[PATCH] fortran: support .NIL. in conditional arguments

[Steve Kargl]

On Mon, Oct 20, 2025 at 12:48:13PM +0200, Tobias Burnus wrote:
> Yuao Ma wrote:
> > This patch introduces support for the NIL value within conditional
> > arguments, addressing several scenarios for how NIL should be handled.
> 
> Let's start with two testcases that fail:
> 
> (A) Passing a string argument
> 
> I found a test that fails with an ICE (segmentation fault)
> in generic_simplify_COND_EXPR, called by gfc_conv_conditional_expr:
> 
> implicit none
> interface
>   subroutine sub(x)
>     character(*), optional :: x
>   end
> end interface
> logical :: cc
> call sub( (cc ? "132" : .nil.))
> end

I don't have the patch installed, so cannot directly test;
but, the above is technically a invalid program.  'cc' is
referenced but never defined.  I would expect a warning
with -Wall and an ICE is possible as  'cc' can be using
whatever is in memory.

-- 
steve