commit d94c614feec525860ae3640727a740fb5a0fe9b0
Author: Jason Merrill <jason@redhat.com>
Date:   Thu Sep 22 09:01:16 2016 -0400

            * configure.ac: Define HAVE_MEMALIGN for newlib.

diff --git a/libstdc++-v3/configure b/libstdc++-v3/configure
index 6332c4d..973d6d1 100755
--- a/libstdc++-v3/configure
+++ b/libstdc++-v3/configure
@@ -28822,6 +28822,8 @@ else
 
     $as_echo "#define HAVE_ICONV 1" >>confdefs.h
 
+    $as_echo "#define HAVE_MEMALIGN 1" >>confdefs.h
+
   else
 
 # Base decisions on target environment.
diff --git a/libstdc++-v3/configure.ac b/libstdc++-v3/configure.ac
index 5657ecb..baf605c 100644
--- a/libstdc++-v3/configure.ac
+++ b/libstdc++-v3/configure.ac
@@ -324,6 +324,7 @@ else
     AC_DEFINE(HAVE_TANHF)
 
     AC_DEFINE(HAVE_ICONV)
+    AC_DEFINE(HAVE_MEMALIGN)
   else
     GLIBCXX_CROSSCONFIG
   fi