Will the string initializer lose some memory?

Question

To initialize a char array, I usually write:

char string[] = "some text";

But today, one of my classmates said that I should use:

char string[] = {'s', 'o', 'm', 'e', ' ', 't', 'e', 'x', 't', '\0'};

I told him that it was crazy to give up readability and brevity, but he claimed that initializing a char array with a string would actually create two lines, one of them on the stack and the other in read-only memory. When working with embedded devices, this can lead to unacceptable memory waste.

Of course, line initializers seem clearer, so I will use them in my programs. But the question is, will the line initializer create two identical lines? Or are string initializers just syntactic sugars?

Answer 1

char string[] = "some text";

100% equivalent

char string[] = {'s', 'o', 'm', 'e', ' ', 't', 'e', 'x', 't', '\0'};

Your friend is confused: if string- a local variable, then in both cases you create two lines. Your variable string, which is on the stack, and the read-only string literal, which is in read-only memory ( .rodata).

There is no way to avoid read-only storage, as all data must be placed somewhere. You cannot select string literals in the air. All you can do is move it from one read-only memory segment to another, which will ultimately give you the same program size.

The first style is preferable because it is more readable. It is truly a form of syntactic sugar.

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