From e4693aa7c1777e6849b7bbb5fc9061e883bd58fd Mon Sep 17 00:00:00 2001
From: Roland McGrath <roland@hack.frob.com>
Date: Wed, 4 Mar 2015 13:52:45 -0800
Subject: Avoid C++ tests when the C++ cannot be linked.

---
 configure.ac | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

(limited to 'configure.ac')

diff --git a/configure.ac b/configure.ac
index 8043a27c3f..678c7399ad 100644
--- a/configure.ac
+++ b/configure.ac
@@ -50,9 +50,18 @@ if test $host != $build; then
 fi
 AC_SUBST(cross_compiling)
 AC_PROG_CPP
+AC_CHECK_TOOL(READELF, readelf, false)
+
 # We need the C++ compiler only for testing.
 AC_PROG_CXX
-AC_CHECK_TOOL(READELF, readelf, false)
+# It's useless to us if it can't link programs (e.g. missing -lstdc++).
+AC_CACHE_CHECK([whether $CXX can link programs], libc_cv_cxx_link_ok, [dnl
+AC_LANG_PUSH([C++])
+AC_LINK_IFELSE([AC_LANG_PROGRAM([], [])],
+	       [libc_cv_cxx_link_ok=yes],
+	       [libc_cv_cxx_link_ok=no])
+AC_LANG_POP([C++])])
+AS_IF([test $libc_cv_cxx_link_ok != yes], [CXX=])
 
 if test "`cd $srcdir; /bin/pwd`" = "`/bin/pwd`"; then
   AC_MSG_ERROR([you must configure in a separate build directory])
-- 
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