Re: egcs-20000306 ICE in `size_binop', at fold-const.c:1873

[Mark Mitchell <mark at codesourcery dot com>]

>>>>> "grahams" == grahams  <grahams@rcp.co.uk> writes:

    grahams> Mark

    grahams> Here's a patch but I'm not sure if it's technically
    grahams> correct.

I don't know either.  But I hope not.

In get_inner_reference, offset is initialized to size_zero_node.  It's
never assigned to, except as the result of `size_binop'.  And, yet, it
ends up not having sizetype, do to oddness in `fold'.  Surely, if we
just keep calling size_binop, and passing the result back to
size_binop, we should not have to explicitly convert to size_type
between each call.  So, either size_binop should convert its result,
or `fold' should not be doing what it's doing.

What's odd here is that sizetype is an unsigned type, and yet you've
found a place where offset is quite reasonably negative.  The fix
might be that get_inner_reference should use integer_type, rather that
sizetype.

I hope Kenner will fix the bug, since he's been working on this stuff
lately, and has the clearest sense of his own intentions.

Thanks for the patch,

--
Mark Mitchell                   mark@codesourcery.com
CodeSourcery, LLC               http://www.codesourcery.com