enabled and fixed -Wcovered-switch-default Clang warnings

Makefile

@@ -625,7 +625,7 @@ $(libcppdir)/pathanalysis.o: lib/pathanalysis.cpp lib/astutils.h lib/config.h li
 $(libcppdir)/pathmatch.o: lib/pathmatch.cpp lib/config.h lib/path.h lib/pathmatch.h lib/standards.h
 	$(CXX) ${INCLUDE_FOR_LIB} $(CPPFLAGS) $(CXXFLAGS) -c -o $@ $(libcppdir)/pathmatch.cpp
 
-$(libcppdir)/platform.o: lib/platform.cpp externals/tinyxml2/tinyxml2.h lib/config.h lib/mathlib.h lib/path.h lib/platform.h lib/standards.h lib/xml.h
+$(libcppdir)/platform.o: lib/platform.cpp externals/tinyxml2/tinyxml2.h lib/config.h lib/mathlib.h lib/path.h lib/platform.h lib/standards.h lib/utils.h lib/xml.h
 	$(CXX) ${INCLUDE_FOR_LIB} $(CPPFLAGS) $(CXXFLAGS) -c -o $@ $(libcppdir)/platform.cpp
 
 $(libcppdir)/preprocessor.o: lib/preprocessor.cpp externals/simplecpp/simplecpp.h lib/addoninfo.h lib/checkers.h lib/config.h lib/errorlogger.h lib/errortypes.h lib/library.h lib/mathlib.h lib/path.h lib/platform.h lib/preprocessor.h lib/settings.h lib/standards.h lib/suppressions.h lib/utils.h
@@ -697,7 +697,7 @@ cli/executor.o: cli/executor.cpp cli/executor.h lib/addoninfo.h lib/checkers.h l
 cli/filelister.o: cli/filelister.cpp cli/filelister.h lib/config.h lib/filesettings.h lib/mathlib.h lib/path.h lib/pathmatch.h lib/platform.h lib/standards.h lib/utils.h
 	$(CXX) ${INCLUDE_FOR_CLI} $(CPPFLAGS) $(CXXFLAGS) -c -o $@ cli/filelister.cpp
 
-cli/main.o: cli/main.cpp cli/cppcheckexecutor.h lib/config.h lib/filesettings.h lib/mathlib.h lib/path.h lib/platform.h lib/standards.h
+cli/main.o: cli/main.cpp cli/cppcheckexecutor.h lib/config.h lib/filesettings.h lib/mathlib.h lib/path.h lib/platform.h lib/standards.h lib/utils.h
 	$(CXX) ${INCLUDE_FOR_CLI} $(CPPFLAGS) $(CXXFLAGS) -c -o $@ cli/main.cpp
 
 cli/processexecutor.o: cli/processexecutor.cpp cli/executor.h cli/processexecutor.h lib/addoninfo.h lib/check.h lib/checkers.h lib/config.h lib/cppcheck.h lib/errorlogger.h lib/errortypes.h lib/filesettings.h lib/library.h lib/mathlib.h lib/path.h lib/platform.h lib/settings.h lib/standards.h lib/suppressions.h lib/timer.h lib/utils.h

cmake/compileroptions.cmake

@@ -136,7 +136,6 @@ elseif(CMAKE_CXX_COMPILER_ID MATCHES "Clang")
     add_compile_options_safe(-Wno-unused-exception-parameter)
     add_compile_options_safe(-Wno-sign-conversion)
     add_compile_options_safe(-Wno-shadow-field-in-constructor)
-    add_compile_options_safe(-Wno-covered-switch-default)
     add_compile_options_safe(-Wno-shorten-64-to-32)
     add_compile_options_safe(-Wno-implicit-int-conversion)
     add_compile_options_safe(-Wno-double-promotion)

gui/checkstatistics.cpp

@@ -18,6 +18,8 @@
 
 #include "checkstatistics.h"
 
+#include "utils.h"
+
 #include <QDebug>
 #include <QList>
 #include <QSet>
@@ -59,7 +61,6 @@ void CheckStatistics::addItem(const QString &tool, ShowTypes::ShowType type)
         ::addItem(mInformation, lower);
         break;
     case ShowTypes::ShowNone:
-    default:
         qDebug() << "Unknown error type - not added to statistics.";
         break;
     }
@@ -99,10 +100,10 @@ unsigned CheckStatistics::getCount(const QString &tool, ShowTypes::ShowType type
     case ShowTypes::ShowInformation:
         return mInformation.value(lower,0);
     case ShowTypes::ShowNone:
-    default:
         qDebug() << "Unknown error type - returning zero statistics.";
         return 0;
     }
+    cppcheck::unreachable();
 }
 
 QStringList CheckStatistics::getTools() const

gui/mainwindow.cpp

@@ -1016,9 +1016,6 @@ bool MainWindow::tryLoadLibrary(Library &library, const QString& filename)
         case Library::ErrorCode::UNKNOWN_ELEMENT:
             errmsg = tr("Unknown element");
             break;
-        default:
-            errmsg = tr("Unknown issue");
-            break;
         }
         if (!error.reason.empty())
             errmsg += " '" + QString::fromStdString(error.reason) + "'";

gui/resultstree.cpp

@@ -32,6 +32,7 @@
 #include "showtypes.h"
 #include "suppressions.h"
 #include "threadhandler.h"
+#include "utils.h"
 #include "xmlreportv2.h"
 
 #include <algorithm>
@@ -377,9 +378,10 @@ QString ResultsTree::severityToTranslatedString(Severity severity)
         return tr("internal");
 
     case Severity::none:
-    default:
         return QString();
     }
+
+    cppcheck::unreachable();
 }
 
 ResultItem *ResultsTree::findFileItem(const QString &name) const

lib/platform.h

@@ -24,6 +24,7 @@
 #include "config.h"
 #include "mathlib.h"
 #include "standards.h"
+#include "utils.h"
 
 #include <cassert>
 #include <climits>
@@ -194,9 +195,8 @@ class CPPCHECKLIB Platform {
             return "unix64";
         case Type::File:
             return "platformFile";
-        default:
-            throw std::runtime_error("unknown platform");
         }
+        cppcheck::unreachable();
     }
 
     long long unsignedCharMax() const {

lib/symboldatabase.cpp

@@ -4065,9 +4065,8 @@ static const char* functionTypeToString(FunctionType type)
         return "Function";
     case FunctionType::eLambda:
         return "Lambda";
-    default:
-        return "Unknown";
     }
+    cppcheck::unreachable();
 }
 
 static std::string tokenToString(const Token* tok, const Tokenizer& tokenizer)

oss-fuzz/Makefile

@@ -305,7 +305,7 @@ $(libcppdir)/pathanalysis.o: ../lib/pathanalysis.cpp ../lib/astutils.h ../lib/co
 $(libcppdir)/pathmatch.o: ../lib/pathmatch.cpp ../lib/config.h ../lib/path.h ../lib/pathmatch.h ../lib/standards.h
 	$(CXX) ${LIB_FUZZING_ENGINE} $(CPPFLAGS) $(CXXFLAGS) -c -o $@ $(libcppdir)/pathmatch.cpp
 
-$(libcppdir)/platform.o: ../lib/platform.cpp ../externals/tinyxml2/tinyxml2.h ../lib/config.h ../lib/mathlib.h ../lib/path.h ../lib/platform.h ../lib/standards.h ../lib/xml.h
+$(libcppdir)/platform.o: ../lib/platform.cpp ../externals/tinyxml2/tinyxml2.h ../lib/config.h ../lib/mathlib.h ../lib/path.h ../lib/platform.h ../lib/standards.h ../lib/utils.h ../lib/xml.h
 	$(CXX) ${LIB_FUZZING_ENGINE} $(CPPFLAGS) $(CXXFLAGS) -c -o $@ $(libcppdir)/platform.cpp
 
 $(libcppdir)/preprocessor.o: ../lib/preprocessor.cpp ../externals/simplecpp/simplecpp.h ../lib/addoninfo.h ../lib/checkers.h ../lib/config.h ../lib/errorlogger.h ../lib/errortypes.h ../lib/library.h ../lib/mathlib.h ../lib/path.h ../lib/platform.h ../lib/preprocessor.h ../lib/settings.h ../lib/standards.h ../lib/suppressions.h ../lib/utils.h