diff --git a/config/ChangeLog b/config/ChangeLog
index 87af62b4e..83eab40cc 100644
--- a/config/ChangeLog
+++ b/config/ChangeLog
@@ -1,3 +1,10 @@
+2010-12-06  Dave Korn  <dave.korn.cygwin@gmail.com>
+
+	PR target/40125
+	PR lto/46695
+	* lthostflags.m4: New file.
+	(ACX_LT_HOST_FLAGS): Define.
+
 2010-12-02  Dave Korn  <dave.korn.cygwin@gmail.com>
 
 	* mh-cygwin (LDFLAGS): Turn up stack allocation to 12MB.
diff --git a/config/lthostflags.m4 b/config/lthostflags.m4
new file mode 100644
index 000000000..bc0f59ee7
--- /dev/null
+++ b/config/lthostflags.m4
@@ -0,0 +1,33 @@
+dnl Copyright (C) 2010 Free Software Foundation, Inc.
+dnl This file is free software, distributed under the terms of the GNU
+dnl General Public License.  As a special exception to the GNU General
+dnl Public License, this file may be distributed as part of a program
+dnl that contains a configuration script generated by Autoconf, under
+dnl the same distribution terms as the rest of that program.
+
+dnl usage: ACX_LT_HOST_FLAGS([default_flags])
+dnl Defines and AC_SUBSTs lt_host_flags
+
+
+AC_DEFUN([ACX_LT_HOST_FLAGS], [
+AC_REQUIRE([AC_CANONICAL_SYSTEM])
+
+case $host in
+  *-cygwin* | *-mingw*)
+    # 'host' will be top-level target in the case of a target lib,
+    # we must compare to with_cross_host to decide if this is a native
+    # or cross-compiler and select where to install dlls appropriately.
+    if test -n "$with_cross_host" &&
+	test x"$with_cross_host" != x"no"; then
+      lt_host_flags='-no-undefined -bindir "$(toolexeclibdir)"';
+    else
+      lt_host_flags='-no-undefined -bindir "$(bindir)"';
+    fi
+    ;;
+  *)
+    lt_host_flags=[$1]
+    ;;
+esac
+
+AC_SUBST(lt_host_flags)
+])