From 79df4db3fd122f5040bdf2225c3047375de3b0d2 Mon Sep 17 00:00:00 2001
From: Filipe Brandenburger <filbranden@google.com>
Date: Sun, 15 Jul 2018 22:43:35 -0700
Subject: [PATCH] build-sys: Detect whether struct statx is defined in
 sys/stat.h
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Starting with glibc 2.27.9000-36.fc29, include file sys/stat.h will have a
definition for struct statx, in which case include file linux/stat.h should be
avoided, in order to prevent a duplicate definition.

    In file included from ../src/basic/missing.h:18,
		     from ../src/basic/util.h:28,
		     from ../src/basic/hashmap.h:10,
		     from ../src/shared/bus-util.h:12,
		     from ../src/libsystemd/sd-bus/bus-creds.c:11:
    /usr/include/linux/stat.h:99:8: error: redefinition of ‘struct statx’
     struct statx {
	    ^~~~~
    In file included from /usr/include/sys/stat.h:446,
		     from ../src/basic/util.h:19,
		     from ../src/basic/hashmap.h:10,
		     from ../src/shared/bus-util.h:12,
		     from ../src/libsystemd/sd-bus/bus-creds.c:11:
    /usr/include/bits/statx.h:36:8: note: originally defined here
     struct statx
	    ^~~~~

Extend our meson.build to look for struct statx when only sys/stat.h is
included and, in that case, do not include linux/stat.h anymore.

Tested that systemd builds correctly when using a glibc version that includes a
definition for struct statx.

glibc Fedora RPM update:
https://src.fedoraproject.org/rpms/glibc/c/28cb5d31fc1e5887912283c889689c47076278ae

glibc upstream commit:
https://sourceware.org/git/?p=glibc.git;a=commitdiff;h=fd70af45528d59a00eb3190ef6706cb299488fcd
---
 meson.build            | 5 +++++
 src/basic/missing.h    | 5 ++++-
 src/basic/xattr-util.c | 1 -
 3 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/meson.build b/meson.build
index 04331dd41..a0e724070 100644
--- a/meson.build
+++ b/meson.build
@@ -425,6 +425,7 @@ decl_headers = '''
 #include <sys/stat.h>
 '''
 # FIXME: key_serial_t is only defined in keyutils.h, this is bound to fail
+# FIXME: these should use -D_GNU_SOURCE, since that is defined at build time
 
 foreach decl : ['char16_t',
                 'char32_t',
@@ -439,6 +440,10 @@ foreach decl : ['char16_t',
         conf.set10('HAVE_' + decl.underscorify().to_upper(), have)
 endforeach
 
+conf.set10('HAVE_STRUCT_STATX_IN_SYS_STAT_H', cc.sizeof('struct statx', prefix : '''
+#include <sys/stat.h>
+''', args : '-D_GNU_SOURCE') > 0)
+
 foreach decl : [['IFLA_INET6_ADDR_GEN_MODE',         'linux/if_link.h'],
                 ['IN6_ADDR_GEN_MODE_STABLE_PRIVACY', 'linux/if_link.h'],
                 ['IFLA_VRF_TABLE',                   'linux/if_link.h'],
diff --git a/src/basic/missing.h b/src/basic/missing.h
index 71a07d057..14ad3d491 100644
--- a/src/basic/missing.h
+++ b/src/basic/missing.h
@@ -15,7 +15,6 @@
 #include <linux/neighbour.h>
 #include <linux/oom.h>
 #include <linux/rtnetlink.h>
-#include <linux/stat.h>
 #include <net/ethernet.h>
 #include <stdlib.h>
 #include <sys/resource.h>
@@ -25,6 +24,10 @@
 #include <uchar.h>
 #include <unistd.h>
 
+#if !HAVE_STRUCT_STATX_IN_SYS_STAT_H
+#include <linux/stat.h>
+#endif
+
 #if HAVE_AUDIT
 #include <libaudit.h>
 #endif
diff --git a/src/basic/xattr-util.c b/src/basic/xattr-util.c
index c5c55ea84..0ee097983 100644
--- a/src/basic/xattr-util.c
+++ b/src/basic/xattr-util.c
@@ -2,7 +2,6 @@
 
 #include <errno.h>
 #include <fcntl.h>
-#include <linux/stat.h>
 #include <stdint.h>
 #include <stdlib.h>
 #include <string.h>