[gcc r13-7508] libstdc++: Add preprocessor checks to <experimental/internet> [PR100285]

[Jonathan Wakely <redi@gcc.gnu.org>]

https://gcc.gnu.org/g:132015b9c6c9f9156ff31f7d66ba92cf01d0bc90

commit r13-7508-g132015b9c6c9f9156ff31f7d66ba92cf01d0bc90
Author: Jonathan Wakely <jwakely@redhat.com>
Date:   Fri Jun 9 12:15:21 2023 +0100

    libstdc++: Add preprocessor checks to <experimental/internet> [PR100285]
    
    We can't define endpoints and resolvers without the relevant OS support.
    If IPPROTO_TCP and IPPROTO_UDP are both undefined then we won't need
    basic_endpoint and basic_resolver anyway, so make them depend on those
    macros.
    
    libstdc++-v3/ChangeLog:
    
            PR libstdc++/100285
            * include/experimental/internet [IPPROTO_TCP || IPPROTO_UDP]
            (basic_endpoint, basic_resolver_entry, resolver_base)
            (basic_resolver_results, basic_resolver): Only define if the tcp
            or udp protocols will be defined.
    
    (cherry picked from commit 793ed718b522b15e2d758eca953feeec1979fe2c)

Diff:
---
 libstdc++-v3/include/experimental/internet | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/libstdc++-v3/include/experimental/internet b/libstdc++-v3/include/experimental/internet
index 1f63c61ce85..bd9a05f12aa 100644
--- a/libstdc++-v3/include/experimental/internet
+++ b/libstdc++-v3/include/experimental/internet
@@ -1502,6 +1502,7 @@ namespace ip
     operator<<(basic_ostream<_CharT, _Traits>& __os, const network_v6& __net)
     { return __os << __net.to_string(); }
 
+#if defined IPPROTO_TCP || defined  IPPROTO_UDP
   /// An IP endpoint.
   template<typename _InternetProtocol>
     class basic_endpoint
@@ -2187,6 +2188,7 @@ namespace ip
       __ec = std::make_error_code(errc::operation_not_supported);
 #endif
     }
+#endif // IPPROTO_TCP || IPPROTO_UDP
 
   /** The name of the local host.
    * @{