diff --git a/lib/token.cpp b/lib/token.cpp
index b488afb4b..ce30afae8 100644
--- a/lib/token.cpp
+++ b/lib/token.cpp
@@ -42,7 +42,7 @@ Token::Token(TokensFrontBack *tokensFrontBack) :
     _link(nullptr),
     _scope(nullptr),
     _function(nullptr), // Initialize whole union
-    _varId(0),
+    mVarId(0),
     _fileIndex(0),
     _linenr(0),
     _col(0),
@@ -88,7 +88,7 @@ void Token::update_property_info()
         if (_str == "true" || _str == "false")
             tokType(eBoolean);
         else if (std::isalpha((unsigned char)_str[0]) || _str[0] == '_' || _str[0] == '$') { // Name
-            if (_varId)
+            if (mVarId)
                 tokType(eVariable);
             else if (_tokType != eVariable && _tokType != eFunction && _tokType != eType && _tokType != eKeyword)
                 tokType(eName);
@@ -249,7 +249,7 @@ void Token::swapWithNext()
         std::swap(_str, mNext->_str);
         std::swap(_tokType, mNext->_tokType);
         std::swap(mFlags, mNext->mFlags);
-        std::swap(_varId, mNext->_varId);
+        std::swap(mVarId, mNext->mVarId);
         std::swap(_fileIndex, mNext->_fileIndex);
         std::swap(_linenr, mNext->_linenr);
         if (mNext->_link)
@@ -271,7 +271,7 @@ void Token::takeData(Token *fromToken)
     _str = fromToken->_str;
     tokType(fromToken->_tokType);
     mFlags = fromToken->mFlags;
-    _varId = fromToken->_varId;
+    mVarId = fromToken->mVarId;
     _fileIndex = fromToken->_fileIndex;
     _linenr = fromToken->_linenr;
     _link = fromToken->_link;
@@ -1024,8 +1024,8 @@ void Token::stringify(std::ostream& os, bool varid, bool attributes, bool macro)
                 os << _str[i];
         }
     }
-    if (varid && _varId != 0)
-        os << '@' << _varId;
+    if (varid && mVarId != 0)
+        os << '@' << mVarId;
 }
 
 std::string Token::stringifyList(bool varid, bool attributes, bool linenumbers, bool linebreaks, bool files, const std::vector<std::string>* fileNames, const Token* end) const
@@ -1621,7 +1621,7 @@ bool Token::addValue(const ValueFlow::Value &value)
             if (it->isInconclusive() && !value.isInconclusive()) {
                 *it = value;
                 if (it->varId == 0)
-                    it->varId = _varId;
+                    it->varId = mVarId;
                 break;
             }
 
@@ -1633,13 +1633,13 @@ bool Token::addValue(const ValueFlow::Value &value)
         if (it == _values->end()) {
             ValueFlow::Value v(value);
             if (v.varId == 0)
-                v.varId = _varId;
+                v.varId = mVarId;
             _values->push_back(v);
         }
     } else {
         ValueFlow::Value v(value);
         if (v.varId == 0)
-            v.varId = _varId;
+            v.varId = mVarId;
         _values = new std::list<ValueFlow::Value>(1, v);
     }
 
diff --git a/lib/token.h b/lib/token.h
index 39c1d567a..3956c5d0c 100644
--- a/lib/token.h
+++ b/lib/token.h
@@ -84,7 +84,7 @@ public:
     template<typename T>
     void str(T&& s) {
         _str = s;
-        _varId = 0;
+        mVarId = 0;
 
         update_property_info();
     }
@@ -559,10 +559,10 @@ public:
 
 
     unsigned int varId() const {
-        return _varId;
+        return mVarId;
     }
     void varId(unsigned int id) {
-        _varId = id;
+        mVarId = id;
         if (id != 0) {
             tokType(eVariable);
             isStandardType(false);
@@ -696,7 +696,7 @@ public:
      */
     void variable(const Variable *v) {
         _variable = v;
-        if (v || _varId)
+        if (v || mVarId)
             tokType(eVariable);
         else if (_tokType == eVariable)
             tokType(eName);
@@ -918,7 +918,7 @@ private:
         const Enumerator *_enumerator;
     };
 
-    unsigned int _varId;
+    unsigned int mVarId;
     unsigned int _fileIndex;
     unsigned int _linenr;
     unsigned int _col;
diff --git a/lib/tokenize.cpp b/lib/tokenize.cpp
index c93281a46..a084fe12e 100644
--- a/lib/tokenize.cpp
+++ b/lib/tokenize.cpp
@@ -143,7 +143,7 @@ Tokenizer::Tokenizer() :
     mSettings(nullptr),
     mErrorLogger(nullptr),
     mSymbolDatabase(nullptr),
-    _varId(0),
+    mVarId(0),
     _unnamedCount(0),
     _codeWithTemplates(false), //is there any templates?
     _timerResults(nullptr)
@@ -158,7 +158,7 @@ Tokenizer::Tokenizer(const Settings *settings, ErrorLogger *errorLogger) :
     mSettings(settings),
     mErrorLogger(errorLogger),
     mSymbolDatabase(nullptr),
-    _varId(0),
+    mVarId(0),
     _unnamedCount(0),
     _codeWithTemplates(false), //is there any templates?
     _timerResults(nullptr)
@@ -2525,7 +2525,7 @@ static void setVarIdClassFunction(const std::string &classname,
                                   const Token * const endToken,
                                   const std::map<std::string, unsigned int> &varlist,
                                   std::map<unsigned int, std::map<std::string, unsigned int> >& structMembers,
-                                  unsigned int *_varId)
+                                  unsigned int *varId_)
 {
     for (Token *tok2 = startToken; tok2 && tok2 != endToken; tok2 = tok2->next()) {
         if (tok2->varId() != 0 || !tok2->isName())
@@ -2540,7 +2540,7 @@ static void setVarIdClassFunction(const std::string &classname,
         const std::map<std::string,unsigned int>::const_iterator it = varlist.find(tok2->str());
         if (it != varlist.end()) {
             tok2->varId(it->second);
-            setVarIdStructMembers(&tok2, structMembers, _varId);
+            setVarIdStructMembers(&tok2, structMembers, varId_);
         }
     }
 }
@@ -2842,7 +2842,7 @@ void Tokenizer::setVarIdPass1()
         }
     }
 
-    _varId = *variableMap.getVarId();
+    mVarId = *variableMap.getVarId();
 }
 
 namespace {
@@ -3057,7 +3057,7 @@ void Tokenizer::setVarIdPass2()
             if (tok2->link()) {
                 if (tok2->str() == "{") {
                     if (tok2->strAt(-1) == ")" || tok2->strAt(-2) == ")")
-                        setVarIdClassFunction(scopeName2 + classname, tok2, tok2->link(), thisClassVars, structMembers, &_varId);
+                        setVarIdClassFunction(scopeName2 + classname, tok2, tok2->link(), thisClassVars, structMembers, &mVarId);
                     tok2 = tok2->link();
                 } else if (tok2->str() == "(" && tok2->link()->strAt(1) != "(")
                     tok2 = tok2->link();
@@ -3097,7 +3097,7 @@ void Tokenizer::setVarIdPass2()
             // If this is a function implementation.. add it to funclist
             Token * start = const_cast<Token *>(isFunctionHead(tok2, "{"));
             if (start) {
-                setVarIdClassFunction(classname, start, start->link(), thisClassVars, structMembers, &_varId);
+                setVarIdClassFunction(classname, start, start->link(), thisClassVars, structMembers, &mVarId);
             }
 
             if (Token::Match(tok2, ") %name% ("))
@@ -3131,7 +3131,7 @@ void Tokenizer::setVarIdPass2()
                     tok3 = tok3->linkAt(1);
             }
             if (Token::Match(tok3, ")|} {")) {
-                setVarIdClassFunction(classname, tok2, tok3->next()->link(), thisClassVars, structMembers, &_varId);
+                setVarIdClassFunction(classname, tok2, tok3->next()->link(), thisClassVars, structMembers, &mVarId);
             }
         }
     }
@@ -8658,7 +8658,7 @@ void Tokenizer::simplifyFuncInWhile()
         Token *var = tok->tokAt(4);
         Token *end = tok->next()->link()->next()->link();
 
-        const unsigned int varid = ++_varId; // Create new variable
+        const unsigned int varid = ++mVarId; // Create new variable
         const std::string varname("cppcheck:r" + MathLib::toString(++count));
         tok->str("int");
         tok->next()->insertToken(varname);
@@ -9937,7 +9937,7 @@ void Tokenizer::printUnknownTypes() const
 
     std::multimap<std::string, const Token *> unknowns;
 
-    for (unsigned int i = 1; i <= _varId; ++i) {
+    for (unsigned int i = 1; i <= mVarId; ++i) {
         const Variable *var = mSymbolDatabase->getVariableFromVarId(i);
         if (!var)
             continue;
diff --git a/lib/tokenize.h b/lib/tokenize.h
index d21fb6542..dd505140d 100644
--- a/lib/tokenize.h
+++ b/lib/tokenize.h
@@ -795,7 +795,7 @@ public:
      * @return number of variables
      */
     unsigned int varIdCount() const {
-        return _varId;
+        return mVarId;
     }
 
     /**
@@ -859,7 +859,7 @@ private:
     * @return new variable id
     */
     unsigned int newVarId() {
-        return ++_varId;
+        return ++mVarId;
     }
 
     /** Set pod types */
@@ -882,7 +882,7 @@ private:
     std::map<std::string, unsigned int> _typeSize;
 
     /** variable count */
-    unsigned int _varId;
+    unsigned int mVarId;
 
     /** unnamed count "Unnamed0", "Unnamed1", "Unnamed2", ... */
     unsigned int _unnamedCount;