Re: [Patch, Fortran] PR41600 - fix ICE with type conversion in default initializer

[Tobias Burnus <burnus at net-b dot de>]

Tobias Burnus wrote:
> the middle end does not like to fold_convert a real number to an 
> integer, but gfortran does not type-convert the expressions of 
> initialization expressions. This patch fixes the issue

And Tobias Schlüter wrote in the PR:
> (In reply to comment #3)
> > +         if (comp->ts.type != comp->initializer->ts.type
> > +             || comp->ts.kind != comp->initializer->ts.kind)
> > +           gfc_convert_type_warn (ctor->expr,&comp->ts, 2, false);
> > +       }
> Isn't gfc_compare_types() more appropriate or are derived types not allowed?

Well, the function gfc_default_initializer should only be reachable if 
the LHS and the RHS are type compatible. While, "integer = 4.8" and 
"real = cmplx(1.0, 3.0)" are possible, you cannot have  "type(t2) :: x = 
t1()". Thus, I sincerely hope that such incompatible types are diagnosed 
before. Hence, doing this simple test should be sufficient.

* * *

Having said that, the following program compiles without any error - 
until one tries to use "my_t". (Now filled as PR51945.)

type t
  integer :: i = 3
end type t

type, extends(t) ::  t2
end type t2

type ::  t3
  integer :: i = 78
end type t3

type my_t
  type(t) :: x = t() ! OK
  type(t) :: y = t2() ! Invalid
  type(t) :: z = t3() ! Invalid
end type my_t

! type(my_t) :: a
end

Tobias