From 975dcf140bd307b431aff7b6d671155c796cfe5e Mon Sep 17 00:00:00 2001
From: Laura Abbott <labbott@redhat.com>
Date: Sat, 28 Jan 2017 16:13:49 +0100
Subject: [PATCH] Work around for gcc7 and arm64
Originally proposed by Will Deacon <will.deacon@arm.com>
http://lists.infradead.org/pipermail/linux-arm-kernel/2016-October/462224.html
Signed-off-by: Laura Abbott <labbott@redhat.com>
---
include/linux/log2.h | 13 ++-----------
1 file changed, 2 insertions(+), 11 deletions(-)
diff --git a/include/linux/log2.h b/include/linux/log2.h
index fd7ff3d91e6a..1ab22b79681e 100644
--- a/include/linux/log2.h
+++ b/include/linux/log2.h
@@ -16,12 +16,6 @@
#include <linux/bitops.h>
/*
- * deal with unrepresentable constant logarithms
- */
-extern __attribute__((const, noreturn))
-int ____ilog2_NaN(void);
-
-/*
* non-constant log of base 2 calculators
* - the arch may override these in asm/bitops.h if they can be implemented
* more efficiently than using fls() and fls64()
@@ -85,7 +79,7 @@ unsigned long __rounddown_pow_of_two(unsigned long n)
#define ilog2(n) \
( \
__builtin_constant_p(n) ? ( \
- (n) < 1 ? ____ilog2_NaN() : \
+ (n) < 1 ? 0 : \
(n) & (1ULL << 63) ? 63 : \
(n) & (1ULL << 62) ? 62 : \
(n) & (1ULL << 61) ? 61 : \
@@ -149,9 +143,7 @@ unsigned long __rounddown_pow_of_two(unsigned long n)
(n) & (1ULL << 3) ? 3 : \
(n) & (1ULL << 2) ? 2 : \
(n) & (1ULL << 1) ? 1 : \
- (n) & (1ULL << 0) ? 0 : \
- ____ilog2_NaN() \
- ) : \
+ 0 ) : \
(sizeof(n) <= 4) ? \
__ilog2_u32(n) : \
__ilog2_u64(n) \
@@ -194,7 +186,6 @@ unsigned long __rounddown_pow_of_two(unsigned long n)
* @n: parameter
*
* The first few values calculated by this routine:
- * ob2(0) = 0
* ob2(1) = 0
* ob2(2) = 1
* ob2(3) = 2
--
2.11.0