From: Fred Drake <fdrake@acm.org>
Date: Tue, 23 Apr 2002 21:19:55 +0000 (+0000)
Subject: Add text about circular references caused by storing frames in local
X-Git-Tag: 2.1~54
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f9b76033ba18ea26aeb6cde139bc192ad9cdbdba;p=thirdparty%2FPython%2Fcpython.git

Add text about circular references caused by storing frames in local
variables.  This closes SF bug #543148.
---

diff --git a/Doc/lib/libinspect.tex b/Doc/lib/libinspect.tex
index 6101ad87e0c2..5b57ba9935e6 100644
--- a/Doc/lib/libinspect.tex
+++ b/Doc/lib/libinspect.tex
@@ -287,3 +287,18 @@ context to return, which are centered around the current line.
   Return a list of frame records for the stack below the current
   exception.
 \end{funcdesc}
+
+Stackframes stored directly or indirectly in local variables can
+easily cause reference cycles the garbage collector can't collect,
+leading to memory leaks.  To avoid this, it's a good idea to
+explicitly remove the cycle in a \keyword{finally} clause.  For
+example:
+
+\begin{verbatim}
+def handle_stackframe_without_leak():
+    frame = inspect.currentframe()
+    try:
+        # do something with the frame
+    finally:
+        del frame
+\end{verbatim}