http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48031
--- Comment #6 from rguenther at suse dot de <rguenther at suse dot de> 2011-03-10 09:33:49 UTC --- On Thu, 10 Mar 2011, mikpe at it dot uu.se wrote: > http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48031 > > --- Comment #5 from Mikael Pettersson <mikpe at it dot uu.se> 2011-03-10 > 09:22:04 UTC --- > If I revert this part of r139061 then things work again: > > * gimplify.c (gimplify_conversion): Use maybe_fold_offset_to_address. > > --- gcc/gimplify.c (revision 139060) > +++ gcc/gimplify.c (revision 139061) > @@ -1842,17 +1842,13 @@ gimplify_conversion (tree *expr_p) > /* Attempt to avoid NOP_EXPR by producing reference to a subtype. > For example this fold (subclass *)&A into &A->subclass avoiding > a need for statement. */ > - if (TREE_CODE (*expr_p) == NOP_EXPR > + if (CONVERT_EXPR_P (*expr_p) > && POINTER_TYPE_P (TREE_TYPE (*expr_p)) > && POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (*expr_p, 0))) > - && (tem = maybe_fold_offset_to_reference > + && (tem = maybe_fold_offset_to_address > (TREE_OPERAND (*expr_p, 0), > - integer_zero_node, TREE_TYPE (TREE_TYPE (*expr_p))))) > - { > - tree ptr_type = build_pointer_type (TREE_TYPE (tem)); > - if (useless_type_conversion_p (TREE_TYPE (*expr_p), ptr_type)) > - *expr_p = build_fold_addr_expr_with_type (tem, ptr_type); > - } > + integer_zero_node, TREE_TYPE (*expr_p))) != NULL_TREE) > + *expr_p = tem; > > /* If we still have a conversion at the toplevel, > then canonicalize some constructs. */ > > The first condition change is Ok, it's the change to call m_f_o_t_address > instead of m_f_o_t_reference and the then-clause change that matter. > > Reverting this from trunk @ r139061 + r151559 backport, or trunk @ r151559, > eliminates the ICE. I think this is all just the right circumstances for triggering the bug.
