kbuild: enable 'make AFLAGS=...' to add additional options to AS

The variable AFLAGS is a wellknown variable and the usage by
kbuild may result in unexpected behaviour.
On top of that several people

kbuild: enable 'make AFLAGS=...' to add additional options to AS

The variable AFLAGS is a wellknown variable and the usage by
kbuild may result in unexpected behaviour.
On top of that several people over time has asked for a way to
pass in additional flags to gcc.

This patch replace use of AFLAGS with KBUILD_AFLAGS all over
the tree.

Patch was tested on following architectures:
alpha, arm, i386, x86_64, mips, sparc, sparc64, ia64, m68k, s390

Signed-off-by: Sam Ravnborg <[email protected]>

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kbuild: enable 'make CFLAGS=...' to add additional options to CC

The variable CFLAGS is a wellknown variable and the usage by
kbuild may result in unexpected behaviour.
On top of that several people

kbuild: enable 'make CFLAGS=...' to add additional options to CC

The variable CFLAGS is a wellknown variable and the usage by
kbuild may result in unexpected behaviour.
On top of that several people over time has asked for a way to
pass in additional flags to gcc.

This patch replace use of CFLAGS with KBUILD_CFLAGS all over the
tree and enabling one to use:
make CFLAGS=...
to specify additional gcc commandline options.

One usecase is when trying to find gcc bugs but other
use cases has been requested too.

Patch was tested on following architectures:
alpha, arm, i386, x86_64, mips, sparc, sparc64, ia64, m68k

Test was simple to do a defconfig build, apply the patch and check
that nothing got rebuild.

Signed-off-by: Sam Ravnborg <[email protected]>

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kbuild: New 'cc-fullversion' macro

Prints a six-digit string including the GCC patchlevel. Also fix
the 'usage' comment for cc-version.

Signed-off-by: Segher Boessenkool <[email protected]

kbuild: New 'cc-fullversion' macro

Prints a six-digit string including the GCC patchlevel. Also fix
the 'usage' comment for cc-version.

Signed-off-by: Segher Boessenkool <[email protected]>
Signed-off-by: Sam Ravnborg <[email protected]>

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[PATCH] kbuild: more Makefile cleanups

This adds the remaining changes which should have been part of the
review process.

- the define command is inappropriate (it's primarily for rule
definiti

[PATCH] kbuild: more Makefile cleanups

This adds the remaining changes which should have been part of the
review process.

- the define command is inappropriate (it's primarily for rule
definitions)
- execute commands in the current dir as all other commands
- .*.tmp (but not .*.null) files are also removed up by "make clean"
- printf has other side effects, just use "echo -e"
- proper quoting
- proper indentation

Signed-off-by: Roman Zippel <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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kbuild: fix space for good (take 103)

Michal Ostrowski points out what the real problem was: the spaces at the
start of the definition of the 'checker-shell' make function.

Cc: Michal Ostrowski <mo

kbuild: fix space for good (take 103)

Michal Ostrowski points out what the real problem was: the spaces at the
start of the definition of the 'checker-shell' make function.

Cc: Michal Ostrowski <[email protected]>
Acked-by: David Miller <[email protected]>
Acked-by: Geert Uytterhoeven <[email protected]>
Acked-by: Oleg Verych <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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kbuild: make $(checker-shell ) strip spaces around the result

It looks like GNU make version 3.80 (but apparently not 3.81) adds
leading whitespace to the result of the checker-shell execution. Thi

kbuild: make $(checker-shell ) strip spaces around the result

It looks like GNU make version 3.80 (but apparently not 3.81) adds
leading whitespace to the result of the checker-shell execution. This
strips them off explicitly.

Also, don't bother symlinking the output file to /dev/null. It's likely
as expensive as just writing the temp-file, and we need to remove it
anyway afterwards.

Signed-off-by: Linus Torvalds <[email protected]>

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[PATCH] kbuild, Kbuild.include: avoid using spaces in call arguments

Do not use whitespace in arguments of functions in makefiles, as they
propagate further without notice. Thus we get

+ echo '

[PATCH] kbuild, Kbuild.include: avoid using spaces in call arguments

Do not use whitespace in arguments of functions in makefiles, as they
propagate further without notice. Thus we get

+ echo ' y'

instead of

+ echo y

Fix misleading comments.

Signed-off-by: Oleg Verych <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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[PATCH] kbuild: improve option checking, Kbuild.include cleanup

GNU binutils, root users, tmpfiles, external modules ro builds must
be fixed to do the right thing now.

Cc: Roman Zippel <zippel@li

[PATCH] kbuild: improve option checking, Kbuild.include cleanup

GNU binutils, root users, tmpfiles, external modules ro builds must
be fixed to do the right thing now.

Cc: Roman Zippel <[email protected]>
Cc: Sam Ravnborg <[email protected]>
Cc: Horst Schirmeier <[email protected]>
Cc: Jan Beulich <[email protected]>
Cc: Daniel Drake <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Randy Dunlap <[email protected]>
Signed-off-by: Oleg Verych <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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[PATCH] kbuild: don't put temp files in source

The as-instr/ld-option need to create temporary files, but create them in the
output directory, when compiling external modules. Reformat them a bit a

[PATCH] kbuild: don't put temp files in source

The as-instr/ld-option need to create temporary files, but create them in the
output directory, when compiling external modules. Reformat them a bit and
use $(CC) instead of $(AS) as the former is used by kbuild to assemble files.

Signed-off-by: Roman Zippel <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Jan Beulich <[email protected]>
Cc: Sam Ravnborg <[email protected]>
Cc: <[email protected]>
Cc: Horst Schirmeier <[email protected]>
Cc: Daniel Drake <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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[PATCH] i386/x86-64: Work around gcc bug with noreturn functions in unwinder

Current gcc generates calls not jumps to noreturn functions. When that happens the
return address can point to the next f

[PATCH] i386/x86-64: Work around gcc bug with noreturn functions in unwinder

Current gcc generates calls not jumps to noreturn functions. When that happens the
return address can point to the next function, which confuses the unwinder.

This patch works around it by marking asynchronous exception
frames in contrast normal call frames in the unwind information. Then teach
the unwinder to decode this.

For normal call frames the unwinder now subtracts one from the address which avoids
this problem. The standard libgcc unwinder uses the same trick.

It doesn't include adjustment of the printed address (i.e. for the original
example, it'd still be kernel_math_error+0 that gets displayed, but the
unwinder wouldn't get confused anymore.

This only works with binutils 2.6.17+ and some versions of H.J.Lu's 2.6.16
unfortunately because earlier binutils don't support .cfi_signal_frame

[AK: added automatic detection of the new binutils and wrote description]

Signed-off-by: Jan Beulich <[email protected]>
Signed-off-by: Andi Kleen <[email protected]>

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[PATCH] x86: Detect CFI support in the assembler at runtime

... instead of using a CONFIG option. The config option still controls
if the resulting executable actually has unwind information.

This

[PATCH] x86: Detect CFI support in the assembler at runtime

... instead of using a CONFIG option. The config option still controls
if the resulting executable actually has unwind information.

This is useful to prevent compilation errors when users select
CONFIG_STACK_UNWIND on old binutils and also allows to use
CFI in the future for non kernel debugging applications.

Cc: [email protected]
Cc: [email protected]

Signed-off-by: Andi Kleen <[email protected]>

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kbuild: make V=2 tell why a target is rebuild

tell why a a target got build
enabled by make V=2
Output (listed in the order they are checked):
(1) - due to target is PHONY

kbuild: make V=2 tell why a target is rebuild

tell why a a target got build
enabled by make V=2
Output (listed in the order they are checked):
(1) - due to target is PHONY
(2) - due to target missing
(3) - due to: file1.h file2.h
(4) - due to command line change
(5) - due to missing .cmd file
(6) - due to target not in $(targets)
(1) We always build PHONY targets
(2) No target, so we better build it
(3) Prerequisite is newer than target
(4) The command line stored in the file named dir/.target.cmd
differed from actual command line. This happens when compiler
options changes
(5) No dir/.target.cmd file (used to store command line)
(6) No dir/.target.cmd file and target not listed in $(targets)
This is a good hint that there is a bug in the kbuild file

This patch is inspired by a patch from: Milton Miller <[email protected]>

Cc: Milton Miller <[email protected]>
Signed-off-by: Sam Ravnborg <[email protected]>

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kbuild: consistently decide when to rebuild a target

Consistently decide when to rebuild a target across all of
if_changed, if_changed_dep, if_changed_rule.
PHONY targets are now treated alike (igno

kbuild: consistently decide when to rebuild a target

Consistently decide when to rebuild a target across all of
if_changed, if_changed_dep, if_changed_rule.
PHONY targets are now treated alike (ignored) for all targets

While add it make Kbuild.include almost readable by factoring out a few
bits to some common variables and reuse this in Makefile.build.

Signed-off-by: Sam Ravnborg <[email protected]>

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kbuild: always use $(CC) for $(call cc-version)

The possibility to specify an optional parameter did not work out as
expected and it was not used - so remove the possibility.

Signed-off-by: Sam Rav

kbuild: always use $(CC) for $(call cc-version)

The possibility to specify an optional parameter did not work out as
expected and it was not used - so remove the possibility.

Signed-off-by: Sam Ravnborg <[email protected]>

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[PATCH] vDSO hash-style fix

The latest toolchains can produce a new ELF section in DSOs and
dynamically-linked executables. The new section ".gnu.hash" replaces
".hash", and allows for more efficie

[PATCH] vDSO hash-style fix

The latest toolchains can produce a new ELF section in DSOs and
dynamically-linked executables. The new section ".gnu.hash" replaces
".hash", and allows for more efficient runtime symbol lookups by the
dynamic linker. The new ld option --hash-style={sysv|gnu|both} controls
whether to produce the old ".hash", the new ".gnu.hash", or both. In some
new systems such as Fedora Core 6, gcc by default passes --hash-style=gnu
to the linker, so that a standard invocation of "gcc -shared" results in
producing a DSO with only ".gnu.hash". The new ".gnu.hash" sections need
to be dealt with the same way as ".hash" sections in all respects; only the
dynamic linker cares about their contents. To work with older dynamic
linkers (i.e. preexisting releases of glibc), a binary must have the old
".hash" section. The --hash-style=both option produces binaries that a new
dynamic linker can use more efficiently, but an old dynamic linker can
still handle.

The new section runs afoul of the custom linker scripts used to build vDSO
images for the kernel. On ia64, the failure mode for this is a boot-time
panic because the vDSO's PT_IA_64_UNWIND segment winds up ill-formed.

This patch addresses the problem in two ways.

First, it mentions ".gnu.hash" in all the linker scripts alongside ".hash".
This produces correct vDSO images with --hash-style=sysv (or old tools),
with --hash-style=gnu, or with --hash-style=both.

Second, it passes the --hash-style=sysv option when building the vDSO
images, so that ".gnu.hash" is not actually produced. This is the most
conservative choice for compatibility with any old userland. There is some
concern that some ancient glibc builds (though not any known old production
system) might choke on --hash-style=both binaries. The optimizations
provided by the new style of hash section do not really matter for a DSO
with a tiny number of symbols, as the vDSO has. If someone wants to use
=gnu or =both for their vDSO builds and worry less about that
compatibility, just change the option and the linker script changes will
make any choice work fine.

Signed-off-by: Roland McGrath <[email protected]>
Cc: "Luck, Tony" <[email protected]>
Cc: Kyle McMartin <[email protected]>
Cc: Paul Mackerras <[email protected]>
Cc: Benjamin Herrenschmidt <[email protected]>
Cc: Jeff Dike <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Sam Ravnborg <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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kbuild: fix ia64 breakage after introducing make -rR

kbuild used $¤(*F to get filename of target without extension.
This was used in several places all over kbuild, but introducing
make -rR broke hi

kbuild: fix ia64 breakage after introducing make -rR

kbuild used $¤(*F to get filename of target without extension.
This was used in several places all over kbuild, but introducing
make -rR broke his for all cases where we specified full path to
target/prerequsite. It is assumed that make -rR disables old style
suffix-rules which is why is suddenly failed.

ia64 was impacted by this change because several div* routines in
arch/ia64/lib are build using explicit paths and then kbuild failed.

Thanks to David Mosberger-Tang <[email protected]> for an explanation
what was the root-cause and for testing on ia64.

This patch also fixes two uses of $(*F) in arch/um

Signed-off-by: Sam Ravnborg <[email protected]>

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Revert "kbuild: fix make -rR breakage"

This reverts commit e5c44fd88c146755da6941d047de4d97651404a9.

Thanks to Daniel Ritz and Michal Piotrowski for noticing the problem.

Daniel says:

"[The] re

Revert "kbuild: fix make -rR breakage"

This reverts commit e5c44fd88c146755da6941d047de4d97651404a9.

Thanks to Daniel Ritz and Michal Piotrowski for noticing the problem.

Daniel says:

"[The] reason is a recent change that made modules always shows as
module.mod. it breaks modprobe and probably many scripts..besides
lsmod looking horrible

stuff like this in modprobe.conf:
install pcmcia_core /sbin/modprobe --ignore-install pcmcia_core; /sbin/modprobe pcmcia
makes modprobe fork/exec endlessly calling itself...until oom
interrupts it"

Signed-off-by: Linus Torvalds <[email protected]>

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kbuild: fix make -rR breakage

make failed to supply the filename when using make -rR and using $(*F)
to get target filename without extension.
This bug was not reproduceable in small scale but using

kbuild: fix make -rR breakage

make failed to supply the filename when using make -rR and using $(*F)
to get target filename without extension.
This bug was not reproduceable in small scale but using:
$(basename $(notdir $@)) fixes it with same functionality.

Signed-off-by: Sam Ravnborg <[email protected]>

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kbuild: properly pass options to hostcc when doing make O=..

This fix a longstanding bug where proper options was not
passed to hostcc in case of a make O=.. build.
This bug showed up in (not yet me

kbuild: properly pass options to hostcc when doing make O=..

This fix a longstanding bug where proper options was not
passed to hostcc in case of a make O=.. build.
This bug showed up in (not yet merged) klibc, and is not known
to have any counterpart in-kernel.
Fixed by moving the flags macro to Kbuild.include so it can be used
by both Makefile.lib and Makefile.host.

Signed-off-by: Sam Ravnborg <[email protected]>

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kbuild: change kbuild to not rely on incorrect GNU make behavior

The kbuild system takes advantage of an incorrect behavior in GNU make.
Once this behavior is fixed, all files in the kernel rebuild

kbuild: change kbuild to not rely on incorrect GNU make behavior

The kbuild system takes advantage of an incorrect behavior in GNU make.
Once this behavior is fixed, all files in the kernel rebuild every time,
even if nothing has changed. This patch ensures kbuild works with both
the incorrect and correct behaviors of GNU make.

For more details on the incorrect behavior, see:

http://lists.gnu.org/archive/html/bug-make/2006-03/msg00003.html

Changes in this patch:
- Keep all targets that are to be marked .PHONY in a variable, PHONY.
- Add .PHONY: $(PHONY) to mark them properly.
- Remove any $(PHONY) files from the $? list when determining whether
targets are up-to-date or not.

Signed-off-by: Paul Smith <[email protected]>
Signed-off-by: Sam Ravnborg <[email protected]>

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kbuild: fix comment in Kbuild.include

Noted by Olaf Hering <[email protected]>

Signed-off-by: Sam Ravnborg <[email protected]>

kbuild: consolidate command line escaping

While the recent change to also escape # symbols when storing C-file
compilation command lines was helpful, it should be in effect for all
command lines, as

kbuild: consolidate command line escaping

While the recent change to also escape # symbols when storing C-file
compilation command lines was helpful, it should be in effect for all
command lines, as much as the dollar escaping should be in effect for
C-source compilation commands. Additionally, for better readability and
maintenance, consolidating all the escaping (single quotes, dollars,
and now sharps) was also desirable.

Signed-Off-By: Jan Beulich <[email protected]>
Signed-off-by: Sam Ravnborg <[email protected]>

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kbuild: make cc-version available in kbuild files

Move $(CC) support functions to Kbuild.include so they are available
in the kbuild files.
In addition the following was done:
o as-option documente

kbuild: make cc-version available in kbuild files

Move $(CC) support functions to Kbuild.include so they are available
in the kbuild files.
In addition the following was done:
o as-option documented in Documentation/kbuild/makefiles.txt
o Moved documentation to new section to match
new scope of functions
o added cc-ifversion used to conditionally select a text string
dependent on actual $(CC) version
o documented cc-ifversion
o change so Kbuild.include is read before the kbuild file

Signed-off-by: Sam Ravnborg <[email protected]>

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kbuild: introduce escsq to escapre single quotes

This makes things a little bit more reader friendly and gvim is less
confused.

Signed-off-by: Sam Ravnborg <[email protected]>

kbuild: add objectify

Use foo := $(call objectify, $(foo)) to prefix $(foo) with $(obj)/ unless
$(foo) is an absolute path.
For now no in-tree users - soon to come.

Signed-off-by: Sam Ravnborg <sam

kbuild: add objectify

Use foo := $(call objectify, $(foo)) to prefix $(foo) with $(obj)/ unless
$(foo) is an absolute path.
For now no in-tree users - soon to come.

Signed-off-by: Sam Ravnborg <[email protected]>

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