From 79afb676904653403145fda9e1a6a9d3ea1cb22a Mon Sep 17 00:00:00 2001
From: Jussi Kukkonen <jussi.kukkonen@intel.com>
Date: Fri, 7 Aug 2015 11:10:32 +0300
Subject: [PATCH 4/4] Avoid mis-identifying systems as SVR4

Linux can be misdetected as SVR4 because it has
libelf installed. This leads to linking with libelf, even though no
symbols from that library were actually used, and to a workaround for
a buggy getlogin() being enabled.

It is not documented which exact SVR4 system had the bug that the
workaround was added for, so all I could do is make an educated guess
at the #defines its compiler would be likely to set.

Modified from patch by Maarten ter Huurne.

Upstream-Status: Submitted [http://savannah.gnu.org/bugs/?43223]

Signed-off-by: Jussi Kukkonen <jussi.kukkonen@intel.com>
---
 configure.ac | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/configure.ac b/configure.ac
index dc928ae..65439ce 100644
--- a/configure.ac
+++ b/configure.ac
@@ -179,14 +179,24 @@ AC_EGREP_CPP(yes,
 #endif
 ], LIBS="$LIBS -lsocket -linet";seqptx=1)
 
+AC_CHECKING(SVR4)
+AC_EGREP_CPP(yes,
+[main () {
+#if defined(SVR4) || defined(__SVR4)
+  yes;
+#endif
+], AC_NOTE(- you have a SVR4 system) AC_DEFINE(SVR4) svr4=1)
+if test -n "$svr4" ; then
 oldlibs="$LIBS"
 LIBS="$LIBS -lelf"
 AC_CHECKING(SVR4)
 AC_TRY_LINK([#include <utmpx.h>
 ],,
-[AC_CHECK_HEADER(dwarf.h, AC_DEFINE(SVR4) AC_DEFINE(BUGGYGETLOGIN),
-[AC_CHECK_HEADER(elf.h, AC_DEFINE(SVR4) AC_DEFINE(BUGGYGETLOGIN))])]
+[AC_CHECK_HEADER(dwarf.h, AC_DEFINE(BUGGYGETLOGIN),
+[AC_CHECK_HEADER(elf.h, AC_DEFINE(BUGGYGETLOGIN))])]
 ,LIBS="$oldlibs")
+fi
+
 AC_CHECK_HEADERS([stropts.h string.h strings.h])
 
 AC_CHECKING(for Solaris 2.x)
-- 
2.1.4