diff --git a/Makefile b/Makefile
index ad77a1dc81..5e944d8a16 100644
--- a/Makefile
+++ b/Makefile
@@ -578,9 +578,11 @@ EXTLIBS =
 
 ifeq ($(uname_S),Linux)
 	NO_STRLCPY = YesPlease
+	THREADED_DELTA_SEARCH = YesPlease
 endif
 ifeq ($(uname_S),GNU/kFreeBSD)
 	NO_STRLCPY = YesPlease
+	THREADED_DELTA_SEARCH = YesPlease
 endif
 ifeq ($(uname_S),UnixWare)
 	CC = cc
@@ -678,6 +680,7 @@ ifeq ($(uname_S),FreeBSD)
 	BASIC_CFLAGS += -I/usr/local/include
 	BASIC_LDFLAGS += -L/usr/local/lib
 	DIR_HAS_BSD_GROUP_SEMANTICS = YesPlease
+	THREADED_DELTA_SEARCH = YesPlease
 endif
 ifeq ($(uname_S),OpenBSD)
 	NO_STRCASESTR = YesPlease
@@ -685,6 +688,7 @@ ifeq ($(uname_S),OpenBSD)
 	NEEDS_LIBICONV = YesPlease
 	BASIC_CFLAGS += -I/usr/local/include
 	BASIC_LDFLAGS += -L/usr/local/lib
+	THREADED_DELTA_SEARCH = YesPlease
 endif
 ifeq ($(uname_S),NetBSD)
 	ifeq ($(shell expr "$(uname_R)" : '[01]\.'),2)
@@ -693,6 +697,7 @@ ifeq ($(uname_S),NetBSD)
 	BASIC_CFLAGS += -I/usr/pkg/include
 	BASIC_LDFLAGS += -L/usr/pkg/lib
 	ALL_LDFLAGS += -Wl,-rpath,/usr/pkg/lib
+	THREADED_DELTA_SEARCH = YesPlease
 endif
 ifeq ($(uname_S),AIX)
 	NO_STRCASESTR=YesPlease