On February 21, 2018 11:37:20 PM GMT+01:00, Jakub Jelinek <ja...@redhat.com>
wrote:
>Hi!
>
>The following testcase shows that we set TYPE_EMPTY_P just one of the
>possibly many variants of an aggregate type.
>On the testcase, in one case (in the callee) we check TYPE_EMPTY_P on X
>which is
>the type variant for the using type, and in another case we check it on
>the
>A<int> type instead, which has TYPE_EMPTY_P set.
>
>Bootstrap/regtest pending on x86_64-linux and i686-linux, ok if it
>passes?
OK.
Richard.
>2018-02-21 Jakub Jelinek <ja...@redhat.com>
>
> PR target/84502
> * stor-layout.c (finalize_type_size): Propagate TYPE_EMPTY_P flag
> to all type variants.
>
> * g++.dg/torture/pr84502.C: New test.
>
>--- gcc/stor-layout.c.jj 2018-02-13 21:23:29.187981310 +0100
>+++ gcc/stor-layout.c 2018-02-21 21:43:24.783522853 +0100
>@@ -1883,6 +1883,9 @@ finalize_type_size (tree type)
> && TREE_CODE (TYPE_SIZE_UNIT (type)) != INTEGER_CST)
> TYPE_SIZE_UNIT (type) = variable_size (TYPE_SIZE_UNIT (type));
>
>+ /* Handle empty records as per the x86-64 psABI. */
>+ TYPE_EMPTY_P (type) = targetm.calls.empty_record_p (type);
>+
> /* Also layout any other variants of the type. */
> if (TYPE_NEXT_VARIANT (type)
> || type != TYPE_MAIN_VARIANT (type))
>@@ -1895,6 +1898,7 @@ finalize_type_size (tree type)
> unsigned int precision = TYPE_PRECISION (type);
> unsigned int user_align = TYPE_USER_ALIGN (type);
> machine_mode mode = TYPE_MODE (type);
>+ bool empty_p = TYPE_EMPTY_P (type);
>
> /* Copy it into all variants. */
> for (variant = TYPE_MAIN_VARIANT (type);
>@@ -1911,11 +1915,9 @@ finalize_type_size (tree type)
> SET_TYPE_ALIGN (variant, valign);
> TYPE_PRECISION (variant) = precision;
> SET_TYPE_MODE (variant, mode);
>+ TYPE_EMPTY_P (variant) = empty_p;
> }
> }
>-
>- /* Handle empty records as per the x86-64 psABI. */
>- TYPE_EMPTY_P (type) = targetm.calls.empty_record_p (type);
> }
>
>/* Return a new underlying object for a bitfield started with FIELD.
>*/
>--- gcc/testsuite/g++.dg/torture/pr84502.C.jj 2018-02-21
>22:13:22.279420017 +0100
>+++ gcc/testsuite/g++.dg/torture/pr84502.C 2018-02-21
>22:13:03.727424362 +0100
>@@ -0,0 +1,20 @@
>+// PR target/84502
>+// { dg-do run }
>+
>+template<typename T>
>+struct A { };
>+using X = A<int>;
>+
>+void
>+foo (X, int a1, int a2, int a3, int a4, int a5, int a6, int a7, int
>a8)
>+{
>+ if (a1 != 0 || a2 != 1 || a3 != 2 || a4 != 3
>+ || a5 != 4 || a6 != 5 || a7 != 6 || a8 != 7)
>+ __builtin_abort ();
>+}
>+
>+int
>+main ()
>+{
>+ foo (X{}, 0, 1, 2, 3, 4, 5, 6, 7);
>+}
>
> Jakub
