[Bug fortran/107680] ICE in arith_power, at fortran/arith.cc:989 and :1006

["anlauf at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107680

--- Comment #4 from anlauf at gcc dot gnu.org ---
(In reply to Mikael Morin from comment #3)
> I thought the call to gfc_type_convert_binary in eval_intrinsic was taking
> care of mismatching types, doesn't it?

It does, and then it doesn't do it sometimes...

For

  real, parameter :: x(*) = [real :: ([1])]   **  2.0

after adding breakpoints in gfc_type_convert_binary and arith_power,
I see correct types in the former (e->value.op.op2->ts.type = BT_REAL)
but incorrect types in the latter (op1->ts.type = BT_INTEGER).

It seems to be the ratatouille of parentheses, array constructors,
typespec, and arithmetic operation that is crucial to get this type
of error.

In 12-branch, I also see other bad things happening, which I believe have
partially been fixed by the series of patches for pr107000 and friends.
Try:

  print *, [integer :: ([3.0])] **  2.0

This gives

0.00000000

for all versions <= 12, and

9.00000000

for mainline.

Given these observations, I suspect that typespecs are not consistently
handled...  See also the previous discussions.