From 9574371d24650a9b2b2112b130df2dd83d2a7447 Mon Sep 17 00:00:00 2001 From: Michael Graczyk Date: Wed, 13 May 2020 17:41:57 -0500 Subject: [PATCH] issue-25872: Fix KeyError using linecache from multiple threads (GH-18007) The crash that this fixes occurs when using traceback and other modules from multiple threads; del cache[filename] can raise a KeyError. (cherry picked from commit d72ea605218bbee6ae46648997d9bb76d0fba460) Co-authored-by: Michael Graczyk --- Lib/linecache.py | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/Lib/linecache.py b/Lib/linecache.py index 3afcce1f0a1456..c87e1807bfafaa 100644 --- a/Lib/linecache.py +++ b/Lib/linecache.py @@ -73,10 +73,10 @@ def checkcache(filename=None): try: stat = os.stat(fullname) except OSError: - del cache[filename] + cache.pop(filename, None) continue if size != stat.st_size or mtime != stat.st_mtime: - del cache[filename] + cache.pop(filename, None) def updatecache(filename, module_globals=None): @@ -86,7 +86,7 @@ def updatecache(filename, module_globals=None): if filename in cache: if len(cache[filename]) != 1: - del cache[filename] + cache.pop(filename, None) if not filename or (filename.startswith('<') and filename.endswith('>')): return []