u-boot/arch/x86/include/asm/string.h

#ifndef __ASM_I386_STRING_H
#define __ASM_I386_STRING_H

/*
 * We don't do inline string functions, since the
 * optimised inline asm versions are not small.
 */
#undef __HAVE_ARCH_STRNCPY
extern char *strncpy(char *__dest, __const__ char *__src, __kernel_size_t __n);

#undef __HAVE_ARCH_STRRCHR
extern char * strrchr(const char * s, int c);

#undef __HAVE_ARCH_STRCHR
extern char * strchr(const char * s, int c);

#define __HAVE_ARCH_MEMCPY
extern void * memcpy(void *, const void *, __kernel_size_t);

#define __HAVE_ARCH_MEMMOVE
extern void * memmove(void *, const void *, __kernel_size_t);

#undef __HAVE_ARCH_MEMCHR
extern void * memchr(const void *, int, __kernel_size_t);

#define __HAVE_ARCH_MEMSET
extern void * memset(void *, int, __kernel_size_t);

#undef __HAVE_ARCH_MEMZERO
extern void memzero(void *ptr, __kernel_size_t n);

#endif