Commit Graph

6 Commits

Author SHA1 Message Date
David Rientjes
0d7ebbbc6e compiler: introduce __used and __maybe_unused
__used is defined to be __attribute__((unused)) for all pre-3.3 gcc
compilers to suppress warnings for unused functions because perhaps they
are referenced only in inline assembly.  It is defined to be
__attribute__((used)) for gcc 3.3 and later so that the code is still
emitted for such functions.

__maybe_unused is defined to be __attribute__((unused)) for both function
and variable use if it could possibly be unreferenced due to the evaluation
of preprocessor macros.  Function prototypes shall be marked with
__maybe_unused if the actual definition of the function is dependant on
preprocessor macros.

No update to compiler-intel.h is necessary because ICC supports both
__attribute__((used)) and __attribute__((unused)) as specified by the gcc
manual.

__attribute_used__ is deprecated and will be removed once all current
code is converted to using __used.

Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Adrian Bunk <bunk@stusta.de>
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-09 12:30:56 -07:00
Rusty Russell
c5e631cf65 ARRAY_SIZE: check for type
We can use a gcc extension to ensure that ARRAY_SIZE() is handed an array,
not a pointer.  This is especially important when code is changed from a
fixed array to a pointer.  I assume the Intel compiler doesn't support
__builtin_types_compatible_p.

[jdike@addtoit.com: uml: update UML definition of ARRAY_SIZE]
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-07 12:13:00 -07:00
Robert P. J. Day
82ddcb0405 [PATCH] extend the set of "__attribute__" shortcut macros
Extend the set of "__attribute__" shortcut macros, and remove identical
(and now superfluous) definitions from a couple of source files.

based on a page at robert love's blog:

	http://rlove.org/log/2005102601

extend the set of shortcut macros defined in compiler-gcc.h with the
following:

#define __packed                       __attribute__((packed))
#define __weak                         __attribute__((weak))
#define __naked                        __attribute__((naked))
#define __noreturn                     __attribute__((noreturn))
#define __pure                         __attribute__((pure))
#define __aligned(x)                   __attribute__((aligned(x)))
#define __printf(a,b)                  __attribute__((format(printf,a,b)))

Once these are in place, it's up to subsystem maintainers to decide if they
want to take advantage of them.  there is already a strong precedent for
using shortcuts like this in the source tree.

The ones that might give people pause are "__aligned" and "__printf", but
shortcuts for both of those are already in use, and in some ways very
confusingly.  note the two very different definitions for a macro named
"ALIGNED":

  drivers/net/sgiseeq.c:#define ALIGNED(x) ((((unsigned long)(x)) + 0xf) & ~(0xf))
  drivers/scsi/ultrastor.c:#define ALIGNED(x) __attribute__((aligned(x)))

also:

  include/acpi/platform/acgcc.h:
    #define ACPI_PRINTF_LIKE(c) __attribute__ ((__format__ (__printf__, c, c+1)))

Given the precedent, then, it seems logical to at least standardize on a
consistent set of these macros.

Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11 10:51:35 -08:00
Anton Blanchard
c8d52465f9 [PATCH] Work around ppc64 compiler bug
In the process of optimising our per cpu data code, I found a ppc64
compiler bug that has been around forever. Basically the current
RELOC_HIDE can end up trashing r30. Details of the bug can be found at

  http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25572

This bug is present in all compilers before 4.1. It is masked by the
fact that our current per cpu data code is inefficient and causes
other loads that end up marking r30 as used.

A workaround identified by Alan Modra is to use the =r asm constraint
instead of =g.

Signed-off-by: Anton Blanchard <anton@samba.org>
[ Verified that this makes no real difference on x86[-64] */
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-10 08:32:35 -08:00
Andrew Morton
a136564702 [PATCH] remove gcc-2 checks
Remove various things which were checking for gcc-1.x and gcc-2.x compilers.

From: Adrian Bunk <bunk@stusta.de>

    Some documentation updates and removes some code paths for gcc < 3.2.

Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 20:14:02 -08:00
Linus Torvalds
1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00