--- OS/Makefile-OpenBSD.orig	Tue Nov  7 10:22:10 2023
+++ OS/Makefile-OpenBSD	Tue Nov  7 10:23:09 2023
@@ -24,7 +24,6 @@ EXIWHAT_EGREP_ARG='/exim( |$$)'
 EXIWHAT_KILL_SIGNAL=-USR1
 
 HAVE_IPV6=YES
-CFLAGS += -DNO_EXECINFO
 
 # OpenBSD ships with a too-old Berkeley DB.  NDBM is the default if we don't specify one.
 #USE_DB=yes
