In a function declaration, what does passing a fixed size array signify? [duplicate]

Answer 1

In a one dimensional array It has no significance and is ignored by the compiler. In a two or more dimensional array It can be useful and is used by the function as a way to determine the row length of the matrix(or multi dimensional array). for example :

int 2dArr(int arr[][10]){
   return arr[1][2];
}

this function would know the address of arr[1][2] according to the specified length, and also the compiler should not accept different sizes of arrays for this function -

int arr[30][30];
2dArr(arr);

is not allowed and would be a compiler error(g++) :

error: cannot convert int (*)[30] to int (*)[10]