add sys/mman.h for MAP_ANON and MAP_ANONYMOUS

include/Makefile.am

@@ -6,6 +6,7 @@ noinst_HEADERS += sys/queue.h
 noinst_HEADERS += sys/socket.h
 noinst_HEADERS += sys/types.h
 noinst_HEADERS += sys/time.h
+noinst_HEADERS += sys/mman.h
 noinst_HEADERS += err.h
 noinst_HEADERS += ifaddrs.h
 noinst_HEADERS += imsg.h

include/sys/mman.h

@@ -0,0 +1,19 @@
+/*
+ * Public domain
+ * sys/mman.h compatibility shim
+ */
+
+#include_next <sys/mman.h>
+
+#ifndef LIBCRYPTOCOMPAT_MMAN_H
+#define LIBCRYPTOCOMPAT_MMAN_H
+
+#ifndef MAP_ANON
+#ifdef MAP_ANONYMOUS
+#define MAP_ANON MAP_ANONYMOUS
+#else
+#error "System does not support mapping anonymous pages?"
+#endif
+#endif
+
+#endif