Fix warnings

Author: glankk

simplecpp.cpp

@@ -4032,6 +4032,7 @@ const char *simplecpp::getCStdName(cstd_t std)
     case C23: return "C23";
     case C2Y: return "C2Y";
     }
+    return "";
 }
 
 std::string simplecpp::getCStdString(cstd_t std)
@@ -4098,6 +4099,7 @@ const char *simplecpp::getCppStdName(cppstd_t std)
     case CPP23: return "C++23";
     case CPP26: return "C++26";
     }
+    return "";
 }
 
 std::string simplecpp::getCppStdString(cppstd_t std)

test.cpp

@@ -2909,7 +2909,7 @@ static void lineDirective()
         }
     }
 
-    for (const std::string std : {"c99", "c++11", "c++14", "c++17", "c++20", "c++23"}) {
+    for (const std::string std : {"c99", "c11", "c17", "c23", "c2y", "c++11", "c++14", "c++17", "c++20", "c++23"}) {
         std::string std_name;
         if (simplecpp::getCStd(std) != simplecpp::CUnknown)
             std_name = simplecpp::getCStdName(simplecpp::getCStd(std));