Merge from gnulib

* build-aux/config.guess: Copy from gnulib.
* lib/gnulib.mk.in: Regenerate.

build-aux/config.guess

@@ -2,7 +2,7 @@
 # Attempt to guess a canonical system name.
 #   Copyright 1992-2017 Free Software Foundation, Inc.
 
-timestamp='2017-05-11'
+timestamp='2017-05-27'
 
 # 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
@@ -1304,14 +1304,21 @@ EOF
 	if test `echo "$UNAME_RELEASE" | sed -e 's/\..*//'` -le 10 ; then
 	    if [ "$CC_FOR_BUILD" != no_compiler_found ]; then
 		if (echo '#ifdef __LP64__'; echo IS_64BIT_ARCH; echo '#endif') | \
-		    (CCOPTS="" $CC_FOR_BUILD -E - 2>/dev/null) | \
-		    grep IS_64BIT_ARCH >/dev/null
+		       (CCOPTS="" $CC_FOR_BUILD -E - 2>/dev/null) | \
+		       grep IS_64BIT_ARCH >/dev/null
 		then
 		    case $UNAME_PROCESSOR in
 			i386) UNAME_PROCESSOR=x86_64 ;;
 			powerpc) UNAME_PROCESSOR=powerpc64 ;;
 		    esac
 		fi
+		# On 10.4-10.6 one might compile for PowerPC via gcc -arch ppc
+		if (echo '#ifdef __POWERPC__'; echo IS_PPC; echo '#endif') | \
+		       (CCOPTS="" $CC_FOR_BUILD -E - 2>/dev/null) | \
+		       grep IS_PPC >/dev/null
+		then
+		    UNAME_PROCESSOR=powerpc
+		fi
 	    fi
 	elif test "$UNAME_PROCESSOR" = i386 ; then
 	    # Avoid executing cc on OS X 10.9, as it ships with a stub

lib/gnulib.mk.in

@@ -645,6 +645,8 @@ NS_OBJ = @NS_OBJ@
 NS_OBJC_OBJ = @NS_OBJC_OBJ@
 NTDIR = @NTDIR@
 NTLIB = @NTLIB@
+OBJC = @OBJC@
+OBJCFLAGS = @OBJCFLAGS@
 OBJEXT = @OBJEXT@
 OTHER_FILES = @OTHER_FILES@
 PACKAGE_BUGREPORT = @PACKAGE_BUGREPORT@
@@ -863,6 +865,7 @@ XRANDR_LIBS = @XRANDR_LIBS@
 XWIDGETS_OBJ = @XWIDGETS_OBJ@
 X_TOOLKIT_TYPE = @X_TOOLKIT_TYPE@
 ac_ct_CC = @ac_ct_CC@
+ac_ct_OBJC = @ac_ct_OBJC@
 archlibdir = @archlibdir@
 bindir = @bindir@
 bitmapdir = @bitmapdir@