[Bug c++/89224] [9/10/11/12 Regregression] subscript of const vector has the wrong type

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89224

--- Comment #5 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Here is another testcase which should be rejected, this time C++11 (rather than
C++98).
typedef __attribute__((vector_size(16))) unsigned char  __Int8x8_t;

void f(const __Int8x8_t x) {
  decltype(x[0]) a = x[0];
  a = 1;
}