linux-kernel - [PATCH 08/24] tools: Simplify BITS_PER

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Fri, 15 Jul 2016 17:50:42 -0300
From:	Arnaldo Carvalho de Melo <acme@...nel.org>
To:	Ingo Molnar <mingo@...nel.org>
Cc:	linux-kernel@...r.kernel.org,
	Peter Zijlstra <peterz@...radead.org>,
	Andy Lutomirski <luto@...capital.net>,
	"H . Peter Anvin" <hpa@...or.com>,
	Thomas Gleixner <tglx@...utronix.de>,
	Arnaldo Carvalho de Melo <acme@...hat.com>
Subject: [PATCH 08/24] tools: Simplify BITS_PER_LONG define

From: Peter Zijlstra <peterz@...radead.org>

Do it using (__CHAR_BIT__ * __SIZEOF_LONG__), simpler, works everywhere,
reduces the complexity by ditching CONFIG_64BIT, that was being
synthesized from yet another set of defines, which proved fragile,
breaking the build on linux-next for no obvious reasons.

Committer Note:

Except on:

gcc version 4.1.2 20080704 (Red Hat 4.1.2-55)

Fallback to __WORDSIZE in that case...

Reported-by: Stephen Rothwell <sfr@...b.auug.org.au>
Signed-off-by: Peter Zijlstra <peterz@...radead.org>
Tested-by: Arnaldo Carvalho de Melo <acme@...hat.com>
Cc: Andy Lutomirski <luto@...capital.net>
Cc: H. Peter Anvin <hpa@...or.com>
Cc: Thomas Gleixner <tglx@...utronix.de>
Link: http://lkml.kernel.org/r/20160715072243.GP30154@twins.programming.kicks-ass.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@...hat.com>
---
 tools/include/asm-generic/bitsperlong.h | 23 ++---------------------
 1 file changed, 2 insertions(+), 21 deletions(-)

diff --git a/tools/include/asm-generic/bitsperlong.h b/tools/include/asm-generic/bitsperlong.h
index cfd661c6fc17..45eca517efb3 100644
--- a/tools/include/asm-generic/bitsperlong.h
+++ b/tools/include/asm-generic/bitsperlong.h
@@ -3,31 +3,12 @@
 
 #include <uapi/asm-generic/bitsperlong.h>
 
-/*
- * In the kernel, where this file comes from, we can rely on CONFIG_64BIT,
- * here we have to make amends with what the various compilers provides us
- * to figure out if we're on a 64-bit machine...
- */
 #ifdef __SIZEOF_LONG__
-# if __SIZEOF_LONG__ == 8
-#  define CONFIG_64BIT
-# endif
+#define BITS_PER_LONG (__CHAR_BIT__ * __SIZEOF_LONG__)
 #else
-# ifdef __WORDSIZE
-#  if __WORDSIZE == 64
-#   define CONFIG_64BIT
-#  endif
-# else
-#  error Failed to determine BITS_PER_LONG value
-# endif
+#define BITS_PER_LONG __WORDSIZE
 #endif
 
-#ifdef CONFIG_64BIT
-#define BITS_PER_LONG 64
-#else
-#define BITS_PER_LONG 32
-#endif /* CONFIG_64BIT */
-
 #if BITS_PER_LONG != __BITS_PER_LONG
 #error Inconsistent word size. Check asm/bitsperlong.h
 #endif
-- 
2.7.4