Re: how to initialize union?

Re: how to initialize union?

[Deepen Mantri]

>>union my_union {
>>  struct {
>>    int a;
>>    int b;
>>  };
>>  struct {
>>    char a;
>>    short b;
>>    void *c;
>>  } v;
>>};

>>And I want to initialize 2 global variables, of `my_union' type,
>>A and B to:
>>------------------------------------
>>A.a=1; A.b=2;
>>B.v.a='a'; B.v.b=16; B.v.c=NULL;
>>------------------------------------
>>I know how to initialize A by:
>>union my_union A = { 1, 2 };
>>But I don't know how to write the initializers for B.
>>Can gcc support this feature?


The union variable can be initialized with the help of,
union my_union B = {.v = {'a',16,NULL}};


Regards,
Deepen Mantri
KPIT Cummins InfoSystems Ltd.
Pune, India

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Re: how to initialize union?

[Eus]

PRC wrote:

> union my_union {
>   struct {
>     int a;
>     int b;
>   };
>   struct {
>     char a;
>     short b;
>     void *c;
>   } v;
> };
>
> And I want to initialize 2 global variables, of `my_union' type, A and B to:
> ------------------------------------
> A.a=1; A.b=2;
> B.v.a='a'; B.v.b=16; B.v.c=NULL;
> ------------------------------------
> I know how to initialize A by:
> union my_union A = { 1, 2 };
>
> But I don't know how to write the initializers for B.
> Can gcc support this feature?

union my_union B = {
        .v.a = 'a',
        .v.b = 16,
        .v.c = NULL
};

will do the job.

Best regards,
Eus (FSF member #4445)

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how to initialize union?

[PRC]

union my_union {
  struct {
    int a;
    int b;
  };
  struct {
    char a;
    short b;
    void *c;
  } v;
};

And I want to initialize 2 global variables, of `my_union' type, A and B to:
------------------------------------
A.a=1; A.b=2;
B.v.a='a'; B.v.b=16; B.v.c=NULL;
------------------------------------
I know how to initialize A by:
union my_union A = { 1, 2 };

But I don't know how to write the initializers for B.
Can gcc support this feature?