cvariable-length-arrayarray-initialization

Initializing variable length array

On initializing a Variable length array compiler gives an error message: 

[Error] variable-sized object may not be initialized

Code snippet:

int n; 
printf("Enter size of magic square: ");
scanf("%d",&n);

int board[n][n] = {0};

How should Variable Length arrays be initialized? And why it's all elements are not initialized to 0 in the way give below;

   int board[n][n];
   board[n][n] = {0};

?

Solution

  • VLAs cannot be initialized by any form of initialization syntax. You have to assign the initial values to your array elements after the declaration in whichever way you prefer.

    C11: 6.7.9 Initialization (p2 and p3):

    No initializer shall attempt to provide a value for an object not contained within the entity being initialized.

    The type of the entity to be initialized shall be an array of unknown size or a complete object type that is not a variable length array type.