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[PATCH] x86_64: make string func definition work as intended

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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: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
CC: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Paolo 'Blaisorblade' Giarrusso
2005-05-05 16:15:17 -07:00
committed by Linus Torvalds
parent 23352fc252
commit 0c28130b5c
4 changed files with 4 additions and 20 deletions
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4
lib/string.c
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@ -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;