Index: mpi4py/test/test_pack.py
===================================================================
--- mpi4py.orig/test/test_pack.py	2025-07-18 14:33:20.944111712 +0200
+++ mpi4py/test/test_pack.py	2025-07-18 14:33:20.932112476 +0200
@@ -6,6 +6,7 @@
 
 from mpi4py import MPI
 
+import platform
 
 def allclose(a, b, rtol=1.0e-5, atol=1.0e-8):
     try:
@@ -113,6 +114,7 @@
                         real_size = pack_size - overhead
                         self.assertGreaterEqual(real_size, 0)
 
+    @unittest.skipMPI("openmpi(<5.0)", platform.machine() == 'sparc64')
     def testPackUnpackExternal(self):
         for array, typecode1 in arrayimpl.loop():
             with arrayimpl.test(self):