Commit 0c28130b authored by Paolo 'Blaisorblade' Giarrusso's avatar Paolo 'Blaisorblade' Giarrusso Committed by Linus Torvalds
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[PATCH] x86_64: make string func definition work as intended



In include/asm-x86_64/string.h there are such comments:

/* Use C out of line version for memcmp */
#define memcmp __builtin_memcmp
int memcmp(const void * cs,const void * ct,size_t count);

This would mean that if the compiler does not decide to use __builtin_memcmp,
it emits a call to memcmp to be satisfied by the C out-of-line version in
lib/string.c.  What happens is that after preprocessing, in lib/string.i you
may find the definition of "__builtin_strcmp".

Actually, by accident, in the object you will find the definition of strcmp
and such (maybe a trick intended to redirect calls to __builtin_memcmp to the
default memcmp when the definition is not expanded); however, this particular
case is not a documented feature as far as I can see.

Also, the EXPORT_SYMBOL does not work, so it's duplicated in the arch.

I simply added some #undef to lib/string.c and removed the (now duplicated)
exports in x86-64 and UML/x86_64 subarchs (the second ones are introduced by
another patch I just posted for -mm).
Signed-off-by: default avatarPaolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
CC: Andi Kleen <ak@suse.de>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 23352fc2
......@@ -169,10 +169,6 @@ EXPORT_SYMBOL(rtc_lock);
EXPORT_SYMBOL_GPL(set_nmi_callback);
EXPORT_SYMBOL_GPL(unset_nmi_callback);
#undef memcmp
extern int memcmp(const void *,const void *,__kernel_size_t);
EXPORT_SYMBOL(memcmp);
EXPORT_SYMBOL(register_die_notifier);
#ifdef CONFIG_HAVE_DEC_LOCK
EXPORT_SYMBOL(_atomic_dec_and_lock);
......
......@@ -14,9 +14,6 @@ EXPORT_SYMBOL(__up_wakeup);
/*XXX: we need them because they would be exported by x86_64 */
EXPORT_SYMBOL(__memcpy);
EXPORT_SYMBOL(strcmp);
EXPORT_SYMBOL(strcat);
EXPORT_SYMBOL(strcpy);
/* Networking helper routines. */
/*EXPORT_SYMBOL(csum_partial_copy_from);
......
......@@ -139,35 +139,23 @@ EXPORT_SYMBOL_GPL(unset_nmi_callback);
#undef memmove
#undef memchr
#undef strlen
#undef strcpy
#undef strncmp
#undef strncpy
#undef strchr
#undef strcmp
#undef strcpy
#undef strcat
#undef memcmp
extern void * memset(void *,int,__kernel_size_t);
extern size_t strlen(const char *);
extern void * memmove(void * dest,const void *src,size_t count);
extern char * strcpy(char * dest,const char *src);
extern int strcmp(const char * cs,const char * ct);
extern void *memchr(const void *s, int c, size_t n);
extern void * memcpy(void *,const void *,__kernel_size_t);
extern void * __memcpy(void *,const void *,__kernel_size_t);
extern char * strcat(char *, const char *);
extern int memcmp(const void * cs,const void * ct,size_t count);
EXPORT_SYMBOL(memset);
EXPORT_SYMBOL(strlen);
EXPORT_SYMBOL(memmove);
EXPORT_SYMBOL(strcpy);
EXPORT_SYMBOL(strncmp);
EXPORT_SYMBOL(strncpy);
EXPORT_SYMBOL(strchr);
EXPORT_SYMBOL(strcmp);
EXPORT_SYMBOL(strcat);
EXPORT_SYMBOL(strncat);
EXPORT_SYMBOL(memchr);
EXPORT_SYMBOL(strrchr);
......@@ -175,7 +163,6 @@ EXPORT_SYMBOL(strnlen);
EXPORT_SYMBOL(memscan);
EXPORT_SYMBOL(memcpy);
EXPORT_SYMBOL(__memcpy);
EXPORT_SYMBOL(memcmp);
#ifdef CONFIG_RWSEM_XCHGADD_ALGORITHM
/* prototypes are wrong, these are assembly with custom calling functions */
......
......@@ -65,6 +65,7 @@ EXPORT_SYMBOL(strnicmp);
* @dest: Where to copy the string to
* @src: Where to copy the string from
*/
#undef strcpy
char * strcpy(char * dest,const char *src)
{
char *tmp = dest;
......@@ -132,6 +133,7 @@ EXPORT_SYMBOL(strlcpy);
* @dest: The string to be appended to
* @src: The string to append to it
*/
#undef strcat
char * strcat(char * dest, const char * src)
{
char *tmp = dest;
......@@ -209,6 +211,7 @@ EXPORT_SYMBOL(strlcat);
* @cs: One string
* @ct: Another string
*/
#undef strcmp
int strcmp(const char * cs,const char * ct)
{
register signed char __res;
......@@ -514,6 +517,7 @@ EXPORT_SYMBOL(memmove);
* @ct: Another area of memory
* @count: The size of the area.
*/
#undef memcmp
int memcmp(const void * cs,const void * ct,size_t count)
{
const unsigned char *su1, *su2;
......
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