# Copyright (C) 1991-1999,2000 Free Software Foundation, Inc.
# This file is part of the GNU C Library.

# The GNU C Library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Library General Public License as
# published by the Free Software Foundation; either version 2 of the
# License, or (at your option) any later version.

# The GNU C Library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# Library General Public License for more details.

# You should have received a copy of the GNU Library General Public
# License along with the GNU C Library; see the file COPYING.LIB.  If not,
# write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
# Boston, MA 02111-1307, USA.

#
#	Makefile configuration options for the GNU C library.
#
ifneq (,)
This makefile requires GNU Make.
endif

all: # Make this the default goal

ifneq "$(origin +included-Makeconfig)" "file"

+included-Makeconfig := yes

ifdef subdir
.. := ../
endif

# If config.make exists, the source directory was configured,
# so don't try to be clever and find another directory to build in.
ifneq (,$(wildcard $(..)config.make))
ARCH =
machine =
else	# Not configured.
ifndef ARCH
ifdef machine
ARCH = $(machine)
endif # machine
endif # ARCH
endif # config.make

# Directory for object files and libc.a.  If this is not defined, the
# object files live in the subdirectories where their sources live, and
# libc.a lives in the parent directory (this probably doesn't work any
# more).
ifdef ARCH
ifeq ($(filter /%,$(ARCH)),)
objdir := $(..)$(ARCH)
else
objdir = $(ARCH)
endif
endif

# $(common-objdir) is the place to put objects and
# such that are not specific to a single subdir.
ifdef objdir
objpfx := $(patsubst %//,%/,$(objdir)/$(subdir)/)
common-objpfx = $(objdir)/
common-objdir = $(objdir)
else
objpfx :=
ifdef ..
common-objpfx = $(..)
common-objdir = ..
else
# This is a kludge.  make wizards might grok.
common-objpfx = sysdeps/../
common-objdir = .
endif
endif

# Root of the sysdeps tree.
sysdep_dir := $(..)sysdeps
export sysdep_dir := $(sysdep_dir)

# Get the values defined by options to `configure'.
include $(common-objpfx)config.make

# We have a special subdir for each binary format.
# For now, only ELF is fully supported.
ifeq ($(elf),yes)
binfmt-subdir = elf
else
# This is probably better than nothing.
binfmt-subdir = aout
endif

# Complete path to sysdep dirs.
export full-config-sysdirs := $(addprefix $(..),$(config-sysdirs))

# Run config.status to update config.make and config.h.  We don't show the
# dependence of config.h to Make, because it is only touched when it
# changes and so config.status would be run every time; the dependence of
# config.make should suffice to force regeneration and re-exec, and the new
# image will notice if config.h changed.
$(common-objpfx)config.make: $(common-objpfx)config.status \
			     $(..)config.make.in $(..)config.h.in
	cd $(<D); $(SHELL) $(<F)

# Find all the sysdeps configure fragments, to make sure we re-run
# configure when any of them changes.
$(common-objpfx)config.status: $(..)version.h $(..)configure \
			       $(foreach dir,$(full-config-sysdirs),\
					 $(wildcard \
					   $(dir)/Implies) \
					 $(patsubst %.in,%,\
						    $(firstword $(wildcard \
 $(addprefix $(dir)/,configure configure.in)))))
	@cd $(@D); if test -f $(@F); then exec $(SHELL) $(@F) --recheck; else \
	 echo The GNU C library has not been configured. >&2; \
	 echo Run \`configure\' to configure it before building. >&2; \
	 echo Try \`configure --help\' for more details. >&2; \
	 exit 1; fi

# We don't want CPPFLAGS to be exported to the command running configure.
unexport CPPFLAGS

# Get the user's configuration parameters.
ifneq ($(wildcard $(..)configparms),)
include $(..)configparms
endif
ifneq ($(objpfx),)
ifneq ($(wildcard $(common-objpfx)configparms),)
include $(common-objpfx)configparms
endif
endif

####
####	These are the configuration variables.  You can define values for
####	the variables below in the file `configparms'.
####	Do NOT edit this file.
####


# Set this to either `stdio' or `libio', to compile in either GNU stdio
# or GNU libio.
ifndef stdio
stdio = stdio
endif

# Common prefix for machine-independent installation directories.
ifeq ($(origin prefix),undefined) # ifndef would override explicit empty value.
prefix = /usr/local
endif

# Decide whether we shall build the programs or not.  We always do this
# unless the user tells us (in configparms) or we are building for a
# standalone target.
ifndef build-programs
ifneq ($(config-os),none)
build-programs=yes
else
build-programs=no
endif
endif

# Common prefix for machine-dependent installation directories.
ifeq ($(origin exec_prefix),undefined)
exec_prefix = $(prefix)
endif

# Where to install the library and object files.
ifndef libdir
libdir = $(exec_prefix)/lib
endif
inst_libdir = $(install_root)$(libdir)

# Where to install the shared library and dynamic linker.
ifndef slibdir
slibdir = $(exec_prefix)/lib
endif
inst_slibdir = $(install_root)$(slibdir)

# Prefix to put on files installed in $(libdir).  For libraries `libNAME.a',
# the prefix is spliced between `lib' and the name, so the linker switch
# `-l$(libprefix)NAME' finds the library; for other files the prefix is
# just prepended to the whole file name.
ifeq ($(origin libprefix),undefined)
libprefix =
endif

# Where to install the header files.
ifndef includedir
includedir = $(exec_prefix)/include
endif
inst_includedir = $(install_root)$(includedir)

# Where to install machine-independent data files.
# These are the timezone database, and the locale database.
ifndef datadir
datadir = $(prefix)/share
endif
inst_datadir = $(install_root)$(datadir)

# Where to install the timezone data files (which are machine-independent).
ifndef zonedir
zonedir = $(datadir)/zoneinfo
endif
inst_zonedir = $(install_root)$(zonedir)

# Where to install the locale files.
ifndef localedir
localedir = $(libdir)/locale
endif
inst_localedir = $(install_root)$(localedir)

# Where to install the message catalog data files (which are
# machine-independent).
ifndef msgcatdir
msgcatdir = $(datadir)/locale
endif
inst_msgcatdir = $(install_root)$(msgcatdir)

# Where to install the locale charmap source files.
ifndef i18ndir
i18ndir = $(datadir)/i18n
endif
inst_i18ndir = $(install_root)$(i18ndir)

# Where to install the shared object for charset transformation.
ifndef gconvdir
gconvdir = $(libdir)/gconv
endif
inst_gconvdir = $(install_root)$(gconvdir)

# Where to install programs.
ifndef bindir
bindir = $(exec_prefix)/bin
endif
inst_bindir = $(install_root)$(bindir)

# Where to install internal programs.
ifndef libexecdir
libexecdir = $(exec_prefix)/libexec
endif
inst_libexecdir = $(install_root)$(libexecdir)

# Where to install administrative programs.
ifndef rootsbindir
rootsbindir = $(exec_prefix)/sbin
endif
inst_rootsbindir = $(install_root)$(rootsbindir)

ifndef sbindir
sbindir = $(exec_prefix)/sbin
endif
inst_sbindir = $(install_root)$(sbindir)

# Where to install the Info files.
ifndef infodir
infodir = $(prefix)/info
endif
inst_infodir = $(install_root)$(infodir)

# Where to install default configuration files.  These include the local
# timezone specification and network data base files.
ifndef sysconfdir
sysconfdir = $(prefix)/etc
endif
inst_sysconfdir = $(install_root)$(sysconfdir)

# What timezone should be the installed default (e.g., US/Eastern).
# Run `make -C time echo-zonenames' to see a list of available zone names.
# The local timezone can be changed with `zic -l TIMEZONE' at any time.
ifndef localtime
localtime = Factory
endif

# Where to install the "localtime" timezone file; this is the file whose
# contents $(localtime) specifies.  If this is a relative pathname, it is
# relative to $(zonedir).  It is a good idea to put this somewhere
# other than there, so the zoneinfo directory contains only universal data,
# localizing the configuration data elsewhere.
ifndef localtime-file
localtime-file = $(sysconfdir)/localtime
inst_localtime-file = $(install_root)$(localtime-file)
endif

# What to use for leap second specifications in compiling the default
# timezone files.  Set this to `/dev/null' for no leap second handling as
# 1003.1 requires, or to `leapseconds' for proper leap second handling.
# Both zone flavors are always available as `posix/ZONE' and `right/ZONE'.
# This variable determines the default: if it's `/dev/null',
# ZONE==posix/ZONE; if it's `leapseconds', ZONE==right/ZONE.
ifndef leapseconds
leapseconds = /dev/null
endif

# What timezone's DST rules should be used when a POSIX-style TZ
# environment variable doesn't specify any rules.  For 1003.1 compliance
# this timezone must use rules that are as U.S. federal law defines DST.
# Run `make -C time echo-zonenames' to see a list of available zone names.
# This setting can be changed with `zic -p TIMEZONE' at any time.
# If you want POSIX.1 compatibility, use `America/New_York'.
ifndef posixrules
posixrules = America/New_York
endif

# Where to install the "posixrules" timezone file; this is file
# whose contents $(posixrules) specifies.  If this is a relative
# pathname, it is relative to $(zonedir).
ifndef posixrules-file
posixrules-file = posixrules
endif


# Directory where your system's native header files live.
# This is used on Unix systems to generate some GNU libc header files.
ifndef sysincludedir
sysincludedir = /usr/include
endif


# Commands to install files.
ifndef INSTALL_DATA
INSTALL_DATA = $(INSTALL) -m 644
endif
ifndef INSTALL_PROGRAM
INSTALL_PROGRAM = $(INSTALL)
endif
ifndef INSTALL
INSTALL = install
endif


# The name of the C compiler.
# If you've got GCC, and it works, use it.
ifeq ($(origin CC),default)
CC := gcc
endif

# The name of the C compiler to use for compilations of programs to run on
# the host that is building the library.  If you set CC to a
# cross-compiler, you must set this to the normal compiler.
ifndef BUILD_CC
BUILD_CC = $(CC)
endif

# Default flags to pass the C compiler.
ifndef default_cflags
default_cflags := -g -O
endif

# Flags to pass the C compiler when assembling preprocessed assembly code
# (`.S' files).  On some systems the assembler doesn't understand the `#' line
# directives the preprocessor produces.  If you have troubling compiling
# assembly code, try using -P here to suppress these directives.
ifndef asm-CPPFLAGS
asm-CPPFLAGS =
endif

# ELF always supports init/fini sections
ifeq ($(elf),yes)
have-initfini = yes
endif

# Installed name of the startup code.
ifneq ($(have-initfini),yes)
# When not having init/fini, there is just one startfile, called crt0.o.
start-installed-name = crt0.o
else
# On systems having init/fini, crt0.o is called crt1.o, and there are
# some additional bizarre files.
start-installed-name = crt1.o
endif
# On systems that do not need a special startfile for statically linked
# binaries, simply set it to the normal name.
ifndef static-start-installed-name
static-start-installed-name = $(start-installed-name)
endif

# Command for linking programs with the C library.
ifndef +link
+link = $(CC) -nostdlib -nostartfiles -o $@ \
	      $(sysdep-LDFLAGS) $(config-LDFLAGS) $(LDFLAGS) $(LDFLAGS-$(@F)) \
	      $(addprefix $(csu-objpfx),$(start-installed-name)) \
	      $(+preinit) $(+prector) \
	      $(filter-out $(addprefix $(csu-objpfx),start.o \
						     $(start-installed-name))\
			   $(+preinit) $(link-extra-libs) \
			   $(common-objpfx)libc% $(+postinit),$^) \
	      $(link-extra-libs) $(link-libc) $(+postctor) $(+postinit)
endif
# Command for statically linking programs with the C library.
ifndef +link-static
+link-static = $(CC) -nostdlib -nostartfiles -static -o $@ \
	      $(sysdep-LDFLAGS) $(LDFLAGS)  \
	      $(addprefix $(csu-objpfx),$(static-start-installed-name)) \
	      $(+preinit) $(+prector) \
	      $(filter-out $(addprefix $(csu-objpfx),start.o \
						     $(start-installed-name))\
			   $(+preinit) $(link-extra-libs-static) \
			   $(common-objpfx)libc% $(+postinit),$^) \
	      $(link-extra-libs-static) $(link-libc-static) $(+postctor) $(+postinit)
endif
ifndef config-LDFLAGS
ifeq (yes,$(build-shared))
config-LDFLAGS = -Wl,-dynamic-linker=$(slibdir)/$(rtld-installed-name)
endif
endif
ifndef link-libc
ifeq (yes,$(build-shared))
# We need the versioned name of libc.so in the deps of $(others) et al
# so that the symlink to libc.so is created before anything tries to
# run the linked programs.
link-libc = -Wl,-rpath-link=$(rpath-link) \
	    $(common-objpfx)libc.so$(libc.so-version) \
	    $(common-objpfx)$(patsubst %,$(libtype.oS),c) $(gnulib)
# This is how to find at build-time things that will be installed there.
rpath-dirs = math elf dlfcn nss nis rt resolv crypt
rpath-link = \
$(common-objdir):$(subst $(empty) ,:,$(patsubst ../$(subdir),.,$(rpath-dirs:%=$(common-objpfx)%)))
elfobjdir := $(patsubst ../$(subdir),.,$(common-objpfx)elf)
else
nssobjdir := $(patsubst ../$(subdir),.,$(common-objpfx)nss)
resolvobjdir := $(patsubst ../$(subdir),.,$(common-objpfx)resolv)
link-libc = $(common-objpfx)libc.a $(otherlibs) $(gnulib) $(common-objpfx)libc.a $(gnulib)
endif
endif

# Choose the default search path for the dynamic linker based on
# where we will install libraries.
ifneq ($(libdir),$(slibdir))
default-rpath = $(slibdir):$(libdir)
else
default-rpath = $(libdir)
endif

ifndef link-extra-libs
ifeq (yes,$(build-shared))
ifneq ($(common-objpfx),$(objpfx))
link-extra-libs = $(foreach lib,$(LDLIBS-$(@F)),\
	$(wildcard $(common-objpfx)$(lib).so$($(notdir $(lib)).so-version) \
		   $(objpfx)$(lib).so$($(notdir $(lib)).so-version)))
else
link-extra-libs = $(foreach lib,$(LDLIBS-$(@F)),$(common-objpfx)$(lib).so$($(notdir $(lib)).so-version))
endif
else
link-extra-libs = $(foreach lib,$(LDLIBS-$(@F)),$(common-objpfx)$(lib).a)
endif
endif

# The static libraries.
ifeq (yes,$(build-static))
link-libc-static = $(common-objpfx)libc.a $(gnulib) $(common-objpfx)libc.a
link-extra-libs-static = $(foreach lib,$(LDLIBS-$(@F)),$(common-objpfx)$(lib).a)
else
ifeq (yes,$(build-shared))
# We can try to link the programs with lib*_pic.a...
link-libc-static = $(gnulib) $(common-objpfx)libc_pic.a
link-extra-libs-static = $(link-extra-libs)
endif
endif

ifndef gnulib
gnulib := -lgcc
endif
ifeq ($(elf),yes)
+preinit = $(addprefix $(csu-objpfx),crti.o)
+postinit = $(addprefix $(csu-objpfx),crtn.o)
+prector = `$(CC) --print-file-name=crtbegin.o`
+postctor = `$(CC) --print-file-name=crtend.o`
+interp = $(addprefix $(elf-objpfx),interp.os)
endif
csu-objpfx = $(common-objpfx)csu/
elf-objpfx = $(common-objpfx)elf/

# How to run a program we just linked with our library.
# The program binary is assumed to be $(word 2,$^).
built-program-file = $(dir $(word 2,$^))$(notdir $(word 2,$^))
ifneq (yes,$(build-shared))
built-program-cmd = $(built-program-file)
else
comma = ,
sysdep-library-path = \
$(subst $(empty) ,:,$(strip $(patsubst -Wl$(comma)-rpath-link=%, %,\
				       $(filter -Wl$(comma)-rpath-link=%,\
						$(sysdep-LDFLAGS)))))
define built-program-cmd
$(elf-objpfx)$(rtld-installed-name) \
	--library-path $(rpath-link)$(patsubst %,:%,$(sysdep-library-path)) \
	$(built-program-file)
endef
endif

ifndef LD
LD := ld -X
endif

ifndef	RANLIB
RANLIB = ranlib
endif

# Extra flags to pass to GCC.
+gccwarn := -Wall -Wwrite-strings -Winline -Wstrict-prototypes

# This is the program that generates makefile
# dependencies from C source files.
ifndef +mkdep
+mkdep = $(CC) -M
endif

# The program that makes Emacs-style TAGS files.
ETAGS	:= etags -T

# The `m4' macro processor; this is used by sysdeps/sparc/Makefile (and
# perhaps others) to preprocess assembly code in some cases.
M4 = m4

# To force installation of files even if they are older than the
# installed files.  This variable is included in the dependency list
# of all installation targets.
ifeq ($(force-install),yes)
+force = force-install
else
+force =
endif

####
#### End of configuration variables.
####

# This tells some versions of GNU make before 3.63 not to export all variables.
.NOEXPORT:

# We want to echo the commands we're running without
# umpteen zillion filenames along with it (we use `...' instead)
# but we don't want this echoing done when the user has said
# he doesn't want to see commands echoed by using -s.
ifneq	"$(findstring s,$(MAKEFLAGS))" ""	# if -s
+cmdecho	:= echo >/dev/null
else						# not -s
+cmdecho	:= echo
endif	   					# -s

# These are the flags given to the compiler to tell
# it what sort of optimization and/or debugging output to do.
ifndef	+cflags
# If `CFLAGS' was defined, use that.
ifdef		CFLAGS
+cflags	:= $(filter-out -I%,$(CFLAGS))
endif		# CFLAGS
endif	# +cflags

# If none of the above worked, default to "-g -O".
ifeq	"$(strip $(+cflags))" ""
+cflags	:= $(default_cflags)
endif	# $(+cflags) == ""

+cflags := $(+cflags) $(+gccwarn)
+gcc-nowarn := -w

# Don't duplicate options if we inherited variables from the parent.
+cflags	:= $(sort $(+cflags))


# These are flags given to the C compiler to tell it to look for include
# files (including ones given in angle brackets) in the current directory,
# in the parent library source directory and in the include directory.
# `+sysdep-includes' will be defined by Makerules.
+includes = -I$(..)include -I. \
	    $(patsubst %/,-I%,$(objpfx)) $(patsubst %/,-I%,$(..)) \
	    $($(stdio)-include) $(includes) \
	    $(+sysdep-includes) $(last-includes) $(sysincludes)

# Since libio has several internal header files, we use a -I instead
# of many little headers in the include directory.
libio-include = -I$(..)libio

# These are the variables that the implicit compilation rules use.
CPPFLAGS = $($(subdir)-CPPFLAGS) $(+includes) $(defines) \
	   -include $(..)include/libc-symbols.h $(sysdep-CPPFLAGS) \
	   $(CPPFLAGS-$(suffix $@)) $(CPPFLAGS-$(<F)) $(CPPFLAGS-$(@F))
override CFLAGS	= $(filter-out %frame-pointer,$(+cflags)) $(sysdep-CFLAGS) \
		  $(CFLAGS-$(suffix $@)) $(CFLAGS-$(<F)) $(CFLAGS-$(@F))

# If everything is compiled with -fPIC (implicitly) we must tell this by
# defining the PIC symbol.
ifeq (yes,$(build-pic-default))
pic-default = -DPIC
endif

# Enable object files for different versions of the library.
# Various things use $(object-suffixes) to know what all to make.
# The compilation rules use $(CPPFLAGS-${SUFFIX}) and $(CFLAGS-${SUFFIX})
# to pass different flags for each flavor.
libtypes = $(foreach o,$(object-suffixes-for-libc),$(libtype$o))
all-object-suffixes := .o .os .op .og .ob .oS
object-suffixes :=
CPPFLAGS-.o = $(pic-default)
CFLAGS-.o = $(filter %frame-pointer,$(+cflags))
ifeq (yes,$(build-static))
libtype.o := lib%.a
object-suffixes += .o
endif
ifeq (yes,$(build-shared))
# Under --enable-shared, we will build a shared library of PIC objects.
# The PIC object files are named foo.os.
object-suffixes += .os
CPPFLAGS-.os = -DPIC
CFLAGS-.os = $(filter %frame-pointer,$(+cflags)) $(pic-ccflag)
libtype.os := lib%_pic.a
# This can be changed by a sysdep makefile
pic-ccflag = -fPIC
endif
ifeq (yes,$(build-profile))
# Under --enable-profile, we will build a static library of profiled objects.
# The profiled object files are named foo.op.
object-suffixes += .op
CPPFLAGS-.op = -DPROF $(pic-default)
CFLAGS-.op = -pg
libtype.op = lib%_p.a
endif
ifeq (yes,$(build-omitfp))
# Under --enable-omitfp, we build an the library optimized without
# debugging information using -fomit-frame-pointer, and build an extra
# library with debugging information.  The debuggable objects are named foo.og.
object-suffixes += .og
CPPFLAGS-.og = $(pic-default)
CFLAGS-.og = -g
CFLAGS-.o = $(filter %frame-pointer,$(+cflags)) -g0 -O99 -fomit-frame-pointer -D__USE_STRING_INLINES
CFLAGS-.os += -g0 -O99 -fomit-frame-pointer -D__USE_STRING_INLINES
libtype.og = lib%_g.a
endif
ifeq (yes,$(build-bounded))
# Under --enable-bounded, we build the library with `-fbounded-pointers -g'
# to runtime bounds checking.  The bounded-pointer objects are named foo.ob.
object-suffixes += .ob
CPPFLAGS-.ob = -DBOUNDED_POINTERS $(pic-default)
CFLAGS-.ob = -g -fbounded-pointers
libtype.ob = lib%_b.a
endif

object-suffixes-for-libc := $(object-suffixes)

ifeq (yes,$(build-shared))
# Build special library that contains the static-only routines for libc.
object-suffixes-for-libc += .oS

# Must build the routines as PIC, though, because they can end up in (users')
# shared objects.  We don't want to use CFLAGS-os because users may, for
# example, make that processor-specific.
CFLAGS-.oS = $(CFLAGS-.o) $(pic-ccflag)
CPPFLAGS-.oS = $(CPPFLAGS-.o) -DPIC
libtype.oS = lib%_nonshared.a
endif


+gnu-stabs = $(shell echo>&2 '*** BARF ON ME')

ifndef BUILD_CC
BUILD_CC = $(CC)
endif

move-if-change = $(SHELL) $(..)scripts/move-if-change

-include $(common-objpfx)sysd-dirs

ifeq ($(sysd-dirs-done),t)
-include $(common-objpfx)sysd-sorted
subdirs = $(sorted-subdirs)
endif

ifeq (yes, $(build-shared))

# Process the shlib-versions file, which tells us what shared library
# version numbers to use when we install shared objects on this system.
# We need to wait until $(subdirs) is complete.
ifeq ($(sysd-sorted-done),t)
-include $(common-objpfx)soversions.mk
ifndef avoid-generated
$(common-objpfx)soversions.i: $(..)shlib-versions $(..)Makeconfig \
			      $(wildcard $(patsubst %, $(..)%/shlib-versions,\
						       $(add-ons) \
						       $(subdirs))) \
			      $(common-objpfx)config.make
	sed -e 's/#.*$$//;s/^[ 	]*%/#/' \
	    $(filter-out $(..)Makeconfig $(common-objpfx)config.make,$^) \
	| $(CC) -E -undef -include $(common-objpfx)config.h -x c - \
	| while read conf version setname; do \
	    test -n "$$version" && \
	    test `expr '$(config-machine)-$(config-vendor)-$(config-os)' \
		       : "$$conf"` != 0 || continue; \
	    lib=`echo $$version | sed 's/=.*$$//'`; \
	    number=`echo $$version | sed "s/^.*=//"`; \
	    echo $$lib $$number $$setname; \
	  done > $@T; exit 0
	mv -f $@T $@
$(common-objpfx)soversions.mk: $(common-objpfx)soversions.i
	while read lib number setname; do \
	  case $$number in \
	    [0-9]*) echo "$$lib.so-version=.$$number"; \
		    echo "all-sonames+=$$lib.so\$$($$lib.so-version)";;\
	    *)	    echo "$$lib.so-version=$$number"; \
		    echo "all-sonames+=\$$($$lib.so-version)";;\
	  esac; \
	done < $< > $@T; exit 0
	mv -f $@T $@
endif
endif

postclean-generated += soversions.mk

# Generate the header containing the names of all shared libraries.
# We use a stamp file to avoid uncessary recompilations.
before-compile += $(common-objpfx)gnu/lib-names.h
$(common-objpfx)gnu/lib-names.h: $(common-objpfx)gnu/lib-names.stmp; @:
$(common-objpfx)gnu/lib-names.stmp: $(common-objpfx)soversions.mk
	$(make-target-directory)
	@rm -f ${@:stmp=T} $@
	(echo '/* This file is automatically generated.';\
	 echo '   It defines macros to allow user program to find the shared';\
	 echo '   library files which come as part of GNU libc.  */';\
	 echo '#ifndef __GNU_LIB_NAMES_H'; \
	 echo '#define __GNU_LIB_NAMES_H	1'; \
	 echo; \
	 (libs='$(all-sonames)';\
	  for l in $$libs; do \
	    upname=`echo $$l | sed 's/[.]so.*//' | \
		    tr 'abcdefghijklmnopqrstuvwxyz-' \
		       'ABCDEFGHIJKLMNOPQRSTUVWXYZ_'`; \
	    echo "#define	$${upname}_SO	\"$$l\""; \
	  done;) | sort; \
	 echo; \
	 echo '#endif	/* gnu/lib-names.h */';) > ${@:stmp=T}
	$(move-if-change) ${@:stmp=T} ${@:stmp=h}
	touch $@

common-generated += gnu/lib-names.h gnu/lib-names.stmp

# The name under which the run-time dynamic linker is installed.
# We are currently going for the convention that `/lib/ld.so.1'
# names the SVR4/ELF ABI-compliant dynamic linker.
ifndef rtld-installed-name
ifdef ld.so-version
rtld-installed-name = $(ld.so-version)
else
rtld-installed-name = ld.so.1
endif
endif

ifndef rtld-version-installed-name
rtld-version-installed-name = ld-$(version).so
endif

endif # build-shared

ifneq (,$(findstring linuxthreads,$(add-ons)))
shared-thread-library = $(common-objpfx)linuxthreads/libpthread.so
static-thread-library = $(common-objpfx)linuxthreads/libpthread.a
have-thread-library = yes
rpath-dirs += linuxthreads
endif

ifeq ($(elf),yes)
dlfcn = dlfcn
ifeq ($(build-shared),yes)
libdl = $(common-objpfx)dlfcn/libdl.so$(libdl.so-version)
else
libdl = $(common-objpfx)dlfcn/libdl.a
endif
else
# No ELF - no libdl, at least for now.
dlfcn =
libdl =
endif

# These are the subdirectories containing the library source.  The order
# is more or less arbitrary.  The sorting step will take care of the
# dependencies.  Only the $(binfmt-subdir) should always be kept at the
# end of the list.
all-subdirs = csu assert ctype locale intl catgets math setjmp signal	    \
	      stdlib stdio-common $(stdio) malloc string wcsmbs time dirent \
	      grp pwd posix io termios resource misc socket sysvipc gmon    \
	      gnulib iconv iconvdata wctype manual shadow po argp	    \
	      crypt $(add-ons) nss localedata timezone rt debug		    \
	      $(sysdep-subdirs) $(dlfcn) $(binfmt-subdir)
all-subdirs := $(filter-out $(sysdep-inhibit-subdirs),$(all-subdirs))

# The mach and hurd subdirectories have many generated header files which
# much of the rest of the library depends on, so it is best to build them
# first (and mach before hurd, at that).  The before-compile additions in
# sysdeps/{mach,hurd}/Makefile should make it reliably work for these files
# not to exist when making in other directories, but it will be slower that
# way with more somewhat expensive `make' invocations.
subdirs	:= $(filter mach,$(subdirs)) $(filter hurd,$(subdirs)) \
	   $(filter-out mach hurd,$(subdirs))

ifndef avoid-generated
all-Subdirs-files = $(wildcard $(config-sysdirs:%=$(..)%/Subdirs))
$(common-objpfx)sysd-dirs: $(common-objpfx)config.make $(all-Subdirs-files)
	$(AWK) 'BEGIN { subdirs = ""; inhibit = "" };			\
		/^#/ { next };						\
		/^[^-]/ { subdirs = subdirs " " $$0 };			\
		/^-/ { inhibit = inhibit " " substr($$0, 2) };		\
		END { printf "sysdep-subdirs =%s\n", subdirs;		\
		      printf "sysdep-inhibit-subdirs =%s\n", inhibit;	\
		      print "sysd-dirs-done = t" }'			\
	       $(patsubst $<,/dev/null,$^) > $@-tmp
	mv -f $@-tmp $@

all-Depend-files = $(wildcard $(..)*/Depend)
$(common-objpfx)sysd-sorted: $(..)scripts/gen-sorted.awk $(all-Depend-files) \
			     $(common-objpfx)sysd-dirs $(..)Makeconfig
	{ { dirs='$(patsubst $(..)%/Depend,$(..)%,$(filter %/Depend,$^))';\
	    for d in $$dirs; do						  \
	      while read on; do						  \
		echo "depend $$d $$on";					  \
	      done < $$d/Depend;					  \
	    done;							  \
	    for f in $(all-subdirs); do					  \
	      echo $$f;							  \
	    done;							  \
	  } | $(AWK) -f $< &&						  \
	  echo sysd-sorted-done = t;					  \
	} > $@-tmp
	mv -f $@-tmp $@
endif

endif # Makeconfig not yet included