http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53433
--- Comment #25 from Richard Guenther <rguenth at gcc dot gnu.org> 2012-07-04
11:26:55 UTC ---
Or the insn_data initializer does not properly point to the operand_data
initializer (maybe that is non-existent or the magic LTO error_mark_node
and we fold that in a wrong way - VOIDmode happens to be zero after all...).
See the special code in get_base_constructor in gimple-fold.c:
/* See if we can find constructor defining value of BASE.
When we know the consructor with constant offset (such as
base is array[40] and we do know constructor of array), then
BIT_OFFSET is adjusted accordingly.
As a special case, return error_mark_node when constructor
is not explicitly available, but it is known to be zero
such as 'static const int a;'. */
static tree
get_base_constructor (tree base, HOST_WIDE_INT *bit_offset,
tree (*valueize)(tree))
...
switch (TREE_CODE (base))
{
case VAR_DECL:
if (!const_value_known_p (base))
return NULL_TREE;
/* Fallthru. */
case CONST_DECL:
if (!DECL_INITIAL (base)
&& (TREE_STATIC (base) || DECL_EXTERNAL (base)))
return error_mark_node;
return DECL_INITIAL (base);
and lto-streamer-out.c:
/* Write a physical representation of tree node EXPR to output block
OB. If REF_P is true, the leaves of EXPR are emitted as references
via lto_output_tree_ref. IX is the index into the streamer cache
where EXPR is stored. */
static void
lto_write_tree (struct output_block *ob, tree expr, bool ref_p)
{
...
/* Handle DECL_INITIAL for symbols. */
tree initial = DECL_INITIAL (expr);
if (TREE_CODE (expr) == VAR_DECL
&& (TREE_STATIC (expr) || DECL_EXTERNAL (expr))
&& initial)
{
lto_varpool_encoder_t varpool_encoder;
struct varpool_node *vnode;
varpool_encoder = ob->decl_state->varpool_node_encoder;
vnode = varpool_get_node (expr);
if (!vnode
|| !lto_varpool_encoder_encode_initializer_p (varpool_encoder,
vnode))
initial = error_mark_node;
So, does
Index: gimple-fold.c
===================================================================
--- gimple-fold.c (revision 189251)
+++ gimple-fold.c (working copy)
@@ -2713,6 +2713,8 @@ get_base_constructor (tree base, HOST_WI
if (!DECL_INITIAL (base)
&& (TREE_STATIC (base) || DECL_EXTERNAL (base)))
return error_mark_node;
+ if (DECL_INITIAL (base) == error_mark_node)
+ return NULL_TREE;
return DECL_INITIAL (base);
case ARRAY_REF:
fix it?
