From 0f7010b10c20a84c90222925d39e222dc5d998a1 Mon Sep 17 00:00:00 2001
From: Lennart Poettering <lennart@poettering.net>
Date: Mon, 25 Dec 2017 12:07:40 +0100
Subject: [PATCH] meson: when pivot_root() is added one day, look for it in
 <unistd.h>

We of course don't know in which header glibc will export pivot_root()
and if it ever will. But there's a good chance they'll place it where
chroot() is located, given the similarity in the operations, hence let's
try our luck and look for it at the same place.

If we are lucky this means we don't have to patch our code if glibc
decides to expose the call one day.
---
 meson.build | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/meson.build b/meson.build
index aea61990c..ac61dbc93 100644
--- a/meson.build
+++ b/meson.build
@@ -520,7 +520,8 @@ endforeach
 foreach ident : [
         ['memfd_create',      '''#include <sys/mman.h>'''],
         ['gettid',            '''#include <sys/types.h>'''],
-        ['pivot_root',        '''#include <stdlib.h>'''],     # no known header declares pivot_root
+        ['pivot_root',        '''#include <stdlib.h>
+//                                 #include <unistd.h>'''],     # no known header declares pivot_root
         ['name_to_handle_at', '''#include <sys/types.h>
                                  #include <sys/stat.h>
                                  #include <fcntl.h>'''],
-- 
2.30.2