diff --git a/share/man/man5/src.conf.5 b/share/man/man5/src.conf.5
index 9377e20668d1..5c40992f395f 100644
--- a/share/man/man5/src.conf.5
+++ b/share/man/man5/src.conf.5
@@ -1,7 +1,7 @@
 .\" DO NOT EDIT-- this file is automatically generated.
-.\" from FreeBSD: head/tools/build/options/makeman 284708 2015-06-22 20:21:57Z sjg
+.\" from FreeBSD: head/tools/build/options/makeman 287935 2015-09-17 20:45:51Z bdrewery
 .\" $FreeBSD$
-.Dd September 16, 2015
+.Dd September 17, 2015
 .Dt SRC.CONF 5
 .Os
 .Sh NAME
@@ -65,6 +65,18 @@ option of
 or in its environment; see
 .Xr environ 7 .
 .Pp
+The environment of
+.Xr make 1
+for the build can be controlled via the
+.Va SRC_ENV_CONF
+variable, which defaults to
+.Pa /etc/src-env.conf .
+Some examples that may only be set in this file are
+.Va MAKEOBJDIRPREFIX ,
+and
+.Va WITH_META_MODE
+as they are environment-only variables.
+.Pp
 The values of variables are ignored regardless of their setting;
 even if they would be set to
 .Dq Li FALSE
@@ -129,6 +141,11 @@ related programs, libraries, and kernel modules.
 .It Va WITH_AUTO_OBJ
 .\" from FreeBSD: head/tools/build/options/WITH_AUTO_OBJ 284708 2015-06-22 20:21:57Z sjg
 Enable automatic creation of objdirs.
+.Pp
+This must be set in the environment or
+.Pa /etc/src-env.conf ,
+not
+.Pa /etc/src.conf .
 .It Va WITHOUT_BHYVE
 .\" from FreeBSD: head/tools/build/options/WITHOUT_BHYVE 277727 2015-01-26 06:44:48Z ngie
 Set to not build or install
@@ -408,6 +425,11 @@ Cache result of dirdeps.mk which can save significant time
 for subsequent builds.
 Depends on
 .Va WITH_META_MODE .
+.Pp
+This must be set in the environment or
+.Pa /etc/src-env.conf ,
+not
+.Pa /etc/src.conf .
 .It Va WITHOUT_DMAGENT
 .\" from FreeBSD: head/tools/build/options/WITHOUT_DMAGENT 262335 2014-02-22 13:05:23Z bapt
 Set to not build dma Mail Transport Agent
@@ -881,8 +903,13 @@ and related support files.
 .\" from FreeBSD: head/tools/build/options/WITH_META_FILES 284708 2015-06-22 20:21:57Z sjg
 Create meta files during non META_MODE build.
 The meta files can be useful for debugging.
+.Pp
+This must be set in the environment or
+.Pa /etc/src-env.conf ,
+not
+.Pa /etc/src.conf .
 .It Va WITH_META_MODE
-.\" from FreeBSD: head/tools/build/options/WITH_META_MODE 287904 2015-09-17 05:01:04Z bdrewery
+.\" from FreeBSD: head/tools/build/options/WITH_META_MODE 287932 2015-09-17 20:33:52Z bdrewery
 Enable building in meta mode.
 .Pp
 The build is driven by dirdeps.mk using
@@ -938,6 +965,11 @@ is set explicitly)
 .Va WITHOUT_STAGING_PROG
 is set explicitly)
 .El
+.Pp
+This must be set in the environment or
+.Pa /etc/src-env.conf ,
+not
+.Pa /etc/src.conf .
 .It Va WITH_NAND
 .\" from FreeBSD: head/tools/build/options/WITH_NAND 235537 2012-05-17 10:11:18Z gber
 Set to build the NAND Flash components.
@@ -1200,6 +1232,11 @@ is set explicitly)
 .Va WITHOUT_STAGING_PROG
 is set explicitly)
 .El
+.Pp
+This must be set in the environment or
+.Pa /etc/src-env.conf ,
+not
+.Pa /etc/src.conf .
 .It Va WITH_STAGING_MAN
 .\" from FreeBSD: head/tools/build/options/WITH_STAGING_MAN 284708 2015-06-22 20:21:57Z sjg
 Enable staging of MAN pages to stage tree.
@@ -1233,6 +1270,11 @@ support files such as keyboard maps, fonts, and screen output maps.
 Enable use of sysroot during build.
 Depends on
 .Va WITH_META_MODE .
+.Pp
+This must be set in the environment or
+.Pa /etc/src-env.conf ,
+not
+.Pa /etc/src.conf .
 .It Va WITHOUT_TALK
 .\" from FreeBSD: head/tools/build/options/WITHOUT_TALK 277676 2015-01-25 04:37:44Z ngie
 Set to not build or install
@@ -1390,6 +1432,7 @@ Set to not build the timezone database.
 .Sh FILES
 .Bl -tag -compact -width Pa
 .It Pa /etc/src.conf
+.It Pa /etc/src-env.conf
 .It Pa /usr/share/mk/bsd.own.mk
 .El
 .Sh SEE ALSO