diff --git a/newlib/Makefile.in b/newlib/Makefile.in
index a662b4e78..05abe50e9 100644
--- a/newlib/Makefile.in
+++ b/newlib/Makefile.in
@@ -112,7 +112,7 @@ DIST_COMMON = $(srcdir)/Makefile.am $(top_srcdir)/configure \
 am__CONFIG_DISTCLEAN_FILES = config.status config.cache config.log \
  configure.lineno config.status.lineno
 mkinstalldirs = $(SHELL) $(top_srcdir)/../mkinstalldirs
-CONFIG_HEADER = _newlib_version.h newlib.h
+CONFIG_HEADER = newlib.h _newlib_version.h
 CONFIG_CLEAN_FILES =
 CONFIG_CLEAN_VPATH_FILES =
 am__vpath_adj_setup = srcdirstrip=`echo "$(srcdir)" | sed 's|.|.|g'`;
@@ -234,7 +234,7 @@ am__recursive_targets = \
 AM_RECURSIVE_TARGETS = $(am__recursive_targets:-recursive=) TAGS CTAGS \
 	cscope
 am__tagged_files = $(HEADERS) $(SOURCES) $(TAGS_FILES) \
-	$(LISP)_newlib_version.hin newlib.hin
+	$(LISP)newlib.hin _newlib_version.hin
 # Read a list of newline-separated strings from the standard input,
 # and print each of them once, without duplicates.  Input order is
 # *not* preserved.
@@ -548,7 +548,7 @@ MAKEOVERRIDES =
 # dejagnu support
 RUNTESTFLAGS = 
 @HAVE_DOC_TRUE@MKDOC = doc/makedoc$(EXEEXT_FOR_BUILD)
-all: _newlib_version.h newlib.h
+all: newlib.h _newlib_version.h
 	$(MAKE) $(AM_MAKEFLAGS) all-recursive
 
 .SUFFIXES:
@@ -588,28 +588,28 @@ $(ACLOCAL_M4): @MAINTAINER_MODE_TRUE@ $(am__aclocal_m4_deps)
 	$(am__cd) $(srcdir) && $(ACLOCAL) $(ACLOCAL_AMFLAGS)
 $(am__aclocal_m4_deps):
 
-_newlib_version.h: stamp-h1
+newlib.h: stamp-h1
 	@test -f $@ || rm -f stamp-h1
 	@test -f $@ || $(MAKE) $(AM_MAKEFLAGS) stamp-h1
 
-stamp-h1: $(srcdir)/_newlib_version.hin $(top_builddir)/config.status
+stamp-h1: $(srcdir)/newlib.hin $(top_builddir)/config.status
 	@rm -f stamp-h1
-	cd $(top_builddir) && $(SHELL) ./config.status _newlib_version.h
-$(srcdir)/_newlib_version.hin: @MAINTAINER_MODE_TRUE@ $(am__configure_deps) 
+	cd $(top_builddir) && $(SHELL) ./config.status newlib.h
+$(srcdir)/newlib.hin: @MAINTAINER_MODE_TRUE@ $(am__configure_deps) 
 	($(am__cd) $(top_srcdir) && $(AUTOHEADER))
 	rm -f stamp-h1
 	touch $@
 
-newlib.h: stamp-h2
+_newlib_version.h: stamp-h2
 	@test -f $@ || rm -f stamp-h2
 	@test -f $@ || $(MAKE) $(AM_MAKEFLAGS) stamp-h2
 
-stamp-h2: $(srcdir)/newlib.hin $(top_builddir)/config.status
+stamp-h2: $(srcdir)/_newlib_version.hin $(top_builddir)/config.status
 	@rm -f stamp-h2
-	cd $(top_builddir) && $(SHELL) ./config.status newlib.h
+	cd $(top_builddir) && $(SHELL) ./config.status _newlib_version.h
 
 distclean-hdr:
-	-rm -f _newlib_version.h stamp-h1 newlib.h stamp-h2
+	-rm -f newlib.h stamp-h1 _newlib_version.h stamp-h2
 install-toollibLIBRARIES: $(toollib_LIBRARIES)
 	@$(NORMAL_INSTALL)
 	@list='$(toollib_LIBRARIES)'; test -n "$(toollibdir)" || list=; \
@@ -852,8 +852,8 @@ distclean-DEJAGNU:
 check-am: all-am
 	$(MAKE) $(AM_MAKEFLAGS) check-DEJAGNU
 check: check-recursive
-all-am: Makefile $(LIBRARIES) $(LTLIBRARIES) $(DATA) _newlib_version.h \
-		newlib.h
+all-am: Makefile $(LIBRARIES) $(LTLIBRARIES) $(DATA) newlib.h \
+		_newlib_version.h
 installdirs: installdirs-recursive
 installdirs-am:
 	for dir in "$(DESTDIR)$(toollibdir)" "$(DESTDIR)$(toollibdir)" "$(DESTDIR)$(toollibdir)"; do \
diff --git a/newlib/configure b/newlib/configure
index 5a0993c85..879392da8 100755
--- a/newlib/configure
+++ b/newlib/configure
@@ -2251,7 +2251,13 @@ ac_compiler_gnu=$ac_cv_c_compiler_gnu
 
 
 
-ac_config_headers="$ac_config_headers _newlib_version.h:_newlib_version.hin newlib.h:newlib.hin"
+
+ac_config_headers="$ac_config_headers newlib.h:newlib.hin"
+
+
+
+
+ac_config_headers="$ac_config_headers _newlib_version.h:_newlib_version.hin"
 
 
 ac_aux_dir=
@@ -11974,7 +11980,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11977 "configure"
+#line 11983 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -12080,7 +12086,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 12083 "configure"
+#line 12089 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -14451,8 +14457,8 @@ cat >>$CONFIG_STATUS <<\_ACEOF || ac_write_fail=1
 for ac_config_target in $ac_config_targets
 do
   case $ac_config_target in
-    "_newlib_version.h") CONFIG_HEADERS="$CONFIG_HEADERS _newlib_version.h:_newlib_version.hin" ;;
     "newlib.h") CONFIG_HEADERS="$CONFIG_HEADERS newlib.h:newlib.hin" ;;
+    "_newlib_version.h") CONFIG_HEADERS="$CONFIG_HEADERS _newlib_version.h:_newlib_version.hin" ;;
     "depfiles") CONFIG_COMMANDS="$CONFIG_COMMANDS depfiles" ;;
     "libtool") CONFIG_COMMANDS="$CONFIG_COMMANDS libtool" ;;
     "Makefile") CONFIG_FILES="$CONFIG_FILES Makefile" ;;
@@ -15051,6 +15057,7 @@ $as_echo "$as_me: executing $ac_file commands" >&6;}
 
 
   case $ac_file$ac_mode in
+    "newlib.h":H) sed -i.tmp -e '/^#define [^_]/d' -e '/^\/\* #undef [^_]/d' newlib.h && rm -f newlib.h.tmp ;;
     "depfiles":C) test x"$AMDEP_TRUE" != x"" || {
   # Older Autoconf quotes --file arguments for eval, but not when files
   # are listed without --file.  Let's play safe and only enable the eval
diff --git a/newlib/configure.ac b/newlib/configure.ac
index d95000db9..b4d11f5e3 100644
--- a/newlib/configure.ac
+++ b/newlib/configure.ac
@@ -3,7 +3,23 @@ dnl Process this file with autoconf to produce a configure script.
 
 AC_INIT([newlib],[NEWLIB_VERSION])
 AC_CONFIG_SRCDIR([libc])
-AC_CONFIG_HEADERS([_newlib_version.h:_newlib_version.hin newlib.h:newlib.hin])
+
+dnl Since we can't control what defines autoheader picks up (various autoconf
+dnl macros will add their own), filter out all the ones w/out a _ prefix.  All
+dnl the ones we want to export use a _ prefix, and all the rest we don't want
+dnl to export as it'll pollute the namespace of newlib users.
+dnl NB: newlib.h must be the first AC_CONFIG_HEADERS call for autoheader.
+AC_CONFIG_HEADERS([newlib.h:newlib.hin], [sed -i.tmp -e '/^#define [^_]/d' -e '/^\/\* #undef [^_]/d' newlib.h && rm -f newlib.h.tmp])
+AH_TOP([/* NB: The contents are filtered before being installed. */
+
+#ifndef __NEWLIB_H__
+#define __NEWLIB_H__ 1
+
+/* Newlib version */
+#include <_newlib_version.h>])
+AH_BOTTOM([#endif /* !__NEWLIB_H__ */])
+
+AC_CONFIG_HEADERS([_newlib_version.h:_newlib_version.hin])
 
 dnl Can't be done in NEWLIB_CONFIGURE because that confuses automake. 
 AC_CONFIG_AUX_DIR(..)
diff --git a/newlib/newlib.hin b/newlib/newlib.hin
index 15543f403..69a7cb7a7 100644
--- a/newlib/newlib.hin
+++ b/newlib/newlib.hin
@@ -1,13 +1,68 @@
-/* newlib.hin.  Manually edited from the output of autoheader to
-   remove all PACKAGE_ macros which will collide with any user
-   package using newlib header files and having its own package name,
-   version, etc...  */
+/* newlib.hin.  Generated from configure.ac by autoheader.  */
+
+/* NB: The contents are filtered before being installed. */
+
 #ifndef __NEWLIB_H__
 #define __NEWLIB_H__ 1
 
 /* Newlib version */
 #include <_newlib_version.h>
 
+/* Define to 1 if you have the <dlfcn.h> header file. */
+#undef HAVE_DLFCN_H
+
+/* Define to 1 if you have the <inttypes.h> header file. */
+#undef HAVE_INTTYPES_H
+
+/* Define to 1 if you have the <memory.h> header file. */
+#undef HAVE_MEMORY_H
+
+/* Define to 1 if you have the <stdint.h> header file. */
+#undef HAVE_STDINT_H
+
+/* Define to 1 if you have the <stdlib.h> header file. */
+#undef HAVE_STDLIB_H
+
+/* Define to 1 if you have the <strings.h> header file. */
+#undef HAVE_STRINGS_H
+
+/* Define to 1 if you have the <string.h> header file. */
+#undef HAVE_STRING_H
+
+/* Define to 1 if you have the <sys/stat.h> header file. */
+#undef HAVE_SYS_STAT_H
+
+/* Define to 1 if you have the <sys/types.h> header file. */
+#undef HAVE_SYS_TYPES_H
+
+/* Define to 1 if you have the <unistd.h> header file. */
+#undef HAVE_UNISTD_H
+
+/* Define to the sub-directory in which libtool stores uninstalled libraries.
+   */
+#undef LT_OBJDIR
+
+/* Define to the address where bug reports for this package should be sent. */
+#undef PACKAGE_BUGREPORT
+
+/* Define to the full name of this package. */
+#undef PACKAGE_NAME
+
+/* Define to the full name and version of this package. */
+#undef PACKAGE_STRING
+
+/* Define to the one symbol short name of this package. */
+#undef PACKAGE_TARNAME
+
+/* Define to the home page for this package. */
+#undef PACKAGE_URL
+
+/* Define to the version of this package. */
+#undef PACKAGE_VERSION
+
+/* Define to 1 if you have the ANSI C header files. */
+#undef STDC_HEADERS
+
 /* If atexit() may dynamically allocate space for cleanup functions. */
 #undef _ATEXIT_DYNAMIC_ALLOC