Hi!
When a field has reference type, we correctly used the reference type as the
type of the var with value expr, but the DECL_VALUE_EXPR had the type/value
after
convert_from_reference, which leads to invalid IL.
Fixed thusly, bootstrapped/regtested on x86_64-linux and i686-linux, ok for
trunk?
2016-12-29 Jakub Jelinek <ja...@redhat.com>
PR c++/78931
* decl.c (cp_finish_decomp): SET_DECL_VALUE_EXPR to probe rather than
tt.
* g++.dg/cpp1z/decomp19.C: New test.
--- gcc/cp/decl.c.jj 2016-12-21 22:57:08.000000000 +0100
+++ gcc/cp/decl.c 2016-12-28 13:16:45.294616666 +0100
@@ -7598,7 +7598,7 @@ cp_finish_decomp (tree decl, tree first,
probe = TREE_OPERAND (probe, 0);
TREE_TYPE (v[i]) = TREE_TYPE (probe);
layout_decl (v[i], 0);
- SET_DECL_VALUE_EXPR (v[i], tt);
+ SET_DECL_VALUE_EXPR (v[i], probe);
DECL_HAS_VALUE_EXPR_P (v[i]) = 1;
i++;
}
--- gcc/testsuite/g++.dg/cpp1z/decomp19.C.jj 2016-12-28 13:18:27.093305954
+0100
+++ gcc/testsuite/g++.dg/cpp1z/decomp19.C 2016-12-28 13:18:19.000000000
+0100
@@ -0,0 +1,13 @@
+// PR c++/78931
+// { dg-do run { target c++11 } }
+// { dg-options "" }
+
+int
+main ()
+{
+ int x = 99;
+ struct S { int &x; };
+ S s{x};
+ auto [p] = s; // { dg-warning "decomposition declaration only
available with" "" { target c++14_down } }
+ return p - 99;
+}
Jakub
