* version.h (VERSION): 2.4 glibc-2.4 cvs/glibc-2_4 cvs/fedora-glibc-20060306T1239

	* README.template: Update for 2.4.
	* README: Regenerated.
	* manual/install.texi (Configuring and compiling): Separate build
	directory is mandatory.  Use glibc-2.4 in example.
	Update --enable-add-ons description.
	(Supported Configurations): Remove section.
	* INSTALL: Regenerated.

7 files changed, 252 insertions, 296 deletions

diff --git a/ChangeLog b/ChangeLog
index a588dd5468..1c85510b4d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,14 @@
 2006-03-06  Roland McGrath  <roland@redhat.com>
 
+	* version.h (VERSION): 2.4
+	* README.template: Update for 2.4.
+	* README: Regenerated.
+	* manual/install.texi (Configuring and compiling): Separate build
+	directory is mandatory.  Use glibc-2.4 in example.
+	Update --enable-add-ons description.
+	(Supported Configurations): Remove section.
+	* INSTALL: Regenerated.
+
 	* sysdeps/unix/sysv/linux/x86_64/sysconf.c
 	(handle_intel, handle_amd): Add __attribute__ ((noinline)).
 	* sysdeps/unix/sysv/linux/i386/sysconf.c
diff --git a/INSTALL b/INSTALL
index f60658f1ae..8d61b3e489 100644
--- a/INSTALL
+++ b/INSTALL
@@ -18,29 +18,28 @@ below.
 Configuring and compiling GNU Libc
 ==================================
 
-GNU libc can be compiled in the source directory, but we strongly advise
-building it in a separate build directory.  For example, if you have
-unpacked the glibc sources in `/src/gnu/glibc-2.3', create a directory
+GNU libc cannot be compiled in the source directory.  You must build it
+in a separate build directory.  For example, if you have unpacked the
+glibc sources in `/src/gnu/glibc-2.4', create a directory
 `/src/gnu/glibc-build' to put the object files in.  This allows
-removing the whole build directory in case an error occurs, which is the
-safest way to get a fresh start and should always be done.
+removing the whole build directory in case an error occurs, which is
+the safest way to get a fresh start and should always be done.
 
    From your object directory, run the shell script `configure' located
 at the top level of the source tree.  In the scenario above, you'd type
 
-     $ ../glibc-2.3/configure ARGS...
+     $ ../glibc-2.4/configure ARGS...
 
-   Please note that even if you're building in a separate build
+   Please note that even though you're building in a separate build
 directory, the compilation needs to modify a few files in the source
 directory, especially some files in the manual subdirectory.
 
-`configure' takes many options, but you can get away with knowing only
-two: `--prefix' and `--enable-add-ons'.  The `--prefix' option tells
-`configure' where you want glibc installed. This defaults to
-`/usr/local'.  The `--enable-add-ons' option tells `configure' to use
-all the add-on bundles it finds in the source directory.  Since
-important functionality is provided in add-ons, you should always
-specify this option.
+`configure' takes many options, but the only one that is usually
+mandatory is `--prefix'.  This option tells `configure' where you want
+glibc installed.  This defaults to `/usr/local', but the normal setting
+to install as the standard system library is `--prefix=/usr' for
+GNU/Linux systems and `--prefix=' (an empty prefix) for GNU/Hurd
+systems.
 
    It may also be useful to set the CC and CFLAGS variables in the
 environment when running `configure'.  CC selects the C compiler that
@@ -72,11 +71,16 @@ will be used, and CFLAGS sets optimization options for the compiler.
      ones found in `/usr/include'.
 
 `--enable-add-ons[=LIST]'
-     Enable add-on packages in your source tree.  If this option is
+     Specify add-on packages to include in the build.  If this option is
      specified with no list, it enables all the add-on packages it
-     finds.  If you do not wish to use some add-on packages that you
-     have present in your source tree, give this option a list of the
-     add-ons that you _do_ want used, like this: `--enable-add-ons=nptl'
+     finds in the main source directory; this is the default behavior.
+     You may specify an explicit list of add-ons to use in LIST,
+     separated by spaces or commas (if you use spaces, remember to
+     quote them from the shell).  Each add-on in LIST can be an
+     absolute directory name or can be a directory name relative to the
+     main source directory, or relative to the build directory (that
+     is, the current working directory).  For example,
+     `--enable-add-ons=nptl,../glibc-libidn-2.4'.
 
 `--enable-kernel=VERSION'
      This option is currently only useful on GNU/Linux systems.  The
@@ -159,11 +163,10 @@ produce a lot of output, some of which may look like errors from `make'
 but isn't.  Look for error messages from `make' containing `***'.
 Those indicate that something is seriously wrong.
 
-   The compilation process can take several hours.  Expect at least two
-hours for the default configuration on i586 for GNU/Linux.  For Hurd,
-times are much longer.  Some complex modules may take a very long time
-to compile, as much as several minutes on slower machines.  Do not
-panic if the compiler appears to hang.
+   The compilation process can take a long time, depending on the
+configuration and the speed of your machine.  Some complex modules may
+take a very long time to compile, as much as several minutes on slower
+machines.  Do not panic if the compiler appears to hang.
 
    If you want to run a parallel make, simply pass the `-j' option with
 an appropriate numeric parameter to `make'.  You need a recent GNU
@@ -359,78 +362,6 @@ and if you change any of the message translation files you will need
 You may also need these packages if you upgrade your source tree using
 patches, although we try to avoid this.
 
-Supported Configurations
-========================
-
-The GNU C Library currently supports configurations that match the
-following patterns:
-
-     alpha*-*-linux
-     arm-*-linux
-     cris-*-linux
-     hppa-*-linux
-     iX86-*-gnu
-     iX86-*-linux
-     ia64-*-linux
-     m68k-*-linux
-     mips*-*-linux
-     powerpc-*-linux
-     s390-*-linux
-     s390x-*-linux
-     sparc-*-linux
-     sparc64-*-linux
-     x86_64-*-linux
-
-   Former releases of this library (version 2.1 and/or 2.0) used to run
-on the following configurations:
-
-     arm-*-linuxaout
-     arm-*-none
-
-   Very early releases (version 1.09.1 and perhaps earlier versions)
-used to run on the following configurations:
-
-     alpha-dec-osf1
-     alpha-*-linuxecoff
-     iX86-*-bsd4.3
-     iX86-*-isc2.2
-     iX86-*-isc3.N
-     iX86-*-sco3.2
-     iX86-*-sco3.2v4
-     iX86-*-sysv
-     iX86-*-sysv4
-     iX86-force_cpu386-none
-     iX86-sequent-bsd
-     i960-nindy960-none
-     m68k-hp-bsd4.3
-     m68k-mvme135-none
-     m68k-mvme136-none
-     m68k-sony-newsos3
-     m68k-sony-newsos4
-     m68k-sun-sunos4.N
-     mips-dec-ultrix4.N
-     mips-sgi-irix4.N
-     sparc-sun-solaris2.N
-     sparc-sun-sunos4.N
-
-   Since no one has volunteered to test and fix these configurations,
-they are not supported at the moment.  They probably don't compile;
-they definitely don't work anymore.  Porting the library is not hard.
-If you are interested in doing a port, please contact the glibc
-maintainers.  Start at `http://www.gnu.org/software/libc/' and read the
-references there on how to go about getting involved and contacting the
-developers.
-
-   Valid cases of `iX86' include `i386', `i486', `i586', and `i686'.
-All of those configurations produce a library that can run on this
-processor and newer processors.  The GCC compiler by default generates
-code that's optimized for the machine it's configured for and will use
-the instructions available on that machine.  For example if your GCC is
-configured for `i686', gcc will optimize for `i686' and might issue
-some `i686' specific instructions.  To generate code for other models,
-you have to configure for that model and give GCC the appropriate
-`-march=' and `-mcpu=' compiler switches via CFLAGS.
-
 Specific advice for GNU/Linux systems
 =====================================
 
diff --git a/README b/README
index 36a2af9129..9b9616ccb6 100644
--- a/README
+++ b/README
@@ -1,49 +1,91 @@
-This directory contains the version 2.3.4 release of the GNU C Library.
-Many bugs have been fixed since the last release.
-Some bugs surely remain.
-
-As of this release, the GNU C library is known to run on the following
-configurations:
-
-		*-*-gnu			GNU Hurd
-		i[3456]86-*-linux-gnu	Linux-2.x on Intel
-		m68k-*-linux-gnu	Linux-2.x on Motorola 680x0
-		alpha*-*-linux-gnu	Linux-2.x on DEC Alpha
-		powerpc-*-linux-gnu     Linux and MkLinux on PowerPC systems
-		powerpc64-*-linux-gnu	Linux-2.4.19+ on 64-bit PowerPC systems
-		sparc-*-linux-gnu	Linux-2.x on SPARC
-		sparc64-*-linux-gnu	Linux-2.x on UltraSPARC 64-bit
-		arm-*-none		ARM standalone systems
-		arm-*-linux		Linux-2.x on ARM
-		arm-*-linuxaout		Linux-2.x on ARM using a.out binaries
-		mips*-*-linux-gnu	Linux-2.x on MIPS
-		ia64-*-linux-gnu	Linux-2.x on ia64
-		s390-*-linux-gnu	Linux-2.x on IBM S/390
-		s390x-*-linux-gnu	Linux-2.4+ on IBM S/390 64-bit
-		sh-*-linux-gnu		Linux-2.x on Super Hitachi
-		x86-64-*-linux-gnu	Linux-2.4+ on x86-64
-
-Past releases of this library ran on a variety of configurations that are
-no longer supported.  Porting the library is not hard.  If you are
-interested in doing a port, please contact the glibc maintainers;
-see http://www.gnu.org/software/libc/ for more information.
-
-There are some add-ons which can be used together with GNU libc.  They
-are designed in a way to ease the installation by integrating them in
-the libc source tree.  Simply get the add-ons you need and use the
---enable-add-ons option of the `configure' script to tell where the
-add-ons are found.  Please read the FAQ file for more details.
-
-See the file INSTALL to find out how to configure, build, install, and port
-the GNU C library.  You might also consider reading the WWW pages for the
-GNU libc at http://www.gnu.org/software/libc/libc.html.
-
-The GNU C Library is completely documented by the Texinfo manual found
-in the `manual/' subdirectory.  The manual is still being updated and
-contains some known errors and omissions; we regret that we do not
-have the resources to work on the manual as much as we would like.
-Please send comments on the manual to <bug-glibc-manual@gnu.org>, and
-not to the library bug-reporting address.
+This directory contains the version 2.4 release of the GNU C Library.
+
+The GNU C Library is the standard system C library for all GNU systems,
+and is an important part of what makes up a GNU system.  It provides the
+system API for all programs written in C and C-compatible languages such
+as C++ and Objective C; the runtime facilities of other programming
+languages use the C library to access the underlying operating system.
+
+In GNU/Linux systems, the C library works with the Linux kernel to
+implement the operating system behavior seen by user applications.
+In GNU/Hurd systems, it works with a microkernel and Hurd servers.
+
+Version 2.4 is the first release after a long period of development, and
+introduces changes to the API and a new ABI for all configurations.  It
+has been tested and deployed in new production systems, but should still
+be considered somewhat experimental.  The stable 2.3 release series
+continues to be maintained, and implements a widely-deployed ABI.
+Version 2.3.6 is available, and we will release 2.3.7 with more bug fixes.
+
+The GNU C Library implements much of the POSIX.1 functionality in the
+GNU/Hurd system, using configurations i[34567]86-*-gnu.
+
+When working with Linux kernels, the GNU C Library version 2.4 is
+intended primarily for use with Linux kernel version 2.6.0 and later.
+We only support using the NPTL implementation of pthreads, which is now
+the default configuration.  Most of the C library will continue to work
+on older Linux kernels and many programs will not require a 2.6 kernel
+to run correctly.  However, pthreads and related functionality will not
+work at all on old kernels and we do not recommend using glibc 2.4 with
+any Linux kernel prior to 2.6.
+
+All Linux kernel versions prior to 2.6.16 are known to have some bugs that
+may cause some of the tests related to pthreads in "make check" to fail.
+If you see such problems, please try the test suite on the most recent
+Linux kernel version that you can use, before pursuing those bugs further.
+
+The old LinuxThreads add-on implementation of pthreads for older Linux
+kernels is no longer supported, and we are not distributing it with this
+release.  Someone has volunteered to revive its maintenance unofficially
+for at least a short time for the benefit of those using Linux kernels
+older than 2.6, but a working version is not presently available.  When
+it is in working condition, we will make it available alongside future
+glibc releases.  LinuxThreads will not be supported.
+
+The GNU C Library supports these configurations for using Linux kernels:
+
+	i[34567]86-*-linux-gnu
+	x86_64-*-linux-gnu
+	powerpc-*-linux-gnu
+	powerpc64-*-linux-gnu
+	s390-*-linux-gnu
+	s390x-*-linux-gnu
+	ia64-*-linux-gnu
+	sparc*-*-linux-gnu
+	sparc64*-*-linux-gnu
+
+	alpha*-*-linux-gnu	Requires Linux 2.6.9 for NPTL
+	sh[34]-*-linux-gnu	Requires Linux 2.6.11
+
+The code for other CPU configurations supported by volunteers outside of
+the core glibc maintenance effort is contained in the separate `ports'
+add-on.  You can find glibc-ports-2.4 distributed separately in the
+same place where you got the main glibc distribution files.
+Currently these configurations are known to work using the `ports' add-on:
+
+	arm-*-linux-gnu		Requires Linux 2.6.15 for NPTL, no SMP support
+	arm-*-linux-gnueabi	Requires Linux 2.6.16-rc1 for NPTL, no SMP
+	mips-*-linux-gnu	Requires Linux 2.6.12 for NPTL
+	mips64-*-linux-gnu	Requires Linux 2.6.12 for NPTL
+
+The ports distribution also contains code for other configurations that
+do not work or have not been maintained recently, but will be of use to
+anyone trying to make a new configuration work.  If you are interested
+in doing a port, please contact the glibc maintainers; see
+http://www.gnu.org/software/libc/ for more information.
+
+See the file INSTALL to find out how to configure, build, and install
+the GNU C Library.  You might also consider reading the WWW pages for
+the C library at http://www.gnu.org/software/libc/.
+
+The GNU C Library is (almost) completely documented by the Texinfo manual
+found in the `manual/' subdirectory.  The manual is still being updated
+and contains some known errors and omissions; we regret that we do not
+have the resources to work on the manual as much as we would like.  For
+corrections to the manual, please file a bug in the `manual' component,
+following the bug-reporting instructions below.  Please be sure to check
+the manual in the current development sources to see if your problem has
+already been corrected.
 
 The file NOTES contains a description of the feature-test macros used
 in the GNU C library, explaining how you can tell the library what
diff --git a/README.template b/README.template
index d501d718df..5e22a270b5 100644
--- a/README.template
+++ b/README.template
@@ -1,49 +1,91 @@
 This directory contains the version VERSION release of the GNU C Library.
-Many bugs have been fixed since the last release.
-Some bugs surely remain.
-
-As of this release, the GNU C library is known to run on the following
-configurations:
-
-		*-*-gnu			GNU Hurd
-		i[3456]86-*-linux-gnu	Linux-2.x on Intel
-		m68k-*-linux-gnu	Linux-2.x on Motorola 680x0
-		alpha*-*-linux-gnu	Linux-2.x on DEC Alpha
-		powerpc-*-linux-gnu     Linux and MkLinux on PowerPC systems
-		powerpc64-*-linux-gnu	Linux-2.4.19+ on 64-bit PowerPC systems
-		sparc-*-linux-gnu	Linux-2.x on SPARC
-		sparc64-*-linux-gnu	Linux-2.x on UltraSPARC 64-bit
-		arm-*-none		ARM standalone systems
-		arm-*-linux		Linux-2.x on ARM
-		arm-*-linuxaout		Linux-2.x on ARM using a.out binaries
-		mips*-*-linux-gnu	Linux-2.x on MIPS
-		ia64-*-linux-gnu	Linux-2.x on ia64
-		s390-*-linux-gnu	Linux-2.x on IBM S/390
-		s390x-*-linux-gnu	Linux-2.4+ on IBM S/390 64-bit
-		sh-*-linux-gnu		Linux-2.x on Super Hitachi
-		x86-64-*-linux-gnu	Linux-2.4+ on x86-64
-
-Past releases of this library ran on a variety of configurations that are
-no longer supported.  Porting the library is not hard.  If you are
-interested in doing a port, please contact the glibc maintainers;
-see http://www.gnu.org/software/libc/ for more information.
-
-There are some add-ons which can be used together with GNU libc.  They
-are designed in a way to ease the installation by integrating them in
-the libc source tree.  Simply get the add-ons you need and use the
---enable-add-ons option of the `configure' script to tell where the
-add-ons are found.  Please read the FAQ file for more details.
-
-See the file INSTALL to find out how to configure, build, install, and port
-the GNU C library.  You might also consider reading the WWW pages for the
-GNU libc at http://www.gnu.org/software/libc/libc.html.
-
-The GNU C Library is completely documented by the Texinfo manual found
-in the `manual/' subdirectory.  The manual is still being updated and
-contains some known errors and omissions; we regret that we do not
-have the resources to work on the manual as much as we would like.
-Please send comments on the manual to <bug-glibc-manual@gnu.org>, and
-not to the library bug-reporting address.
+
+The GNU C Library is the standard system C library for all GNU systems,
+and is an important part of what makes up a GNU system.  It provides the
+system API for all programs written in C and C-compatible languages such
+as C++ and Objective C; the runtime facilities of other programming
+languages use the C library to access the underlying operating system.
+
+In GNU/Linux systems, the C library works with the Linux kernel to
+implement the operating system behavior seen by user applications.
+In GNU/Hurd systems, it works with a microkernel and Hurd servers.
+
+Version 2.4 is the first release after a long period of development, and
+introduces changes to the API and a new ABI for all configurations.  It
+has been tested and deployed in new production systems, but should still
+be considered somewhat experimental.  The stable 2.3 release series
+continues to be maintained, and implements a widely-deployed ABI.
+Version 2.3.6 is available, and we will release 2.3.7 with more bug fixes.
+
+The GNU C Library implements much of the POSIX.1 functionality in the
+GNU/Hurd system, using configurations i[34567]86-*-gnu.
+
+When working with Linux kernels, the GNU C Library version 2.4 is
+intended primarily for use with Linux kernel version 2.6.0 and later.
+We only support using the NPTL implementation of pthreads, which is now
+the default configuration.  Most of the C library will continue to work
+on older Linux kernels and many programs will not require a 2.6 kernel
+to run correctly.  However, pthreads and related functionality will not
+work at all on old kernels and we do not recommend using glibc 2.4 with
+any Linux kernel prior to 2.6.
+
+All Linux kernel versions prior to 2.6.16 are known to have some bugs that
+may cause some of the tests related to pthreads in "make check" to fail.
+If you see such problems, please try the test suite on the most recent
+Linux kernel version that you can use, before pursuing those bugs further.
+
+The old LinuxThreads add-on implementation of pthreads for older Linux
+kernels is no longer supported, and we are not distributing it with this
+release.  Someone has volunteered to revive its maintenance unofficially
+for at least a short time for the benefit of those using Linux kernels
+older than 2.6, but a working version is not presently available.  When
+it is in working condition, we will make it available alongside future
+glibc releases.  LinuxThreads will not be supported.
+
+The GNU C Library supports these configurations for using Linux kernels:
+
+	i[34567]86-*-linux-gnu
+	x86_64-*-linux-gnu
+	powerpc-*-linux-gnu
+	powerpc64-*-linux-gnu
+	s390-*-linux-gnu
+	s390x-*-linux-gnu
+	ia64-*-linux-gnu
+	sparc*-*-linux-gnu
+	sparc64*-*-linux-gnu
+
+	alpha*-*-linux-gnu	Requires Linux 2.6.9 for NPTL
+	sh[34]-*-linux-gnu	Requires Linux 2.6.11
+
+The code for other CPU configurations supported by volunteers outside of
+the core glibc maintenance effort is contained in the separate `ports'
+add-on.  You can find glibc-ports-VERSION distributed separately in the
+same place where you got the main glibc distribution files.
+Currently these configurations are known to work using the `ports' add-on:
+
+	arm-*-linux-gnu		Requires Linux 2.6.15 for NPTL, no SMP support
+	arm-*-linux-gnueabi	Requires Linux 2.6.16-rc1 for NPTL, no SMP
+	mips-*-linux-gnu	Requires Linux 2.6.12 for NPTL
+	mips64-*-linux-gnu	Requires Linux 2.6.12 for NPTL
+
+The ports distribution also contains code for other configurations that
+do not work or have not been maintained recently, but will be of use to
+anyone trying to make a new configuration work.  If you are interested
+in doing a port, please contact the glibc maintainers; see
+http://www.gnu.org/software/libc/ for more information.
+
+See the file INSTALL to find out how to configure, build, and install
+the GNU C Library.  You might also consider reading the WWW pages for
+the C library at http://www.gnu.org/software/libc/.
+
+The GNU C Library is (almost) completely documented by the Texinfo manual
+found in the `manual/' subdirectory.  The manual is still being updated
+and contains some known errors and omissions; we regret that we do not
+have the resources to work on the manual as much as we would like.  For
+corrections to the manual, please file a bug in the `manual' component,
+following the bug-reporting instructions below.  Please be sure to check
+the manual in the current development sources to see if your problem has
+already been corrected.
 
 The file NOTES contains a description of the feature-test macros used
 in the GNU C library, explaining how you can tell the library what
diff --git a/elf/ldconfig.c b/elf/ldconfig.c
index 52add4ff58..359fbdbf0e 100644
--- a/elf/ldconfig.c
+++ b/elf/ldconfig.c
@@ -693,7 +693,20 @@ search_dir (const struct dir_entry *entry)
 #endif
 	      !is_hwcap_platform (direntry->d_name)))
 	continue;
-      len = strlen (entry->path) + strlen (direntry->d_name);
+      len = strlen (direntry->d_name);
+      /* Skip temporary files created by the prelink program.  Files with
+	 names like these are never really DSOs we want to look at.  */
+      if (len >= sizeof (".#prelink#") - 1)
+	{
+	  if (strcmp (direntry->d_name + len - sizeof (".#prelink#") + 1,
+		      ".#prelink#") == 0)
+	    continue;
+	  if (len >= sizeof (".#prelink#.XXXXXX") - 1
+	      && memcmp (direntry->d_name + len - sizeof (".#prelink#.XXXXXX")
+			 + 1, ".#prelink#.", sizeof (".#prelink#.") - 1) == 0)
+	    continue;
+	}
+      len += strlen (entry->path);
       if (len > file_name_len)
 	{
 	  file_name_len = len + 1;
diff --git a/manual/install.texi b/manual/install.texi
index d9dace916b..0cd4d622de 100644
--- a/manual/install.texi
+++ b/manual/install.texi
@@ -24,7 +24,6 @@ GNU Make, and possibly others.  @xref{Tools for Compilation}, below.
 * Running make install::        How to install it once you've got it
  compiled.
 * Tools for Compilation::       You'll need these first.
-* Supported Configurations::    What it runs on, what it doesn't.
 * Linux::                       Specific advice for GNU/Linux systems.
 * Reporting Bugs::              So they'll get fixed.
 @end menu
@@ -34,34 +33,31 @@ GNU Make, and possibly others.  @xref{Tools for Compilation}, below.
 @cindex configuring
 @cindex compiling
 
-GNU libc can be compiled in the source directory, but we strongly advise
-building it in a separate build directory.  For example, if you have
- unpacked
-the glibc sources in @file{/src/gnu/glibc-2.3}, create a directory
+GNU libc cannot be compiled in the source directory.  You must build
+it in a separate build directory.  For example, if you have unpacked
+the glibc sources in @file{/src/gnu/glibc-2.4}, create a directory
 @file{/src/gnu/glibc-build} to put the object files in.  This allows
-removing the whole build directory in case an error occurs, which is the
-safest way to get a fresh start and should always be done.
+removing the whole build directory in case an error occurs, which is
+the safest way to get a fresh start and should always be done.
 
 From your object directory, run the shell script @file{configure} located
 at the top level of the source tree.  In the scenario above, you'd type
 
 @smallexample
-$ ../glibc-2.3/configure @var{args@dots{}}
+$ ../glibc-2.4/configure @var{args@dots{}}
 @end smallexample
 
-Please note that even if you're building in a separate build directory,
-the compilation needs to modify a few files in the source
+Please note that even though you're building in a separate build
+directory, the compilation needs to modify a few files in the source
 directory, especially some files in the manual subdirectory.
 
 @noindent
-@code{configure} takes many options, but you can get away with knowing
-only two: @samp{--prefix} and @samp{--enable-add-ons}.  The
-@code{--prefix} option tells @code{configure} where you want glibc
-installed. This defaults to @file{/usr/local}.  The
-@samp{--enable-add-ons} option tells @code{configure} to use all the
-add-on bundles it finds in the source directory.  Since important
-functionality is provided in add-ons, you should always specify this
-option.
+@code{configure} takes many options, but the only one that is usually
+mandatory is @samp{--prefix}.  This option tells @code{configure}
+where you want glibc installed.  This defaults to @file{/usr/local},
+but the normal setting to install as the standard system library is
+@samp{--prefix=/usr} for GNU/Linux systems and @samp{--prefix=} (an
+empty prefix) for GNU/Hurd systems.
 
 It may also be useful to set the @var{CC} and @var{CFLAGS} variables in
 the environment when running @code{configure}.  @var{CC} selects the C
@@ -95,11 +91,15 @@ compile glibc with a newer set of kernel headers than the ones found in
 @file{/usr/include}.
 
 @item --enable-add-ons[=@var{list}]
-Enable add-on packages in your source tree.  If this option is specified
-with no list, it enables all the add-on packages it finds.  If you do
-not wish to use some add-on packages that you have present in your source
-tree, give this option a list of the add-ons that you @emph{do} want
-used, like this: @samp{--enable-add-ons=nptl}
+Specify add-on packages to include in the build.  If this option is
+specified with no list, it enables all the add-on packages it finds in
+the main source directory; this is the default behavior.  You may
+specify an explicit list of add-ons to use in @var{list}, separated by
+spaces or commas (if you use spaces, remember to quote them from the
+shell).  Each add-on in @var{list} can be an absolute directory name
+or can be a directory name relative to the main source directory, or
+relative to the build directory (that is, the current working directory).
+For example, @samp{--enable-add-ons=nptl,../glibc-libidn-2.4}.
 
 @item --enable-kernel=@var{version}
 This option is currently only useful on GNU/Linux systems.  The
@@ -186,11 +186,10 @@ produce a lot of output, some of which may look like errors from
 @code{make} but isn't.  Look for error messages from @code{make}
 containing @samp{***}.  Those indicate that something is seriously wrong.
 
-The compilation process can take several hours.  Expect at least two
-hours for the default configuration on i586 for GNU/Linux.  For Hurd,
-times are much longer.  Some complex modules may take a very long time
-to compile, as much as several minutes on slower machines.  Do not
-panic if the compiler appears to hang.
+The compilation process can take a long time, depending on the
+configuration and the speed of your machine.  Some complex modules may
+take a very long time to compile, as much as several minutes on slower
+machines.  Do not panic if the compiler appears to hang.
 
 If you want to run a parallel make, simply pass the @samp{-j} option
 with an appropriate numeric parameter to @code{make}.  You need a recent
@@ -407,86 +406,6 @@ GNU @code{gettext} 0.10.36 or later
 You may also need these packages if you upgrade your source tree using
 patches, although we try to avoid this.
 
-@node Supported Configurations
-@appendixsec Supported Configurations
-@cindex configurations, all supported
-
-The GNU C Library currently supports configurations that match the
-following patterns:
-
-@smallexample
-alpha@var{*}-@var{*}-linux
-arm-@var{*}-linux
-cris-@var{*}-linux
-hppa-@var{*}-linux
-i@var{x}86-@var{*}-gnu
-i@var{x}86-@var{*}-linux
-ia64-@var{*}-linux
-m68k-@var{*}-linux
-mips@var{*}-@var{*}-linux
-powerpc-@var{*}-linux
-s390-@var{*}-linux
-s390x-@var{*}-linux
-sparc-@var{*}-linux
-sparc64-@var{*}-linux
-x86_64-@var{*}-linux
-@end smallexample
-
-Former releases of this library (version 2.1 and/or 2.0) used to run on
-the following configurations:
-
-@smallexample
-arm-@var{*}-linuxaout
-arm-@var{*}-none
-@end smallexample
-
-Very early releases (version 1.09.1 and perhaps earlier versions) used
-to run on the following configurations:
-
-@smallexample
-alpha-dec-osf1
-alpha-@var{*}-linuxecoff
-i@var{x}86-@var{*}-bsd4.3
-i@var{x}86-@var{*}-isc2.2
-i@var{x}86-@var{*}-isc3.@var{n}
-i@var{x}86-@var{*}-sco3.2
-i@var{x}86-@var{*}-sco3.2v4
-i@var{x}86-@var{*}-sysv
-i@var{x}86-@var{*}-sysv4
-i@var{x}86-force_cpu386-none
-i@var{x}86-sequent-bsd
-i960-nindy960-none
-m68k-hp-bsd4.3
-m68k-mvme135-none
-m68k-mvme136-none
-m68k-sony-newsos3
-m68k-sony-newsos4
-m68k-sun-sunos4.@var{n}
-mips-dec-ultrix4.@var{n}
-mips-sgi-irix4.@var{n}
-sparc-sun-solaris2.@var{n}
-sparc-sun-sunos4.@var{n}
-@end smallexample
-
-Since no one has volunteered to test and fix these configurations,
-they are not supported at the moment.  They probably don't compile;
-they definitely don't work anymore.  Porting the library is not hard.
-If you are interested in doing a port, please contact the glibc
-maintainers.  Start at @url{http://www.gnu.org/software/libc/} and
-read the references there on how to go about getting involved and
-contacting the developers.
-
-Valid cases of @samp{i@var{x}86} include @samp{i386}, @samp{i486},
-@samp{i586}, and @samp{i686}.  All of those configurations produce a
-library that can run on this processor and newer processors.  The GCC
-compiler by default generates code that's optimized for the machine it's
-configured for and will use the instructions available on that machine.
-For example if your GCC is configured for @samp{i686}, gcc will optimize
-for @samp{i686} and might issue some @samp{i686} specific instructions.
-To generate code for other models, you have to configure for that model
-and give GCC the appropriate @samp{-march=} and @samp{-mcpu=} compiler
-switches via @var{CFLAGS}.
-
 @node Linux
 @appendixsec Specific advice for GNU/Linux systems
 @cindex upgrading from libc5
diff --git a/version.h b/version.h
index 3eec34c09b..b25fae485e 100644
--- a/version.h
+++ b/version.h
@@ -1,4 +1,4 @@
 /* This file just defines the current version number of libc.  */
 
 #define RELEASE "development"
-#define VERSION "2.3.91"
+#define VERSION "2.4"