Additional Rules

Include Guard

Include guards shall prevent code from being processed multiple times which would cause compilation errors.
The following format shall be used:
#ifndef GUARD_<UUID>
#define GUARD_<UUID>
// ...
#endif // GUARD_<UUID>

The <UUID> shall be:

<8 hex digits>_<4 hex digits>_<4 hex digits>_<4 hex digits>_<12 hex digits>

The hex digits shall be uppercase.

good example
#ifndef GUARD_C73C2C69_6A11_4490_93AA_73A40D5F62F9
#define GUARD_C73C2C69_6A11_4490_93AA_73A40D5F62F9
// ...
#endif // GUARD_C73C2C69_6A11_4490_93AA_73A40D5F62F9
bad examples
#ifndef CANTRANSCEIVER_H_
#define CANTRANSCEIVER_H_
// ...
#endif /* CANTRANSCEIVER_H_ */

#ifndef HE793FCD8_FC04_45D3_A438_533341BBA7B1
#define HE793FCD8_FC04_45D3_A438_533341BBA7B1
// ...
#endif