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Strict anti-aliasing with respect to population or types of union

I am trying to understand the implications of the following statement in C99 (C99; ISO / IEC 9899: 1999 6.5 / 7)

The object must have a stored value, accessible only with the value of the lvalue expression, which has one of the following types 73) or 88):

  • (other statements not related to the question are omitted)

  • an aggregate or union type that includes one of the above types among its members (including, recursively, a subaggregate member or contains union)

Consider the following:

typedef struct MyComplex {
    float real;
    float imag;
} MyComplex;

MyComplex *carray = malloc(sizeof(*carray) * 10);
float *as_floats = (float *)carray;

Is this legal since the structure MyComplexcontains a compatible type floatfor a pointer as_floats?

What about the other way? i.e:

float *farray = malloc(sizeof(*farray) * 10);
MyComplex *as_complex = (MyComplex *)farray;

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// issue 1 : problem with bitFields
typedef struct MyComplex_1 {
    unsigned int real : 1;
    unsigned int imag : 2;
} MyComplex_1;

// issue 2 : problem with members forced alignment
typedef struct MyComplex_2 {
    unsigned int real;
    unsigned int imag;
} __attribute__ ((aligned (64))) MyComplex_2; // GCC compiler directive

int main()
{
    MyComplex_1 arr_1[] = {{1, 2}, {1, 2}};
    MyComplex_2 arr_2[] = {{1, 2}, {1, 2}};

    int i;

    // for bitfield issue
    for (i=0; i<2; i++)
        printf("struct (%d,%d)\n", arr_1[i].real, arr_1[i].imag);

    for (i=0; i<4; i++)
        printf("var (%d)\n", ((unsigned int*)arr_1)[i]);

    // for struct member forced alignement issue
    for (i=0; i<2; i++)
        printf("struct (%d,%d)\n", arr_2[i].real, arr_2[i].imag);

    for (i=0; i<4; i++)
        printf("var (%d)\n", ((unsigned int*)arr_2)[i]);

    return 0;
}

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/* 1 */
carray[n].real

/* 2 */
asfloats[n * 2]

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