diff -r d46a38c07b1a -r 8c828beb7543 mercurial/configitems.py
--- a/mercurial/configitems.py	Tue May 22 21:51:20 2018 -0400
+++ b/mercurial/configitems.py	Fri May 18 21:24:06 2018 +0900
@@ -1127,6 +1127,9 @@
 coreconfigitem('ui', 'rollback',
     default=True,
 )
+coreconfigitem('ui', 'signal-safe-lock',
+    default=True,
+)
 coreconfigitem('ui', 'slash',
     default=False,
 )