[gcc r15-5868] libstdc++: Disable deprecated warnings for std::rel_ops in std.cc

[Jonathan Wakely]

https://gcc.gnu.org/g:27e5d860879c8f6075231e2a547fe8ead5f382e4

commit r15-5868-g27e5d860879c8f6075231e2a547fe8ead5f382e4
Author: Jonathan Wakely <jwakely@redhat.com>
Date:   Mon Dec 2 16:14:01 2024 +0000

    libstdc++: Disable deprecated warnings for std::rel_ops in std.cc
    
    This avoids some warnings when building the std module.
    
    libstdc++-v3/ChangeLog:
    
            * src/c++23/std.cc.in: Disable deprecated warnings when
            exporting std::rel_ops members.

Diff:
---
 libstdc++-v3/src/c++23/std.cc.in | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/libstdc++-v3/src/c++23/std.cc.in b/libstdc++-v3/src/c++23/std.cc.in
index 16e66c3d9210..7a0ff8edad6e 100644
--- a/libstdc++-v3/src/c++23/std.cc.in
+++ b/libstdc++-v3/src/c++23/std.cc.in
@@ -3151,6 +3151,8 @@ export namespace std
   using std::piecewise_construct_t;
   using std::tuple_element;
   using std::tuple_size;
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
   namespace rel_ops
   {
     using std::rel_ops::operator!=;
@@ -3158,6 +3160,7 @@ export namespace std
     using std::rel_ops::operator<=;
     using std::rel_ops::operator>=;
   }
+#pragma GCC diagnostic pop
 #if __cpp_lib_unreachable
   using std::unreachable;
 #endif