only create or set Token::mMacroName if necessary (danmar#7358)

like we do with `Token::mOriginalName`

Author: firewave

lib/token.cpp

@@ -1048,7 +1048,8 @@ Token* Token::insertToken(const std::string& tokenStr, const std::string& origin
     newToken->str(tokenStr);
     if (!originalNameStr.empty())
         newToken->originalName(originalNameStr);
-    newToken->setMacroName(macroNameStr);
+    if (!macroNameStr.empty())
+        newToken->setMacroName(macroNameStr);
 
     if (newToken != this) {
         newToken->mImpl->mLineNumber = mImpl->mLineNumber;
@@ -2599,6 +2600,7 @@ const ValueFlow::Value* Token::getContainerSizeValue(const MathLib::bigint val)
 
 TokenImpl::~TokenImpl()
 {
+    delete mMacroName;
     delete mOriginalName;
     delete mValueType;
     delete mValues;

lib/token.h

@@ -101,7 +101,7 @@ struct TokenImpl {
     std::string* mOriginalName{};
 
     // If this token came from a macro replacement list, this is the name of that macro
-    std::string mMacroName;
+    std::string* mMacroName{};
 
     // ValueType
     ValueType* mValueType{};
@@ -480,7 +480,7 @@ class CPPCHECKLIB Token {
         setFlag(fIsStandardType, b);
     }
     bool isExpandedMacro() const {
-        return !mImpl->mMacroName.empty();
+        return !!mImpl->mMacroName;
     }
     bool isCast() const {
         return getFlag(fIsCast);
@@ -805,10 +805,13 @@ class CPPCHECKLIB Token {
     }
 
     const std::string& getMacroName() const {
-        return mImpl->mMacroName;
+        return mImpl->mMacroName ? *mImpl->mMacroName : mEmptyString;
     }
     void setMacroName(std::string name) {
-        mImpl->mMacroName = std::move(name);
+        if (!mImpl->mMacroName)
+            mImpl->mMacroName = new std::string(std::move(name));
+        else
+            *mImpl->mMacroName = std::move(name);
     }
 
     template<size_t count>

lib/tokenize.cpp

@@ -781,7 +781,8 @@ namespace {
                 if (pointerType) {
                     tok->insertToken("const");
                     tok->next()->column(tok->column());
-                    tok->next()->setMacroName(tok->previous()->getMacroName());
+                    if (!tok->previous()->getMacroName().empty())
+                        tok->next()->setMacroName(tok->previous()->getMacroName());
                     tok->deletePrevious();
                 }
             }
@@ -7319,7 +7320,8 @@ void Tokenizer::simplifyVarDecl(Token * tokBegin, const Token * const tokEnd, co
                 endDecl = endDecl->next();
                 endDecl->next()->isSplittedVarDeclEq(true);
                 endDecl->insertToken(varName->str());
-                endDecl->next()->setMacroName(varName->getMacroName());
+                if (!varName->getMacroName().empty())
+                    endDecl->next()->setMacroName(varName->getMacroName());
                 continue;
             }
             //non-VLA case

lib/tokenlist.cpp

@@ -255,7 +255,8 @@ void TokenList::addtoken(const Token *tok)
         mTokensFrontBack.back->str(tok->str());
         if (!tok->originalName().empty())
             mTokensFrontBack.back->originalName(tok->originalName());
-        mTokensFrontBack.back->setMacroName(tok->getMacroName());
+        if (!tok->getMacroName().empty())
+            mTokensFrontBack.back->setMacroName(tok->getMacroName());
     }
 
     mTokensFrontBack.back->flags(tok->flags());
@@ -332,7 +333,8 @@ void TokenList::insertTokens(Token *dest, const Token *src, nonneg int n)
         dest->varId(src->varId());
         dest->tokType(src->tokType());
         dest->flags(src->flags());
-        dest->setMacroName(src->getMacroName());
+        if (!src->getMacroName().empty())
+            dest->setMacroName(src->getMacroName());
         src  = src->next();
         --n;
     }
@@ -415,7 +417,8 @@ void TokenList::createTokens(simplecpp::TokenList&& tokenList)
         mTokensFrontBack.back->fileIndex(tok->location.fileIndex);
         mTokensFrontBack.back->linenr(tok->location.line);
         mTokensFrontBack.back->column(tok->location.col);
-        mTokensFrontBack.back->setMacroName(tok->macro);
+        if (!tok->macro.empty())
+            mTokensFrontBack.back->setMacroName(tok->macro);
 
         tok = tok->next;
         if (tok)