From 9392e7a86f9b133c7097b828dc0b1999fce5ea10 Mon Sep 17 00:00:00 2001
From: Paul Fisher <pfisher@lyft.com>
Date: Fri, 18 Mar 2016 16:50:03 -0700
Subject: [PATCH] clean up sys.exc_info calls to drop circular refs

---
 gunicorn/_compat.py         |  7 ++-----
 gunicorn/workers/base.py    | 13 ++++++++-----
 gunicorn/workers/gthread.py |  3 +--
 gunicorn/workers/sync.py    |  3 +--
 4 files changed, 12 insertions(+), 14 deletions(-)

diff --git a/gunicorn/_compat.py b/gunicorn/_compat.py
index 38fefe44ff..e4e6b215e7 100644
--- a/gunicorn/_compat.py
+++ b/gunicorn/_compat.py
@@ -107,11 +107,8 @@ def _wrap_error(exc, mapping, key):
     new_err = new_err_cls(*exc.args)
 
     # raise a new exception with the original traceback
-    if hasattr(exc, '__traceback__'):
-        traceback = exc.__traceback__
-    else:
-        traceback = sys.exc_info()[2]
-    six.reraise(new_err_cls, new_err, traceback)
+    six.reraise(new_err_cls, new_err,
+                exc.__traceback__ if hasattr(exc, '__traceback__') else sys.exc_info()[2])
 
 if PY33:
     import builtins
diff --git a/gunicorn/workers/base.py b/gunicorn/workers/base.py
index 9ba8e7568b..f33a4f082a 100644
--- a/gunicorn/workers/base.py
+++ b/gunicorn/workers/base.py
@@ -134,11 +134,14 @@ def load_wsgi(self):
 
             self.log.exception(e)
 
-            exc_type, exc_val, exc_tb = sys.exc_info()
-            self.reloader.add_extra_file(exc_val.filename)
-
-            tb_string = traceback.format_exc(exc_tb)
-            self.wsgi = util.make_fail_app(tb_string)
+            try:
+                exc_type, exc_val, exc_tb = sys.exc_info()
+                self.reloader.add_extra_file(exc_val.filename)
+
+                tb_string = traceback.format_exc(exc_tb)
+                self.wsgi = util.make_fail_app(tb_string)
+            finally:
+                del exc_tb
 
     def init_signals(self):
         # reset signaling
diff --git a/gunicorn/workers/gthread.py b/gunicorn/workers/gthread.py
index 25a7e57b52..d66fe4824d 100644
--- a/gunicorn/workers/gthread.py
+++ b/gunicorn/workers/gthread.py
@@ -339,9 +339,8 @@ def handle_request(self, req, conn):
                 self.log.debug("Closing connection.")
                 return False
         except EnvironmentError:
-            exc_info = sys.exc_info()
             # pass to next try-except level
-            six.reraise(exc_info[0], exc_info[1], exc_info[2])
+            six.reraise(*sys.exc_info())
         except Exception:
             if resp and resp.headers_sent:
                 # If the requests have already been sent, we should close the
diff --git a/gunicorn/workers/sync.py b/gunicorn/workers/sync.py
index c59c2e9652..15ac08432f 100644
--- a/gunicorn/workers/sync.py
+++ b/gunicorn/workers/sync.py
@@ -182,9 +182,8 @@ def handle_request(self, listener, req, client, addr):
                 if hasattr(respiter, "close"):
                     respiter.close()
         except EnvironmentError:
-            exc_info = sys.exc_info()
             # pass to next try-except level
-            six.reraise(exc_info[0], exc_info[1], exc_info[2])
+            six.reraise(*sys.exc_info())
         except Exception:
             if resp and resp.headers_sent:
                 # If the requests have already been sent, we should close the