From 90bc59e0fa7b3fbdfea68ad9bfc9188fe57abdd5 Mon Sep 17 00:00:00 2001
From: Robert Reif <reif@earthlink.net>
Date: Mon, 28 Jul 2014 09:16:35 +0200
Subject: [PATCH] Fixed #6009 (Detect type mismatch in printf-like function
 when type is returned)

---
 lib/checkio.cpp | 12 ++++++------
 test/testio.cpp |  9 +++++++++
 2 files changed, 15 insertions(+), 6 deletions(-)

diff --git a/lib/checkio.cpp b/lib/checkio.cpp
index add5c35da..e28bf18d2 100644
--- a/lib/checkio.cpp
+++ b/lib/checkio.cpp
@@ -1013,7 +1013,7 @@ void CheckIO::checkWrongPrintfScanfArguments()
                                 while (!done) {
                                     switch (*i) {
                                     case 's':
-                                        if (argInfo.variableInfo && argListTok->type() != Token::eString &&
+                                        if (argListTok->type() != Token::eString &&
                                             argInfo.isKnownType() && !argInfo.isArrayOrPointer()) {
                                             if (!Token::Match(argInfo.typeToken, "char|wchar_t")) {
                                                 if (!(!argInfo.isArrayOrPointer() && argInfo.element))
@@ -1023,7 +1023,7 @@ void CheckIO::checkWrongPrintfScanfArguments()
                                         done = true;
                                         break;
                                     case 'n':
-                                        if ((argInfo.variableInfo && argInfo.isKnownType() && (!argInfo.isArrayOrPointer() || argInfo.typeToken->strAt(-1) == "const")) || argListTok->type() == Token::eString)
+                                        if ((argInfo.isKnownType() && (!argInfo.isArrayOrPointer() || argInfo.typeToken->strAt(-1) == "const")) || argListTok->type() == Token::eString)
                                             invalidPrintfArgTypeError_n(tok, numFormat, &argInfo);
                                         done = true;
                                         break;
@@ -1362,7 +1362,7 @@ CheckIO::ArgumentInfo::ArgumentInfo(const Token * tok, const Settings *settings)
                     Token::Match(tok->linkAt(1)->linkAt(1), ") ,|)"))) {
             if (Token::Match(tok, "static_cast|reinterpret_cast|const_cast")) {
                 typeToken = tok->tokAt(2);
-                if (typeToken->str() == "const")
+                while (typeToken->str() == "const" || typeToken->str() == "extern")
                     typeToken = typeToken->next();
                 return;
             }
@@ -1384,7 +1384,7 @@ CheckIO::ArgumentInfo::ArgumentInfo(const Token * tok, const Settings *settings)
                             const Function * function = varTok->link()->previous()->function();
                             if (function && function->retDef) {
                                 typeToken = function->retDef;
-                                if (typeToken->str() == "const")
+                                while (typeToken->str() == "const" || typeToken->str() == "extern")
                                     typeToken = typeToken->next();
                                 functionInfo = function;
                                 element = true;
@@ -1396,7 +1396,7 @@ CheckIO::ArgumentInfo::ArgumentInfo(const Token * tok, const Settings *settings)
                         const Function * function = tok1->linkAt(-1)->previous()->function();
                         if (function && function->retDef) {
                             typeToken = function->retDef;
-                            if (typeToken->str() == "const")
+                            while (typeToken->str() == "const" || typeToken->str() == "extern")
                                 typeToken = typeToken->next();
                             functionInfo = function;
                             element = false;
@@ -1620,7 +1620,7 @@ bool CheckIO::ArgumentInfo::isKnownType() const
     if (variableInfo)
         return (typeToken->isStandardType() || typeToken->next()->isStandardType() || isComplexType());
     else if (functionInfo)
-        return (typeToken->isStandardType() || functionInfo->retType);
+        return (typeToken->isStandardType() || functionInfo->retType || Token::Match(typeToken, "std :: string|wstring"));
 
     return typeToken->isStandardType() || Token::Match(typeToken, "std :: string|wstring");
 }
diff --git a/test/testio.cpp b/test/testio.cpp
index 53b6cc935..9348bff41 100644
--- a/test/testio.cpp
+++ b/test/testio.cpp
@@ -3079,6 +3079,15 @@ private:
               "}\n");
         ASSERT_EQUALS("", errout.str());
 
+        // #6009
+        check("extern std::string StringByReturnValue();\n"
+              "extern int         IntByReturnValue();\n"
+              "void MyFunction() {\n"
+              "    printf( \"%s - %s\", StringByReturnValue(), IntByReturnValue() );\n"
+              "}\n");
+        ASSERT_EQUALS("[test.cpp:4]: (warning) %s in format string (no. 1) requires 'char *' but the argument type is 'std::string'.\n"
+                      "[test.cpp:4]: (warning) %s in format string (no. 2) requires 'char *' but the argument type is 'int'.\n", errout.str());
+
     }
 
     void testPosixPrintfScanfParameterPosition() { // #4900  - No support for parameters in format strings