diff --git a/include/msvcrt/corecrt_wstring.h b/include/msvcrt/corecrt_wstring.h
index 8485716e301..10ab894328f 100644
--- a/include/msvcrt/corecrt_wstring.h
+++ b/include/msvcrt/corecrt_wstring.h
@@ -21,6 +21,7 @@ _ACRTIMP errno_t __cdecl memcpy_s(void*,size_t,const void*,size_t);
 _ACRTIMP void*   __cdecl memset(void*,int,size_t);
 _ACRTIMP void*   __cdecl _memccpy(void*,const void*,int,unsigned int);
 _ACRTIMP int     __cdecl _memicmp(const void*,const void*,unsigned int);
+_ACRTIMP int     __cdecl _memicmp_l(const void*,const void*,unsigned int,_locale_t);
 
 static inline int memicmp(const void* s1, const void* s2, size_t len) { return _memicmp(s1, s2, len); }
 static inline void* memccpy(void *s1, const void *s2, int c, size_t n) { return _memccpy(s1, s2, c, n); }
diff --git a/include/msvcrt/memory.h b/include/msvcrt/memory.h
index 17677f47a8f..21198e8f8bf 100644
--- a/include/msvcrt/memory.h
+++ b/include/msvcrt/memory.h
@@ -24,6 +24,7 @@ errno_t __cdecl memcpy_s(void*,size_t,const void*,size_t);
 void*   __cdecl memset(void*,int,size_t);
 void*   __cdecl _memccpy(void*,const void*,int,unsigned int);
 int     __cdecl _memicmp(const void*,const void*,unsigned int);
+int     __cdecl _memicmp_l(const void*,const void*,unsigned int,_locale_t);
 
 static inline int memicmp(const void* s1, const void* s2, size_t len) { return _memicmp(s1, s2, len); }
 static inline void* memccpy(void *s1, const void *s2, int c, size_t n) { return _memccpy(s1, s2, c, n); }