What do array initialisers return?

Question

What do array initialisers such as { 'a', 'b', 'c' } return? My understanding is that using an initialiser allocates contiguous memory blocks and return the address to the first block.

The following code doesn't work:

char *char_ptr_1 = { 'a', 'b', 'c', '\0' };

On the other hand, this is seems to work fine:

char char_array[] = { 'a', 'b', 'c', '\0' };
char *char_ptr_2 = char_array;

char_array stores the address to the first memory block which explains why I am able to assign the value of char_array to chat_ptr_2. Does C convert the value returned by the initialiser to something which can be stored in a pointer?

I did look online and and found a couple of answers which talked about the difference between arrays and pointers but they didn't help me.

Answer 1

Initializers do not return anything per se. They give the compiler directions as to what to put into the item being declared - in this case, they tell the compiler what to put into elements of an array.

That is why you cannot assign an initializer to a pointer: an array initializer needs to be paired with an array to make sense to the compiler.

A pointer can be initialized with a pointer expression. That is why the initialization in your

char *char_ptr_2 = char_array;

declaration works: the compiler converts char_array to a pointer, and initializes char_ptr_2 with it.

Answer 2

it's called array initializer, because it initalizes an array and not a pointer.

It's simply C syntax, why the pointer option is not allowed.

Answer 3

They are array initializers, not normal expressions that have a value. I. e., an array initializer can only be used to initialize an array. It is a special bit of syntax for a specific use, end of the story.