Copy stable/9 to releng/9.3 as part of the 9.3-RELEASE cycle.

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

MFC r245133:
Only assign the environ in the startup code when environ is NULL.

Note that this is not the merge, but a reimplementation of the fix,
done for the not-consolidated code in the stable/9.

MFC r234502:

After r217375, some startup objects under lib/csu are built in a special
way: first they are compiled to assembly, then some sed'ing is done on
the assembly, and lastly the assembly is compiled to an object file.

This last step is done using ${CC}, and not ${AS}, because when the
compiler is clang, it outputs directives that are too advanced for our
old gas. So we use clang's integrated assembler instead. (When the
compiler is gcc, it just calls gas, and nothing is different, except one
extra fork.)

However, in the .s to .o rules in lib/csu/$ARCH/Makefile, I still passed
CFLAGS to the compiler, instead of ACFLAGS, which are specifically for
compiling .s files.

In case you are using '-g' for debug info anywhere in your CFLAGS, it
causes the .s files to already contain debug information in the assembly
itself. In the next step, the .s files are also compiled using '-g',
and if the compiler is clang, it complains: "error: input can't have
.file dwarf directives when -g is used to generate dwarf debug info for
assembly code".

Fix this by using ${ACFLAGS} for compiling the .s files instead.

Reported by: jasone

Copy head to stable/9 as part of 9.0-RELEASE release cycle.

Approved by: re (implicit)

Build Scrt.o on powerpc64. Its introduction on other platforms got lost
during the period of time the powerpc64 port was on a project branch.

Turn off default generation of userland dot symbols on powerpc64 now that
we have a binutils that supports it. Kernel dot symbols remain on to assist
DDB.

Mark csu on PowerPC as not requiring executable stack.

Reviewed and tested by: nwhitehorn

Apply a workaround for a binutils issue with the .note.ABI-tag section
generated from lib/csu/common/crtbrand.c (which ultimately ends up in
executables and shared libraries, via crt1.o, gcrt1.o or Scrt1.o).

For all arches except sparc, gcc emits the section directive for the
abitag struct in crtbrand.c with a PROGBITS type. However, newer
versions of binutils (after 2.16.90) require the section to be of NOTE
type, to guarantee that the .note.ABI-tag section correctly ends up in
the first page of the final executable.

Unfortunately, there is no clean way to tell gcc to use another section
type, so crtbrand.c (or the C files that include it) must be compiled in
multiple steps:

- Compile the .c file to a .s file.
- Edit the .s file to change the 'progbits' type to 'note', for the section
directive that defines the .note.ABI-tag section.
- Compile the .s file to an object file.

These steps are done in the invididual Makefiles for each applicable arch.

Reviewed by: kib

Let all .c and .S files under lib/csu consistently use the __FBSDID()
macro for identification, instead of several different hand-rolled
variants (plain .ident, .ascii, etc).

C startup support for 64-bit PowerPC.

Obtained from: projects/ppc64

Use default WARNS setting (of 6) for lib/csu.

PR: bin/140089
Reviewed by: jmallett
Approved by: ed (co-mentor)

Properly declare non-extern functions in crt1

Also move the declarations after __progname consistently to
make the distinction clearer.

Reviewed by: jmallett
Approved by: ed (co-mentor)

Properly support -fPIE by linking PIE binaries with specially-built
Scrt1.o instead of crt1.o, since the later is built as non-PIC.

Separate i386-elf crt1.c into the pure assembler part and C code,
supplying all data extracted by assembler stub as explicit parameters [1].
Hide and localize _start1 symbol used as an interface between asm and
C code.

In collaboration with: kan
Inspired by: PR i386/127387 [1]
Prodded and tested by: rdivacky [1]
MFC after: 3 weeks

Add support for TLS in statically linked programs.

make these more useful for lint(1). Minor diff-reductions while I'm
about it.

Drop support for COPY, -c has been the default mode of install(1)
for a long time now.

Approved by: bde

The main reason for this is to reduce diffs between all the crt1.c's.

Assembler macros are tidied up and made as similar as sanely possible.
The macros are translated into C (__inline static) functions for lint.

Declaration orders are made the same.
Declarations are all ISOfied and tidied up.

Comment contents have gratuitous diffs removed.

The net result is a bunch of crt1.c's that are 90% the same.
It may be possible to now encapsulate the differences in one
MD header, and have only one MI crt1.c file (although the macros
to do this may be ugly).

Helpful comments by: obrien, bde
Alpha tested by: des
i386-elf tested by: markm

Use .rodata section for $FreeBSD$.

Fixed CLEANFILES after bsd.lib.mk sweep.

SOBJS are not used here for a long time, and were just
pessimising the `install'.

Major cleanup of bsd.lib.mk.

Get rid of the INTERNALSTATICLIB knob and just use plain INTERNALLIB.
INTERNALLIB now means to build static library only and don't install
anything. Added a NOINSTALLLIB knob for libpam/modules. To not
build any library at all, just do not set LIB.

Revert the last change. The corresponding bsd.lib.mk changes were
already backed out.

Use the simpler NOMAN rather than NOMAN, NOPIC, NOPROFILE, INTERNALLIB.

Do not use __progname directly (except in [gs]etprogname(3)).
Also, make an internal _getprogname() that is used only inside
libc. For libc, getprogname(3) is a weak symbol in case a
function of the same name is defined in userland.

Remove prototype, no other crt1.c has or needs it.

Remove __P() usage.

Remove __P() usage.

Minor style(9) nit + utilize ELF features for the FreeBSD ID.

Sync with other platforms.

Removed duplicate VCS ID tags, as per style(9).

Fix compilation errors by adding forward declarations and fix typo.

The instructions on doing something with src/lib/csu/powerpc.

PowerPC version of the C runtime support.

This is an amalgamation of the NetBSD macppc crt0.c (which the copyright
reflects) and the FreeBSD/Alpha crt1.c.

PowerPC verions of the crt initialization and finalization files required
by the ELF ABI.