C++: Internal compiler error

[Mark Mitchell]

  Index: decl.c
  ===================================================================
  RCS file: /cvs/gcc/egcs/gcc/cp/decl.c,v
  retrieving revision 1.594
  diff -u -p -r1.594 decl.c
  --- decl.c	2000/04/24 06:41:16	1.594
  +++ decl.c	2000/04/24 12:20:55
  @@ -10351,6 +10351,17 @@ grokdeclarator (declarator, declspecs, d

	      declarator = TREE_OPERAND (declarator, 0);

  +	    /* VLAs never work as fields. */
  +	    if (decl_context == FIELD && size != NULL_TREE
  +		&& !processing_template_decl
  +		&& !TREE_CONSTANT (cp_convert (sizetype, size)))
  +	      {
  +		cp_error ("size of member `%D' is not constant", dname);
  +		/* Proceed with arbitrary constant size, so that offset
  +		   computations don't get confused. */
  +		size = integer_one_node;
  +	      }
  +

I'm not sure this is quite good enough.  Either it isn't, or
compute_array_index_type is doing a lot more work than it needs to!
For instance, does this handle `const int I = 7' as an array bound?
Similarly `(int) (int) I'?  

By the way, why does compute_array_index_type convert the argument to
ssizetype?  Array index types would seem more naturally unsigned to
me.  And what if the original bound had type `long long'?  Aren't we
then truncating the array?

I wonder if you shouldn't check for this problem later in the game,
after the array type is created a few lines below your patch.  Then,
all you have to do is check that the TYPE_DOMAIN is TREE_CONSTANT, and
fix up the type (for error-reporting purposes) if not.

--
Mark Mitchell                   mark@codesourcery.com
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