[PATCH] Avoid deprecation warning with -Wsystem-headers

[Jonathan Wakely]

C++17 says to use std::uncaught_exceptions() here instead of
std::uncaught_exception() but since we only care whether the result is
non-zero (and we aren't planning to remove the deprecated version) we
can just keep using std::uncaught_exception() and suppress the warning.

        * include/std/ostream (basic_ostream::sentry::~sentry): Suppress
        deprecation warnings for using uncaught_exception().

Tested x86_64-linux, committed to trunk.



commit a6d329728aaf20d795ea3e406b2523e9d1a02afd
Author: Jonathan Wakely <jwak...@redhat.com>
Date:   Thu Aug 16 17:36:44 2018 +0100

    Avoid deprecation warning with -Wsystem-headers
    
    C++17 says to use std::uncaught_exceptions() here instead of
    std::uncaught_exception() but since we only care whether the result is
    non-zero (and we aren't planning to remove the deprecated version) we
    can just keep using std::uncaught_exception() and suppress the warning.
    
            * include/std/ostream (basic_ostream::sentry::~sentry): Suppress
            deprecation warnings for using uncaught_exception().

diff --git a/libstdc++-v3/include/std/ostream b/libstdc++-v3/include/std/ostream
index 448a9288188..2099294fd92 100644
--- a/libstdc++-v3/include/std/ostream
+++ b/libstdc++-v3/include/std/ostream
@@ -444,6 +444,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       explicit
       sentry(basic_ostream<_CharT, _Traits>& __os);
 
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
       /**
        *  @brief  Possibly flushes the stream.
        *
@@ -461,6 +463,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
              _M_os.setstate(ios_base::badbit);
          }
       }
+#pragma GCC diagnostic pop
 
       /**
        *  @brief  Quick status checking.