Catch a rare, racy error on PyPy subprocess.

src/gevent/__init__.py

@@ -27,7 +27,7 @@ version_info = _version_info(1, 5, 0, 'dev', 0)
 #: Use ``pkg_resources.parse_version(__version__)`` or
 #: ``packaging.version.Version(__version__)`` to get a machine-usable
 #: value.
-__version__ = '1.4.1.dev0'
+__version__ = '1.5.0.dev0'
 
 
 __all__ = [

src/gevent/subprocess.py

@@ -1503,10 +1503,20 @@ class Popen(object):
                 errpipe_read = FileObject(errpipe_read, 'rb')
                 data = errpipe_read.read()
             finally:
+                try:
                     if hasattr(errpipe_read, 'close'):
                         errpipe_read.close()
                     else:
                         os.close(errpipe_read)
+                except OSError:
+                    # Especially on PyPy, we sometimes see the above
+                    # `os.close(errpipe_read)` raise an OSError.
+                    # It's not entirely clear why, but it happens in
+                    # InterprocessSignalTests.test_main sometimes, which must mean
+                    # we have some sort of race condition.
+                    pass
+                finally:
+                    errpipe_read = -1
 
             if data != b"":
                 self.wait()