Issue 12514: Use try/finally to assure that timeit restores GC when done.

Lib/timeit.py

@@ -191,9 +191,11 @@ class Timer:
             it = [None] * number
         gcold = gc.isenabled()
         gc.disable()
-        timing = self.inner(it, self.timer)
-        if gcold:
-            gc.enable()
+        try:
+            timing = self.inner(it, self.timer)
+        finally:
+            if gcold:
+                gc.enable()
         return timing
 
     def repeat(self, repeat=default_repeat, number=default_number):

Misc/ACKS

@@ -722,6 +722,7 @@ Chris Rebert
 Marc Recht
 John Redford
 Terry Reedy
+Gareth Rees
 Steve Reeves
 Lennart Regebro
 Ofir Reichenberg

Misc/NEWS

@@ -39,6 +39,9 @@ Library
 
 - Issue #12603: Fix pydoc.synopsis() on files with non-negative st_mtime.
 
+- Issue #12514: Use try/finally to assure the timeit module restores garbage
+  collections when it is done.
+
 - Issue #12607: In subprocess, fix issue where if stdin, stdout or stderr is
   given as a low fd, it gets overwritten.