From 9c869d08d82c73f62ab3527567858ce4b0cf1257 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Zbigniew=20J=C4=99drzejewski-Szmek?= <zbyszek@in.waw.pl>
Date: Wed, 18 Jul 2018 17:26:17 +0200
Subject: [PATCH] meson: unify linux/stat.h check with other checks and use
 _GNU_SOURCE

Using _GNU_SOURCE is better because that's how we include the headers in the
actual build, and some headers define different stuff when it is defined.
sys/stat.h for example defines 'struct statx' conditionally.
---
 meson.build         | 20 ++++++++++++++------
 src/basic/missing.h |  2 +-
 2 files changed, 15 insertions(+), 7 deletions(-)

diff --git a/meson.build b/meson.build
index 68423bdfa..99035d230 100644
--- a/meson.build
+++ b/meson.build
@@ -421,11 +421,9 @@ decl_headers = '''
 #include <uchar.h>
 #include <linux/ethtool.h>
 #include <linux/fib_rules.h>
-#include <linux/stat.h>
 #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',
@@ -436,13 +434,23 @@ foreach decl : ['char16_t',
                ]
 
         # We get -1 if the size cannot be determined
-        have = cc.sizeof(decl, prefix : decl_headers) > 0
+        have = cc.sizeof(decl, prefix : decl_headers, args : '-D_GNU_SOURCE') > 0
+
+        if decl == 'struct statx'
+                if have
+                        want_linux_stat_h = false
+                else
+                        have = cc.sizeof(decl,
+                                         prefix : decl_headers + '#include <linux/stat.h>',
+                                         args : '-D_GNU_SOURCE') > 0
+                        want_linux_stat_h = have
+                endif
+        endif
+
         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)
+conf.set10('WANT_LINUX_STAT_H', want_linux_stat_h)
 
 foreach decl : [['IFLA_INET6_ADDR_GEN_MODE',         'linux/if_link.h'],
                 ['IN6_ADDR_GEN_MODE_STABLE_PRIVACY', 'linux/if_link.h'],
diff --git a/src/basic/missing.h b/src/basic/missing.h
index 14ad3d491..9044683b1 100644
--- a/src/basic/missing.h
+++ b/src/basic/missing.h
@@ -24,7 +24,7 @@
 #include <uchar.h>
 #include <unistd.h>
 
-#if !HAVE_STRUCT_STATX_IN_SYS_STAT_H
+#if WANT_LINUX_STAT_H
 #include <linux/stat.h>
 #endif
 
-- 
2.19.1