diff --git a/gcc/gcc/config/aarch64/aarch64.h b/gcc/gcc/config/aarch64/aarch64.h
index 976f9afae5..736b83ff0b 100644
--- a/gcc/gcc/config/aarch64/aarch64.h
+++ b/gcc/gcc/config/aarch64/aarch64.h
@@ -1000,7 +1000,7 @@ extern const char *aarch64_rewrite_mcpu (int argc, const char **argv);
 #define MCPU_TO_MARCH_SPEC_FUNCTIONS \
   { "rewrite_mcpu", aarch64_rewrite_mcpu },
 
-#if defined(__aarch64__)
+#if defined(__aarch64__) && ! defined(__APPLE__)
 extern const char *host_detect_local_cpu (int argc, const char **argv);
 #define HAVE_LOCAL_CPU_DETECT
 # define EXTRA_SPEC_FUNCTIONS						\
diff --git a/gcc/gcc/config/host-darwin.c b/gcc/gcc/config/host-darwin.c
index 8f700eec85..b737abc006 100644
--- a/gcc/gcc/config/host-darwin.c
+++ b/gcc/gcc/config/host-darwin.c
@@ -22,6 +22,8 @@
 #include "coretypes.h"
 #include "diagnostic-core.h"
 #include "config/host-darwin.h"
+#include "hosthooks.h"
+#include "hosthooks-def.h"
 
 /* Yes, this is really supposed to work.  */
 static char pch_address_space[1024*1024*1024] __attribute__((aligned (4096)));
@@ -75,3 +77,5 @@ darwin_gt_pch_use_address (void *addr, size_t sz, int fd, size_t off)
 
   return ret;
 }
+
+const struct host_hooks host_hooks = HOST_HOOKS_INITIALIZER;