On Sat, Apr 04, 2020 at 12:08:38AM -0400, Jason Merrill wrote:
> http://eel.is/c++draft/dcl.spec.auto#3 says it has to appear as a
> decl-specifier.
>
> http://eel.is/c++draft/temp.deduct.type#8 lists the forms where a template
> argument can be deduced.
>
> Looks like you are missing arrays, pointers to members, and function return
> types.
I have added that to dwarf2out.c but have a hard time figuring out how to
write the array case (added just the pointer, pointer-to-member (both data
and function) and pointer to function cases to the testcase so far).
Tried
auto (&m22 ())[2] { return w; }
but that is rejected with:
pr94459.C:40:10: error: ‘m22’ declared as array of ‘auto’
40 | auto (&m22 ())[2] { return w; }
| ^~~
2020-04-04 Hannes Domani <ssb...@yahoo.de>
Jakub Jelinek <ja...@redhat.com>
PR debug/94459
* dwarf2out.c (gen_subprogram_die): Look through references, pointers,
arrays, pointer-to-members, function types and qualifiers when
checking if in-class DIE had an 'auto' or 'decltype(auto)' return type
to emit type again on definition.
* g++.dg/debug/pr94459.C: New test.
--- gcc/dwarf2out.c.jj 2020-04-04 00:35:03.450199722 +0200
+++ gcc/dwarf2out.c 2020-04-04 09:45:27.821396824 +0200
@@ -22905,11 +22905,22 @@ gen_subprogram_die (tree decl, dw_die_re
!= (unsigned) s.column))
add_AT_unsigned (subr_die, DW_AT_decl_column, s.column);
- /* If the prototype had an 'auto' or 'decltype(auto)' return type,
- emit the real type on the definition die. */
+ /* If the prototype had an 'auto' or 'decltype(auto)' in
+ the return type, emit the real type on the definition die. */
if (is_cxx () && debug_info_level > DINFO_LEVEL_TERSE)
{
dw_die_ref die = get_AT_ref (old_die, DW_AT_type);
+ while (die
+ && (die->die_tag == DW_TAG_reference_type
+ || die->die_tag == DW_TAG_rvalue_reference_type
+ || die->die_tag == DW_TAG_pointer_type
+ || die->die_tag == DW_TAG_const_type
+ || die->die_tag == DW_TAG_volatile_type
+ || die->die_tag == DW_TAG_restrict_type
+ || die->die_tag == DW_TAG_array_type
+ || die->die_tag == DW_TAG_ptr_to_member_type
+ || die->die_tag == DW_TAG_subroutine_type))
+ die = get_AT_ref (die, DW_AT_type);
if (die == auto_die || die == decltype_auto_die)
add_type_attribute (subr_die, TREE_TYPE (TREE_TYPE (decl)),
TYPE_UNQUALIFIED, false, context_die);
--- gcc/testsuite/g++.dg/debug/pr94459.C.jj 2020-04-04 09:24:19.655238506
+0200
+++ gcc/testsuite/g++.dg/debug/pr94459.C 2020-04-04 09:44:07.572588212
+0200
@@ -0,0 +1,63 @@
+// PR debug/94459
+// { dg-do compile { target c++14 } }
+// { dg-options "-g -dA" }
+
+auto
+baz ()
+{
+ return 0L;
+}
+
+template <typename T>
+struct S
+{
+ T v;
+ T w[2];
+ S () : v (0), w { 0, 0 } {}
+ auto m1 () { return v; }
+ auto &m2 () { return v; }
+ auto &&m3 () { return (T&&)v; }
+ const auto m4 () { return v; }
+ const auto &m5 () { return v; }
+ const auto &&m6 () { return (T&&)v; }
+ volatile auto m7 () { return v; }
+ volatile auto &m8 () { return v; }
+ volatile auto &&m9 () { return (T&&)v; }
+ volatile const auto m10 () { return v; }
+ volatile const auto &m11 () { return v; }
+ volatile const auto &&m12 () { return (T&&)v; }
+ const volatile auto m13 () { return v; }
+ const volatile auto &m14 () { return v; }
+ const volatile auto &&m15 () { return (T&&)v; }
+#ifndef __STRICT_ANSI__
+ __restrict const volatile auto &&m16 () { return (T&&)v; }
+ const __restrict auto &m17 () { return v; }
+#endif
+ auto *m18 () { return &v; }
+ auto (S::* (m19 ())) () { return &S::m1; }
+ auto (S::* (m20 ())) { return &S::v; }
+ auto (*m21 ()) () { return baz; }
+};
+
+S<long> s, u, v;
+
+long
+foo ()
+{
+ auto x = s.m19 ();
+ auto y = s.m20 ();
+ auto z = s.m21 ();
+ return s.m1 () + s.m2 () + s.m3 () + s.m4 () + s.m5 ()
+ + s.m6 () + s.m7 () + s.m8 () + s.m9 () + s.m10 ()
+ + s.m11 () + s.m12 () + s.m13 () + s.m14 () + s.m15 ()
+#ifndef __STRICT_ANSI__
+ + u.m16 () + v.m17 ()
+#endif
+ + *s.m18 () + (s.*x) () + s.*y + z ();
+}
+
+int
+main ()
+{
+ return foo ();
+}
Jakub
