diff --git a/share/mk/sys.mk b/share/mk/sys.mk
index 04294ac60d1..c534cea748c 100644
--- a/share/mk/sys.mk
+++ b/share/mk/sys.mk
@@ -95,7 +95,13 @@ ECHODIR		?=	true
 .endif
 .endif
 
-.if !empty(.MAKEFLAGS:M-n) && ${.MAKEFLAGS:M-n} == "-n"
+.if defined(.PARSEDIR)
+# _+_ appears to be a workaround for the special src .MAKE not working.
+# setting it to + interferes with -N
+_+_		?=
+.elif !empty(.MAKEFLAGS:M-n) && ${.MAKEFLAGS:M-n} == "-n"
+# the check above matches only a single -n, so -n -n will result
+# in _+_ = +
 _+_		?=
 .else
 _+_		?=	+