From f4f5e50a0ab828991ff54e7013acc6917a9510fa Mon Sep 17 00:00:00 2001
From: Andrew Jeddeloh <andrewjeddeloh@gmail.com>
Date: Tue, 14 Jun 2016 02:09:06 -0700
Subject: [PATCH] build: fix missing symbol for old kernel headers (#3530)

Fix issue where IN6_ADDR_GEN_MODE_STABLE_PRIVACY is undefined but
IFLA_INET6_ADDR_GEN_MODE is defined and thus the former does not get
fixed in missing.h. This occurs with kernel headers new enough to have
the IFLA_INET6_ADDR_GEN_MODE but old enough to not yet have
IN6_ADDR_GEN_MODE_STABLE_PRIVACY (e.g. 3.18).
---
 configure.ac        | 1 +
 src/basic/missing.h | 3 +++
 2 files changed, 4 insertions(+)

diff --git a/configure.ac b/configure.ac
index 329861a291..ffc6eedcdd 100644
--- a/configure.ac
+++ b/configure.ac
@@ -324,6 +324,7 @@ AC_CHECK_TYPES([char16_t, char32_t, key_serial_t],
 ]])
 
 AC_CHECK_DECLS([IFLA_INET6_ADDR_GEN_MODE,
+                IN6_ADDR_GEN_MODE_STABLE_PRIVACY,
                 IFLA_MACVLAN_FLAGS,
                 IFLA_IPVLAN_MODE,
                 IFLA_VTI_REMOTE,
diff --git a/src/basic/missing.h b/src/basic/missing.h
index 8b977871e9..53dfa1c801 100644
--- a/src/basic/missing.h
+++ b/src/basic/missing.h
@@ -577,6 +577,9 @@ struct btrfs_ioctl_quota_ctl_args {
 
 #define IN6_ADDR_GEN_MODE_EUI64 0
 #define IN6_ADDR_GEN_MODE_NONE 1
+#endif
+
+#if !HAVE_DECL_IN6_ADDR_GEN_MODE_STABLE_PRIVACY
 #define IN6_ADDR_GEN_MODE_STABLE_PRIVACY 2
 #endif