[committed] libstdc++: Add missing equality comparison in new tests [PR117921]

[Jonathan Wakely]

These new tests fail in Debug Mode because the allocator types aren't
equality comparable.

libstdc++-v3/ChangeLog:

        PR libstdc++/117921
        * testsuite/23_containers/set/modifiers/swap/adl.cc: Add
        equality comparison for Allocator.
        * testsuite/23_containers/unordered_set/modifiers/swap-2.cc:
        Likewise.
---

Tested x86_64-linux. Pushed to trunk.

 libstdc++-v3/testsuite/23_containers/set/modifiers/swap/adl.cc   | 1 +
 .../testsuite/23_containers/unordered_set/modifiers/swap-2.cc    | 1 +
 2 files changed, 2 insertions(+)

diff --git a/libstdc++-v3/testsuite/23_containers/set/modifiers/swap/adl.cc 
b/libstdc++-v3/testsuite/23_containers/set/modifiers/swap/adl.cc
index 2b7975a366f..e2a1742c953 100644
--- a/libstdc++-v3/testsuite/23_containers/set/modifiers/swap/adl.cc
+++ b/libstdc++-v3/testsuite/23_containers/set/modifiers/swap/adl.cc
@@ -36,6 +36,7 @@ namespace adl
       using propagate_on_container_swap = std::true_type;
 
       friend void swap(Allocator&, Allocator&) { swapped = true; }
+      friend bool operator==(Allocator, Allocator) { return true; }
     };
 }
 
diff --git 
a/libstdc++-v3/testsuite/23_containers/unordered_set/modifiers/swap-2.cc 
b/libstdc++-v3/testsuite/23_containers/unordered_set/modifiers/swap-2.cc
index a0fb1a6f662..9d8b2200e24 100644
--- a/libstdc++-v3/testsuite/23_containers/unordered_set/modifiers/swap-2.cc
+++ b/libstdc++-v3/testsuite/23_containers/unordered_set/modifiers/swap-2.cc
@@ -43,6 +43,7 @@ namespace adl
       using propagate_on_container_swap = std::true_type;
 
       friend void swap(Allocator&, Allocator&) { swapped = true; }
+      friend bool operator==(Allocator, Allocator) { return true; }
     };
 }
 
-- 
2.47.1