ok?
Index: bsd.port.mk.5
===================================================================
RCS file: /cvs/src/share/man/man5/bsd.port.mk.5,v
retrieving revision 1.481
diff -u -p -r1.481 bsd.port.mk.5
--- bsd.port.mk.5 29 May 2018 11:45:25 -0000 1.481
+++ bsd.port.mk.5 18 Jun 2018 08:05:05 -0000
@@ -3040,6 +3040,14 @@ to disable the use of
entirely; this should not be set under normal circumstances.
Adds dependencies if necessary, and passes LIBTOOL environment variable to
scripts invocations.
+.Pp
+Many ports using GNU autoconf need an m4 file from the GNU libtool package
+but otherwise work with base
+.Xr libtool 1 .
+In those cases do not set
+.Ev USE_LIBTOOL ,
+instead just set
+.Li BUILD_DEPENDS = devel/libtool.
.It Ev USE_MFS
Set to
.Sq Yes
