- Copy stable/10 (r259064) to releng/10.0 as part of the
10.0-RELEASE cycle.
- Update __FreeBSD_version [1]
- Set branch name to -RC1

[1] 10.0-CURRENT __FreeBSD_version value ended at '55', so
start releng/10.0 at '100' so the branch is started with
a value ending in zero.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

boot: use -march=i386 for both i386 and amd64 builds

.. so that consistent compilation algorithms are used for both
architectures as in practice the binaries are expected to be
interchangeable (for time being).
Previously i386 used default setting which were equivalent to
-march=i486 -mtune=generic.
The only difference is using smaller but slower "leave" instructions.

Discussed with: jhb, dim
MFC after: 29 days

When building some of the boot loaders with clang, and DEBUG_FLAGS or
CFLAGS having '-g' in it, clang outputs several assembly directives that
are too new for our version of binutils.

Therefore, assemble the resulting .s files with clang instead. A more
general solution can be implemented when a GNU as-compatible driver for
clang's integrated assembler appears.

Reported by: dougb

On i386 and amd64, consistently use the following options whenever we
want to avoid using any "advanced" CPU features:

-mno-mmx -mno-3dnow -mno-sse -mno-sse2 -mno-sse3 -msoft-float

MF tbemd: Minor tweaks, prefer MACHINE_CPUARCH generally to MACHINE_ARCH

Enable GCC stack protection (aka Propolice) for userland:
- It is opt-out for now so as to give it maximum testing, but it may be
turned opt-in for stable branches depending on the consensus. You
can turn it off with WITHOUT_SSP.
- WITHOUT_SSP was previously used to disable the build of GNU libssp.
It is harmless to steal the knob as SSP symbols have been provided
by libc for a long time, GNU libssp should not have been much used.
- SSP is disabled in a few corners such as system bootstrap programs
(sys/boot), process bootstrap code (rtld, csu) and SSP symbols themselves.
- It should be safe to use -fstack-protector-all to build world, however
libc will be automatically downgraded to -fstack-protector because it
breaks rtld otherwise.
- This option is unavailable on ia64.

Enable GCC stack protection (aka Propolice) for kernel:
- It is opt-out for now so as to give it maximum testing.
- Do not compile your kernel with -fstack-protector-all, it won't work.

Submitted by: Jeremie Le Hen <jeremie@le-hen.org>

Add -march=i386 to fix amd64 build by generating the same code
as i386 would do.

Add -mno-sse3 for prescott/nocona

Ensure GCC does not use FP registers in integer code.
I think all we really need is -fno-sse2.
I really don't like cluttering up the compiler invocation,
but this bigger hammer will fix reported problems for now.

- Factor out -nostdlib to an upper level Makefile.inc.

- Now that bsd.prog.mk deals with programs linked with -nostdlib
better, and has a notion of an "internal" program, use PROG
where possible. This has a good impact on the contents of
.depend files and causes programs to be linked with cc(1).

XXX: boot2 couldn't be converted as it's actually two programs.

Tested on: i386, amd64

Untangle building of AMD64 boot code.

Tested on: amd64 (sledge)

First round of cleanups to sys/boot/ makefiles:

- do not use PROG for what's not a real C program,
- use sys.mk transformation rules where possible,
- only create the "machine" symlink on AMD64,
- removed MAINTAINER lines in individual makefiles,
- added the LIBSTAND defitinion to <bsd.libnames.mk>,
- somewhat better contents in .depend files.

Tested on: i386, amd64
Prodded by: bde

Inherit BINDIR from a parent Makefile.inc.

Only include ../Makefile.inc once in loader/Makefile.

Build on amd64. Yes, I know this isn't particularly nice.

-ffreestanding is the word for /sys.

Add -mpreferred-stack-boundary=2 to CFLAGS for i386. This and libstand
reduces /boot/loader from 163840 bytes to 155648 and pxeboot from 165888
bytes to 157696 bytes.

Mega i386 loader commit.
- Don't hard code 0x10000 as the entry point for the loader. Instead add
src/sys/boot/i386/Makefile.inc which defines a make variable with the
entry point for the loader. Move the loader's entry point up to
0x20000, which makes PXE happy.
- Don't try to use cpp to parse btxldr for the optional BTXLDR_VERBOSE,
instead use m4 to achieve this. Also, add a BTXLDR_VERBOSE knob in the
btxldr Makefile to turn this option on.
- Redo parts of cdldr's Makefile so that it now builds and installs cdboot
instead of having i386/loader/Makefile do that. Also, add in some more
variables to make the pxeldr Makefile almost identical and thus to ease
maintainability.
- Teach cdldr about the a.out format. Cdldr now parsers the a.out header
of the loader binary and relocates it based on that. The entry point of
the loader no longer has to be hardcoded into cdldr. Also, the boot
info table from mkisofs is no longer required to get a useful cdboot.
- Update the lsdev function for BIOS disks to parse other file systems
(such as DOS FAT) that we currently support. This is still buggy as
it assumes that a floppy with a DOS boot sector actually has a MBR and
parses it as such. I'll be fixing this in the future.
- The biggie: Add in support for booting off of PXE-enabled network
adapters. Currently, we use the TFTP API provided by the PXE BIOS.
Eventually we will switch to using the low-level NIC driver thus
allowing both TFTP and NFS to be used, but for now it's just TFTP.

Submitted by: ps, alfred
Testing by: Benno Rice <benno@netizen.com.au>