diff --git a/jerry-core/debugger/debugger-ws.h b/jerry-core/debugger/debugger-ws.h
index 63e5d3013..f3af65bb0 100644
--- a/jerry-core/debugger/debugger-ws.h
+++ b/jerry-core/debugger/debugger-ws.h
@@ -110,4 +110,4 @@ void jerry_debugger_compute_sha1 (const uint8_t *input1, size_t input1_len,
 
 #endif /* JERRY_DEBUGGER */
 
-#endif /* DEBUGGER_WS_H */
+#endif /* !DEBUGGER_WS_H */
diff --git a/jerry-core/debugger/debugger.h b/jerry-core/debugger/debugger.h
index c07687479..c59fba74c 100644
--- a/jerry-core/debugger/debugger.h
+++ b/jerry-core/debugger/debugger.h
@@ -356,4 +356,4 @@ bool jerry_debugger_send_exception_string (ecma_value_t exception_value);
 
 #endif /* JERRY_DEBUGGER */
 
-#endif /* DEBUGGER_H */
+#endif /* !DEBUGGER_H */
diff --git a/jerry-main/cli.h b/jerry-main/cli.h
index 43c65f896..f8f3836a2 100644
--- a/jerry-main/cli.h
+++ b/jerry-main/cli.h
@@ -73,4 +73,4 @@ const char * cli_consume_string (cli_state_t *state_p);
 int cli_consume_int (cli_state_t *state_p);
 void cli_help (const char *prog_name_p, const char *command_name_p, const cli_opt_t *options_p);
 
-#endif /* CLI_H */
+#endif /* !CLI_H */
diff --git a/tests/unit-core/test-common.h b/tests/unit-core/test-common.h
index 6200a8aa8..e9f2cdab5 100644
--- a/tests/unit-core/test-common.h
+++ b/tests/unit-core/test-common.h
@@ -68,4 +68,4 @@ do \
   srand (seed); \
 } while (0)
 
-#endif /* TEST_COMMON_H */
+#endif /* !TEST_COMMON_H */
diff --git a/tests/unit-ext/test-common.h b/tests/unit-ext/test-common.h
index 0254a0096..cf62d281c 100644
--- a/tests/unit-ext/test-common.h
+++ b/tests/unit-ext/test-common.h
@@ -33,4 +33,4 @@
     } \
   } while (0)
 
-#endif /* TEST_COMMON_H */
+#endif /* !TEST_COMMON_H */