid%  = %num% + %varid% )", varid)) {
         if (!for_maxvalue(tok->tokAt(2), min_value, max_value))
             return false;
@@ -1498,7 +1498,7 @@ void CheckBufferOverrun::checkGlobalAndLocalVariable()
             std::string type;
 
             // varid : The variable id for the array
-            const Variable *var = 0;
+            const Variable *var = nullptr;
 
             // nextTok : number of tokens used in variable declaration - used to skip to next statement.
             int nextTok = 0;
diff --git a/lib/checkclass.cpp b/lib/checkclass.cpp
index 9b16ea6b1..4fb84c261 100644
--- a/lib/checkclass.cpp
+++ b/lib/checkclass.cpp
@@ -917,8 +917,8 @@ void CheckClass::checkMemset()
                     continue;
 
 
-                const Token *typeTok = 0;
-                const Scope *type = 0;
+                const Token *typeTok = nullptr;
+                const Scope *type = nullptr;
                 if (Token::Match(arg3, "sizeof ( %type% ) )"))
                     typeTok = arg3->tokAt(2);
                 else if (Token::Match(arg3, "sizeof ( %type% :: %type% ) )"))
@@ -1252,7 +1252,7 @@ bool CheckClass::hasAllocation(const Function *func, const Scope* scope)
             return true;
 
         // check for deallocating memory
-        const Token *var = 0;
+        const Token *var = nullptr;
         if (Token::Match(tok, "free ( %var%"))
             var = tok->tokAt(2);
         else if (Token::Match(tok, "delete [ ] %var%"))
@@ -1395,7 +1395,7 @@ void CheckClass::virtualDestructor()
 
                 // Find the destructor declaration for the base class.
                 const Function *base_destructor = derivedFromScope->getDestructor();
-                const Token *base = 0;
+                const Token *base = nullptr;
                 if (base_destructor)
                     base = base_destructor->token;
 
diff --git a/lib/checkexceptionsafety.cpp b/lib/checkexceptionsafety.cpp
index 6da9e687d..321fbb4e4 100644
--- a/lib/checkexceptionsafety.cpp
+++ b/lib/checkexceptionsafety.cpp
@@ -98,7 +98,7 @@ void CheckExceptionSafety::deallocThrow()
             const unsigned int varid(tok->varId());
 
             // Token where throw occurs
-            const Token *ThrowToken = 0;
+            const Token *ThrowToken = nullptr;
 
             // is there a throw after the deallocation?
             const Token* const end2 = tok->scope()->classEnd;
diff --git a/lib/checkio.cpp b/lib/checkio.cpp
index 9d6638e77..146a58886 100644
--- a/lib/checkio.cpp
+++ b/lib/checkio.cpp
@@ -318,7 +318,7 @@ void CheckIO::invalidScanf()
     for (std::size_t j = 0; j < functions; ++j) {
         const Scope * scope = symbolDatabase->functionScopes[j];
         for (const Token *tok = scope->classStart->next(); tok != scope->classEnd; tok = tok->next()) {
-            const Token *formatToken = 0;
+            const Token *formatToken = nullptr;
             if (Token::Match(tok, "scanf|vscanf ( %str% ,"))
                 formatToken = tok->tokAt(2);
             else if (Token::Match(tok, "sscanf|vsscanf|fscanf|vfscanf (")) {
@@ -424,7 +424,7 @@ static bool findFormat(unsigned int arg, const Token *firstArg,
                   argTok->variable()->dimensionKnown(0) &&
                   argTok->variable()->dimension(0) != 0)))) {
         *formatArgTok = argTok->nextArgument();
-        *formatStringTok = 0;
+        *formatStringTok = nullptr;
         if (argTok->variable()) {
             const Token *varTok = argTok->variable()->nameToken();
             if (Token::Match(varTok, "%var% ; %var% = %str% ;") &&
@@ -1330,7 +1330,7 @@ CheckIO::ArgumentInfo::ArgumentInfo(const Token * tok, const Settings *settings)
                 tok = tok->tokAt(2);
             if (!tok || !(tok->type() == Token::eVariable || tok->type() == Token::eFunction))
                 return;
-            const Token *varTok = 0;
+            const Token *varTok = nullptr;
             const Token *tok1 = tok->next();
             for (; tok1; tok1 = tok1->next()) {
                 if (tok1->str() == "," || tok1->str() == ")") {
diff --git a/lib/checkmemoryleak.cpp b/lib/checkmemoryleak.cpp
index 36ff92333..3eda73a0f 100644
--- a/lib/checkmemoryleak.cpp
+++ b/lib/checkmemoryleak.cpp
@@ -629,7 +629,7 @@ const char * CheckMemoryLeakInFunction::call_func(const Token *tok, std::list<co
 
         Token *ftok = getcode(func->functionScope->classStart->next(), callstack, 0, alloctype, dealloctype, false, 1);
         simplifycode(ftok);
-        const char *ret = 0;
+        const char *ret = nullptr;
         if (Token::simpleMatch(ftok, "; alloc ; }"))
             ret = "alloc";
         else if (Token::simpleMatch(ftok, "; dealloc ; }"))
@@ -688,7 +688,7 @@ const char * CheckMemoryLeakInFunction::call_func(const Token *tok, std::list<co
             while (func_ && func_->str() == ";")
                 func_ = func_->next();
 
-            const char *ret = 0;
+            const char *ret = nullptr;
             /** @todo handle "goto" */
             if (Token::findsimplematch(func_, "dealloc"))
                 ret = "dealloc";
@@ -782,7 +782,7 @@ Token *CheckMemoryLeakInFunction::getcode(const Token *tok, std::list<const Toke
                 ;
 
             else {
-                const Token *skipToToken = 0;
+                const Token *skipToToken = nullptr;
 
                 // scan statement for interesting keywords / varid
                 for (tok2 = tok->next(); tok2; tok2 = tok2->next()) {
diff --git a/lib/checknullpointer.cpp b/lib/checknullpointer.cpp
index 7de265021..1f5a84d50 100644
--- a/lib/checknullpointer.cpp
+++ b/lib/checknullpointer.cpp
@@ -629,8 +629,8 @@ void CheckNullPointer::nullPointerByCheckAndDeRef()
             continue;
 
         // vartok : token for the variable
-        const Token *vartok = 0;
-        const Token *checkConditionStart = 0;
+        const Token *vartok = nullptr;
+        const Token *checkConditionStart = nullptr;
         if (Token::Match(tok, "( ! %var% )|&&")) {
             vartok = tok->tokAt(2);
             checkConditionStart = vartok->next();
@@ -892,7 +892,7 @@ void CheckNullPointer::nullConstantDereference()
                 }
             }
 
-            const Variable *ovar = 0;
+            const Variable *ovar = nullptr;
             if (Token::Match(tok, "0 ==|!= %var% !!."))
                 ovar = tok->tokAt(2)->variable();
             else if (Token::Match(tok, "%var% ==|!= 0"))
diff --git a/lib/checkother.cpp b/lib/checkother.cpp
index e22f0e72b..addf83d7f 100644
--- a/lib/checkother.cpp
+++ b/lib/checkother.cpp
@@ -514,7 +514,7 @@ void CheckOther::invalidPointerCast()
                 continue;
 
             // Find casted variable
-            const Variable *var = 0;
+            const Variable *var = nullptr;
             bool allocation = false;
             bool ref = false;
             if (Token::Match(nextTok, "new %type%"))
diff --git a/lib/checksizeof.cpp b/lib/checksizeof.cpp
index a2ac2f761..c50014cc5 100644
--- a/lib/checksizeof.cpp
+++ b/lib/checksizeof.cpp
@@ -113,7 +113,7 @@ void CheckSizeof::checkSizeofForPointerSize()
         for (const Token* tok = scope->classStart; tok != scope->classEnd; tok = tok->next()) {
             const Token *tokVar;
             const Token *variable;
-            const Token *variable2 = 0;
+            const Token *variable2 = nullptr;
 
             // Find any function that may use sizeof on a pointer
             // Once leaving those tests, it is mandatory to have:
diff --git a/lib/checkstl.cpp b/lib/checkstl.cpp
index 7aec06541..e96799bdd 100644
--- a/lib/checkstl.cpp
+++ b/lib/checkstl.cpp
@@ -655,7 +655,7 @@ void CheckStl::pushback()
                     if (varId == 0)
                         continue;
 
-                    const Token *pushbackTok = 0;
+                    const Token *pushbackTok = nullptr;
 
                     // Count { and } for tok3
                     const Token *tok3 = tok2->tokAt(20);
@@ -1077,7 +1077,7 @@ void CheckStl::missingComparison()
                 break;
             }
 
-            const Token *incrementToken = 0;
+            const Token *incrementToken = nullptr;
 
             // Parse loop..
             for (const Token *tok3 = i->classStart; tok3 != i->classEnd; tok3 = tok3->next()) {
diff --git a/lib/checkunusedfunctions.cpp b/lib/checkunusedfunctions.cpp
index a846a63ca..b678d4fd1 100644
--- a/lib/checkunusedfunctions.cpp
+++ b/lib/checkunusedfunctions.cpp
@@ -51,7 +51,7 @@ void CheckUnusedFunctions::parseTokens(const Tokenizer &tokenizer, const char Fi
         if (tok->previous() && tok->previous()->str() == ">")
             continue;
 
-        const Token *funcname = 0;
+        const Token *funcname = nullptr;
 
         if (Token::Match(tok, "%type% %var% ("))
             funcname = tok->next();
@@ -188,7 +188,7 @@ void CheckUnusedFunctions::parseTokens(const Tokenizer &tokenizer, const char Fi
         }
 
 
-        const Token *funcname = 0;
+        const Token *funcname = nullptr;
 
         if (Token::Match(tok->next(), "%var% (")) {
             funcname = tok->next();
diff --git a/lib/checkunusedvar.cpp b/lib/checkunusedvar.cpp
index 89ab17db6..81a26bcbb 100644
--- a/lib/checkunusedvar.cpp
+++ b/lib/checkunusedvar.cpp
@@ -40,7 +40,7 @@ public:
     /** Store information about variable usage */
     class VariableUsage {
     public:
-        VariableUsage(const Variable *var = 0,
+        VariableUsage(const Variable *var = nullptr,
                       VariableType type = standard,
                       bool read = false,
                       bool write = false,
diff --git a/lib/cppcheck.cpp b/lib/cppcheck.cpp
index 389064426..5c8619574 100644
--- a/lib/cppcheck.cpp
+++ b/lib/cppcheck.cpp
@@ -449,7 +449,7 @@ void CppCheck::executeRules(const std::string &tokenlist, const Tokenizer &token
         if (rule.pattern.empty() || rule.id.empty() || rule.severity.empty() || rule.tokenlist != tokenlist)
             continue;
 
-        const char *error = 0;
+        const char *error = nullptr;
         int erroffset = 0;
         pcre *re = pcre_compile(rule.pattern.c_str(),0,&error,&erroffset,nullptr);
         if (!re) {
diff --git a/lib/preprocessor.h b/lib/preprocessor.h
index 84cdbe8c9..cd5e021ae 100644
--- a/lib/preprocessor.h
+++ b/lib/preprocessor.h
@@ -54,7 +54,7 @@ public:
     /** character that is inserted in expanded macros */
     static char macroChar;
 
-    Preprocessor(Settings *settings = 0, ErrorLogger *errorLogger = 0);
+    Preprocessor(Settings *settings = nullptr, ErrorLogger *errorLogger = nullptr);
 
     static bool missingIncludeFlag;
 
diff --git a/lib/symboldatabase.cpp b/lib/symboldatabase.cpp
index 650649ce0..5fa9481d7 100644
--- a/lib/symboldatabase.cpp
+++ b/lib/symboldatabase.cpp
@@ -310,8 +310,8 @@ SymbolDatabase::SymbolDatabase(const Tokenizer *tokenizer, const Settings *setti
 
             // check if in class or structure
             else if (scope->type == Scope::eClass || scope->type == Scope::eStruct) {
-                const Token *funcStart = 0;
-                const Token *argStart = 0;
+                const Token *funcStart = nullptr;
+                const Token *argStart = nullptr;
 
                 // What section are we in..
                 if (tok->str() == "private:")
@@ -558,8 +558,8 @@ SymbolDatabase::SymbolDatabase(const Tokenizer *tokenizer, const Settings *setti
                     scope->definedType->friendList.push_back(friendInfo);
                 }
             } else if (scope->type == Scope::eNamespace || scope->type == Scope::eGlobal) {
-                const Token *funcStart = 0;
-                const Token *argStart = 0;
+                const Token *funcStart = nullptr;
+                const Token *argStart = nullptr;
 
                 // function?
                 if (isFunction(tok, scope, &funcStart, &argStart)) {
@@ -2723,7 +2723,7 @@ bool SymbolDatabase::isCPP() const
 
 const Scope *SymbolDatabase::findScope(const Token *tok, const Scope *startScope) const
 {
-    const Scope *scope = 0;
+    const Scope *scope = nullptr;
     // absolute path
     if (tok->str() == "::") {
         tok = tok->next();
diff --git a/lib/token.cpp b/lib/token.cpp
index db48caf8b..4881ef9b5 100644
--- a/lib/token.cpp
+++ b/lib/token.cpp
@@ -846,7 +846,7 @@ Token* Token::nextArgument() const
 
 const Token * Token::findClosingBracket() const
 {
-    const Token *closing = 0;
+    const Token *closing = nullptr;
 
     if (_str == "<") {
         unsigned int depth = 0;
diff --git a/lib/token.h b/lib/token.h
index e4b9e1ceb..f3eee4df0 100644
--- a/lib/token.h
+++ b/lib/token.h
@@ -382,7 +382,7 @@ public:
      * @param title Title for the printout or use default parameter or 0
      * for no title.
      */
-    void printOut(const char *title = 0) const;
+    void printOut(const char *title = nullptr) const;
 
     /**
      * For debugging purposes, prints token and all tokens
@@ -591,7 +591,7 @@ public:
     }
 
     const ValueFlow::Value * getMaxValue(bool condition) const {
-        const ValueFlow::Value *ret = 0;
+        const ValueFlow::Value *ret = nullptr;
         std::list<ValueFlow::Value>::const_iterator it;
         for (it = values.begin(); it != values.end(); ++it) {
             if ((!ret || it->intvalue > ret->intvalue) &&
diff --git a/lib/tokenize.cpp b/lib/tokenize.cpp
index 5f24b9cc0..1b6c51ed5 100644
--- a/lib/tokenize.cpp
+++ b/lib/tokenize.cpp
@@ -603,19 +603,19 @@ void Tokenizer::simplifyTypedef()
 
         Token *typeName;
         std::list<std::string> pointers;
-        Token *typeStart = 0;
-        Token *typeEnd = 0;
-        Token *argStart = 0;
-        Token *argEnd = 0;
-        Token *arrayStart = 0;
-        Token *arrayEnd = 0;
-        Token *specStart = 0;
-        Token *specEnd = 0;
+        Token *typeStart = nullptr;
+        Token *typeEnd = nullptr;
+        Token *argStart = nullptr;
+        Token *argEnd = nullptr;
+        Token *arrayStart = nullptr;
+        Token *arrayEnd = nullptr;
+        Token *specStart = nullptr;
+        Token *specEnd = nullptr;
         Token *typeDef = tok;
-        Token *argFuncRetStart = 0;
-        Token *argFuncRetEnd = 0;
-        Token *funcStart = 0;
-        Token *funcEnd = 0;
+        Token *argFuncRetStart = nullptr;
+        Token *argFuncRetEnd = nullptr;
+        Token *funcStart = nullptr;
+        Token *funcEnd = nullptr;
         Token *tokOffset = tok->next();
         bool function = false;
         bool functionPtr = false;
@@ -626,8 +626,8 @@ void Tokenizer::simplifyTypedef()
         bool refToArray = false;
         bool ptrMember = false;
         bool typeOf = false;
-        Token *namespaceStart = 0;
-        Token *namespaceEnd = 0;
+        Token *namespaceStart = nullptr;
+        Token *namespaceEnd = nullptr;
 
         // check for invalid input
         if (!tok->next()) {
@@ -4440,7 +4440,7 @@ void Tokenizer::simplifyConditionOperator()
             else
                 tok->deleteNext(8);
 
-            Token *starttok = 0;
+            Token *starttok = nullptr;
 
             std::string str;
             if (isReturn)
@@ -7347,9 +7347,9 @@ void Tokenizer::simplifyEnum()
                 (!temp->isName() || !Token::Match(temp->next(), "[{:;]")))
                 continue;
             Token *start = tok;
-            Token *enumType = 0;
-            Token *typeTokenStart = 0;
-            Token *typeTokenEnd = 0;
+            Token *enumType = nullptr;
+            Token *typeTokenStart = nullptr;
+            Token *typeTokenEnd = nullptr;
 
             // check for C++0x enum class
             if (Token::Match(tok->next(), "class|struct"))
@@ -7965,7 +7965,7 @@ void Tokenizer::eraseDeadCode(Token *begin, const Token *end)
     std::vector<unsigned int> switchindents;
     bool checklabel = false;
     Token *tok = begin;
-    Token *tokcheck = 0;
+    Token *tokcheck = nullptr;
     while (tok->next() && tok->next() != end) {
         if (tok->next()->str() == "(") {
             ++roundbraces;
@@ -8639,11 +8639,11 @@ void Tokenizer::removeExceptionSpecifications()
 bool Tokenizer::validate() const
 {
     std::stack<const Token *> linktok;
-    const Token *lastTok = 0;
+    const Token *lastTok = nullptr;
     for (const Token *tok = tokens(); tok; tok = tok->next()) {
         lastTok = tok;
         if (Token::Match(tok, "[{([]") || (tok->str() == "<" && tok->link())) {
-            if (tok->link() == 0) {
+            if (tok->link() == nullptr) {
                 cppcheckError(tok);
                 return false;
             }
@@ -8652,7 +8652,7 @@ bool Tokenizer::validate() const
         }
 
         else if (Token::Match(tok, "[})]]") || (tok->str() == ">" && tok->link())) {
-            if (tok->link() == 0) {
+            if (tok->link() == nullptr) {
                 cppcheckError(tok);
                 return false;
             }
@@ -8675,7 +8675,7 @@ bool Tokenizer::validate() const
             linktok.pop();
         }
 
-        else if (tok->link() != 0) {
+        else if (tok->link() != nullptr) {
             cppcheckError(tok);
             return false;
         }
@@ -8867,7 +8867,7 @@ void Tokenizer::simplifyErrNoInWhile()
         if (tok->str() != "errno")
             continue;
 
-        Token *endpar = 0;
+        Token *endpar = nullptr;
         if (Token::Match(tok->previous(), "&& errno == EINTR ) { ;| }"))
             endpar = tok->tokAt(3);
         else if (Token::Match(tok->tokAt(-2), "&& ( errno == EINTR ) ) { ;| }"))
@@ -9018,7 +9018,7 @@ void Tokenizer::simplifyStructDecl()
                     }
                     if (!Token::simpleMatch(tok2, "} ;"))
                         continue;
-                    Token *vartok = 0;
+                    Token *vartok = nullptr;
                     tok2 = tok1->tokAt(2);
                     while (Token::Match(tok2, "%type% %var% ;")) {
                         if (!vartok) {
@@ -9295,7 +9295,7 @@ void Tokenizer::simplifyBitfields()
             goback = false;
             tok = tok->previous();
         }
-        Token *last = 0;
+        Token *last = nullptr;
 
         if (Token::Match(tok, ";|{|}|public:|protected:|private: const| %type% %var% :") &&
             !Token::Match(tok->next(), "case|public|protected|private|class|struct") &&
diff --git a/lib/tokenize.h b/lib/tokenize.h
index a89b74264..a3b1602b6 100644
--- a/lib/tokenize.h
+++ b/lib/tokenize.h
@@ -63,7 +63,7 @@ public:
      * \param unknown set to true if it's unknown if the scope is noreturn
      * \return true if scope ends with a function call that might be 'noreturn'
      */
-    bool IsScopeNoReturn(const Token *endScopeToken, bool *unknown = 0) const;
+    bool IsScopeNoReturn(const Token *endScopeToken, bool *unknown = nullptr) const;
 
     /**
      * Tokenize code
diff --git a/lib/tokenlist.cpp b/lib/tokenlist.cpp
index 4bbbea2d4..73f2d5bde 100644
--- a/lib/tokenlist.cpp
+++ b/lib/tokenlist.cpp
@@ -698,7 +698,7 @@ static Token * createAstAtToken(Token *tok)
 {
     if (Token::simpleMatch(tok,"for (")) {
         Token *tok2 = tok->tokAt(2);
-        Token *init1 = 0;
+        Token *init1 = nullptr;
         const Token * const endPar = tok->next()->link();
         while (tok2 && tok2 != endPar && tok2->str() != ";") {
             if (tok2->str() == "<" && tok2->link()) {
diff --git a/lib/valueflow.cpp b/lib/valueflow.cpp
index b884faf45..68330ec1f 100644
--- a/lib/valueflow.cpp
+++ b/lib/valueflow.cpp
@@ -608,7 +608,7 @@ static void valueFlowForLoop(TokenList *tokenlist, ErrorLogger *errorLogger, con
         if (vartok->varId() == 0U)
             continue;
         tok = vartok->tokAt(4);
-        const Token *num2tok = 0;
+        const Token *num2tok = nullptr;
         if (Token::Match(tok, "%varid% <|<=|!=", vartok->varId())) {
             tok = tok->next();
             num2tok = tok->astOperand2();
diff --git a/test/testsymboldatabase.cpp b/test/testsymboldatabase.cpp
index f26bbd94c..c75e1e731 100644
--- a/test/testsymboldatabase.cpp
+++ b/test/testsymboldatabase.cpp
@@ -836,7 +836,7 @@ private:
 
     void hasSubClassConstructor() {
         GET_SYMBOL_DB("class Foo { class Sub; }; class Foo::Sub { Sub() {} };");
-        ASSERT(db != 0);
+        ASSERT(db != nullptr);
 
         if (db) {
             bool seen_something = false;
@@ -930,11 +930,11 @@ private:
         ASSERT(db && db->scopeList.size() == 4);
         if (db) {
             const Scope* foo = db->findScopeByName("Foo");
-            ASSERT(foo != 0);
+            ASSERT(foo != nullptr);
             const Scope* bar1 = db->findScopeByName("Bar1");
-            ASSERT(bar1 != 0);
+            ASSERT(bar1 != nullptr);
             const Scope* bar2 = db->findScopeByName("Bar2");
-            ASSERT(bar2 != 0);
+            ASSERT(bar2 != nullptr);
 
             if (foo && bar1 && bar2) {
                 ASSERT(bar1->definedType->friendList.size() == 1 && bar1->definedType->friendList.front().name == "Foo" && bar1->definedType->friendList.front().type == foo->definedType);
@@ -1159,7 +1159,7 @@ private:
             }
         }
 
-        ASSERT(scope != 0);
+        ASSERT(scope != nullptr);
         if (!scope)
             return;
 
@@ -1193,7 +1193,7 @@ private:
             }
         }
 
-        ASSERT(scope != 0);
+        ASSERT(scope != nullptr);
         if (!scope)
             return;
 
@@ -1836,14 +1836,14 @@ private:
         ASSERT_EQUALS("", errout.str());
         if (db) {
             const Scope * bar = db->findScopeByName("bar");
-            ASSERT(bar != 0);
+            ASSERT(bar != nullptr);
             if (bar) {
                 unsigned int linenrs[] = { 2, 1 };
                 unsigned int index = 0;
                 for (const Token * tok = bar->classStart->next(); tok != bar->classEnd; tok = tok->next()) {
                     if (Token::Match(tok, "%var% (") && !tok->varId() && Token::simpleMatch(tok->linkAt(1), ") ;")) {
                         const Function * function = db->findFunction(tok);
-                        ASSERT(function != 0);
+                        ASSERT(function != nullptr);
                         if (function) {
                             std::stringstream expected;
                             expected << "Function call on line " << tok->linenr() << " calls function on line " << linenrs[index] << std::endl;