Makefile: re-wordsmith the blurb about xtoolchain ports

The new version only includes a specific version once, and uses the one
that's currently advised by tinderbox: -gcc6.

It also advises just installing the pkg, but mentions in a side-note at the
end where to find the source in the ports tree.

Reviewed by:	jrtc27
Suggested by:	jhb (use default from tinderbox)
Differential Revision:	https://reviews.freebsd.org/D26820

1 files changed, 10 insertions, 8 deletions

diff --git a/Makefile b/Makefile
index 32d5977c3eacf..90549cadba08d 100644
--- a/Makefile
+++ b/Makefile
@@ -89,14 +89,16 @@
 # 10.  `reboot'
 # 11.  `make delete-old-libs' (in case no 3rd party program uses them anymore)
 #
-# For individuals wanting to build from source with GCC from ports, first build
-# or install an appropriate flavor of devel/freebsd-gcc9.  The packages produced
-# by this port are named "${TARGET_ARCH}-gcc9" -- note that not all
-# architectures supported by FreeBSD have an external gcc toolchain available.
-#
-# Once the appropriate freebsd-gcc package is installed, simply pass
-# CROSS_TOOLCHAIN=${TARGET_ARCH}-gcc9 while building with the above steps,
-# e.g., `make buildworld CROSS_TOOLCHAIN=amd64-gcc9`.
+# For individuals wanting to build from source with GCC from ports, first
+# install the appropriate GCC cross toolchain package:
+#   `pkg install ${TARGET_ARCH}-gccN`
+#
+# Once you have installed the necessary cross toolchain, simply pass
+# CROSS_TOOLCHAIN=${TARGET_ARCH}-gccN while building with the above steps,
+# e.g., `make buildworld CROSS_TOOLCHAIN=amd64-gcc6`.
+#
+# The ${TARGET_ARCH}-gccN packages are provided as flavors of the
+# devel/freebsd-gccN ports.
 #
 # See src/UPDATING `COMMON ITEMS' for more complete information.
 #