Fix #8159 FN unusedFunction: sole recursive call

lib/checkunusedfunctions.cpp

@@ -59,6 +59,11 @@ static std::string stripTemplateParameters(const std::string& funcName) {
 // FUNCTION USAGE - Check for unused functions etc
 //---------------------------------------------------------------------------
 
+static bool isRecursiveCall(const Token* ftok)
+{
+    return ftok->function() && ftok->function() == Scope::nestedInFunction(ftok->scope());
+}
+
 void CheckUnusedFunctions::parseTokens(const Tokenizer &tokenizer, const Settings &settings)
 {
     const char * const FileName = tokenizer.list.getFiles().front().c_str();
@@ -245,6 +250,8 @@ void CheckUnusedFunctions::parseTokens(const Tokenizer &tokenizer, const Setting
         }
 
         if (funcname) {
+            if (isRecursiveCall(funcname))
+                continue;
             const auto baseName = stripTemplateParameters(funcname->str());
             FunctionUsage &func = mFunctions[baseName];
             const std::string& called_from_file = tokenizer.list.getFiles()[funcname->fileIndex()];

lib/clangimport.cpp

@@ -330,7 +330,7 @@ namespace clangimport {
 
         void dumpAst(int num = 0, int indent = 0) const;
         void createTokens1(TokenList &tokenList) {
-            //dumpAst();
+            //dumpAst(); // TODO: reactivate or remove
             if (!tokenList.back()) {
                 setLocations(tokenList, 0, 1, 1);
                 // FIXME: treat as C++ if no filename (i.e. no lang) is specified for now
@@ -486,6 +486,7 @@ std::string clangimport::AstNode::getTemplateParameters() const
     return templateParameters + ">";
 }
 
+// cppcheck-suppress unusedFunction // only used in comment
 void clangimport::AstNode::dumpAst(int num, int indent) const
 {
     (void)num;

lib/mathlib.cpp

@@ -1274,44 +1274,6 @@ bool MathLib::isOctalDigit(char c)
     return (c >= '0' && c <= '7');
 }
 
-bool MathLib::isDigitSeparator(const std::string& iCode, std::string::size_type iPos)
-{
-    if (iPos == 0 || iPos >= iCode.size() || iCode[iPos] != '\'')
-        return false;
-    std::string::size_type i = iPos - 1;
-    while (std::isxdigit(iCode[i])) {
-        if (i == 0)
-            return true; // Only xdigits before '
-        --i;
-    }
-    if (i == iPos - 1) // No xdigit before '
-        return false;
-
-    switch (iCode[i]) {
-    case ' ':
-    case '.':
-    case ',':
-    case 'x':
-    case '(':
-    case '{':
-    case '+':
-    case '-':
-    case '*':
-    case '%':
-    case '/':
-    case '&':
-    case '|':
-    case '^':
-    case '~':
-    case '=':
-        return true;
-    case '\'':
-        return isDigitSeparator(iCode, i);
-    default:
-        return false;
-    }
-}
-
 MathLib::value operator+(const MathLib::value &v1, const MathLib::value &v2)
 {
     return MathLib::value::calc('+',v1,v2);

lib/mathlib.h

@@ -126,13 +126,6 @@ class CPPCHECKLIB MathLib {
     static bool isOctalDigit(char c);
 
     static unsigned int encodeMultiChar(const std::string& str);
-
-    /**
-     * \param[in] iCode Code being considered
-     * \param[in] iPos A posision within iCode
-     * \return Whether iCode[iPos] is a C++14 digit separator
-     */
-    static bool isDigitSeparator(const std::string& iCode, std::string::size_type iPos);
 };
 
 MathLib::value operator+(const MathLib::value &v1, const MathLib::value &v2);

lib/symboldatabase.cpp

@@ -1152,7 +1152,7 @@ void SymbolDatabase::createSymbolDatabaseSetFunctionPointers(bool firstPass)
             inTemplateArg = tok->link();
         if (inTemplateArg == tok)
             inTemplateArg = nullptr;
-        if (tok->isName() && !tok->function() && tok->varId() == 0 && ((tok->astParent() && tok->astParent()->isComparisonOp()) || Token::Match(tok, "%name% [{(,)>;]]")) && !isReservedName(tok)) {
+        if (tok->isName() && !tok->function() && tok->varId() == 0 && ((tok->astParent() && tok->astParent()->isComparisonOp()) || Token::Match(tok, "%name% [{(,)>;:]]")) && !isReservedName(tok)) {
             if (tok->strAt(1) == ">" && !tok->linkAt(1))
                 continue;
 

lib/token.cpp

@@ -1702,6 +1702,7 @@ std::string Token::astStringVerbose() const
     return ret;
 }
 
+// cppcheck-suppress unusedFunction // used in test
 std::string Token::astStringZ3() const
 {
     if (!astOperand1())

test/testmathlib.cpp

@@ -60,7 +60,6 @@ class TestMathLib : public TestFixture {
         TEST_CASE(tan);
         TEST_CASE(abs);
         TEST_CASE(toString);
-        TEST_CASE(CPP14DigitSeparators);
     }
 
     void isGreater() const {
@@ -1475,24 +1474,6 @@ class TestMathLib : public TestFixture {
         ASSERT_EQUALS("2.22507385851e-308", MathLib::toString(std::numeric_limits<double>::min()));
         ASSERT_EQUALS("1.79769313486e+308", MathLib::toString(std::numeric_limits<double>::max()));
     }
-
-    void CPP14DigitSeparators() const { // Ticket #7137, #7565
-        ASSERT(MathLib::isDigitSeparator("'", 0) == false);
-        ASSERT(MathLib::isDigitSeparator("123'0;", 3));
-        ASSERT(MathLib::isDigitSeparator("foo(1'2);", 5));
-        ASSERT(MathLib::isDigitSeparator("foo(1,1'2);", 7));
-        ASSERT(MathLib::isDigitSeparator("int a=1'234-1'2-'0';", 7));
-        ASSERT(MathLib::isDigitSeparator("int a=1'234-1'2-'0';", 13));
-        ASSERT(MathLib::isDigitSeparator("int a=1'234-1'2-'0';", 16) == false);
-        ASSERT(MathLib::isDigitSeparator("int b=1+9'8;", 9));
-        ASSERT(MathLib::isDigitSeparator("if (1'2) { char c = 'c'; }", 5));
-        ASSERT(MathLib::isDigitSeparator("if (120%1'2) { char c = 'c'; }", 9));
-        ASSERT(MathLib::isDigitSeparator("if (120&1'2) { char c = 'c'; }", 9));
-        ASSERT(MathLib::isDigitSeparator("if (120|1'2) { char c = 'c'; }", 9));
-        ASSERT(MathLib::isDigitSeparator("if (120%1'2) { char c = 'c'; }", 24) == false);
-        ASSERT(MathLib::isDigitSeparator("if (120%1'2) { char c = 'c'; }", 26) == false);
-        ASSERT(MathLib::isDigitSeparator("0b0000001'0010'01110", 14));
-    }
 };
 
 REGISTER_TEST(TestMathLib)

test/testunusedfunctions.cpp

@@ -67,6 +67,7 @@ class TestUnusedFunctions : public TestFixture {
         TEST_CASE(member_function_ternary);
         TEST_CASE(boost);
         TEST_CASE(enumValues);
+        TEST_CASE(recursive);
 
         TEST_CASE(multipleFiles);   // same function name in multiple files
 
@@ -116,23 +117,23 @@ class TestUnusedFunctions : public TestFixture {
               "    if (f1())\n"
               "    { }\n"
               "}");
-        ASSERT_EQUALS("", errout_str());
+        ASSERT_EQUALS("[test.cpp:1]: (style) The function 'f1' is never used.\n", errout_str());
     }
 
     void return1() {
         check("int f1()\n"
               "{\n"
               "    return f1();\n"
               "}");
-        ASSERT_EQUALS("", errout_str());
+        ASSERT_EQUALS("[test.cpp:1]: (style) The function 'f1' is never used.\n", errout_str());
     }
 
     void return2() {
         check("char * foo()\n"
               "{\n"
-              "    return *foo();\n"
+              "    return foo();\n"
               "}");
-        ASSERT_EQUALS("", errout_str());
+        ASSERT_EQUALS("[test.cpp:1]: (style) The function 'foo' is never used.\n", errout_str());
     }
 
     void return3() {
@@ -158,7 +159,7 @@ class TestUnusedFunctions : public TestFixture {
               "{\n"
               "    void (*f)() = cond ? f1 : NULL;\n"
               "}");
-        ASSERT_EQUALS("", errout_str());
+        ASSERT_EQUALS("[test.cpp:1]: (style) The function 'f1' is never used.\n", errout_str());
     }
 
     void callback2() { // #8677
@@ -180,7 +181,7 @@ class TestUnusedFunctions : public TestFixture {
               "    if (cond) ;\n"
               "    else f1();\n"
               "}");
-        ASSERT_EQUALS("", errout_str());
+        ASSERT_EQUALS("[test.cpp:1]: (style) The function 'f1' is never used.\n", errout_str());
     }
 
     void functionpointer() {
@@ -255,7 +256,7 @@ class TestUnusedFunctions : public TestFixture {
               "}\n"
               "\n"
               "void h() { g<int>(); h(); }");
-        ASSERT_EQUALS("", errout_str());
+        ASSERT_EQUALS("[test.cpp:8]: (style) The function 'h' is never used.\n", errout_str());
     }
 
     void template3() { // #4701
@@ -286,7 +287,7 @@ class TestUnusedFunctions : public TestFixture {
               "        test();\n"
               "    }\n"
               "};");
-        ASSERT_EQUALS("", errout_str());
+        ASSERT_EQUALS("[test.cpp:11]: (style) The function 'test' is never used.\n", errout_str());
     }
 
     void template5() { // #9220
@@ -322,7 +323,7 @@ class TestUnusedFunctions : public TestFixture {
               "};\n");
         ASSERT_EQUALS("[test.cpp:3]: (style) The function 'tf' is never used.\n", errout_str());
 
-        check("struct S {\n"
+        check("struct C {\n"
               "    template<typename T>\n"
               "    void tf(const T&) { }\n"
               "};\n"
@@ -332,7 +333,7 @@ class TestUnusedFunctions : public TestFixture {
               "}\n");
         ASSERT_EQUALS("", errout_str());
 
-        check("struct S {\n"
+        check("struct C {\n"
               "    template<typename T>\n"
               "    void tf(const T&) { }\n"
               "};\n"
@@ -523,10 +524,11 @@ class TestUnusedFunctions : public TestFixture {
     }
 
     void boost() {
-        check("static void _xy(const char *b, const char *e)\n"
-              "{}\n"
-              "parse(line, blanks_p >> ident[&_xy] >> blanks_p >> eol_p).full");
-        ASSERT_EQUALS("", errout_str());
+        check("static void _xy(const char *b, const char *e) {}\n"
+              "void f() {\n"
+              "    parse(line, blanks_p >> ident[&_xy] >> blanks_p >> eol_p).full;\n"
+              "}\n");
+        ASSERT_EQUALS("[test.cpp:2]: (style) The function 'f' is never used.\n", errout_str());
     }
 
     void enumValues() { // #11486
@@ -541,6 +543,14 @@ class TestUnusedFunctions : public TestFixture {
                       errout_str());
     }
 
+    void recursive() {
+        check("void f() {\n" // #8159
+              "    f();\n"
+              "}\n");
+        ASSERT_EQUALS("[test.cpp:1]: (style) The function 'f' is never used.\n",
+                      errout_str());
+    }
+
     void multipleFiles() {
         CheckUnusedFunctions c;
 
@@ -576,7 +586,7 @@ class TestUnusedFunctions : public TestFixture {
         ASSERT_EQUALS("[test.cpp:2]: (style) The function 'f' is never used.\n", errout_str());
 
         check("void f(void) {}\n"
-              "void (*list[])(void) = {f}");
+              "void (*list[])(void) = {f};");
         ASSERT_EQUALS("", errout_str());
     }