[Bug fortran/68566] ICE on using unusable array in reshape (double free or corruption)

[anlauf at gmx dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68566

Harald Anlauf <anlauf at gmx dot de> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |anlauf at gmx dot de

--- Comment #5 from Harald Anlauf <anlauf at gmx dot de> ---
(In reply to Gerhard Steinmetz from comment #4)
> Simplified a bit :
> 
> 
> $ cat z7.f90
> program p
>    integer, parameter :: a(:) = 1
>    integer, parameter :: b(2,2) = reshape([a], [2,2])
> end

This is caught by the following trivial patch:

Index: gcc/fortran/simplify.c
===================================================================
--- gcc/fortran/simplify.c      (revision 234170)
+++ gcc/fortran/simplify.c      (working copy)
@@ -5163,6 +5163,9 @@
       || !is_constant_array_expr (order_exp))
     return NULL;

+  if (source->shape == NULL)
+    return NULL;
+
   /* Proceed with simplification, unpacking the array.  */

   mpz_init (index);


% gfc-trunk pr68566.f90
pr68566.f90:3:28:

   integer, parameter :: a(:) = 1
                            1
Error: Parameter array 'a' at (1) cannot be automatic or of deferred shape


Caveat: not regtested.
Somebody please check whether the above makes sense.