diff --git a/include/rapidjson/reader.h b/include/rapidjson/reader.h
index 43b2d9c6e..18c4ca558 100644
--- a/include/rapidjson/reader.h
+++ b/include/rapidjson/reader.h
@@ -109,7 +109,7 @@ RAPIDJSON_DIAG_OFF(effc++)
 #define RAPIDJSON_PARSE_ERROR(parseErrorCode, offset) \
     RAPIDJSON_MULTILINEMACRO_BEGIN \
     RAPIDJSON_PARSE_ERROR_NORETURN(parseErrorCode, offset); \
-    return RAPIDJSON_NOTHING; \
+    RAPIDJSON_PARSE_ERROR_EARLY_RETURN_VOID; \
     RAPIDJSON_MULTILINEMACRO_END
 #endif
 
@@ -1387,13 +1387,13 @@ class GenericReader {
         }
         
         switch (src) {
-        case IterativeParsingStartState:            RAPIDJSON_PARSE_ERROR(kParseErrorDocumentEmpty, is.Tell());
-        case IterativeParsingFinishState:           RAPIDJSON_PARSE_ERROR(kParseErrorDocumentRootNotSingular, is.Tell());
+        case IterativeParsingStartState:            RAPIDJSON_PARSE_ERROR(kParseErrorDocumentEmpty, is.Tell()); return;
+        case IterativeParsingFinishState:           RAPIDJSON_PARSE_ERROR(kParseErrorDocumentRootNotSingular, is.Tell()); return;
         case IterativeParsingObjectInitialState:
-        case IterativeParsingMemberDelimiterState:  RAPIDJSON_PARSE_ERROR(kParseErrorObjectMissName, is.Tell());
-        case IterativeParsingMemberKeyState:        RAPIDJSON_PARSE_ERROR(kParseErrorObjectMissColon, is.Tell());
-        case IterativeParsingMemberValueState:      RAPIDJSON_PARSE_ERROR(kParseErrorObjectMissCommaOrCurlyBracket, is.Tell());
-        case IterativeParsingElementState:          RAPIDJSON_PARSE_ERROR(kParseErrorArrayMissCommaOrSquareBracket, is.Tell());
+        case IterativeParsingMemberDelimiterState:  RAPIDJSON_PARSE_ERROR(kParseErrorObjectMissName, is.Tell()); return;
+        case IterativeParsingMemberKeyState:        RAPIDJSON_PARSE_ERROR(kParseErrorObjectMissColon, is.Tell()); return;
+        case IterativeParsingMemberValueState:      RAPIDJSON_PARSE_ERROR(kParseErrorObjectMissCommaOrCurlyBracket, is.Tell()); return;
+        case IterativeParsingElementState:          RAPIDJSON_PARSE_ERROR(kParseErrorArrayMissCommaOrSquareBracket, is.Tell()); return;
         default:                                    RAPIDJSON_PARSE_ERROR(kParseErrorUnspecificSyntaxError, is.Tell());
         }       
     }
diff --git a/test/unittest/CMakeLists.txt b/test/unittest/CMakeLists.txt
index fb95b8e36..fd2eb4d1f 100644
--- a/test/unittest/CMakeLists.txt
+++ b/test/unittest/CMakeLists.txt
@@ -21,7 +21,7 @@ set(UNITTEST_SOURCES
 if ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU")
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Werror -Wall -Wextra -Weffc++ -Wswitch-default -Wfloat-equal")
 elseif (CMAKE_CXX_COMPILER_ID MATCHES "Clang")
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Werror -Wall -Wextra -Weffc++ -Wswitch-default -Wfloat-equal")
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Werror -Wall -Wextra -Weffc++ -Wswitch-default -Wfloat-equal -Wimplicit-fallthrough")
 elseif ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "MSVC")
     add_definitions(-D_CRT_SECURE_NO_WARNINGS=1)
 endif()