Fixed #13527 - FN: stringCompare (wcsicmp) (danmar#7186)

Author: orbitcowboy

lib/checkstring.cpp

@@ -102,7 +102,7 @@ void CheckString::checkAlwaysTrueOrFalseStringCompare()
     logChecker("CheckString::checkAlwaysTrueOrFalseStringCompare"); // warning
 
     for (const Token* tok = mTokenizer->tokens(); tok; tok = tok->next()) {
-        if (tok->isName() && tok->strAt(1) == "(" && Token::Match(tok, "memcmp|strncmp|strcmp|stricmp|strverscmp|bcmp|strcmpi|strcasecmp|strncasecmp|strncasecmp_l|strcasecmp_l|wcsncasecmp|wcscasecmp|wmemcmp|wcscmp|wcscasecmp_l|wcsncasecmp_l|wcsncmp|_mbscmp|_mbscmp_l|_memicmp|_memicmp_l|_stricmp|_wcsicmp|_mbsicmp|_stricmp_l|_wcsicmp_l|_mbsicmp_l")) {
+        if (tok->isName() && tok->strAt(1) == "(" && Token::Match(tok, "memcmp|strncmp|strcmp|stricmp|strverscmp|bcmp|strcmpi|strcasecmp|strncasecmp|strncasecmp_l|strcasecmp_l|wcsncasecmp|wcscasecmp|wmemcmp|wcscmp|wcscasecmp_l|wcsncasecmp_l|wcsncmp|_mbscmp|_mbscmp_l|_memicmp|_memicmp_l|_stricmp|_wcsicmp|wcsicmp|_mbsicmp|_stricmp_l|_wcsicmp_l|_mbsicmp_l")) {
             if (Token::Match(tok->tokAt(2), "%str% , %str% ,|)")) {
                 const std::string &str1 = tok->strAt(2);
                 const std::string &str2 = tok->strAt(4);

test/teststring.cpp

@@ -197,6 +197,12 @@ class TestString : public TestFixture {
               "}");
         ASSERT_EQUALS("", errout_str());
 
+        check("int f(void) {\n" // #13527
+              "    const wchar_t* str1 = L\"Hello\";\n"
+              "    return wcsicmp(str1, str1);\n" // <<
+              "}");
+        ASSERT_EQUALS("[test.cpp:3]: (warning) Comparison of identical string variables.\n", errout_str());
+
         check("int main()\n"
               "{\n"
               "  if (strcmp(\"00FF00\", \"00FF00\") == 0)"