Replace "extern inline" with "static inline"

A number of headers define functions as "extern inline" which is
causing problems with gcc5.  The reason is that starting with
version 5.1, gcc defaults to the standard C99 semantics for the
inline keyword.

Under the traditional GNU inline semantics, an "extern inline"
function would never create an external definition, the same
as inline *without* extern in C99.  In C99, and "extern inline"
definition is simply an external definition with an inline hint.
In short, the meanings of inline with and without extern are
swapped between GNU and C99.

The upshot is that all these definitions in header files create
an external definition wherever those headers are included,
resulting in multiple definition errors at link time.

Changing all these functions to "static inline" fixes the problem
since this works as desired in all gcc versions.  Although the
semantics are slightly different (a static inline definition may
result in an actual function being emitted), it works as intended
in practice.

This patch also removes extern prototype declarations for the
changed functions where they existed.

Signed-off-by: Mans Rullgard <mans@mansr.com>

1 files changed, 14 insertions, 21 deletions

diff --git a/arch/powerpc/include/asm/bitops.h b/arch/powerpc/include/asm/bitops.h
index 14217ef751..96491b6e4e 100644
--- a/arch/powerpc/include/asm/bitops.h
+++ b/arch/powerpc/include/asm/bitops.h
@@ -8,13 +8,6 @@
 #include <asm/byteorder.h>
 #include <asm-generic/bitops/__ffs.h>
 
-extern void set_bit(int nr, volatile void *addr);
-extern void clear_bit(int nr, volatile void *addr);
-extern void change_bit(int nr, volatile void *addr);
-extern int test_and_set_bit(int nr, volatile void *addr);
-extern int test_and_clear_bit(int nr, volatile void *addr);
-extern int test_and_change_bit(int nr, volatile void *addr);
-
 /*
  * Arguably these bit operations don't imply any memory barrier or
  * SMP ordering, but in fact a lot of drivers expect them to imply
@@ -35,7 +28,7 @@ extern int test_and_change_bit(int nr, volatile void *addr);
  * These used to be if'd out here because using : "cc" as a constraint
  * resulted in errors from egcs.  Things may be OK with gcc-2.95.
  */
-extern __inline__ void set_bit(int nr, volatile void * addr)
+static __inline__ void set_bit(int nr, volatile void * addr)
 {
 	unsigned long old;
 	unsigned long mask = 1 << (nr & 0x1f);
@@ -52,7 +45,7 @@ extern __inline__ void set_bit(int nr, volatile void * addr)
 	: "cc" );
 }
 
-extern __inline__ void clear_bit(int nr, volatile void *addr)
+static __inline__ void clear_bit(int nr, volatile void *addr)
 {
 	unsigned long old;
 	unsigned long mask = 1 << (nr & 0x1f);
@@ -69,7 +62,7 @@ extern __inline__ void clear_bit(int nr, volatile void *addr)
 	: "cc");
 }
 
-extern __inline__ void change_bit(int nr, volatile void *addr)
+static __inline__ void change_bit(int nr, volatile void *addr)
 {
 	unsigned long old;
 	unsigned long mask = 1 << (nr & 0x1f);
@@ -86,7 +79,7 @@ extern __inline__ void change_bit(int nr, volatile void *addr)
 	: "cc");
 }
 
-extern __inline__ int test_and_set_bit(int nr, volatile void *addr)
+static __inline__ int test_and_set_bit(int nr, volatile void *addr)
 {
 	unsigned int old, t;
 	unsigned int mask = 1 << (nr & 0x1f);
@@ -105,7 +98,7 @@ extern __inline__ int test_and_set_bit(int nr, volatile void *addr)
 	return (old & mask) != 0;
 }
 
-extern __inline__ int test_and_clear_bit(int nr, volatile void *addr)
+static __inline__ int test_and_clear_bit(int nr, volatile void *addr)
 {
 	unsigned int old, t;
 	unsigned int mask = 1 << (nr & 0x1f);
@@ -124,7 +117,7 @@ extern __inline__ int test_and_clear_bit(int nr, volatile void *addr)
 	return (old & mask) != 0;
 }
 
-extern __inline__ int test_and_change_bit(int nr, volatile void *addr)
+static __inline__ int test_and_change_bit(int nr, volatile void *addr)
 {
 	unsigned int old, t;
 	unsigned int mask = 1 << (nr & 0x1f);
@@ -144,7 +137,7 @@ extern __inline__ int test_and_change_bit(int nr, volatile void *addr)
 }
 #endif /* __INLINE_BITOPS */
 
-extern __inline__ int test_bit(int nr, __const__ volatile void *addr)
+static __inline__ int test_bit(int nr, __const__ volatile void *addr)
 {
 	__const__ unsigned int *p = (__const__ unsigned int *) addr;
 
@@ -153,7 +146,7 @@ extern __inline__ int test_bit(int nr, __const__ volatile void *addr)
 
 /* Return the bit position of the most significant 1 bit in a word */
 /* - the result is undefined when x == 0 */
-extern __inline__ int __ilog2(unsigned int x)
+static __inline__ int __ilog2(unsigned int x)
 {
 	int lz;
 
@@ -161,7 +154,7 @@ extern __inline__ int __ilog2(unsigned int x)
 	return 31 - lz;
 }
 
-extern __inline__ int ffz(unsigned int x)
+static __inline__ int ffz(unsigned int x)
 {
 	if ((x = ~x) == 0)
 		return 32;
@@ -217,7 +210,7 @@ static inline int fls64(__u64 x)
  * the libc and compiler builtin ffs routines, therefore
  * differs in spirit from the above ffz (man ffs).
  */
-extern __inline__ int ffs(int x)
+static __inline__ int ffs(int x)
 {
 	return __ilog2(x & -x) + 1;
 }
@@ -241,7 +234,7 @@ extern __inline__ int ffs(int x)
 #define find_first_zero_bit(addr, size) \
 	find_next_zero_bit((addr), (size), 0)
 
-extern __inline__ unsigned long find_next_zero_bit(void * addr,
+static __inline__ unsigned long find_next_zero_bit(void * addr,
 	unsigned long size, unsigned long offset)
 {
 	unsigned int * p = ((unsigned int *) addr) + (offset >> 5);
@@ -289,7 +282,7 @@ found_middle:
 #define ext2_clear_bit(nr, addr)	test_and_clear_bit((nr) ^ 0x18, addr)
 
 #else
-extern __inline__ int ext2_set_bit(int nr, void * addr)
+static __inline__ int ext2_set_bit(int nr, void * addr)
 {
 	int		mask;
 	unsigned char	*ADDR = (unsigned char *) addr;
@@ -302,7 +295,7 @@ extern __inline__ int ext2_set_bit(int nr, void * addr)
 	return oldbit;
 }
 
-extern __inline__ int ext2_clear_bit(int nr, void * addr)
+static __inline__ int ext2_clear_bit(int nr, void * addr)
 {
 	int		mask;
 	unsigned char	*ADDR = (unsigned char *) addr;
@@ -316,7 +309,7 @@ extern __inline__ int ext2_clear_bit(int nr, void * addr)
 }
 #endif	/* __KERNEL__ */
 
-extern __inline__ int ext2_test_bit(int nr, __const__ void * addr)
+static __inline__ int ext2_test_bit(int nr, __const__ void * addr)
 {
 	__const__ unsigned char	*ADDR = (__const__ unsigned char *) addr;