[gcc/devel/ranger] libstdc++: Make net::service_already_exists default constructible

[Aldy Hernandez <aldyh@gcc.gnu.org>]

https://gcc.gnu.org/g:00082ff88cf4e25fc1041e9effd1c92fbaaa8d62

commit 00082ff88cf4e25fc1041e9effd1c92fbaaa8d62
Author: Jonathan Wakely <jwakely@redhat.com>
Date:   Fri Apr 24 14:15:51 2020 +0100

    libstdc++: Make net::service_already_exists default constructible
    
    The LWG issue I created is Tentatively Ready and proposes to declare a
    public default constructor, rather than the private one I added
    recently.
    
            * include/experimental/executor (service_already_exists): Make default
            constructor public (LWG 3414).
            * testsuite/experimental/net/execution_context/make_service.cc: Check
            the service_already_exists can be default constructed.

Diff:
---
 libstdc++-v3/ChangeLog                                             | 7 +++++++
 libstdc++-v3/include/experimental/executor                         | 7 +++----
 .../testsuite/experimental/net/execution_context/make_service.cc   | 3 +++
 3 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index 7b92ba7eebf..b3d001c02ab 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,3 +1,10 @@
+2020-04-24  Jonathan Wakely  <jwakely@redhat.com>
+
+	* include/experimental/executor (service_already_exists): Make default
+	constructor public (LWG 3414).
+	* testsuite/experimental/net/execution_context/make_service.cc: Check
+	the service_already_exists can be default constructed.
+
 2020-04-24  Kamlesh Kumar  <kamleshbhalui@gmail.com>
 	    Jonathan Wakely  <jwakely@redhat.com>
 
diff --git a/libstdc++-v3/include/experimental/executor b/libstdc++-v3/include/experimental/executor
index fa39eaa0468..3560e345e8a 100644
--- a/libstdc++-v3/include/experimental/executor
+++ b/libstdc++-v3/include/experimental/executor
@@ -129,10 +129,9 @@ inline namespace v1
 
   class service_already_exists : public logic_error
   {
-    template<typename _Service, typename... _Args>
-      friend _Service&
-      make_service(execution_context&, _Args&&...);
-
+  public:
+    // _GLIBCXX_RESOLVE_LIB_DEFECTS
+    // 3414. service_already_exists has no usable constructors
     service_already_exists() : logic_error("service already exists") { }
   };
 
diff --git a/libstdc++-v3/testsuite/experimental/net/execution_context/make_service.cc b/libstdc++-v3/testsuite/experimental/net/execution_context/make_service.cc
index f134add48b5..0898d12927a 100644
--- a/libstdc++-v3/testsuite/experimental/net/execution_context/make_service.cc
+++ b/libstdc++-v3/testsuite/experimental/net/execution_context/make_service.cc
@@ -34,3 +34,6 @@ void test01(net::execution_context& c)
 {
   net::make_service<S>(c);
 }
+
+static_assert(std::is_default_constructible<net::service_already_exists>(),
+	      "LWG 3414. service_already_exists has no usable constructors");