gcc/doc/gcc/extensions-to-the-c-language-family/pointers-to-arrays-with-qualifiers-work-as-expected.rst

   1 ..
   2   Copyright 1988-2022 Free Software Foundation, Inc.
   3   This is part of the GCC manual.
   4   For copying conditions, see the copyright.rst file.
   5
   6 .. index:: pointers to arrays, const qualifier
   7
   8 .. _pointers-to-arrays:
   9
  10 Pointers to Arrays with Qualifiers Work as Expected
  11 ***************************************************
  12
  13 In GNU C, pointers to arrays with qualifiers work similar to pointers
  14 to other qualified types. For example, a value of type ``int (*)[5]``
  15 can be used to initialize a variable of type ``const int (*)[5]``.
  16 These types are incompatible in ISO C because the ``const`` qualifier
  17 is formally attached to the element type of the array and not the
  18 array itself.
  19
  20 .. code-block:: c++
  21
  22   extern void
  23   transpose (int N, int M, double out[M][N], const double in[N][M]);
  24   double x[3][2];
  25   double y[2][3];
  26   ...
  27   transpose(3, 2, y, x);