[PATCH] libstdc++: Fix -fno-exceptions support in testsuite_allocator.h

[Patrick Palka]

OK for trunk?

-- >8 --

This fixes the error

.../testsuite_allocator.h:402:13: error: exception handling disabled, use 
‘-fexceptions’ to enable
  402 |             catch(...)
      |             ^~~~~

seen when running some C++23 library tests with -fno-exceptions.

libstdc++-v3/ChangeLog:

        * testsuite/util/testsuite_allocator.h
        (uneq_allocator::allocate_at_least): Guard try/catch with
        __cpp_exceptions.
---
 libstdc++-v3/testsuite/util/testsuite_allocator.h | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/libstdc++-v3/testsuite/util/testsuite_allocator.h 
b/libstdc++-v3/testsuite/util/testsuite_allocator.h
index 27372a97161d..cb8e9bc01bb9 100644
--- a/libstdc++-v3/testsuite/util/testsuite_allocator.h
+++ b/libstdc++-v3/testsuite/util/testsuite_allocator.h
@@ -394,16 +394,20 @@ namespace __gnu_test
          { return r; }
        else
          {
+#if __cpp_exceptions
            try
+#endif
              {
                get_map().insert(map_type::value_type(
                      reinterpret_cast<void*>(r.ptr), personality));
              }
+#if __cpp_exceptions
            catch(...)
              {
                AllocTraits::deallocate(*this, r.ptr, r.count);
                __throw_exception_again;
              }
+#endif
            return r;
          }
       }
-- 
2.54.0.rc1.54.g60f07c4f5c