Fortran: handle bad array ctors with typespec [PR93483, PR107216, PR107219]

Fortran: handle bad array ctors with typespec [PR93483, PR107216, PR107219]

gcc/fortran/ChangeLog:

	PR fortran/93483
	PR fortran/107216
	PR fortran/107219
	* arith.cc (reduce_unary): Handled expressions are EXP_CONSTANT and
	EXPR_ARRAY.  Do not attempt to reduce otherwise.
	(reduce_binary_ac): Likewise.
	(reduce_binary_ca): Likewise.
	(reduce_binary_aa): Moved check for EXP_CONSTANT and EXPR_ARRAY
	from here ...
	(reduce_binary): ... to here.
	(eval_intrinsic): Catch failed reductions.
	* gfortran.h (GFC_INTRINSIC_OPS): New enum ARITH_NOT_REDUCED to keep
	track of expressions that were not reduced by the arithmetic evaluation
	code.

gcc/testsuite/ChangeLog:

	PR fortran/93483
	PR fortran/107216
	PR fortran/107219
	* gfortran.dg/array_constructor_56.f90: New test.
	* gfortran.dg/array_constructor_57.f90: New test.

Co-authored-by: Mikael Morin <mikael@gcc.gnu.org>