Disable the new -Wunused-but-set-variable that was added in gcc 4.6.0
It produces more false positives than useful warnings.

This can still be enabled using W=1
Signed-off-by: NDave Jones <davej@redhat.com>
Acked-by: NSam Ravnborg <sam@ravnborg.org>
Tested-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NMichal Marek <mmarek@suse.cz>

There is an increasing amount of header files
shared between individual architectures in asm-generic.
To avoid a lot of dummy wrapper files that just
include the corresponding file in asm-generic provide
some basic support in kbuild for this.

With the following patch an architecture can maintain
a list of files in the file arch/$(ARCH)/include/asm/Kbuild

To use a generic file just add:

        generic-y += <name-of-header-file.h>

For each file listed kbuild will generate the necessary
wrapper in arch/$(ARCH)/include/generated/asm.

When installing userspace headers a wrapper is likewise created.

The original inspiration for this came from the unicore32
patchset - although a different method is used.

The patch includes several improvements from Arnd Bergmann.
Michael Marek contributed Makefile.asm-generic.

Remis Baima did an intial implementation along to achive
the same - see https://patchwork.kernel.org/patch/13352/Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Acked-by: NGuan Xuetao <guanxuetao@mprc.pku.edu.cn>
Tested-by: NGuan Xuetao <guanxuetao@mprc.pku.edu.cn>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Cc: Remis Lima Baima <remis.developer@googlemail.com>
Signed-off-by: NMichal Marek <mmarek@suse.cz>

Building a kernel with "make W=1" produces far too much noise to be
useful.

Divide the warning options in three groups:

    W=1 - warnings that may be relevant and does not occur too often
    W=2 - warnings that occur quite often but may still be relevant
    W=3 - the more obscure warnings, can most likely be ignored

When building the whole kernel, those levels produce:

W=1 - 4859 warnings
W=2 - 1394 warnings
W=3 - 86666 warnings

respectively. Warnings have been counted with Geert's script at

http://www.kernel.org/pub/linux/kernel/people/geert/linux-log/linux-log-summary.pl

Many warnings occur from .h files so fixing one file may have a nice
effect on the total number of warnings.

With these changes I am actually tempted to try W=1 now and then.
Previously there was just too much noise.

Borislav:

- make the W= levels exclusive
- move very noisy and making little sense for the kernel warnings to W=3
- drop -Woverlength-strings due to useless warning message
- copy explanatory text for the different warning levels to 'make help'
- recount warnings per level
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NBorislav Petkov <bp@alien8.de>
Cc: Dave Jones <davej@redhat.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NMichal Marek <mmarek@suse.cz>

The D option of ar is only available in newer versions.
Signed-off-by: NMichal Marek <mmarek@suse.cz>

At the moment we have the CONFIG_KALLSYMS_EXTRA_PASS Kconfig switch,
which users can enable or disable while configuring the kernel. This
option is then used by 'make' to determine whether an extra kallsyms
pass is needed or not.

However, this approach is not nice and confusing, and this patch moves
CONFIG_KALLSYMS_EXTRA_PASS from Kconfig to Makefile instead. The
rationale is below.

1. CONFIG_KALLSYMS_EXTRA_PASS is really about the build time, not
   run-time. There is no real need for it to be in Kconfig. It is
   just an additional work-around which should be used only in rare
   cases, when someone breaks kallsyms, so Kbuild/Makefile is much
   better place for this option.
2. Grepping CONFIG_KALLSYMS_EXTRA_PASS shows that many defconfigs have
   it enabled, probably not because they try to work-around a kallsyms
   bug, but just because the Kconfig help text is confusing and does
   not really make it clear that this option should not be used unless
   except when kallsyms is broken.
3. And since many people have CONFIG_KALLSYMS_EXTRA_PASS enabled in
   their Kconfig, we do might fail to notice kallsyms bugs in time. E.g.,
   many testers use "make allyesconfig" to test builds, which will enable
   CONFIG_KALLSYMS_EXTRA_PASS and kallsyms breakage will not be noticed.

To address that, this patch:

1. Kills CONFIG_KALLSYMS_EXTRA_PASS
2. Changes Makefile so that people can use "make KALLSYMS_EXTRA_PASS=1"
   to enable the extra pass if needed. Additionally, they may define
   KALLSYMS_EXTRA_PASS as an environment variable.
3. By default KALLSYMS_EXTRA_PASS is disabled and if kallsyms has issues,
   "make" should print a warning and suggest using KALLSYMS_EXTRA_PASS
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>
[mmarek: Removed make help text, is not necessary]
Signed-off-by: NMichal Marek <mmarek@suse.cz>

While changing our build system over to use the headers_install target
as part of our klibc build, the following message started showing up in
our logs:

make[2]: `scripts/unifdef' is up to date.

It turns out that the build blindly invokes a recursive make on this
target, which causes make to emit this message when the target is
already up to date.  This isn't seen for most targets as the rest of the
build relies primarily on the default target and on PHONY targets when
invoking make recursively.

Silence the above message when building unifdef as part of
headers_install by hiding it behind a new PHONY target called
"build_unifdef" that has an empty recipe.
Signed-off-by: NMike Waychison <mikew@google.com>
Acked-by: NWANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: NMichal Marek <mmarek@suse.cz>

Add a 'W=1' Makefile switch which adds additional checking per build
object.

The idea behind this option is targeted at developers who, in the
process of writing their code, want to do the occasional

make W=1 [target.o]

and let gcc do more extensive code checking for them. Then, they
could eyeball the output for valid gcc warnings about various
bugs/discrepancies which are not reported during the normal build
process.

For more background information and a use case, read through this
thread: http://marc.info/?l=kernel-janitors&m=129802065918147&w=2

Cc: Michal Marek <mmarek@suse.cz>
Cc: linux-kbuild@vger.kernel.org
Acked-by: NSam Ravnborg <sam@ravnborg.org>
Acked-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NBorislav Petkov <bp@alien8.de>
Signed-off-by: NMichal Marek <mmarek@suse.cz>

Signed-off-by: NGilles Espinasse <g.esp@free.fr>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

GNU GLOBAL (http://www.gnu.org/software/global/) is a source code tagging system
It is really cheap to support it in kbuild system.
Signed-off-by: NJianbin Kang <kjbmail@gmail.com>
Signed-off-by: NMichal Marek <mmarek@suse.cz>

If you try to build a kernel with KCONFIG_CONFIG set (to a value
not equal to .config) and that config sets CONFIG_IKCONFIG then the
build will fail with:

make[1]: *** No rule to make target `.config', needed by \
`kernel/config_data.gz'.  Stop.

because the kernel/Makefile contains a direct reference to .config.

This issue has been present since the introduction of KCONFIG_CONFIG
in 14cdd3c4.
Signed-off-by: NBen Gardiner <bengardiner@nanometrics.ca>
CC: Roman Zippel <zippel@linux-m68k.org>
CC: Michal Marek <mmarek@suse.cz>
Reviewed-by: NMichal Marek <mmarek@suse.cz>
Signed-off-by: NMichal Marek <mmarek@suse.cz>

Add 'sparc32' ARCH target to test all{yes,mod}config for 32-bit build.
Signed-off-by: NNamhyung Kim <namhyung@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The config option used by archs to let the build system know that
the C version of the recordmcount works for said arch is currently
called HAVE_C_MCOUNT_RECORD which enables BUILD_C_RECORDMCOUNT. To
be more consistent with the name that all archs may use, it has been
renamed to HAVE_C_RECORDMCOUNT. This will be less confusing since
we are building a C recordmcount and not a mcount_record.
Suggested-by: NIngo Molnar <mingo@elte.hu>
Cc: <linux-arch@vger.kernel.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: linux-kbuild@vger.kernel.org
Cc: John Reiser <jreiser@bitwagon.com>
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

This patch adds the support for the C version of recordmcount and
compile times show ~ 12% improvement.

After verifying this works, other archs can add:

 HAVE_C_MCOUNT_RECORD

in its Kconfig and it will use the C version of recordmcount
instead of the perl version.

Cc: <linux-arch@vger.kernel.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: linux-kbuild@vger.kernel.org
Cc: John Reiser <jreiser@bitwagon.com>
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

base patch to implement 'jump labeling'. Based on a new 'asm goto' inline
assembly gcc mechanism, we can now branch to labels from an 'asm goto'
statment. This allows us to create a 'no-op' fastpath, which can subsequently
be patched with a jump to the slowpath code. This is useful for code which
might be rarely used, but which we'd like to be able to call, if needed.
Tracepoints are the current usecase that these are being implemented for.
Acked-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NJason Baron <jbaron@redhat.com>
LKML-Reference: <ee8b3595967989fdaf84e698dc7447d315ce972a.1284733808.git.jbaron@redhat.com>

[ cleaned up some formating ]
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

The list of patterns for the external modules case was constantly
lagging behind.
Signed-off-by: NMichal Marek <mmarek@suse.cz>