Return structure with flexible array member

Question

I need to return a structure with a flexible array member from a C function but can\'t figure out why it doesn\'t compile. I know that returning arrays can be achieved by en

Answer 1

Structs with flexible array members like yours (where the size of data is not given in the struct definition) are to be allocated like that:

struct data_array *a;   // pointer!!
a = malloc( sizeof(struct data_array) + 1000 * sizeof(double) );

Where sizeof(struct data_array) is the constant size of your struct excluding data and 1000 is the desired array size. Of course changing data to be a pointer and allocating it seperately will also work, but that is something slightly different.