Rule 19.1 and assigment between members of a struct

Rule 19.1 and assigment between members of a struct - Printable Version

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Rule 19.1 and assigment between members of a struct - GerlindeKettl - 20-11-2015

Does this code violate rule 19.1?

Code:
struct s_tag {  

uint8 ReadPos;

uint8 WritePos; }; 

typedef struct s_tag s;

union u_tag { 

s      Elements;

uint32 Value; }; 

typedef union u_tag u; 

u NewState;

NewState.Elements.ReadPos  = NewState.Elements.WritePos;

My static code checker thinks it is a violation, but from my point of view I'm just assigning one member of a struct to a different member of the struct and they don't overlap in memory. That this struct is a member of a union should not matter as there is no assignment across the members of the union.

Re: Rule 19.1 and assigment between members of a struct - misra-c - 11-12-2015

Your code is compliant with rule 19.1, though will violate rule 19.2.