Hi!
As mentioned in the PR, if e.g. build_aligned_type creates some specially
aligned variant of some TYPE_MAIN_VARIANT, that type doesn't appear in the
IL during free_lang_data and later on we call build_aligned_type with the
same arguments as before, we'll get the previously created aligned variant
which has not been free_lang_data processed and during LTO streaming we ICE
because of that.
The following patch prunes unmarked types from the type variant chain, so
that we don't find them later on and instead create new type variants from
the free_lang_data processed types.
Another change is just to be sure, marking TYPE_CANONICAL if it is not
already marked, so that we don't get weird behavior if we'd remove it.
In the usual case TYPE_CANONICAL will be the TYPE_MAIN_VARIANT type we mark
already anyway.
The rest of the changes is to make sure the new types we create during
free_lang_data get marked in the pset, so that we will not try to purge
them.
Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
2019-03-20 Jan Hubicka <hubi...@ucw.cz>
Jakub Jelinek <ja...@redhat.com>
PR lto/89692
* tree.c (fld_type_variant): Call fld->pset.add.
(fld_incomplete_type_of): Likewise and don't call add_tree_to_fld_list
if it returns true.
(fld_process_array_type): Likewise.
(free_lang_data_in_type): Purge non-marked types from TYPE_NEXT_VARIANT
list.
(find_decls_types_r): Call fld_worklist_push for TYPE_CANONICAL (t).
* g++.dg/other/pr89692.C: New test.
--- gcc/tree.c.jj 2019-03-20 12:24:56.443322228 +0100
+++ gcc/tree.c 2019-03-20 20:16:12.277091827 +0100
@@ -5215,6 +5215,7 @@ fld_type_variant (tree first, tree t, st
if (inner_type)
TREE_TYPE (v) = inner_type;
gcc_checking_assert (fld_type_variant_equal_p (t,v, inner_type));
+ fld->pset.add (v);
add_tree_to_fld_list (v, fld);
return v;
}
@@ -5253,7 +5254,8 @@ fld_process_array_type (tree t, tree t2,
array = build_array_type_1 (t2, TYPE_DOMAIN (t),
TYPE_TYPELESS_STORAGE (t), false);
TYPE_CANONICAL (array) = TYPE_CANONICAL (t);
- add_tree_to_fld_list (array, fld);
+ if (!fld->pset.add (array))
+ add_tree_to_fld_list (array, fld);
}
return array;
}
@@ -5298,7 +5300,8 @@ fld_incomplete_type_of (tree t, struct f
TYPE_REF_CAN_ALIAS_ALL (t));
gcc_assert (TYPE_CANONICAL (t2) != t2
&& TYPE_CANONICAL (t2) == TYPE_CANONICAL (TREE_TYPE (t)));
- add_tree_to_fld_list (first, fld);
+ if (!fld->pset.add (first))
+ add_tree_to_fld_list (first, fld);
return fld_type_variant (first, t, fld);
}
return t;
@@ -5321,6 +5324,7 @@ fld_incomplete_type_of (tree t, struct f
copy = build_distinct_type_copy (t);
/* It is possible that type was not seen by free_lang_data yet. */
+ fld->pset.add (copy);
add_tree_to_fld_list (copy, fld);
TYPE_SIZE (copy) = NULL;
TYPE_USER_ALIGN (copy) = 0;
@@ -5445,6 +5449,18 @@ free_lang_data_in_type (tree type, struc
TYPE_NEEDS_CONSTRUCTING (type) = 0;
+ /* Purge non-marked variants from the variants chain, so that they
+ don't reappear in the IL after free_lang_data. */
+ while (TYPE_NEXT_VARIANT (type)
+ && !fld->pset.contains (TYPE_NEXT_VARIANT (type)))
+ {
+ tree t = TYPE_NEXT_VARIANT (type);
+ TYPE_NEXT_VARIANT (type) = TYPE_NEXT_VARIANT (t);
+ /* Turn the removed types into distinct types. */
+ TYPE_MAIN_VARIANT (t) = t;
+ TYPE_NEXT_VARIANT (t) = NULL_TREE;
+ }
+
if (TREE_CODE (type) == FUNCTION_TYPE)
{
TREE_TYPE (type) = fld_simplified_type (TREE_TYPE (type), fld);
@@ -5464,6 +5480,7 @@ free_lang_data_in_type (tree type, struc
& ~TYPE_QUAL_CONST
& ~TYPE_QUAL_VOLATILE;
TREE_VALUE (p) = build_qualified_type (arg_type, quals);
+ fld->pset.add (TREE_VALUE (p));
free_lang_data_in_type (TREE_VALUE (p), fld);
}
/* C++ FE uses TREE_PURPOSE to store initial values. */
@@ -5886,8 +5903,7 @@ find_decls_types_r (tree *tp, int *ws, v
ctx = BLOCK_SUPERCONTEXT (ctx);
fld_worklist_push (ctx, fld);
}
- /* Do not walk TYPE_CANONICAL. We do not stream it and thus do not
- and want not to reach unused types this way. */
+ fld_worklist_push (TYPE_CANONICAL (t), fld);
if (RECORD_OR_UNION_TYPE_P (t) && TYPE_BINFO (t))
{
--- gcc/testsuite/g++.dg/other/pr89692.C.jj 2019-03-20 20:20:10.233278697
+0100
+++ gcc/testsuite/g++.dg/other/pr89692.C 2019-03-20 20:19:53.193551778
+0100
@@ -0,0 +1,20 @@
+// PR lto/89692
+// { dg-do compile }
+// { dg-require-effective-target lto }
+// { dg-options "-flto -O2" }
+
+struct S {
+ short int a, b;
+ unsigned char c : 1;
+};
+
+bool
+foo (void)
+{
+ unsigned char d[sizeof (S)] = { 0 };
+ S e;
+
+ __builtin_memcpy (&e, d, sizeof (d));
+
+ return e.c == d[0];
+}
Jakub
