On Tue, Feb 21, 2017 at 12:37:32PM -0800, Jason Merrill wrote:
> On Sat, Feb 18, 2017 at 12:17 AM, Jakub Jelinek <ja...@redhat.com> wrote:
> > On Fri, Feb 17, 2017 at 09:37:09PM -0500, Jason Merrill wrote:
> >> On Fri, Feb 17, 2017 at 1:52 PM, Jakub Jelinek <ja...@redhat.com> wrote:
> >> > - && die->die_tag != DW_TAG_member)
> >> > + && die->die_tag != DW_TAG_member
> >> > + && (die->die_tag != DW_TAG_variable || !class_scope_p
> >> > (die->die_parent)))
> >>
> >> How about we only check class_scope_p (die->die_parent), and don't
> >> consider the TAG at all? DW_TAG_member should only appear at class
> >> scope.
> >
> > That wouldn't work, because that would avoid adding linkage attributes to
> > methods. I could use:
> > && (die->die_tag == DW_TAG_subprogram || !class_scope_p
> > (die->die_parent))
> > (not 100% sure if some other tag than those can make it here)
> > or
> > && ((die->die_tag != DW_TAG_member || die->die_tag != DW_TAG_variable)
> > || !class_scope_p (die->die_parent))
> > or just use
> > && (!VAR_P (decl) || !class_scope_p (die->die_parent))
> > or similar.
> >
> >> > - if (old_die->die_tag == DW_TAG_member)
> >> > + if (old_die->die_tag == DW_TAG_member
> >> > + || (dwarf_version >= 5 && class_scope_p
> >> > (old_die->die_parent)))
> >>
> >> Likewise here.
> >
> > This spot probably can be changed as you wrote, it is in gen_variable_die,
> > so methods shouldn't appear there.
>
> Hmm, let's think about the behavior we want here. I don't see any
> reason not to put AT_linkage_name on a member DW_TAG_variable; I think
> the old behavior avoided putting it on DW_TAG_member just because it
> isn't defined for DW_TAG_member. So it's not clear to me that we need
> any changes in add_linkage_name or its call site.
Ah, ok. But then we need to make sure gen_variable_die doesn't set
no_linkage_name for -gdwarf-5, because otherwise on the attached testcase
we don't emit linkage_name on b, c, d anywhere (we used to emit that
before).
Starting bootstrap/regtest now, does this look ok if that passes?
2017-02-22 Jakub Jelinek <ja...@redhat.com>
* dwarf2out.c (gen_variable_die): For -gdwarf-5, use DW_TAG_variable
instead of DW_TAG_member for static data member declarations and don't
set no_linkage_name for static inline data members.
(gen_member_die): For -gdwarf-5 don't change DW_TAG_variable
to DW_TAG_member.
* g++.dg/debug/dwarf2/inline-var-2.C: New test.
--- gcc/dwarf2out.c.jj 2017-02-18 17:11:18.759821871 +0100
+++ gcc/dwarf2out.c 2017-02-22 17:48:27.378223877 +0100
@@ -22669,7 +22669,8 @@ gen_variable_die (tree decl, tree origin
&& lang_hooks.decls.decl_dwarf_attribute (decl, DW_AT_inline) != -1)
{
declaration = true;
- no_linkage_name = true;
+ if (dwarf_version < 5)
+ no_linkage_name = true;
}
ultimate_origin = decl_ultimate_origin (decl_or_origin);
@@ -22820,9 +22821,10 @@ gen_variable_die (tree decl, tree origin
}
/* For static data members, the declaration in the class is supposed
- to have DW_TAG_member tag; the specification should still be
- DW_TAG_variable referencing the DW_TAG_member DIE. */
- if (declaration && class_scope_p (context_die))
+ to have DW_TAG_member tag in DWARF{3,4} and we emit it for compatibility
+ also in DWARF2; the specification should still be DW_TAG_variable
+ referencing the DW_TAG_member DIE. */
+ if (declaration && class_scope_p (context_die) && dwarf_version < 5)
var_die = new_die (DW_TAG_member, context_die, decl);
else
var_die = new_die (DW_TAG_variable, context_die, decl);
@@ -24091,7 +24093,8 @@ gen_member_die (tree type, dw_die_ref co
&& get_AT (child, DW_AT_specification) == NULL)
{
reparent_child (child, context_die);
- child->die_tag = DW_TAG_member;
+ if (dwarf_version < 5)
+ child->die_tag = DW_TAG_member;
}
else
splice_child_die (context_die, child);
@@ -24113,7 +24116,7 @@ gen_member_die (tree type, dw_die_ref co
}
/* For C++ inline static data members emit immediately a DW_TAG_variable
- DIE that will refer to that DW_TAG_member through
+ DIE that will refer to that DW_TAG_member/DW_TAG_variable through
DW_AT_specification. */
if (TREE_STATIC (member)
&& (lang_hooks.decls.decl_dwarf_attribute (member, DW_AT_inline)
--- gcc/testsuite/g++.dg/debug/dwarf2/inline-var-2.C.jj 2017-02-22
17:54:28.019597440 +0100
+++ gcc/testsuite/g++.dg/debug/dwarf2/inline-var-2.C 2017-02-22
17:54:10.000000000 +0100
@@ -0,0 +1,35 @@
+// { dg-do compile }
+// { dg-options "-O -std=c++1z -gdwarf-5 -dA -gno-strict-dwarf" }
+// { dg-require-weak "" }
+// { dg-final { scan-assembler-not "DW_TAG_member" { xfail *-*-aix* } } }
+
+inline int a;
+struct S
+{
+ static inline double b = 4.0;
+ static constexpr int c = 2;
+ static constexpr inline char d = 3;
+ static const int j = 7;
+ static int k;
+ static double l;
+} s;
+const int S::j;
+int S::k = 8;
+template <int N>
+inline int e = N;
+int &f = e<2>;
+template <int N>
+struct T
+{
+ static inline double g = 4.0;
+ static constexpr int h = 2;
+ static inline constexpr char i = 3;
+ static const int m = 8;
+ static int n;
+ static double o;
+};
+T<5> t;
+template <>
+const int T<5>::m;
+template <>
+int T<5>::n = 9;
Jakub
