diff --git a/Xi/exevents.c b/Xi/exevents.c
index 7000454f87..8e1b8880ed 100644
--- a/Xi/exevents.c
+++ b/Xi/exevents.c
@@ -82,6 +82,7 @@ SOFTWARE.
 
 #include "dix/cursor_priv.h"
 #include "os/bug_priv.h"
+#include "os/osdep.h"
 
 #include <X11/X.h>
 #include <X11/Xproto.h>
diff --git a/hw/xfree86/common/xf86AutoConfig.c b/hw/xfree86/common/xf86AutoConfig.c
index 24d37ba703..4178215871 100644
--- a/hw/xfree86/common/xf86AutoConfig.c
+++ b/hw/xfree86/common/xf86AutoConfig.c
@@ -33,6 +33,8 @@
 #include <xorg-config.h>
 #endif
 
+#include "os/osdep.h"
+
 #include "xf86.h"
 #include "xf86Parser_priv.h"
 #include "xf86tokens.h"
diff --git a/hw/xfree86/common/xf86Bus.c b/hw/xfree86/common/xf86Bus.c
index 7d874eb4b1..0c9dc5c2f4 100644
--- a/hw/xfree86/common/xf86Bus.c
+++ b/hw/xfree86/common/xf86Bus.c
@@ -39,6 +39,7 @@
 #include <X11/X.h>
 
 #include "config/hotplug_priv.h"
+#include "os/osdep.h"
 
 #include "os.h"
 #include "xf86_priv.h"
diff --git a/hw/xfree86/common/xf86Helper.c b/hw/xfree86/common/xf86Helper.c
index 7b193a9412..7a654fcf40 100644
--- a/hw/xfree86/common/xf86Helper.c
+++ b/hw/xfree86/common/xf86Helper.c
@@ -45,6 +45,7 @@
 #include "dix/input_priv.h"
 #include "mi/mi_priv.h"
 #include "os/log_priv.h"
+#include "os/osdep.h"
 
 #include "os.h"
 #include "servermd.h"
diff --git a/hw/xfree86/common/xf86pciBus.c b/hw/xfree86/common/xf86pciBus.c
index 7c8913bdd4..0d3a04673f 100644
--- a/hw/xfree86/common/xf86pciBus.c
+++ b/hw/xfree86/common/xf86pciBus.c
@@ -39,6 +39,7 @@
 #include <X11/X.h>
 
 #include "os/log_priv.h"
+#include "os/osdep.h"
 
 #include "os.h"
 #include "Pci.h"
diff --git a/hw/xfree86/common/xf86platformBus.c b/hw/xfree86/common/xf86platformBus.c
index 7a97986ddd..19588d76c6 100644
--- a/hw/xfree86/common/xf86platformBus.c
+++ b/hw/xfree86/common/xf86platformBus.c
@@ -40,6 +40,7 @@
 #include "config/hotplug_priv.h"
 #include "dix/screenint_priv.h"
 #include "randr/randrstr_priv.h"
+#include "os/osdep.h"
 
 #include "os.h"
 #include "../os-support/linux/systemd-logind.h"
diff --git a/hw/xfree86/i2c/xf86i2c.c b/hw/xfree86/i2c/xf86i2c.c
index c70aaf1ac4..1668278bed 100644
--- a/hw/xfree86/i2c/xf86i2c.c
+++ b/hw/xfree86/i2c/xf86i2c.c
@@ -13,6 +13,8 @@
 #include <sys/time.h>
 #include <string.h>
 
+#include "os/osdep.h"
+
 #include "misc.h"
 #include "xf86.h"
 #include "xf86_OSproc.h"
diff --git a/include/os.h b/include/os.h
index da6b3d6fe7..675d5335d4 100644
--- a/include/os.h
+++ b/include/os.h
@@ -166,13 +166,6 @@ XNFcallocarray(size_t nmemb, size_t size) __attribute__((returns_nonnull));
 extern _X_EXPORT void *
 XNFrealloc(void * /*ptr */ , unsigned long /*amount */ );
 
-/*
- * This function reallocarray(3)s passed buffer, terminating the server if
- * there is not enough memory or the arguments overflow when multiplied.
- */
-extern _X_EXPORT void *
-XNFreallocarray(void *ptr, size_t nmemb, size_t size);
-
 /*
  * This function strdup(3)s passed string. The only difference from the library
  * function that it is safe to pass NULL, as NULL will be returned.
diff --git a/os/alloc.c b/os/alloc.c
index 5049957f12..0a00c6386e 100644
--- a/os/alloc.c
+++ b/os/alloc.c
@@ -7,7 +7,8 @@
 
 #include <stdlib.h>
 
-#include "os.h"
+#include "include/os.h"
+#include "os/osdep.h"
 
 void *
 XNFalloc(unsigned long amount)
diff --git a/os/osdep.h b/os/osdep.h
index c8c733aa52..b30743a304 100644
--- a/os/osdep.h
+++ b/os/osdep.h
@@ -203,6 +203,12 @@ extern Bool CoreDump;
 extern Bool NoListenAll;
 extern Bool AllowByteSwappedClients;
 
+/*
+ * This function reallocarray(3)s passed buffer, terminating the server if
+ * there is not enough memory or the arguments overflow when multiplied.
+ */
+void *XNFreallocarray(void *ptr, size_t nmemb, size_t size);
+
 #if __has_builtin(__builtin_popcountl)
 # define Ones __builtin_popcountl
 #else