MFC r309412,r316109,r316132:

r309412 (by imp):

dd is currently a bootstrap tool. It really doesn't have any business
being a bootstrap tool. However, for reproducible build output,
FreeBSD added dd status=none because it was otherwise difficult to
suppress the status information, but retain any errors that might
happen. There's no real reason that dd has to be a build tool, other
than we use status=none unconditional. Remove dd from a bootstrap tool
entirely by only using status=none when available. This may also help
efforts to build the system on non-FreeBSD hosts as well.

r316109:

Don't hardcode input files for stage 1/2 bootloaders; use .ALLSRC instead

This is a better pattern to follow when creating the bootloaders and doing
the relevant space checks to make sure that the sizes aren't exceeded (and
thus, copy-pasting is a bit less error prone).

r316132:

Parameterize out 7680 (15 * 512) as BOOT2SIZE, similar to sys/boot/i386/zfsboot/...

This is being done to make it easier to change in the future--this action might be
needed sooner rather than later because of gcc 6.3.0 bailing, stating that there
is negative free space left (deficit) in the boot2 bootloader.

1 files changed, 7 insertions, 0 deletions

diff --git a/sys/boot/Makefile.inc b/sys/boot/Makefile.inc
index 3545446..5d1d51a 100644
--- a/sys/boot/Makefile.inc
+++ b/sys/boot/Makefile.inc
@@ -1,3 +1,10 @@
 # $FreeBSD$
 
 SSP_CFLAGS=
+
+# The boot loader build uses dd status=none, where possible, for reproducible
+# build output (since performance varies from run to run). Trouble is that
+# option was recently (10.3) added to FreeBSD and is non-standard. Only use it
+# when this test succeeds rather than require dd to be a bootstrap tool.
+DD_NOSTATUS!=(dd status=none count=0 2> /dev/null && echo status=none) || true
+DD=dd ${DD_NOSTATUS}