diff --git a/Makefile.am b/Makefile.am
index e6c9adb5e..b5b0789e8 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -36,6 +36,10 @@ libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES = png.c pngerror.c\
 	pngset.c pngtrans.c pngwio.c pngwrite.c pngwtran.c pngwutil.c\
 	png.h pngconf.h pngdebug.h pnginfo.h pngpriv.h pngstruct.h
 
+if PNG_ARM_NEON
+libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES += arm/filter_neon.S
+endif
+
 nodist_libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES = pnglibconf.h
 
 libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_CPPFLAGS = @LIBPNG_DEFINES@
diff --git a/Makefile.in b/Makefile.in
index 742320ed9..093b87917 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -41,12 +41,13 @@ POST_UNINSTALL = :
 build_triplet = @build@
 host_triplet = @host@
 check_PROGRAMS = pngtest$(EXEEXT) pngvalid$(EXEEXT)
+@PNG_ARM_NEON_TRUE@am__append_1 = arm/filter_neon.S
 
 #   Versioned symbols and restricted exports
-@HAVE_LD_VERSION_SCRIPT_TRUE@@HAVE_SOLARIS_LD_TRUE@am__append_1 = -Wl,-M -Wl,libpng.vers
-@HAVE_LD_VERSION_SCRIPT_TRUE@@HAVE_SOLARIS_LD_FALSE@am__append_2 = -Wl,--version-script=libpng.vers
+@HAVE_LD_VERSION_SCRIPT_TRUE@@HAVE_SOLARIS_LD_TRUE@am__append_2 = -Wl,-M -Wl,libpng.vers
+@HAVE_LD_VERSION_SCRIPT_TRUE@@HAVE_SOLARIS_LD_FALSE@am__append_3 = -Wl,--version-script=libpng.vers
 #   Only restricted exports when possible
-@HAVE_LD_VERSION_SCRIPT_FALSE@am__append_3 = -export-symbols libpng.sym
+@HAVE_LD_VERSION_SCRIPT_FALSE@am__append_4 = -export-symbols libpng.sym
 subdir = .
 DIST_COMMON = README $(am__configure_deps) $(dist_man_MANS) \
 	$(pkginclude_HEADERS) $(srcdir)/Makefile.am \
@@ -91,6 +92,12 @@ am__installdirs = "$(DESTDIR)$(libdir)" "$(DESTDIR)$(bindir)" \
 	"$(DESTDIR)$(pkgincludedir)"
 LTLIBRARIES = $(lib_LTLIBRARIES)
 libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_LIBADD =
+am__libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES_DIST = png.c \
+	pngerror.c pngget.c pngmem.c pngpread.c pngread.c pngrio.c \
+	pngrtran.c pngrutil.c pngset.c pngtrans.c pngwio.c pngwrite.c \
+	pngwtran.c pngwutil.c png.h pngconf.h pngdebug.h pnginfo.h \
+	pngpriv.h pngstruct.h arm/filter_neon.S
+@PNG_ARM_NEON_TRUE@am__objects_1 = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la-filter_neon.lo
 am_libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_OBJECTS =  \
 	libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la-png.lo \
 	libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la-pngerror.lo \
@@ -106,7 +113,8 @@ am_libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_OBJECTS =  \
 	libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la-pngwio.lo \
 	libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la-pngwrite.lo \
 	libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la-pngwtran.lo \
-	libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la-pngwutil.lo
+	libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la-pngwutil.lo \
+	$(am__objects_1)
 nodist_libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_OBJECTS =
 libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_OBJECTS =  \
 	$(am_libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_OBJECTS) \
@@ -127,6 +135,11 @@ DEFAULT_INCLUDES = -I.@am__isrc@
 depcomp = $(SHELL) $(top_srcdir)/depcomp
 am__depfiles_maybe = depfiles
 am__mv = mv -f
+CPPASCOMPILE = $(CCAS) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) \
+	$(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CCASFLAGS) $(CCASFLAGS)
+LTCPPASCOMPILE = $(LIBTOOL) $(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) \
+	--mode=compile $(CCAS) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) \
+	$(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CCASFLAGS) $(CCASFLAGS)
 COMPILE = $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) \
 	$(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS)
 LTCOMPILE = $(LIBTOOL) --tag=CC $(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) \
@@ -139,7 +152,8 @@ LINK = $(LIBTOOL) --tag=CC $(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) \
 SOURCES = $(libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES) \
 	$(nodist_libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES) \
 	$(pngtest_SOURCES) $(pngvalid_SOURCES)
-DIST_SOURCES = $(libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES) \
+DIST_SOURCES =  \
+	$(am__libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES_DIST) \
 	$(pngtest_SOURCES) $(pngvalid_SOURCES)
 man3dir = $(mandir)/man3
 man5dir = $(mandir)/man5
@@ -174,6 +188,9 @@ AUTOHEADER = @AUTOHEADER@
 AUTOMAKE = @AUTOMAKE@
 AWK = @AWK@
 CC = @CC@
+CCAS = @CCAS@
+CCASDEPMODE = @CCASDEPMODE@
+CCASFLAGS = @CCASFLAGS@
 CCDEPMODE = @CCDEPMODE@
 CFLAGS = @CFLAGS@
 CPP = @CPP@
@@ -324,17 +341,17 @@ bin_SCRIPTS = @binconfigs@
 # rules to build libpng, only build the old library on request
 lib_LTLIBRARIES = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
 # EXTRA_LTLIBRARIES= libpng.la
-libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES = png.c pngerror.c\
-	pngget.c pngmem.c pngpread.c pngread.c pngrio.c pngrtran.c pngrutil.c\
-	pngset.c pngtrans.c pngwio.c pngwrite.c pngwtran.c pngwutil.c\
-	png.h pngconf.h pngdebug.h pnginfo.h pngpriv.h pngstruct.h
-
+libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES = png.c pngerror.c \
+	pngget.c pngmem.c pngpread.c pngread.c pngrio.c pngrtran.c \
+	pngrutil.c pngset.c pngtrans.c pngwio.c pngwrite.c pngwtran.c \
+	pngwutil.c png.h pngconf.h pngdebug.h pnginfo.h pngpriv.h \
+	pngstruct.h $(am__append_1)
 nodist_libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES = pnglibconf.h
 libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_CPPFLAGS = @LIBPNG_DEFINES@
 libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_LDFLAGS = -no-undefined \
 	-export-dynamic -version-number \
 	@PNGLIB_MAJOR@@PNGLIB_MINOR@:@PNGLIB_RELEASE@:0 \
-	$(am__append_1) $(am__append_2) $(am__append_3)
+	$(am__append_2) $(am__append_3) $(am__append_4)
 @HAVE_LD_VERSION_SCRIPT_FALSE@libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_DEPENDENCIES = libpng.sym
 @HAVE_LD_VERSION_SCRIPT_TRUE@libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_DEPENDENCIES = libpng.vers
 pkginclude_HEADERS = png.h pngconf.h
@@ -372,7 +389,7 @@ all: config.h
 	$(MAKE) $(AM_MAKEFLAGS) all-am
 
 .SUFFIXES:
-.SUFFIXES: .chk .dfn .out .c .lo .o .obj
+.SUFFIXES: .chk .dfn .out .S .c .lo .o .obj
 am--refresh:
 	@:
 $(srcdir)/Makefile.in: @MAINTAINER_MODE_TRUE@ $(srcdir)/Makefile.am  $(am__configure_deps)
@@ -517,6 +534,7 @@ mostlyclean-compile:
 distclean-compile:
 	-rm -f *.tab.c
 
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la-filter_neon.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la-png.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la-pngerror.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la-pngget.Plo@am__quote@
@@ -535,6 +553,34 @@ distclean-compile:
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/pngtest.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/pngvalid.Po@am__quote@
 
+.S.o:
+@am__fastdepCCAS_TRUE@	$(CPPASCOMPILE) -MT $@ -MD -MP -MF $(DEPDIR)/$*.Tpo -c -o $@ $<
+@am__fastdepCCAS_TRUE@	$(am__mv) $(DEPDIR)/$*.Tpo $(DEPDIR)/$*.Po
+@AMDEP_TRUE@@am__fastdepCCAS_FALSE@	source='$<' object='$@' libtool=no @AMDEPBACKSLASH@
+@AMDEP_TRUE@@am__fastdepCCAS_FALSE@	DEPDIR=$(DEPDIR) $(CCASDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+@am__fastdepCCAS_FALSE@	$(CPPASCOMPILE) -c -o $@ $<
+
+.S.obj:
+@am__fastdepCCAS_TRUE@	$(CPPASCOMPILE) -MT $@ -MD -MP -MF $(DEPDIR)/$*.Tpo -c -o $@ `$(CYGPATH_W) '$<'`
+@am__fastdepCCAS_TRUE@	$(am__mv) $(DEPDIR)/$*.Tpo $(DEPDIR)/$*.Po
+@AMDEP_TRUE@@am__fastdepCCAS_FALSE@	source='$<' object='$@' libtool=no @AMDEPBACKSLASH@
+@AMDEP_TRUE@@am__fastdepCCAS_FALSE@	DEPDIR=$(DEPDIR) $(CCASDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+@am__fastdepCCAS_FALSE@	$(CPPASCOMPILE) -c -o $@ `$(CYGPATH_W) '$<'`
+
+.S.lo:
+@am__fastdepCCAS_TRUE@	$(LTCPPASCOMPILE) -MT $@ -MD -MP -MF $(DEPDIR)/$*.Tpo -c -o $@ $<
+@am__fastdepCCAS_TRUE@	$(am__mv) $(DEPDIR)/$*.Tpo $(DEPDIR)/$*.Plo
+@AMDEP_TRUE@@am__fastdepCCAS_FALSE@	source='$<' object='$@' libtool=yes @AMDEPBACKSLASH@
+@AMDEP_TRUE@@am__fastdepCCAS_FALSE@	DEPDIR=$(DEPDIR) $(CCASDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+@am__fastdepCCAS_FALSE@	$(LTCPPASCOMPILE) -c -o $@ $<
+
+libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la-filter_neon.lo: arm/filter_neon.S
+@am__fastdepCCAS_TRUE@	$(LIBTOOL)  $(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) --mode=compile $(CCAS) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_CPPFLAGS) $(CPPFLAGS) $(AM_CCASFLAGS) $(CCASFLAGS) -MT libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la-filter_neon.lo -MD -MP -MF $(DEPDIR)/libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la-filter_neon.Tpo -c -o libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la-filter_neon.lo `test -f 'arm/filter_neon.S' || echo '$(srcdir)/'`arm/filter_neon.S
+@am__fastdepCCAS_TRUE@	$(am__mv) $(DEPDIR)/libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la-filter_neon.Tpo $(DEPDIR)/libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la-filter_neon.Plo
+@AMDEP_TRUE@@am__fastdepCCAS_FALSE@	source='arm/filter_neon.S' object='libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la-filter_neon.lo' libtool=yes @AMDEPBACKSLASH@
+@AMDEP_TRUE@@am__fastdepCCAS_FALSE@	DEPDIR=$(DEPDIR) $(CCASDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+@am__fastdepCCAS_FALSE@	$(LIBTOOL)  $(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) --mode=compile $(CCAS) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_CPPFLAGS) $(CPPFLAGS) $(AM_CCASFLAGS) $(CCASFLAGS) -c -o libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la-filter_neon.lo `test -f 'arm/filter_neon.S' || echo '$(srcdir)/'`arm/filter_neon.S
+
 .c.o:
 @am__fastdepCC_TRUE@	$(COMPILE) -MT $@ -MD -MP -MF $(DEPDIR)/$*.Tpo -c -o $@ $<
 @am__fastdepCC_TRUE@	$(am__mv) $(DEPDIR)/$*.Tpo $(DEPDIR)/$*.Po
diff --git a/aclocal.m4 b/aclocal.m4
index e788a8959..732babbf5 100644
--- a/aclocal.m4
+++ b/aclocal.m4
@@ -2436,7 +2436,14 @@ freebsd* | dragonfly*)
     *) objformat=elf ;;
     esac
   fi
-  version_type=freebsd-$objformat
+  # Handle Gentoo/FreeBSD as it was Linux
+  case $host_vendor in
+    gentoo)
+      version_type=linux ;;
+    *)
+      version_type=freebsd-$objformat ;;
+  esac
+
   case $version_type in
     freebsd-elf*)
       library_names_spec='${libname}${release}${shared_ext}$versuffix ${libname}${release}${shared_ext} $libname${shared_ext}'
@@ -2447,6 +2454,12 @@ freebsd* | dragonfly*)
       library_names_spec='${libname}${release}${shared_ext}$versuffix $libname${shared_ext}$versuffix'
       need_version=yes
       ;;
+    linux)
+      library_names_spec='${libname}${release}${shared_ext}$versuffix ${libname}${release}${shared_ext}$major ${libname}${shared_ext}'
+      soname_spec='${libname}${release}${shared_ext}$major'
+      need_lib_prefix=no
+      need_version=no
+      ;;
   esac
   shlibpath_var=LD_LIBRARY_PATH
   case $host_os in
@@ -8482,6 +8495,28 @@ m4_ifndef([AC_AUTOCONF_VERSION],
   [m4_copy([m4_PACKAGE_VERSION], [AC_AUTOCONF_VERSION])])dnl
 _AM_AUTOCONF_VERSION(m4_defn([AC_AUTOCONF_VERSION]))])
 
+# Figure out how to run the assembler.                      -*- Autoconf -*-
+
+# Copyright (C) 2001, 2003, 2004, 2005, 2006  Free Software Foundation, Inc.
+#
+# This file is free software; the Free Software Foundation
+# gives unlimited permission to copy and/or distribute it,
+# with or without modifications, as long as this notice is preserved.
+
+# serial 5
+
+# AM_PROG_AS
+# ----------
+AC_DEFUN([AM_PROG_AS],
+[# By default we simply use the C compiler to build assembly code.
+AC_REQUIRE([AC_PROG_CC])
+test "${CCAS+set}" = set || CCAS=$CC
+test "${CCASFLAGS+set}" = set || CCASFLAGS=$CFLAGS
+AC_ARG_VAR([CCAS],      [assembler compiler command (defaults to CC)])
+AC_ARG_VAR([CCASFLAGS], [assembler compiler flags (defaults to CFLAGS)])
+_AM_IF_OPTION([no-dependencies],, [_AM_DEPENDENCIES([CCAS])])dnl
+])
+
 # AM_AUX_DIR_EXPAND                                         -*- Autoconf -*-
 
 # Copyright (C) 2001, 2003, 2005  Free Software Foundation, Inc.
diff --git a/config.guess b/config.guess
index dc84c68ef..8ca32db96 100644
--- a/config.guess
+++ b/config.guess
@@ -1,10 +1,10 @@
 #! /bin/sh
 # Attempt to guess a canonical system name.
 #   Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
-#   2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
-#   Free Software Foundation, Inc.
+#   2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010,
+#   2011 Free Software Foundation, Inc.
 
-timestamp='2009-11-20'
+timestamp='2011-02-02'
 
 # This file is free software; you can redistribute it and/or modify it
 # under the terms of the GNU General Public License as published by
@@ -56,8 +56,9 @@ version="\
 GNU config.guess ($timestamp)
 
 Originally written by Per Bothner.
-Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001,
-2002, 2003, 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
+Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
+2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Free
+Software Foundation, Inc.
 
 This is free software; see the source for copying conditions.  There is NO
 warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE."
@@ -139,6 +140,29 @@ UNAME_RELEASE=`(uname -r) 2>/dev/null` || UNAME_RELEASE=unknown
 UNAME_SYSTEM=`(uname -s) 2>/dev/null`  || UNAME_SYSTEM=unknown
 UNAME_VERSION=`(uname -v) 2>/dev/null` || UNAME_VERSION=unknown
 
+case "${UNAME_SYSTEM}" in
+Linux|GNU/*)
+	eval $set_cc_for_build
+	cat <<-EOF > $dummy.c
+	#include <features.h>
+	#ifdef __UCLIBC__
+	# ifdef __UCLIBC_CONFIG_VERSION__
+	LIBC=uclibc __UCLIBC_CONFIG_VERSION__
+	# else
+	LIBC=uclibc
+	# endif
+	#else
+	# ifdef __dietlibc__
+	LIBC=dietlibc
+	# else
+	LIBC=gnu
+	# endif
+	#endif
+	EOF
+	eval `$CC_FOR_BUILD -E $dummy.c 2>/dev/null | grep '^LIBC'`
+	;;
+esac
+
 # Note: order is significant - the case branches are not exclusive.
 
 case "${UNAME_MACHINE}:${UNAME_SYSTEM}:${UNAME_RELEASE}:${UNAME_VERSION}" in
@@ -180,7 +204,7 @@ case "${UNAME_MACHINE}:${UNAME_SYSTEM}:${UNAME_RELEASE}:${UNAME_VERSION}" in
 		fi
 		;;
 	    *)
-	        os=netbsd
+		os=netbsd
 		;;
 	esac
 	# The OS release
@@ -223,7 +247,7 @@ case "${UNAME_MACHINE}:${UNAME_SYSTEM}:${UNAME_RELEASE}:${UNAME_VERSION}" in
 		UNAME_RELEASE=`/usr/sbin/sizer -v | awk '{print $3}'`
 		;;
 	*5.*)
-	        UNAME_RELEASE=`/usr/sbin/sizer -v | awk '{print $4}'`
+		UNAME_RELEASE=`/usr/sbin/sizer -v | awk '{print $4}'`
 		;;
 	esac
 	# According to Compaq, /usr/sbin/psrinfo has been available on
@@ -269,7 +293,10 @@ case "${UNAME_MACHINE}:${UNAME_SYSTEM}:${UNAME_RELEASE}:${UNAME_VERSION}" in
 	# A Xn.n version is an unreleased experimental baselevel.
 	# 1.2 uses "1.2" for uname -r.
 	echo ${UNAME_MACHINE}-dec-osf`echo ${UNAME_RELEASE} | sed -e 's/^[PVTX]//' | tr 'ABCDEFGHIJKLMNOPQRSTUVWXYZ' 'abcdefghijklmnopqrstuvwxyz'`
-	exit ;;
+	# Reset EXIT trap before exiting to avoid spurious non-zero exit code.
+	exitcode=$?
+	trap '' 0
+	exit $exitcode ;;
     Alpha\ *:Windows_NT*:*)
 	# How do we know it's Interix rather than the generic POSIX subsystem?
 	# Should we change UNAME_MACHINE based on the output of uname instead
@@ -295,7 +322,7 @@ case "${UNAME_MACHINE}:${UNAME_SYSTEM}:${UNAME_RELEASE}:${UNAME_VERSION}" in
 	echo s390-ibm-zvmoe
 	exit ;;
     *:OS400:*:*)
-        echo powerpc-ibm-os400
+	echo powerpc-ibm-os400
 	exit ;;
     arm:RISC*:1.[012]*:*|arm:riscix:1.[012]*:*)
 	echo arm-acorn-riscix${UNAME_RELEASE}
@@ -394,23 +421,23 @@ case "${UNAME_MACHINE}:${UNAME_SYSTEM}:${UNAME_RELEASE}:${UNAME_VERSION}" in
     # MiNT.  But MiNT is downward compatible to TOS, so this should
     # be no problem.
     atarist[e]:*MiNT:*:* | atarist[e]:*mint:*:* | atarist[e]:*TOS:*:*)
-        echo m68k-atari-mint${UNAME_RELEASE}
+	echo m68k-atari-mint${UNAME_RELEASE}
 	exit ;;
     atari*:*MiNT:*:* | atari*:*mint:*:* | atarist[e]:*TOS:*:*)
 	echo m68k-atari-mint${UNAME_RELEASE}
-        exit ;;
+	exit ;;
     *falcon*:*MiNT:*:* | *falcon*:*mint:*:* | *falcon*:*TOS:*:*)
-        echo m68k-atari-mint${UNAME_RELEASE}
+	echo m68k-atari-mint${UNAME_RELEASE}
 	exit ;;
     milan*:*MiNT:*:* | milan*:*mint:*:* | *milan*:*TOS:*:*)
-        echo m68k-milan-mint${UNAME_RELEASE}
-        exit ;;
+	echo m68k-milan-mint${UNAME_RELEASE}
+	exit ;;
     hades*:*MiNT:*:* | hades*:*mint:*:* | *hades*:*TOS:*:*)
-        echo m68k-hades-mint${UNAME_RELEASE}
-        exit ;;
+	echo m68k-hades-mint${UNAME_RELEASE}
+	exit ;;
     *:*MiNT:*:* | *:*mint:*:* | *:*TOS:*:*)
-        echo m68k-unknown-mint${UNAME_RELEASE}
-        exit ;;
+	echo m68k-unknown-mint${UNAME_RELEASE}
+	exit ;;
     m68k:machten:*:*)
 	echo m68k-apple-machten${UNAME_RELEASE}
 	exit ;;
@@ -480,8 +507,8 @@ EOF
 	echo m88k-motorola-sysv3
 	exit ;;
     AViiON:dgux:*:*)
-        # DG/UX returns AViiON for all architectures
-        UNAME_PROCESSOR=`/usr/bin/uname -p`
+	# DG/UX returns AViiON for all architectures
+	UNAME_PROCESSOR=`/usr/bin/uname -p`
 	if [ $UNAME_PROCESSOR = mc88100 ] || [ $UNAME_PROCESSOR = mc88110 ]
 	then
 	    if [ ${TARGET_BINARY_INTERFACE}x = m88kdguxelfx ] || \
@@ -494,7 +521,7 @@ EOF
 	else
 	    echo i586-dg-dgux${UNAME_RELEASE}
 	fi
- 	exit ;;
+	exit ;;
     M88*:DolphinOS:*:*)	# DolphinOS (SVR3)
 	echo m88k-dolphin-sysv3
 	exit ;;
@@ -551,7 +578,7 @@ EOF
 		echo rs6000-ibm-aix3.2
 	fi
 	exit ;;
-    *:AIX:*:[456])
+    *:AIX:*:[4567])
 	IBM_CPU_ID=`/usr/sbin/lsdev -C -c processor -S available | sed 1q | awk '{ print $1 }'`
 	if /usr/sbin/lsattr -El ${IBM_CPU_ID} | grep ' POWER' >/dev/null 2>&1; then
 		IBM_ARCH=rs6000
@@ -594,52 +621,52 @@ EOF
 	    9000/[678][0-9][0-9])
 		if [ -x /usr/bin/getconf ]; then
 		    sc_cpu_version=`/usr/bin/getconf SC_CPU_VERSION 2>/dev/null`
-                    sc_kernel_bits=`/usr/bin/getconf SC_KERNEL_BITS 2>/dev/null`
-                    case "${sc_cpu_version}" in
-                      523) HP_ARCH="hppa1.0" ;; # CPU_PA_RISC1_0
-                      528) HP_ARCH="hppa1.1" ;; # CPU_PA_RISC1_1
-                      532)                      # CPU_PA_RISC2_0
-                        case "${sc_kernel_bits}" in
-                          32) HP_ARCH="hppa2.0n" ;;
-                          64) HP_ARCH="hppa2.0w" ;;
+		    sc_kernel_bits=`/usr/bin/getconf SC_KERNEL_BITS 2>/dev/null`
+		    case "${sc_cpu_version}" in
+		      523) HP_ARCH="hppa1.0" ;; # CPU_PA_RISC1_0
+		      528) HP_ARCH="hppa1.1" ;; # CPU_PA_RISC1_1
+		      532)                      # CPU_PA_RISC2_0
+			case "${sc_kernel_bits}" in
+			  32) HP_ARCH="hppa2.0n" ;;
+			  64) HP_ARCH="hppa2.0w" ;;
 			  '') HP_ARCH="hppa2.0" ;;   # HP-UX 10.20
-                        esac ;;
-                    esac
+			esac ;;
+		    esac
 		fi
 		if [ "${HP_ARCH}" = "" ]; then
 		    eval $set_cc_for_build
-		    sed 's/^              //' << EOF >$dummy.c
+		    sed 's/^		//' << EOF >$dummy.c
 
-              #define _HPUX_SOURCE
-              #include <stdlib.h>
-              #include <unistd.h>
+		#define _HPUX_SOURCE
+		#include <stdlib.h>
+		#include <unistd.h>
 
-              int main ()
-              {
-              #if defined(_SC_KERNEL_BITS)
-                  long bits = sysconf(_SC_KERNEL_BITS);
-              #endif
-                  long cpu  = sysconf (_SC_CPU_VERSION);
+		int main ()
+		{
+		#if defined(_SC_KERNEL_BITS)
+		    long bits = sysconf(_SC_KERNEL_BITS);
+		#endif
+		    long cpu  = sysconf (_SC_CPU_VERSION);
 
-                  switch (cpu)
-              	{
-              	case CPU_PA_RISC1_0: puts ("hppa1.0"); break;
-              	case CPU_PA_RISC1_1: puts ("hppa1.1"); break;
-              	case CPU_PA_RISC2_0:
-              #if defined(_SC_KERNEL_BITS)
-              	    switch (bits)
-              		{
-              		case 64: puts ("hppa2.0w"); break;
-              		case 32: puts ("hppa2.0n"); break;
-              		default: puts ("hppa2.0"); break;
-              		} break;
-              #else  /* !defined(_SC_KERNEL_BITS) */
-              	    puts ("hppa2.0"); break;
-              #endif
-              	default: puts ("hppa1.0"); break;
-              	}
-                  exit (0);
-              }
+		    switch (cpu)
+			{
+			case CPU_PA_RISC1_0: puts ("hppa1.0"); break;
+			case CPU_PA_RISC1_1: puts ("hppa1.1"); break;
+			case CPU_PA_RISC2_0:
+		#if defined(_SC_KERNEL_BITS)
+			    switch (bits)
+				{
+				case 64: puts ("hppa2.0w"); break;
+				case 32: puts ("hppa2.0n"); break;
+				default: puts ("hppa2.0"); break;
+				} break;
+		#else  /* !defined(_SC_KERNEL_BITS) */
+			    puts ("hppa2.0"); break;
+		#endif
+			default: puts ("hppa1.0"); break;
+			}
+		    exit (0);
+		}
 EOF
 		    (CCOPTS= $CC_FOR_BUILD -o $dummy $dummy.c 2>/dev/null) && HP_ARCH=`$dummy`
 		    test -z "$HP_ARCH" && HP_ARCH=hppa
@@ -730,22 +757,22 @@ EOF
 	exit ;;
     C1*:ConvexOS:*:* | convex:ConvexOS:C1*:*)
 	echo c1-convex-bsd
-        exit ;;
+	exit ;;
     C2*:ConvexOS:*:* | convex:ConvexOS:C2*:*)
 	if getsysinfo -f scalar_acc
 	then echo c32-convex-bsd
 	else echo c2-convex-bsd
 	fi
-        exit ;;
+	exit ;;
     C34*:ConvexOS:*:* | convex:ConvexOS:C34*:*)
 	echo c34-convex-bsd
-        exit ;;
+	exit ;;
     C38*:ConvexOS:*:* | convex:ConvexOS:C38*:*)
 	echo c38-convex-bsd
-        exit ;;
+	exit ;;
     C4*:ConvexOS:*:* | convex:ConvexOS:C4*:*)
 	echo c4-convex-bsd
-        exit ;;
+	exit ;;
     CRAY*Y-MP:*:*:*)
 	echo ymp-cray-unicos${UNAME_RELEASE} | sed -e 's/\.[^.]*$/.X/'
 	exit ;;
@@ -769,14 +796,14 @@ EOF
 	exit ;;
     F30[01]:UNIX_System_V:*:* | F700:UNIX_System_V:*:*)
 	FUJITSU_PROC=`uname -m | tr 'ABCDEFGHIJKLMNOPQRSTUVWXYZ' 'abcdefghijklmnopqrstuvwxyz'`
-        FUJITSU_SYS=`uname -p | tr 'ABCDEFGHIJKLMNOPQRSTUVWXYZ' 'abcdefghijklmnopqrstuvwxyz' | sed -e 's/\///'`
-        FUJITSU_REL=`echo ${UNAME_RELEASE} | sed -e 's/ /_/'`
-        echo "${FUJITSU_PROC}-fujitsu-${FUJITSU_SYS}${FUJITSU_REL}"
-        exit ;;
+	FUJITSU_SYS=`uname -p | tr 'ABCDEFGHIJKLMNOPQRSTUVWXYZ' 'abcdefghijklmnopqrstuvwxyz' | sed -e 's/\///'`
+	FUJITSU_REL=`echo ${UNAME_RELEASE} | sed -e 's/ /_/'`
+	echo "${FUJITSU_PROC}-fujitsu-${FUJITSU_SYS}${FUJITSU_REL}"
+	exit ;;
     5000:UNIX_System_V:4.*:*)
-        FUJITSU_SYS=`uname -p | tr 'ABCDEFGHIJKLMNOPQRSTUVWXYZ' 'abcdefghijklmnopqrstuvwxyz' | sed -e 's/\///'`
-        FUJITSU_REL=`echo ${UNAME_RELEASE} | tr 'ABCDEFGHIJKLMNOPQRSTUVWXYZ' 'abcdefghijklmnopqrstuvwxyz' | sed -e 's/ /_/'`
-        echo "sparc-fujitsu-${FUJITSU_SYS}${FUJITSU_REL}"
+	FUJITSU_SYS=`uname -p | tr 'ABCDEFGHIJKLMNOPQRSTUVWXYZ' 'abcdefghijklmnopqrstuvwxyz' | sed -e 's/\///'`
+	FUJITSU_REL=`echo ${UNAME_RELEASE} | tr 'ABCDEFGHIJKLMNOPQRSTUVWXYZ' 'abcdefghijklmnopqrstuvwxyz' | sed -e 's/ /_/'`
+	echo "sparc-fujitsu-${FUJITSU_SYS}${FUJITSU_REL}"
 	exit ;;
     i*86:BSD/386:*:* | i*86:BSD/OS:*:* | *:Ascend\ Embedded/OS:*:*)
 	echo ${UNAME_MACHINE}-pc-bsdi${UNAME_RELEASE}
@@ -804,14 +831,14 @@ EOF
 	echo ${UNAME_MACHINE}-pc-mingw32
 	exit ;;
     i*:windows32*:*)
-    	# uname -m includes "-pc" on this system.
-    	echo ${UNAME_MACHINE}-mingw32
+	# uname -m includes "-pc" on this system.
+	echo ${UNAME_MACHINE}-mingw32
 	exit ;;
     i*:PW*:*)
 	echo ${UNAME_MACHINE}-pc-pw32
 	exit ;;
     *:Interix*:*)
-    	case ${UNAME_MACHINE} in
+	case ${UNAME_MACHINE} in
 	    x86)
 		echo i586-pc-interix${UNAME_RELEASE}
 		exit ;;
@@ -848,11 +875,11 @@ EOF
 	exit ;;
     *:GNU:*:*)
 	# the GNU system
-	echo `echo ${UNAME_MACHINE}|sed -e 's,[-/].*$,,'`-unknown-gnu`echo ${UNAME_RELEASE}|sed -e 's,/.*$,,'`
+	echo `echo ${UNAME_MACHINE}|sed -e 's,[-/].*$,,'`-unknown-${LIBC}`echo ${UNAME_RELEASE}|sed -e 's,/.*$,,'`
 	exit ;;
     *:GNU/*:*:*)
 	# other systems with GNU libc and userland
-	echo ${UNAME_MACHINE}-unknown-`echo ${UNAME_SYSTEM} | sed 's,^[^/]*/,,' | tr '[A-Z]' '[a-z]'``echo ${UNAME_RELEASE}|sed -e 's/[-(].*//'`-gnu
+	echo ${UNAME_MACHINE}-unknown-`echo ${UNAME_SYSTEM} | sed 's,^[^/]*/,,' | tr '[A-Z]' '[a-z]'``echo ${UNAME_RELEASE}|sed -e 's/[-(].*//'`-${LIBC}
 	exit ;;
     i*86:Minix:*:*)
 	echo ${UNAME_MACHINE}-pc-minix
@@ -866,52 +893,44 @@ EOF
 	  EV6)   UNAME_MACHINE=alphaev6 ;;
 	  EV67)  UNAME_MACHINE=alphaev67 ;;
 	  EV68*) UNAME_MACHINE=alphaev68 ;;
-        esac
+	esac
 	objdump --private-headers /bin/sh | grep -q ld.so.1
-	if test "$?" = 0 ; then LIBC="libc1" ; else LIBC="" ; fi
-	echo ${UNAME_MACHINE}-unknown-linux-gnu${LIBC}
+	if test "$?" = 0 ; then LIBC="gnulibc1" ; fi
+	echo ${UNAME_MACHINE}-unknown-linux-${LIBC}
 	exit ;;
     arm*:Linux:*:*)
 	eval $set_cc_for_build
 	if echo __ARM_EABI__ | $CC_FOR_BUILD -E - 2>/dev/null \
 	    | grep -q __ARM_EABI__
 	then
-	    echo ${UNAME_MACHINE}-unknown-linux-gnu
+	    echo ${UNAME_MACHINE}-unknown-linux-${LIBC}
 	else
-	    echo ${UNAME_MACHINE}-unknown-linux-gnueabi
+	    echo ${UNAME_MACHINE}-unknown-linux-${LIBC}eabi
 	fi
 	exit ;;
     avr32*:Linux:*:*)
-	echo ${UNAME_MACHINE}-unknown-linux-gnu
+	echo ${UNAME_MACHINE}-unknown-linux-${LIBC}
 	exit ;;
     cris:Linux:*:*)
-	echo cris-axis-linux-gnu
+	echo cris-axis-linux-${LIBC}
 	exit ;;
     crisv32:Linux:*:*)
-	echo crisv32-axis-linux-gnu
+	echo crisv32-axis-linux-${LIBC}
 	exit ;;
     frv:Linux:*:*)
-    	echo frv-unknown-linux-gnu
+	echo frv-unknown-linux-${LIBC}
 	exit ;;
     i*86:Linux:*:*)
-	LIBC=gnu
-	eval $set_cc_for_build
-	sed 's/^	//' << EOF >$dummy.c
-	#ifdef __dietlibc__
-	LIBC=dietlibc
-	#endif
-EOF
-	eval `$CC_FOR_BUILD -E $dummy.c 2>/dev/null | grep '^LIBC'`
-	echo "${UNAME_MACHINE}-pc-linux-${LIBC}"
+	echo ${UNAME_MACHINE}-pc-linux-${LIBC}
 	exit ;;
     ia64:Linux:*:*)
-	echo ${UNAME_MACHINE}-unknown-linux-gnu
+	echo ${UNAME_MACHINE}-unknown-linux-${LIBC}
 	exit ;;
     m32r*:Linux:*:*)
-	echo ${UNAME_MACHINE}-unknown-linux-gnu
+	echo ${UNAME_MACHINE}-unknown-linux-${LIBC}
 	exit ;;
     m68*:Linux:*:*)
-	echo ${UNAME_MACHINE}-unknown-linux-gnu
+	echo ${UNAME_MACHINE}-unknown-linux-${LIBC}
 	exit ;;
     mips:Linux:*:* | mips64:Linux:*:*)
 	eval $set_cc_for_build
@@ -930,51 +949,54 @@ EOF
 	#endif
 EOF
 	eval `$CC_FOR_BUILD -E $dummy.c 2>/dev/null | grep '^CPU'`
-	test x"${CPU}" != x && { echo "${CPU}-unknown-linux-gnu"; exit; }
+	test x"${CPU}" != x && { echo "${CPU}-unknown-linux-${LIBC}"; exit; }
 	;;
     or32:Linux:*:*)
-	echo or32-unknown-linux-gnu
+	echo or32-unknown-linux-${LIBC}
 	exit ;;
     padre:Linux:*:*)
-	echo sparc-unknown-linux-gnu
+	echo sparc-unknown-linux-${LIBC}
 	exit ;;
     parisc64:Linux:*:* | hppa64:Linux:*:*)
-	echo hppa64-unknown-linux-gnu
+	echo hppa64-unknown-linux-${LIBC}
 	exit ;;
     parisc:Linux:*:* | hppa:Linux:*:*)
 	# Look for CPU level
 	case `grep '^cpu[^a-z]*:' /proc/cpuinfo 2>/dev/null | cut -d' ' -f2` in
-	  PA7*) echo hppa1.1-unknown-linux-gnu ;;
-	  PA8*) echo hppa2.0-unknown-linux-gnu ;;
-	  *)    echo hppa-unknown-linux-gnu ;;
+	  PA7*) echo hppa1.1-unknown-linux-${LIBC} ;;
+	  PA8*) echo hppa2.0-unknown-linux-${LIBC} ;;
+	  *)    echo hppa-unknown-linux-${LIBC} ;;
 	esac
 	exit ;;
     ppc64:Linux:*:*)
-	echo powerpc64-unknown-linux-gnu
+	echo powerpc64-unknown-linux-${LIBC}
 	exit ;;
     ppc:Linux:*:*)
-	echo powerpc-unknown-linux-gnu
+	echo powerpc-unknown-linux-${LIBC}
 	exit ;;
     s390:Linux:*:* | s390x:Linux:*:*)
 	echo ${UNAME_MACHINE}-ibm-linux
 	exit ;;
     sh64*:Linux:*:*)
-    	echo ${UNAME_MACHINE}-unknown-linux-gnu
+	echo ${UNAME_MACHINE}-unknown-linux-${LIBC}
 	exit ;;
     sh*:Linux:*:*)
-	echo ${UNAME_MACHINE}-unknown-linux-gnu
+	echo ${UNAME_MACHINE}-unknown-linux-${LIBC}
 	exit ;;
     sparc:Linux:*:* | sparc64:Linux:*:*)
-	echo ${UNAME_MACHINE}-unknown-linux-gnu
+	echo ${UNAME_MACHINE}-unknown-linux-${LIBC}
+	exit ;;
+    tile*:Linux:*:*)
+	echo ${UNAME_MACHINE}-tilera-linux-gnu
 	exit ;;
     vax:Linux:*:*)
-	echo ${UNAME_MACHINE}-dec-linux-gnu
+	echo ${UNAME_MACHINE}-dec-linux-${LIBC}
 	exit ;;
     x86_64:Linux:*:*)
-	echo x86_64-unknown-linux-gnu
+	echo x86_64-unknown-linux-${LIBC}
 	exit ;;
     xtensa*:Linux:*:*)
-    	echo ${UNAME_MACHINE}-unknown-linux-gnu
+	echo ${UNAME_MACHINE}-unknown-linux-${LIBC}
 	exit ;;
     i*86:DYNIX/ptx:4*:*)
 	# ptx 4.0 does uname -s correctly, with DYNIX/ptx in there.
@@ -983,11 +1005,11 @@ EOF
 	echo i386-sequent-sysv4
 	exit ;;
     i*86:UNIX_SV:4.2MP:2.*)
-        # Unixware is an offshoot of SVR4, but it has its own version
-        # number series starting with 2...
-        # I am not positive that other SVR4 systems won't match this,
+	# Unixware is an offshoot of SVR4, but it has its own version
+	# number series starting with 2...
+	# I am not positive that other SVR4 systems won't match this,
 	# I just have to hope.  -- rms.
-        # Use sysv4.2uw... so that sysv4* matches it.
+	# Use sysv4.2uw... so that sysv4* matches it.
 	echo ${UNAME_MACHINE}-pc-sysv4.2uw${UNAME_VERSION}
 	exit ;;
     i*86:OS/2:*:*)
@@ -1019,7 +1041,7 @@ EOF
 	fi
 	exit ;;
     i*86:*:5:[678]*)
-    	# UnixWare 7.x, OpenUNIX and OpenServer 6.
+	# UnixWare 7.x, OpenUNIX and OpenServer 6.
 	case `/bin/uname -X | grep "^Machine"` in
 	    *486*)	     UNAME_MACHINE=i486 ;;
 	    *Pentium)	     UNAME_MACHINE=i586 ;;
@@ -1047,13 +1069,13 @@ EOF
 	exit ;;
     pc:*:*:*)
 	# Left here for compatibility:
-        # uname -m prints for DJGPP always 'pc', but it prints nothing about
-        # the processor, so we play safe by assuming i586.
+	# uname -m prints for DJGPP always 'pc', but it prints nothing about
+	# the processor, so we play safe by assuming i586.
 	# Note: whatever this is, it MUST be the same as what config.sub
 	# prints for the "djgpp" host, or else GDB configury will decide that
 	# this is a cross-build.
 	echo i586-pc-msdosdjgpp
-        exit ;;
+	exit ;;
     Intel:Mach:3*:*)
 	echo i386-pc-mach3
 	exit ;;
@@ -1088,8 +1110,8 @@ EOF
 	/bin/uname -p 2>/dev/null | /bin/grep entium >/dev/null \
 	  && { echo i586-ncr-sysv4.3${OS_REL}; exit; } ;;
     3[34]??:*:4.0:* | 3[34]??,*:*:4.0:*)
-        /bin/uname -p 2>/dev/null | grep 86 >/dev/null \
-          && { echo i486-ncr-sysv4; exit; } ;;
+	/bin/uname -p 2>/dev/null | grep 86 >/dev/null \
+	  && { echo i486-ncr-sysv4; exit; } ;;
     NCR*:*:4.2:* | MPRAS*:*:4.2:*)
 	OS_REL='.3'
 	test -r /etc/.relid \
@@ -1132,10 +1154,10 @@ EOF
 		echo ns32k-sni-sysv
 	fi
 	exit ;;
-    PENTIUM:*:4.0*:*) # Unisys `ClearPath HMP IX 4000' SVR4/MP effort
-                      # says <Richard.M.Bartel@ccMail.Census.GOV>
-        echo i586-unisys-sysv4
-        exit ;;
+    PENTIUM:*:4.0*:*)	# Unisys `ClearPath HMP IX 4000' SVR4/MP effort
+			# says <Richard.M.Bartel@ccMail.Census.GOV>
+	echo i586-unisys-sysv4
+	exit ;;
     *:UNIX_System_V:4*:FTX*)
 	# From Gerald Hewes <hewes@openmarket.com>.
 	# How about differentiating between stratus architectures? -djm
@@ -1161,11 +1183,11 @@ EOF
 	exit ;;
     R[34]000:*System_V*:*:* | R4000:UNIX_SYSV:*:* | R*000:UNIX_SV:*:*)
 	if [ -d /usr/nec ]; then
-	        echo mips-nec-sysv${UNAME_RELEASE}
+		echo mips-nec-sysv${UNAME_RELEASE}
 	else
-	        echo mips-unknown-sysv${UNAME_RELEASE}
+		echo mips-unknown-sysv${UNAME_RELEASE}
 	fi
-        exit ;;
+	exit ;;
     BeBox:BeOS:*:*)	# BeOS running on hardware made by Be, PPC only.
 	echo powerpc-be-beos
 	exit ;;
@@ -1230,6 +1252,9 @@ EOF
     *:QNX:*:4*)
 	echo i386-pc-qnx
 	exit ;;
+    NEO-?:NONSTOP_KERNEL:*:*)
+	echo neo-tandem-nsk${UNAME_RELEASE}
+	exit ;;
     NSE-?:NONSTOP_KERNEL:*:*)
 	echo nse-tandem-nsk${UNAME_RELEASE}
 	exit ;;
@@ -1275,13 +1300,13 @@ EOF
 	echo pdp10-unknown-its
 	exit ;;
     SEI:*:*:SEIUX)
-        echo mips-sei-seiux${UNAME_RELEASE}
+	echo mips-sei-seiux${UNAME_RELEASE}
 	exit ;;
     *:DragonFly:*:*)
 	echo ${UNAME_MACHINE}-unknown-dragonfly`echo ${UNAME_RELEASE}|sed -e 's/[-(].*//'`
 	exit ;;
     *:*VMS:*:*)
-    	UNAME_MACHINE=`(uname -p) 2>/dev/null`
+	UNAME_MACHINE=`(uname -p) 2>/dev/null`
 	case "${UNAME_MACHINE}" in
 	    A*) echo alpha-dec-vms ; exit ;;
 	    I*) echo ia64-dec-vms ; exit ;;
@@ -1321,11 +1346,11 @@ main ()
 #include <sys/param.h>
   printf ("m68k-sony-newsos%s\n",
 #ifdef NEWSOS4
-          "4"
+	"4"
 #else
-	  ""
+	""
 #endif
-         ); exit (0);
+	); exit (0);
 #endif
 #endif
 
diff --git a/config.h.in b/config.h.in
index fb2349568..657a003c6 100644
--- a/config.h.in
+++ b/config.h.in
@@ -70,6 +70,12 @@
 /* Define to the version of this package. */
 #undef PACKAGE_VERSION
 
+/* Align row buffers */
+#undef PNG_ALIGNED_MEMORY_SUPPORTED
+
+/* Enable ARM NEON optmizations */
+#undef PNG_ARM_NEON
+
 /* Define to 1 if you have the ANSI C header files. */
 #undef STDC_HEADERS
 
diff --git a/config.sub b/config.sub
index 2a55a5075..eda465bce 100644
--- a/config.sub
+++ b/config.sub
@@ -1,10 +1,10 @@
 #! /bin/sh
 # Configuration validation subroutine script.
 #   Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
-#   2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
-#   Free Software Foundation, Inc.
+#   2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010,
+#   2011 Free Software Foundation, Inc.
 
-timestamp='2009-11-20'
+timestamp='2011-02-02'
 
 # This file is (in principle) common to ALL GNU software.
 # The presence of a machine in this file suggests that SOME GNU software
@@ -75,8 +75,9 @@ Report bugs and patches to <config-patches@gnu.org>."
 version="\
 GNU config.sub ($timestamp)
 
-Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001,
-2002, 2003, 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
+Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
+2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 Free
+Software Foundation, Inc.
 
 This is free software; see the source for copying conditions.  There is NO
 warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE."
@@ -123,8 +124,9 @@ esac
 # Here we must recognize all the valid KERNEL-OS combinations.
 maybe_os=`echo $1 | sed 's/^\(.*\)-\([^-]*-[^-]*\)$/\2/'`
 case $maybe_os in
-  nto-qnx* | linux-gnu* | linux-dietlibc | linux-newlib* | linux-uclibc* | \
-  uclinux-uclibc* | uclinux-gnu* | kfreebsd*-gnu* | knetbsd*-gnu* | netbsd*-gnu* | \
+  nto-qnx* | linux-gnu* | linux-android* | linux-dietlibc | linux-newlib* | \
+  linux-uclibc* | uclinux-uclibc* | uclinux-gnu* | kfreebsd*-gnu* | \
+  knetbsd*-gnu* | netbsd*-gnu* | \
   kopensolaris*-gnu* | \
   storm-chaos* | os2-emx* | rtmk-nova*)
     os=-$maybe_os
@@ -156,8 +158,8 @@ case $os in
 		os=
 		basic_machine=$1
 		;;
-        -bluegene*)
-	        os=-cnk
+	-bluegene*)
+		os=-cnk
 		;;
 	-sim | -cisco | -oki | -wec | -winbond)
 		os=
@@ -173,10 +175,10 @@ case $os in
 		os=-chorusos
 		basic_machine=$1
 		;;
- 	-chorusrdb)
- 		os=-chorusrdb
+	-chorusrdb)
+		os=-chorusrdb
 		basic_machine=$1
- 		;;
+		;;
 	-hiux*)
 		os=-hiuxwe2
 		;;
@@ -251,7 +253,7 @@ case $basic_machine in
 	| arc | arm | arm[bl]e | arme[lb] | armv[2345] | armv[345][lb] | avr | avr32 \
 	| bfin \
 	| c4x | clipper \
-	| d10v | d30v | dlx | dsp16xx \
+	| d10v | d30v | dlx | dsp16xx | dvp \
 	| fido | fr30 | frv \
 	| h8300 | h8500 | hppa | hppa1.[01] | hppa2.0 | hppa2.0[nw] | hppa64 \
 	| i370 | i860 | i960 | ia64 \
@@ -281,6 +283,7 @@ case $basic_machine in
 	| moxie \
 	| mt \
 	| msp430 \
+	| nds32 | nds32le | nds32be \
 	| nios | nios2 \
 	| ns16k | ns32k \
 	| or32 \
@@ -294,7 +297,7 @@ case $basic_machine in
 	| sparc | sparc64 | sparc64b | sparc64v | sparc86x | sparclet | sparclite \
 	| sparcv8 | sparcv9 | sparcv9b | sparcv9v \
 	| spu | strongarm \
-	| tahoe | thumb | tic4x | tic80 | tron \
+	| tahoe | thumb | tic4x | tic54x | tic55x | tic6x | tic80 | tron \
 	| ubicom32 \
 	| v850 | v850e \
 	| we32k \
@@ -302,6 +305,15 @@ case $basic_machine in
 	| z8k | z80)
 		basic_machine=$basic_machine-unknown
 		;;
+	c54x)
+		basic_machine=tic54x-unknown
+		;;
+	c55x)
+		basic_machine=tic55x-unknown
+		;;
+	c6x)
+		basic_machine=tic6x-unknown
+		;;
 	m6811 | m68hc11 | m6812 | m68hc12 | picochip)
 		# Motorola 68HC11/12.
 		basic_machine=$basic_machine-unknown
@@ -333,7 +345,7 @@ case $basic_machine in
 	| arm-*  | armbe-* | armle-* | armeb-* | armv*-* \
 	| avr-* | avr32-* \
 	| bfin-* | bs2000-* \
-	| c[123]* | c30-* | [cjt]90-* | c4x-* | c54x-* | c55x-* | c6x-* \
+	| c[123]* | c30-* | [cjt]90-* | c4x-* \
 	| clipper-* | craynv-* | cydra-* \
 	| d10v-* | d30v-* | dlx-* \
 	| elxsi-* \
@@ -367,6 +379,7 @@ case $basic_machine in
 	| mmix-* \
 	| mt-* \
 	| msp430-* \
+	| nds32-* | nds32le-* | nds32be-* \
 	| nios-* | nios2-* \
 	| none-* | np1-* | ns16k-* | ns32k-* \
 	| orion-* \
@@ -380,7 +393,8 @@ case $basic_machine in
 	| sparclite-* \
 	| sparcv8-* | sparcv9-* | sparcv9b-* | sparcv9v-* | strongarm-* | sv1-* | sx?-* \
 	| tahoe-* | thumb-* \
-	| tic30-* | tic4x-* | tic54x-* | tic55x-* | tic6x-* | tic80-* | tile-* \
+	| tic30-* | tic4x-* | tic54x-* | tic55x-* | tic6x-* | tic80-* \
+	| tile-* | tilegx-* \
 	| tron-* \
 	| ubicom32-* \
 	| v850-* | v850e-* | vax-* \
@@ -410,7 +424,7 @@ case $basic_machine in
 		basic_machine=a29k-amd
 		os=-udi
 		;;
-    	abacus)
+	abacus)
 		basic_machine=abacus-unknown
 		;;
 	adobe68k)
@@ -480,11 +494,20 @@ case $basic_machine in
 		basic_machine=powerpc-ibm
 		os=-cnk
 		;;
+	c54x-*)
+		basic_machine=tic54x-`echo $basic_machine | sed 's/^[^-]*-//'`
+		;;
+	c55x-*)
+		basic_machine=tic55x-`echo $basic_machine | sed 's/^[^-]*-//'`
+		;;
+	c6x-*)
+		basic_machine=tic6x-`echo $basic_machine | sed 's/^[^-]*-//'`
+		;;
 	c90)
 		basic_machine=c90-cray
 		os=-unicos
 		;;
-        cegcc)
+	cegcc)
 		basic_machine=arm-unknown
 		os=-cegcc
 		;;
@@ -516,7 +539,7 @@ case $basic_machine in
 		basic_machine=craynv-cray
 		os=-unicosmp
 		;;
-	cr16)
+	cr16 | cr16-*)
 		basic_machine=cr16-unknown
 		os=-elf
 		;;
@@ -732,7 +755,7 @@ case $basic_machine in
 		basic_machine=ns32k-utek
 		os=-sysv
 		;;
-        microblaze)
+	microblaze)
 		basic_machine=microblaze-xilinx
 		;;
 	mingw32)
@@ -750,6 +773,24 @@ case $basic_machine in
 		basic_machine=m68k-atari
 		os=-mint
 		;;
+	mipsEE* | ee | ps2)
+		basic_machine=mips64r5900el-scei
+		case $os in
+		    -linux*)
+			;;
+		    *)
+			os=-elf
+			;;
+		esac
+		;;
+	iop)
+		basic_machine=mipsel-scei
+		os=-irx
+		;;
+	dvp)
+		basic_machine=dvp-scei
+		os=-elf
+		;;
 	mips3*-*)
 		basic_machine=`echo $basic_machine | sed -e 's/mips3/mips64/'`
 		;;
@@ -839,6 +880,12 @@ case $basic_machine in
 	np1)
 		basic_machine=np1-gould
 		;;
+	neo-tandem)
+		basic_machine=neo-tandem
+		;;
+	nse-tandem)
+		basic_machine=nse-tandem
+		;;
 	nsr-tandem)
 		basic_machine=nsr-tandem
 		;;
@@ -1073,17 +1120,10 @@ case $basic_machine in
 		basic_machine=t90-cray
 		os=-unicos
 		;;
-	tic54x | c54x*)
-		basic_machine=tic54x-unknown
-		os=-coff
-		;;
-	tic55x | c55x*)
-		basic_machine=tic55x-unknown
-		os=-coff
-		;;
-	tic6x | c6x*)
-		basic_machine=tic6x-unknown
-		os=-coff
+	# This must be matched before tile*.
+	tilegx*)
+		basic_machine=tilegx-unknown
+		os=-linux-gnu
 		;;
 	tile*)
 		basic_machine=tile-unknown
@@ -1253,11 +1293,11 @@ esac
 if [ x"$os" != x"" ]
 then
 case $os in
-        # First match some system type aliases
-        # that might get confused with valid system types.
+	# First match some system type aliases
+	# that might get confused with valid system types.
 	# -solaris* is a basic system type, with this one exception.
-        -auroraux)
-	        os=-auroraux
+	-auroraux)
+		os=-auroraux
 		;;
 	-solaris1 | -solaris1.*)
 		os=`echo $os | sed -e 's|solaris1|sunos4|'`
@@ -1294,11 +1334,12 @@ case $os in
 	      | -udi* | -eabi* | -lites* | -ieee* | -go32* | -aux* \
 	      | -chorusos* | -chorusrdb* | -cegcc* \
 	      | -cygwin* | -pe* | -psos* | -moss* | -proelf* | -rtems* \
-	      | -mingw32* | -linux-gnu* | -linux-newlib* | -linux-uclibc* \
+	      | -mingw32* | -linux-gnu* | -linux-android* \
+	      | -linux-newlib* | -linux-uclibc* \
 	      | -uxpv* | -beos* | -mpeix* | -udk* \
 	      | -interix* | -uwin* | -mks* | -rhapsody* | -darwin* | -opened* \
 	      | -openstep* | -oskit* | -conix* | -pw32* | -nonstopux* \
-	      | -storm-chaos* | -tops10* | -tenex* | -tops20* | -its* \
+	      | -storm-chaos* | -tops10* | -tenex* | -tops20* | -its* | -irx* \
 	      | -os2* | -vos* | -palmos* | -uclinux* | -nucleus* \
 	      | -morphos* | -superux* | -rtmk* | -rtmk-nova* | -windiss* \
 	      | -powermax* | -dnix* | -nx6 | -nx7 | -sei* | -dragonfly* \
@@ -1341,7 +1382,7 @@ case $os in
 	-opened*)
 		os=-openedition
 		;;
-        -os400*)
+	-os400*)
 		os=-os400
 		;;
 	-wince*)
@@ -1390,7 +1431,7 @@ case $os in
 	-sinix*)
 		os=-sysv4
 		;;
-        -tpf*)
+	-tpf*)
 		os=-tpf
 		;;
 	-triton*)
@@ -1435,6 +1476,8 @@ case $os in
 	-dicos*)
 		os=-dicos
 		;;
+	-nacl*)
+		;;
 	-none)
 		;;
 	*)
@@ -1457,10 +1500,10 @@ else
 # system, and we'll never get to this point.
 
 case $basic_machine in
-        score-*)
+	score-*)
 		os=-elf
 		;;
-        spu-*)
+	spu-*)
 		os=-elf
 		;;
 	*-acorn)
@@ -1472,8 +1515,17 @@ case $basic_machine in
 	arm*-semi)
 		os=-aout
 		;;
-        c4x-* | tic4x-*)
-        	os=-coff
+	c4x-* | tic4x-*)
+		os=-coff
+		;;
+	tic54x-*)
+		os=-coff
+		;;
+	tic55x-*)
+		os=-coff
+		;;
+	tic6x-*)
+		os=-coff
 		;;
 	# This must come before the *-dec entry.
 	pdp10-*)
@@ -1500,7 +1552,7 @@ case $basic_machine in
 	m68*-cisco)
 		os=-aout
 		;;
-        mep-*)
+	mep-*)
 		os=-elf
 		;;
 	mips*-cisco)
@@ -1527,7 +1579,7 @@ case $basic_machine in
 	*-ibm)
 		os=-aix
 		;;
-    	*-knuth)
+	*-knuth)
 		os=-mmixware
 		;;
 	*-wec)
diff --git a/configure b/configure
index cd0c4cfce..857299d09 100755
--- a/configure
+++ b/configure
@@ -615,6 +615,8 @@ ac_includes_default="\
 ac_subst_vars='am__EXEEXT_FALSE
 am__EXEEXT_TRUE
 LTLIBOBJS
+PNG_ARM_NEON_FALSE
+PNG_ARM_NEON_TRUE
 binconfigs
 pkgconfigdir
 PNGLIB_RELEASE
@@ -661,6 +663,11 @@ build_os
 build_vendor
 build_cpu
 build
+am__fastdepCCAS_FALSE
+am__fastdepCCAS_TRUE
+CCASDEPMODE
+CCASFLAGS
+CCAS
 am__fastdepCC_FALSE
 am__fastdepCC_TRUE
 CCDEPMODE
@@ -756,6 +763,7 @@ enable_libtool_lock
 with_zlib_prefix
 with_pkgconfigdir
 with_binconfigs
+enable_arm_neon
 '
       ac_precious_vars='build_alias
 host_alias
@@ -765,6 +773,8 @@ CFLAGS
 LDFLAGS
 LIBS
 CPPFLAGS
+CCAS
+CCASFLAGS
 CPP'
 
 
@@ -1395,6 +1405,7 @@ Optional Features:
   --enable-fast-install[=PKGS]
                           optimize for fast installation [default=yes]
   --disable-libtool-lock  avoid locking (might break parallel builds)
+  --enable-arm-neon       Enable ARM NEON optmizations
 
 Optional Packages:
   --with-PACKAGE[=ARG]    use PACKAGE [ARG=yes]
@@ -1418,6 +1429,8 @@ Some influential environment variables:
   LIBS        libraries to pass to the linker, e.g. -l<library>
   CPPFLAGS    (Objective) C/C++ preprocessor flags, e.g. -I<include dir> if
               you have headers in a nonstandard directory <include dir>
+  CCAS        assembler compiler command (defaults to CC)
+  CCASFLAGS   assembler compiler flags (defaults to CFLAGS)
   CPP         C preprocessor
 
 Use these variables to override the choices made by `configure' or to help
@@ -3784,6 +3797,138 @@ else
 fi
 
 
+# By default we simply use the C compiler to build assembly code.
+
+test "${CCAS+set}" = set || CCAS=$CC
+test "${CCASFLAGS+set}" = set || CCASFLAGS=$CFLAGS
+
+
+
+depcc="$CCAS"   am_compiler_list=
+
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking dependency style of $depcc" >&5
+$as_echo_n "checking dependency style of $depcc... " >&6; }
+if ${am_cv_CCAS_dependencies_compiler_type+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  if test -z "$AMDEP_TRUE" && test -f "$am_depcomp"; then
+  # We make a subdir and do the tests there.  Otherwise we can end up
+  # making bogus files that we don't know about and never remove.  For
+  # instance it was reported that on HP-UX the gcc test will end up
+  # making a dummy file named `D' -- because `-MD' means `put the output
+  # in D'.
+  mkdir conftest.dir
+  # Copy depcomp to subdir because otherwise we won't find it if we're
+  # using a relative directory.
+  cp "$am_depcomp" conftest.dir
+  cd conftest.dir
+  # We will build objects and dependencies in a subdirectory because
+  # it helps to detect inapplicable dependency modes.  For instance
+  # both Tru64's cc and ICC support -MD to output dependencies as a
+  # side effect of compilation, but ICC will put the dependencies in
+  # the current directory while Tru64 will put them in the object
+  # directory.
+  mkdir sub
+
+  am_cv_CCAS_dependencies_compiler_type=none
+  if test "$am_compiler_list" = ""; then
+     am_compiler_list=`sed -n 's/^#*\([a-zA-Z0-9]*\))$/\1/p' < ./depcomp`
+  fi
+  am__universal=false
+
+
+  for depmode in $am_compiler_list; do
+    # Setup a source with many dependencies, because some compilers
+    # like to wrap large dependency lists on column 80 (with \), and
+    # we should not choose a depcomp mode which is confused by this.
+    #
+    # We need to recreate these files for each test, as the compiler may
+    # overwrite some of them when testing with obscure command lines.
+    # This happens at least with the AIX C compiler.
+    : > sub/conftest.c
+    for i in 1 2 3 4 5 6; do
+      echo '#include "conftst'$i'.h"' >> sub/conftest.c
+      # Using `: > sub/conftst$i.h' creates only sub/conftst1.h with
+      # Solaris 8's {/usr,}/bin/sh.
+      touch sub/conftst$i.h
+    done
+    echo "${am__include} ${am__quote}sub/conftest.Po${am__quote}" > confmf
+
+    # We check with `-c' and `-o' for the sake of the "dashmstdout"
+    # mode.  It turns out that the SunPro C++ compiler does not properly
+    # handle `-M -o', and we need to detect this.  Also, some Intel
+    # versions had trouble with output in subdirs
+    am__obj=sub/conftest.${OBJEXT-o}
+    am__minus_obj="-o $am__obj"
+    case $depmode in
+    gcc)
+      # This depmode causes a compiler race in universal mode.
+      test "$am__universal" = false || continue
+      ;;
+    nosideeffect)
+      # after this tag, mechanisms are not by side-effect, so they'll
+      # only be used when explicitly requested
+      if test "x$enable_dependency_tracking" = xyes; then
+	continue
+      else
+	break
+      fi
+      ;;
+    msvisualcpp | msvcmsys)
+      # This compiler won't grok `-c -o', but also, the minuso test has
+      # not run yet.  These depmodes are late enough in the game, and
+      # so weak that their functioning should not be impacted.
+      am__obj=conftest.${OBJEXT-o}
+      am__minus_obj=
+      ;;
+    none) break ;;
+    esac
+    if depmode=$depmode \
+       source=sub/conftest.c object=$am__obj \
+       depfile=sub/conftest.Po tmpdepfile=sub/conftest.TPo \
+       $SHELL ./depcomp $depcc -c $am__minus_obj sub/conftest.c \
+         >/dev/null 2>conftest.err &&
+       grep sub/conftst1.h sub/conftest.Po > /dev/null 2>&1 &&
+       grep sub/conftst6.h sub/conftest.Po > /dev/null 2>&1 &&
+       grep $am__obj sub/conftest.Po > /dev/null 2>&1 &&
+       ${MAKE-make} -s -f confmf > /dev/null 2>&1; then
+      # icc doesn't choke on unknown options, it will just issue warnings
+      # or remarks (even with -Werror).  So we grep stderr for any message
+      # that says an option was ignored or not supported.
+      # When given -MP, icc 7.0 and 7.1 complain thusly:
+      #   icc: Command line warning: ignoring option '-M'; no argument required
+      # The diagnosis changed in icc 8.0:
+      #   icc: Command line remark: option '-MP' not supported
+      if (grep 'ignoring option' conftest.err ||
+          grep 'not supported' conftest.err) >/dev/null 2>&1; then :; else
+        am_cv_CCAS_dependencies_compiler_type=$depmode
+        break
+      fi
+    fi
+  done
+
+  cd ..
+  rm -rf conftest.dir
+else
+  am_cv_CCAS_dependencies_compiler_type=none
+fi
+
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $am_cv_CCAS_dependencies_compiler_type" >&5
+$as_echo "$am_cv_CCAS_dependencies_compiler_type" >&6; }
+CCASDEPMODE=depmode=$am_cv_CCAS_dependencies_compiler_type
+
+ if
+  test "x$enable_dependency_tracking" != xno \
+  && test "$am_cv_CCAS_dependencies_compiler_type" = gcc3; then
+  am__fastdepCCAS_TRUE=
+  am__fastdepCCAS_FALSE='#'
+else
+  am__fastdepCCAS_TRUE='#'
+  am__fastdepCCAS_FALSE=
+fi
+
+
 # Make sure we can run config.sub.
 $SHELL "$ac_aux_dir/config.sub" sun4 >/dev/null 2>&1 ||
   as_fn_error $? "cannot run $SHELL $ac_aux_dir/config.sub" "$LINENO" 5
@@ -10625,7 +10770,14 @@ freebsd* | dragonfly*)
     *) objformat=elf ;;
     esac
   fi
-  version_type=freebsd-$objformat
+  # Handle Gentoo/FreeBSD as it was Linux
+  case $host_vendor in
+    gentoo)
+      version_type=linux ;;
+    *)
+      version_type=freebsd-$objformat ;;
+  esac
+
   case $version_type in
     freebsd-elf*)
       library_names_spec='${libname}${release}${shared_ext}$versuffix ${libname}${release}${shared_ext} $libname${shared_ext}'
@@ -10636,6 +10788,12 @@ freebsd* | dragonfly*)
       library_names_spec='${libname}${release}${shared_ext}$versuffix $libname${shared_ext}$versuffix'
       need_version=yes
       ;;
+    linux)
+      library_names_spec='${libname}${release}${shared_ext}$versuffix ${libname}${release}${shared_ext}$major ${libname}${shared_ext}'
+      soname_spec='${libname}${release}${shared_ext}$major'
+      need_lib_prefix=no
+      need_version=no
+      ;;
   esac
   shlibpath_var=LD_LIBRARY_PATH
   case $host_os in
@@ -12521,6 +12679,27 @@ fi
 
 
 
+# Check whether --enable-arm-neon was given.
+if test "${enable_arm_neon+set}" = set; then :
+  enableval=$enable_arm_neon; if test "${enableval}" = yes; then
+
+$as_echo "#define PNG_ARM_NEON 1" >>confdefs.h
+
+
+$as_echo "#define PNG_ALIGNED_MEMORY_SUPPORTED 1" >>confdefs.h
+
+	fi
+fi
+
+ if test "${enable_arm_neon:-no}" = yes; then
+  PNG_ARM_NEON_TRUE=
+  PNG_ARM_NEON_FALSE='#'
+else
+  PNG_ARM_NEON_TRUE='#'
+  PNG_ARM_NEON_FALSE=
+fi
+
+
 # Config files, substituting as above
 ac_config_files="$ac_config_files Makefile libpng.pc:libpng.pc.in"
 
@@ -12656,6 +12835,10 @@ if test -z "${am__fastdepCC_TRUE}" && test -z "${am__fastdepCC_FALSE}"; then
   as_fn_error $? "conditional \"am__fastdepCC\" was never defined.
 Usually this means the macro was only invoked conditionally." "$LINENO" 5
 fi
+if test -z "${am__fastdepCCAS_TRUE}" && test -z "${am__fastdepCCAS_FALSE}"; then
+  as_fn_error $? "conditional \"am__fastdepCCAS\" was never defined.
+Usually this means the macro was only invoked conditionally." "$LINENO" 5
+fi
 if test -z "${HAVE_SOLARIS_LD_TRUE}" && test -z "${HAVE_SOLARIS_LD_FALSE}"; then
   as_fn_error $? "conditional \"HAVE_SOLARIS_LD\" was never defined.
 Usually this means the macro was only invoked conditionally." "$LINENO" 5
@@ -12664,6 +12847,10 @@ if test -z "${HAVE_LD_VERSION_SCRIPT_TRUE}" && test -z "${HAVE_LD_VERSION_SCRIPT
   as_fn_error $? "conditional \"HAVE_LD_VERSION_SCRIPT\" was never defined.
 Usually this means the macro was only invoked conditionally." "$LINENO" 5
 fi
+if test -z "${PNG_ARM_NEON_TRUE}" && test -z "${PNG_ARM_NEON_FALSE}"; then
+  as_fn_error $? "conditional \"PNG_ARM_NEON\" was never defined.
+Usually this means the macro was only invoked conditionally." "$LINENO" 5
+fi
 
 : "${CONFIG_STATUS=./config.status}"
 ac_write_fail=0
diff --git a/configure.ac b/configure.ac
index f3db9f7d9..a31039033 100644
--- a/configure.ac
+++ b/configure.ac
@@ -36,6 +36,7 @@ AM_CONFIG_HEADER(config.h)
 # Checks for programs.
 AC_LANG([C])
 AC_PROG_CC
+AM_PROG_AS
 AC_PROG_LD
 AC_PROG_CPP
 AC_CHECK_TOOL(SED, sed, :)
@@ -177,6 +178,14 @@ AC_ARG_WITH(binconfigs,
 	[binconfigs='${binconfigs}'])
 AC_SUBST([binconfigs])
 
+AC_ARG_ENABLE([arm-neon],
+	AC_HELP_STRING([--enable-arm-neon], [Enable ARM NEON optmizations]),
+	[if test "${enableval}" = yes; then
+		AC_DEFINE([PNG_ARM_NEON], [1], [Enable ARM NEON optmizations])
+		AC_DEFINE([PNG_ALIGNED_MEMORY_SUPPORTED], [1], [Align row buffers])
+	fi])
+AM_CONDITIONAL([PNG_ARM_NEON], [test "${enable_arm_neon:-no}" = yes])
+
 # Config files, substituting as above
 AC_CONFIG_FILES([Makefile libpng.pc:libpng.pc.in])
 AC_CONFIG_FILES([libpng-config:libpng-config.in],