build: Enable -Wunreachable-code

configure.ac

@@ -446,8 +446,8 @@ if test "$CXXFLAGS_overridden" = "no"; then
   AX_CHECK_COMPILE_FLAG([-Wlogical-op], [WARN_CXXFLAGS="$WARN_CXXFLAGS -Wlogical-op"], [], [$CXXFLAG_WERROR])
   AX_CHECK_COMPILE_FLAG([-Woverloaded-virtual], [WARN_CXXFLAGS="$WARN_CXXFLAGS -Woverloaded-virtual"], [], [$CXXFLAG_WERROR])
   AX_CHECK_COMPILE_FLAG([-Wsuggest-override], [WARN_CXXFLAGS="$WARN_CXXFLAGS -Wsuggest-override"], [], [$CXXFLAG_WERROR])
-  AX_CHECK_COMPILE_FLAG([-Wunreachable-code-loop-increment], [WARN_CXXFLAGS="$WARN_CXXFLAGS -Wunreachable-code-loop-increment"], [], [$CXXFLAG_WERROR])
   AX_CHECK_COMPILE_FLAG([-Wimplicit-fallthrough], [WARN_CXXFLAGS="$WARN_CXXFLAGS -Wimplicit-fallthrough"], [], [$CXXFLAG_WERROR])
+  AX_CHECK_COMPILE_FLAG([-Wunreachable-code], [WARN_CXXFLAGS="$WARN_CXXFLAGS -Wunreachable-code"], [], [$CXXFLAG_WERROR])
 
   if test "$suppress_external_warnings" != "no" ; then
     AX_CHECK_COMPILE_FLAG([-Wdocumentation], [WARN_CXXFLAGS="$WARN_CXXFLAGS -Wdocumentation"], [], [$CXXFLAG_WERROR])

src/wallet/walletdb.cpp

@@ -1499,17 +1499,19 @@ std::unique_ptr<WalletDatabase> MakeDatabase(const fs::path& path, const Databas
     if (format == DatabaseFormat::SQLITE) {
 #ifdef USE_SQLITE
         return MakeSQLiteDatabase(path, options, status, error);
-#endif
+#else
         error = Untranslated(strprintf("Failed to open database path '%s'. Build does not support SQLite database format.", fs::PathToString(path)));
         status = DatabaseStatus::FAILED_BAD_FORMAT;
         return nullptr;
+#endif
     }
 
 #ifdef USE_BDB
     return MakeBerkeleyDatabase(path, options, status, error);
-#endif
+#else
     error = Untranslated(strprintf("Failed to open database path '%s'. Build does not support Berkeley DB database format.", fs::PathToString(path)));
     status = DatabaseStatus::FAILED_BAD_FORMAT;
     return nullptr;
+#endif
 }
 } // namespace wallet