fix tests on ppc machines

Author: picnixz

Lib/test/test_ctypes/test_dlerror.py

@@ -1,6 +1,7 @@
 import _ctypes
 import os
 import platform
+import re
 import sys
 import test.support
 import unittest
@@ -133,24 +134,36 @@ def configure_locales(func):
     @classmethod
     def setUpClass(cls):
         cls.libc_filename = find_library("c")
+        if cls.libc_filename is None:
+            raise unittest.SkipTest('cannot find libc')
+
+    def check_filename_in_dlerror(self, error_message):
+        if not sys.platform.startswith('linux'):
+            # On macOS, the filename is not reported by dlerror().
+            return
+
+        if not re.match(r'(i[3-6]86|x86_64)$', platform.machine()):
+            # On some architectures, the libc file is detected
+            # to be 'libc.so.6' but is incorrectly reported by
+            # dlerror() as libc-X.Y.so.
+            self.skipTest('do not search for filename '
+                          'in dlerror() error message')
+
+        self.assertIn(self.libc_filename, error_message)
 
     @configure_locales
     def test_localized_error_from_dll(self):
         dll = CDLL(self.libc_filename)
         with self.assertRaises(AttributeError) as cm:
             dll.this_name_does_not_exist
-        if sys.platform.startswith('linux'):
-            # On macOS, the filename is not reported by dlerror().
-            self.assertIn(self.libc_filename, str(cm.exception))
+        self.check_filename_in_dlerror(str(cm.exception))
 
     @configure_locales
     def test_localized_error_in_dll(self):
         dll = CDLL(self.libc_filename)
         with self.assertRaises(ValueError) as cm:
             c_int.in_dll(dll, 'this_name_does_not_exist')
-        if sys.platform.startswith('linux'):
-            # On macOS, the filename is not reported by dlerror().
-            self.assertIn(self.libc_filename, str(cm.exception))
+        self.check_filename_in_dlerror(str(cm.exception))
 
     @unittest.skipUnless(hasattr(_ctypes, 'dlopen'),
                          'test requires _ctypes.dlopen()')
@@ -174,9 +187,7 @@ def test_localized_error_dlsym(self):
         dll = _ctypes.dlopen(self.libc_filename)
         with self.assertRaises(OSError) as cm:
             _ctypes.dlsym(dll, 'this_name_does_not_exist')
-        if sys.platform.startswith('linux'):
-            # On macOS, the filename is not reported by dlerror().
-            self.assertIn(self.libc_filename, str(cm.exception))
+        self.check_filename_in_dlerror(str(cm.exception))
 
 
 if __name__ == "__main__":