debug/78112: remove recent duplicates for DW_TAG_subprogram attributes

Disable unnecessary calls to dwarf2out_decl for the parents of nested
functions. This fixes a libstdc++ build regression on
x86_64-apple-darwin, as these calls used to add duplicate attributes
(for instance DW_AT_inline and DW_AT_object_pointer) to the
corresponding DW_TAG_subprogram DIE.

Bootstrapped and regtested on x86_64-linux.

gcc/
	PR debug/78112
	* dwarf2out.c (dwarf2out_early_global_decl): Call dwarf2out_decl
	on the context only when it has no DIE yet.

testsuite/
	PR debug/78112
	* g++.dg/pr78112.C: New testcase

Co-Authored-By: Jakub Jelinek <jakub@redhat.com>

From-SVN: r242035

4 files changed, 178 insertions, 4 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 5167ede..f5c9add 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2016-11-10  Pierre-Marie de Rodat  <derodat@adacore.com>
+
+	PR debug/78112
+	* dwarf2out.c (dwarf2out_early_global_decl): Call dwarf2out_decl
+	on the context only when it has no DIE yet.
+
 2016-11-10  Richard Earnshaw  <rearnsha@arm.com>
 
 	* arm.h (target_cpus): Delete.
diff --git a/gcc/dwarf2out.c b/gcc/dwarf2out.c
index 1dfff38..f9ec090 100644
--- a/gcc/dwarf2out.c
+++ b/gcc/dwarf2out.c
@@ -25256,11 +25256,11 @@ dwarf2out_early_global_decl (tree decl)
 	  if (!DECL_STRUCT_FUNCTION (decl))
 	    goto early_decl_exit;
 
-	  /* For nested functions, emit DIEs for the parents first so that all
-	     nested DIEs are generated at the proper scope in the first
-	     shot.  */
+	  /* For nested functions, make sure we have DIEs for the parents first
+	     so that all nested DIEs are generated at the proper scope in the
+	     first shot.  */
 	  tree context = decl_function_context (decl);
-	  if (context != NULL)
+	  if (context != NULL && lookup_decl_die (context) == NULL)
 	    {
 	      current_function_decl = context;
 	      dwarf2out_decl (context);
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 62cc516..9dfd15c 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,9 @@
+2016-11-10  Pierre-Marie de Rodat  <derodat@adacore.com>
+	    Jakub Jelinek  <jakub@redhat.com>
+
+	PR debug/78112
+	* g++.dg/pr78112.C: New testcase
+
 2016-11-09  Jakub Jelinek  <jakub@redhat.com>
 
 	* g++.dg/asan/asan_test.C: Remove -Wno-format, add
diff --git a/gcc/testsuite/g++.dg/pr78112.C b/gcc/testsuite/g++.dg/pr78112.C
new file mode 100644
index 0000000..95d9e59
--- /dev/null
+++ b/gcc/testsuite/g++.dg/pr78112.C
@@ -0,0 +1,162 @@
+/* { dg-do compile } */
+/* { dg-options "-g -dA -std=gnu++11" } */
+/* { dg-final { scan-assembler-times DW_AT_inline 6 } } */
+/* { dg-final { scan-assembler-times DW_AT_object_pointer 37 } } */
+namespace std
+{
+template <typename _Tp> struct integral_constant
+{
+  static constexpr _Tp value = 0;
+};
+template <int> using __bool_constant = integral_constant<int>;
+struct __not_ : integral_constant<int>
+{
+};
+template <typename, typename, template <typename...> class _Op,
+          typename... _Args>
+struct __detector
+{
+  using type = _Op<_Args...>;
+};
+template <typename _Default, template <typename...> class _Op,
+          typename... _Args>
+using __detected_or = __detector<_Default, void, _Op, _Args...>;
+template <typename _Default, template <typename...> class _Op,
+          typename... _Args>
+using __detected_or_t = typename __detected_or<_Default, _Op, _Args...>::type;
+template <template <typename...> class _Default,
+          template <typename...> class _Op, typename... _Args>
+using __detected_or_t_ = __detected_or_t<_Default<_Args...>, _Op, _Args...>;
+template <typename, typename> struct pair;
+template <typename, typename> using __replace_first_arg_t = int;
+}
+class new_allocator
+{
+};
+namespace std
+{
+template <typename> using __allocator_base = new_allocator;
+template <typename> class allocator : __allocator_base<int>
+{
+};
+template <typename> struct equal_to;
+struct __allocator_traits_base
+{
+  template <typename _Alloc, typename _Up>
+  using __rebind = typename _Alloc::template rebind<_Up>::other;
+};
+template <typename _Alloc, typename _Up>
+using __alloc_rebind
+    = __detected_or_t_<__replace_first_arg_t,
+                       __allocator_traits_base::__rebind, _Alloc, _Up>;
+}
+struct __alloc_traits
+{
+  static int _S_select_on_copy;
+};
+namespace std
+{
+template <typename> struct hash;
+namespace __detail
+{
+struct _Select1st;
+struct _Hashtable_traits
+{
+  using __hash_cached = __bool_constant<0>;
+};
+template <typename, int> struct _Hash_node;
+template <typename _Value> struct _Hash_node<_Value, 0>
+{
+  int &_M_v ();
+};
+struct _Mod_range_hashing;
+struct _Default_ranged_hash;
+struct _Prime_rehash_policy
+{
+  using __has_load_factor = integral_constant<int>;
+};
+struct _Map_base
+{
+};
+struct _Insert
+{
+};
+template <typename _Policy>
+using __has_load_factor = typename _Policy::__has_load_factor;
+template <typename _RehashPolicy, typename,
+          typename = __detected_or_t<integral_constant<bool>,
+                                     __has_load_factor, _RehashPolicy> >
+struct _Rehash_base;
+template <typename _RehashPolicy, typename _Traits>
+struct _Rehash_base<_RehashPolicy, _Traits, integral_constant<int> > {};
+struct _Hashtable_ebo_helper { template <typename _OtherTp> _Hashtable_ebo_helper (_OtherTp); };
+struct _Hashtable_base {};
+struct _Equality {};
+template <typename _NodeAlloc> struct _Hashtable_alloc : _Hashtable_ebo_helper
+{
+  using __ebo_node_alloc = _Hashtable_ebo_helper;
+  using __node_type = typename _NodeAlloc::value_type;
+  using __node_alloc_traits = __alloc_traits;
+  template <typename _Alloc> _Hashtable_alloc (_Alloc) : __ebo_node_alloc (0) {}
+  template <typename... _Args> __node_type *_M_allocate_node (...);
+};
+}
+template <typename, typename> using __cache_default = __not_;
+template <typename _Key, typename _Value, typename _Alloc, typename _ExtractKey, typename _Equal, typename _H1, typename _H2,
+          typename _Hash, typename _RehashPolicy, typename _Traits>
+struct _Hashtable : __detail::_Hashtable_base, __detail::_Map_base, __detail::_Insert, __detail::_Rehash_base<_RehashPolicy, int>,
+  __detail::_Equality, __detail:: _Hashtable_alloc<__alloc_rebind<_Alloc, __detail::_Hash_node<_Value, _Traits::__hash_cached::value> > >
+{
+  using __traits_type = _Traits;
+  using __hash_cached = typename __traits_type::__hash_cached;
+  using __node_type = __detail::_Hash_node<_Value, __hash_cached::value>;
+  using __node_alloc_type = __alloc_rebind<_Alloc, __node_type>;
+  using __hashtable_alloc = __detail::_Hashtable_alloc<__node_alloc_type>;
+  using typename __hashtable_alloc::__node_alloc_traits;
+  _Key key_type;
+  _RehashPolicy _M_rehash_policy;
+  template <typename _NodeGenerator>
+  void _M_assign (const _Hashtable &, const _NodeGenerator &);
+  _Hashtable ();
+  _Hashtable (const _Hashtable &);
+};
+template <typename _Key, typename _Value, typename _Alloc, typename _ExtractKey, typename _Equal, typename _H1, typename _H2,
+          typename _Hash, typename _RehashPolicy, typename _Traits>
+template <typename _NodeGenerator>
+void _Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal, _H1, _H2, _Hash, _RehashPolicy,
+                _Traits>::_M_assign (const _Hashtable &__ht, const _NodeGenerator &__node_gen) try {
+__node_type *__this_n = __node_gen (0); } catch (...) {}
+template <typename _Key, typename _Value, typename _Alloc, typename _ExtractKey, typename _Equal, typename _H1, typename _H2,
+          typename _Hash, typename _RehashPolicy, typename _Traits>
+_Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal, _H1, _H2, _Hash, _RehashPolicy, _Traits>::_Hashtable (const _Hashtable &__ht)
+    : __hashtable_alloc (__node_alloc_traits::_S_select_on_copy), _M_rehash_policy ()
+{
+  _M_assign (__ht, [this](__node_type *__n) { return this->_M_allocate_node (__n->_M_v ()); });
+}
+template <bool _Cache> using __umap_traits = __detail::_Hashtable_traits;
+template <typename _Key, typename _Tp, typename _Hash = hash<_Key>, typename _Pred = std::equal_to<_Key>,
+          typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >,
+          typename _Tr = __umap_traits<__cache_default<_Key, _Hash>::value> >
+using __umap_hashtable = _Hashtable<_Key, std::pair<const _Key, _Tp>, _Alloc, __detail::_Select1st, _Pred, _Hash,
+                                    __detail::_Mod_range_hashing, __detail::_Default_ranged_hash, __detail::_Prime_rehash_policy, _Tr>;
+template <class _Key, class _Tp, class _Hash = hash<_Key>, class _Pred = std::equal_to<_Key>,
+          class _Alloc = std::allocator<std::pair<const _Key, _Tp> > >
+struct unordered_map
+{
+  typedef __umap_hashtable<_Key, _Tp, _Hash, _Pred, _Alloc> _Hashtable;
+  _Hashtable _M_h;
+  unordered_map (const int &__a) : _M_h () {}
+};
+}
+struct uneq_allocator_base {};
+template <typename Tp> struct uneq_allocator : uneq_allocator_base { typedef Tp value_type; };
+template <typename Tp, typename Alloc = std::allocator<Tp> >
+struct Trans_NS___gnu_test_propagating_allocator : public uneq_allocator<Tp>
+{
+  template <typename Up> struct rebind { typedef Trans_NS___gnu_test_propagating_allocator<Up, int> other; };
+};
+void fn1 ()
+{
+  std::unordered_map<int, int, int, int, Trans_NS___gnu_test_propagating_allocator<int> > v1 (0);
+  std::unordered_map<int, int, int, int, Trans_NS___gnu_test_propagating_allocator<int> > v2 (v1);
+}