linux-toradex.git/Documentation/kbuild/makefiles.txt, branch v2.6.30

kbuild: introduce subdir-ccflags-y

2009-04-19T09:12:12+00:00

Following patch introduce support for setting options
to gcc that has effect for current directory and all
subdirectories.

The typical use case are an architecture or a subsystem that
decide to cover all files with -Werror.
Today alpha, mips and sparc uses -Werror in almost all their
Makefile- with subdir-ccflag-y it is now simpler to do so
as only the top-level directories needs to be covered.

Likewise if we decide to cover a full subsystem such
as net/ with -Werror this is done by adding a single
line to net/Makefile.

Signed-off-by: Sam Ravnborg 
Cc: Ingo Molnar 
Cc: "H. Peter Anvin" 
Cc: Thomas Gleixner

kbuild: introduce destination-y for exported headers

2009-04-11T06:18:08+00:00

xtensa and arm have asked for a possibility to export headers
and locate them in a specific directory when exported.
Introduce destiantion-y to support this.

This patch in additiona adds some limited
documentation for the variables used for exported headers.

Signed-off-by: Sam Ravnborg 
Cc: Oskar Schirmer 
Cc: Mikael Starvik

kbuild: introduce $(kecho) convenience echo

2008-12-03T20:32:00+00:00

There is a bunch of places in the build system where we do 'echo' to show
some nice status lines.  This means we still get output when running in
silent mode.  So declare a new KECHO variable that only does 'echo' when we
are in a suitable verbose build mode.

Signed-off-by: Mike Frysinger 
[sam: added Documentation]
Signed-off-by: Sam Ravnborg

kbuild: cc-cross-prefix spelling

2007-10-22T18:04:37+00:00

Spelling fixes for cc-cross-prefix documentation

Signed-off-by: Geert Uytterhoeven 
Signed-off-by: Sam Ravnborg

kbuild: introduce cc-cross-prefix

2007-10-19T19:46:01+00:00

cc-cross-prefix is useful for the architecture that like
to provide a default CROSS_COMPILE value,
but may have several to select between.

Sample usage:

ifneq ($(SUBARCH),$(ARCH))
        ifeq ($(CROSS_COMPILE),)
               CROSS_COMPILE := $(call cc-cross-prefix, m68k-linux-gnu- m68k-linux-)
        endif
endif

Actual usage by the different archs will taken care of later.

Signed-off-by: Sam Ravnborg

kbuild: introduce ccflags-y, asflags-y and ldflags-y

2007-10-15T20:25:06+00:00

Introduce ccflags-y, asflags-y and ldflags-y so we soon can
deprecate use of EXTRA_CFLAGS, EXTRA_AFLAGS and EXTRA_LDFLAGS.
This patch does not touch any in-tree users - thats next round.
Lets get this committed first and then fix the users of the
soon to be deprecated variants next.

The rationale behind this change is to introduce support for
makefile fragments like:

ccflags-$(CONFIG_WHATEVER_DEBUG) := -DDEBUG

As a replacement for the uglier:
ifeq ($(CONFIG_WHATEVER_DEBUG),y)
        EXTRA_CFLAGS := -DDEBUG
endif

Signed-off-by: Sam Ravnborg

kbuild: enable 'make CPPFLAGS=...' to add additional options to CPP

2007-10-15T20:17:25+00:00

The variable CPPFLAGS is a wellknown variable and the usage by
kbuild may result in unexpected behaviour.

This patch replace use of CPPFLAGS with KBUILD_CPPFLAGS all over the
tree and enabling one to use:
make CPPFLAGS=...
to specify additional CPP commandline options.

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

Signed-off-by: Sam Ravnborg

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

2007-10-15T19:59:31+00:00

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

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

2007-10-14T20:21:35+00:00

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

kbuild: kill EXTRA_ARFLAGS

2007-10-12T19:20:32+00:00

EXTRA_ARFLAGS have never been used so no need to carry
around on this.
A google search did not reveal any external module
using this either.

Signed-off-by: Sam Ravnborg