add comment + unreachable

Author: ludviggunne

lib/errorlogger.cpp

@@ -948,6 +948,7 @@ std::string getClassification(const std::string &guideline, ReportType reportTyp
     case ReportType::misraC2012:
     case ReportType::misraC2023:
     case ReportType::misraC2025:
+    /* NOTE: If you add another report type here, remember to update the inner switch as well. */
     {
         const bool isDirective = guideline.rfind("Dir ", 0) == 0;
 
@@ -971,6 +972,7 @@ std::string getClassification(const std::string &guideline, ReportType reportTyp
             info = isDirective ? &checkers::misraC2025Directives : &checkers::misraC2025Rules;
             break;
         default:
+            cppcheck::unreachable();
             break;
         }