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Full Version: Rule 5.4: Macro identifier
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I have a question regarding rule 5.4: Which of the following #defines is violating this rule?

#define  engine_exhaust_gas_temperature_high_raw     egt_r
#define  engine_exhaust_gas_temperature_high_scaled  egt_s

#define x 0
#define x 0

#ifndef ABCDE

#ifndef FGHIJ

unsigned long int A;
unsigned short int Con = 0;

void main(void)

    A = Con;
    A = x;

The 1st and 2nd #define are similar to the example given in the MISRA-C guideline. Hence, the 2nd #define violates the rule.
The 3rd and 4th #define are identical. Therefore, the 4th #define violates the rule.
The 5th and 6th #define are identical as well. Does the 6th #define violate the rule? According to the glossary, the macro name is a macro identifier...
The amplification states
Quote: This rule requires that, when a macro is being defined, its name be distinct from:
  • the names of the other macros that are currently defined;
Therefore there will only be a violation of Rule 5.4 on DAI_AGK_SEC_1BIT_RAM_START if both ABCDE and FGHIJ are not defined.