constant elements vs. constant array

Question

Everybody knows how to declare an array with constant elements:

const int a[10];

Apparently, it is also possible to declare an array that is itself constant, via a typedef:

typedef int X[10];
const X b;

From a technical and a practical standpoint, do a and b have the same type or different types?

Answer 1

Apparently, it is also possible to declare an array that is itself constant

Nope. In N1256, §6.7.3/8:

If the specification of an array type includes any type qualifiers, the element type is so-qualified, not the array type.¹¹⁸⁾

Then footnote 118 says:

Both of these can occur through the use of typedefs.

Answer 2

They have the same type, though clang will print them differently. Since the array itself cannot be const, it is said to "fall through".

For the non-typedefed version, clang prints the type as const int [10]. For the typedef version, it prints int const[10]. Both of those are equivalent.

Coliru in action.