From 1245f1d6211188833581e0600bf4c2029094ce45 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Marjam=C3=A4ki?= <daniel.marjamaki@gmail.com>
Date: Mon, 7 Nov 2016 21:49:58 +0100
Subject: [PATCH] Unused Functions: Fix checking when --cppcheck-build-dir is
 used.

---
 lib/checkunusedfunctions.cpp | 17 ++++++++++++-----
 lib/checkunusedfunctions.h   |  4 ++--
 lib/cppcheck.cpp             | 14 ++++++++++----
 3 files changed, 24 insertions(+), 11 deletions(-)

diff --git a/lib/checkunusedfunctions.cpp b/lib/checkunusedfunctions.cpp
index 3baafb900..fa18415ef 100644
--- a/lib/checkunusedfunctions.cpp
+++ b/lib/checkunusedfunctions.cpp
@@ -39,13 +39,14 @@ static const struct CWE CWE561(561U);   // Dead Code
 // FUNCTION USAGE - Check for unused functions etc
 //---------------------------------------------------------------------------
 
-void CheckUnusedFunctions::parseTokens(const Tokenizer &tokenizer, const char FileName[], const Settings *settings)
+void CheckUnusedFunctions::parseTokens(const Tokenizer &tokenizer, const char FileName[], const Settings *settings, bool clear)
 {
     const bool doMarkup = settings->library.markupFile(FileName);
     const SymbolDatabase* symbolDatabase = tokenizer.getSymbolDatabase();
 
     // Function declarations..
-    _functionDecl.clear();
+    if (clear)
+        _functionDecl.clear();
     for (std::size_t i = 0; i < symbolDatabase->functionScopes.size(); i++) {
         const Scope* scope = symbolDatabase->functionScopes[i];
         const Function* func = scope->function;
@@ -79,7 +80,8 @@ void CheckUnusedFunctions::parseTokens(const Tokenizer &tokenizer, const char Fi
     }
 
     // Function usage..
-    _functionCalls.clear();
+    if (clear)
+        _functionCalls.clear();
     for (const Token *tok = tokenizer.tokens(); tok; tok = tok->next()) {
 
         // parsing of library code to find called functions
@@ -293,12 +295,12 @@ CheckUnusedFunctions::FunctionDecl::FunctionDecl(const Function *f)
 std::string CheckUnusedFunctions::analyzerInfo() const
 {
     std::ostringstream ret;
-    for (std::list<FunctionDecl>::const_iterator it = instance._functionDecl.begin(); it != instance._functionDecl.end(); ++it) {
+    for (std::list<FunctionDecl>::const_iterator it = _functionDecl.begin(); it != _functionDecl.end(); ++it) {
         ret << "    <functiondecl"
             << " functionName=\"" << ErrorLogger::toxml(it->functionName) << '\"'
             << " lineNumber=\"" << it->lineNumber << "\"/>\n";
     }
-    for (std::set<std::string>::const_iterator it = instance._functionCalls.begin(); it != instance._functionCalls.end(); ++it) {
+    for (std::set<std::string>::const_iterator it = _functionCalls.begin(); it != _functionCalls.end(); ++it) {
         ret << "    <functioncall functionName=\"" << ErrorLogger::toxml(*it) << "\"/>\n";
     }
     return ret.str();
@@ -351,6 +353,11 @@ void CheckUnusedFunctions::analyseWholeProgram(ErrorLogger * const errorLogger,
 
     for (std::map<std::string, Location>::const_iterator decl = decls.begin(); decl != decls.end(); ++decl) {
         const std::string &functionName = decl->first;
+
+        if (functionName == "main" || functionName == "WinMain" || functionName == "_tmain" ||
+            functionName == "if" || functionName.compare(0, 8, "operator") == 0)
+            continue;
+
         if (calls.find(functionName) == calls.end()) {
             const Location &loc = decl->second;
             unusedFunctionError(errorLogger, loc.fileName, loc.lineNumber, functionName);
diff --git a/lib/checkunusedfunctions.h b/lib/checkunusedfunctions.h
index d59cc6efe..55c567878 100644
--- a/lib/checkunusedfunctions.h
+++ b/lib/checkunusedfunctions.h
@@ -47,7 +47,7 @@ public:
     // Parse current tokens and determine..
     // * Check what functions are used
     // * What functions are declared
-    void parseTokens(const Tokenizer &tokenizer, const char FileName[], const Settings *settings);
+    void parseTokens(const Tokenizer &tokenizer, const char FileName[], const Settings *settings, bool clear=true);
 
     void check(ErrorLogger * const errorLogger, const Settings& settings);
 
@@ -62,7 +62,7 @@ public:
     std::string analyzerInfo() const;
 
     /** @brief Combine and analyze all analyzerInfos for all TUs */
-    void analyseWholeProgram(ErrorLogger * const errorLogger, const std::string &buildDir, const std::map<std::string, std::size_t> &files);
+    static void analyseWholeProgram(ErrorLogger * const errorLogger, const std::string &buildDir, const std::map<std::string, std::size_t> &files);
 
 private:
 
diff --git a/lib/cppcheck.cpp b/lib/cppcheck.cpp
index 75a9cf9a8..fc7735a43 100644
--- a/lib/cppcheck.cpp
+++ b/lib/cppcheck.cpp
@@ -122,6 +122,8 @@ unsigned int CppCheck::processFile(const std::string& filename, const std::strin
         }
     }
 
+    CheckUnusedFunctions checkUnusedFunctions;
+
     bool internalErrorFound(false);
     try {
         Preprocessor preprocessor(_settings, this);
@@ -316,6 +318,10 @@ unsigned int CppCheck::processFile(const std::string& filename, const std::strin
                 // Check normal tokens
                 checkNormalTokens(_tokenizer);
 
+                // Analyze info..
+                if (!_settings.buildDir.empty())
+                    checkUnusedFunctions.parseTokens(_tokenizer, filename.c_str(), &_settings, false);
+
                 // simplify more if required, skip rest of iteration if failed
                 if (_simplify) {
                     // if further simplification fails then skip rest of iteration
@@ -368,7 +374,7 @@ unsigned int CppCheck::processFile(const std::string& filename, const std::strin
         exitcode=1; // e.g. reflect a syntax error
     }
 
-    analyzerInformation.setFileInfo("CheckUnusedFunctions", CheckUnusedFunctions::instance.analyzerInfo());
+    analyzerInformation.setFileInfo("CheckUnusedFunctions", checkUnusedFunctions.analyzerInfo());
     analyzerInformation.close();
 
     // In jointSuppressionReport mode, unmatched suppressions are
@@ -733,11 +739,11 @@ void CppCheck::analyseWholeProgram(const std::string &buildDir, const std::map<s
 {
     if (buildDir.empty())
         return;
-//    if (_settings.isEnabled("unusedFunction"))
-//        CheckUnusedFunctions::instance.analyseWholeProgram(this, buildDir, files);
+    if (_settings.isEnabled("unusedFunction"))
+        CheckUnusedFunctions::analyseWholeProgram(this, buildDir, files);
 }
 
 bool CppCheck::isUnusedFunctionCheckEnabled() const
 {
-    return ((_settings.jobs == 1 || !_settings.buildDir.empty()) && _settings.isEnabled("unusedFunction"));
+    return (_settings.jobs == 1 && _settings.isEnabled("unusedFunction"));
 }