diff --git a/SDKs/darwin/usr/include/string.h b/SDKs/darwin/usr/include/string.h
index 5e91109..bee9d46 100644
--- a/SDKs/darwin/usr/include/string.h
+++ b/SDKs/darwin/usr/include/string.h
@@ -19,6 +19,8 @@
 
 typedef __SIZE_TYPE__ size_t;
 
+int memcmp(const void *, const void *, size_t);
+void *memcpy(void *, const void *, size_t);
 char *strcat(char *, const char *);
 char *strcpy(char *, const char *);
 char *strdup(const char *);
diff --git a/SDKs/linux/usr/include/string.h b/SDKs/linux/usr/include/string.h
index 5e91109..bee9d46 100644
--- a/SDKs/linux/usr/include/string.h
+++ b/SDKs/linux/usr/include/string.h
@@ -19,6 +19,8 @@
 
 typedef __SIZE_TYPE__ size_t;
 
+int memcmp(const void *, const void *, size_t);
+void *memcpy(void *, const void *, size_t);
 char *strcat(char *, const char *);
 char *strcpy(char *, const char *);
 char *strdup(const char *);