From fef7e94fa12f21c09997bd02809e677830966646 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C5=81ukasz=20Langa?= <lukasz@langa.pl>
Date: Fri, 9 Sep 2016 21:47:46 -0700
Subject: [PATCH] Don't run garbage collection on interpreter exit if it was
 explicitly disabled by the user.

---
 Include/objimpl.h    | 3 ++-
 Modules/gcmodule.c   | 9 +++++++++
 Python/pylifecycle.c | 6 +++---
 3 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/Include/objimpl.h b/Include/objimpl.h
index 65b6d91c36c..519ae516053 100644
--- a/Include/objimpl.h
+++ b/Include/objimpl.h
@@ -224,11 +224,12 @@ PyAPI_FUNC(void) PyObject_SetArenaAllocator(PyObjectArenaAllocator *allocator);
  * ==========================
  */
 
-/* C equivalent of gc.collect(). */
+/* C equivalent of gc.collect() which ignores the state of gc.enabled. */
 PyAPI_FUNC(Py_ssize_t) PyGC_Collect(void);
 
 #ifndef Py_LIMITED_API
 PyAPI_FUNC(Py_ssize_t) _PyGC_CollectNoFail(void);
+PyAPI_FUNC(Py_ssize_t) _PyGC_CollectIfEnabled(void);
 #endif
 
 /* Test if a type has a GC head */
diff --git a/Modules/gcmodule.c b/Modules/gcmodule.c
index 2575d96d71c..754348e20a9 100644
--- a/Modules/gcmodule.c
+++ b/Modules/gcmodule.c
@@ -1596,6 +1596,15 @@ PyGC_Collect(void)
     return n;
 }
 
+Py_ssize_t
+_PyGC_CollectIfEnabled(void)
+{
+    if (!enabled)
+        return 0;
+
+    return PyGC_Collect();
+}
+
 Py_ssize_t
 _PyGC_CollectNoFail(void)
 {
diff --git a/Python/pylifecycle.c b/Python/pylifecycle.c
index f93afd234da..5b5cc2b55e8 100644
--- a/Python/pylifecycle.c
+++ b/Python/pylifecycle.c
@@ -600,12 +600,12 @@ Py_FinalizeEx(void)
      * XXX but I'm unclear on exactly how that one happens.  In any case,
      * XXX I haven't seen a real-life report of either of these.
      */
-    PyGC_Collect();
+    _PyGC_CollectIfEnabled();
 #ifdef COUNT_ALLOCS
     /* With COUNT_ALLOCS, it helps to run GC multiple times:
        each collection might release some types from the type
        list, so they become garbage. */
-    while (PyGC_Collect() > 0)
+    while (_PyGC_CollectIfEnabled() > 0)
         /* nothing */;
 #endif
     /* Destroy all modules */
@@ -632,7 +632,7 @@ Py_FinalizeEx(void)
      * XXX Python code getting called.
      */
 #if 0
-    PyGC_Collect();
+    _PyGC_CollectIfEnabled();
 #endif
 
     /* Disable tracemalloc after all Python objects have been destroyed,