5.8. Glibc-2.5
The Glibc package contains the main C library. This library
provides the basic routines for allocating memory, searching
directories, opening and closing files, reading and writing files,
string handling, pattern matching, arithmetic, and so on.
5.8.1. Installation of Glibc
![[Note]](../images/note.png)
Note
Some packages outside of CLFS suggest installing GNU libiconv
in order to translate data from one encoding to another. The
project's home page (http://www.gnu.org/software/libiconv/)
says “This library provides an
iconv() implementation, for use on
systems which don't have one, or whose implementation cannot
convert from/to Unicode.” Glibc provides an
iconv() implementation and can
convert from/to Unicode, therefore libiconv is not required on
an CLFS system.
The Glibc build will expect to find libgcc_eh, but this library is not installed when
GCC is built without "--enable-shared". As a result, the Glibc
build will fail. The following patch will force Glibc to check for
the existance of libgcc_eh and try to
link to it only if it exists:
patch -Np1 -i ../glibc-2.5-libgcc_eh-2.patch
The following patch fixes an issue that can cause
localdef to segfault:
patch -Np1 -i ../glibc-2.5-localedef_segfault-1.patch
The following patch builds zic-native,
localedef-native, and rpcgen-native. zic-native
is used to generate the zoneinfo, localedef-native is used to generate the locale
archive, and rpcgen-native is used to
generate part of librpcsvc.a. All of
these programs would normally not be available when
cross-compiling:
patch -Np1 -i ../glibc-2.5-cross_hacks-2.patch
The following patch corrects the Minor version, changing the value
from 4 to 5:
patch -Np1 -i ../glibc-2.5-MINOR-1.patch
The Glibc documentation recommends building Glibc outside of the
source directory in a dedicated build directory:
mkdir -v ../glibc-build
cd ../glibc-build
The following lines need to be added to config.cache for Glibc to support NPTL:
echo "libc_cv_forced_unwind=yes" > config.cache
echo "libc_cv_c_cleanup=yes" >> config.cache
The following line needs to be added to configparms to adjust installation paths:
echo "install_root=${CLFS}" > configparms
Prepare Glibc for compilation:
BUILD_CC="gcc" CC="${CLFS_TARGET}-gcc" \
AR="${CLFS_TARGET}-ar" RANLIB="${CLFS_TARGET}-ranlib" \
../glibc-2.5/configure --prefix=/usr --libexecdir=/usr/lib/glibc \
--host=${CLFS_TARGET} --build=${CLFS_HOST} \
--disable-profile --enable-add-ons \
--with-tls --enable-kernel=2.6.0 --with-__thread \
--with-binutils=${CLFS}/cross-tools/bin --with-headers=${CLFS}/usr/include \
--cache-file=config.cache
The meaning of the new configure options:
-
BUILD_CC="gcc"
-
This sets Glibc to use the current compiler on our system.
This is used to create the tools Glibc uses during its build.
-
CC="${CLFS_TARGET}-gcc"
-
This forces Glibc to use the GCC compiler that we made for
our target architecture.
-
AR="${CLFS_TARGET}-ar"
-
This forces Glibc to use the ar utility we made for our target
architecture.
-
RANLIB="${CLFS_TARGET}-ranlib"
-
This forces Glibc to use the ranlib utility we made for our
target architecture.
-
--disable-profile
-
This builds the libraries without profiling information. Omit
this option if profiling on the temporary tools is necessary.
-
--enable-add-ons
-
This tells Glibc to utilize all add-ons that are available.
-
--with-tls
-
This tells Glibc to use Thread Local Storage.
-
--with-__thread
-
This tells Glibc to use use the __thread for libc and
libpthread builds.
-
--with-binutils=${CLFS}/cross-tools/bin
-
This tells Glibc to use the Binutils that are specific to our
target architecture.
-
--cache-file=config.cache
-
This tells Glibc to utilize a premade cache file.
During this stage the following warning might appear:
configure: WARNING:
*** These auxiliary programs are missing or
*** incompatible versions: msgfmt
*** some features will be disabled.
*** Check the INSTALL file for required versions.
The missing or incompatible msgfmt program is generally harmless.
This msgfmt program
is part of the Gettext package which the host distribution should
provide.
Compile the package:
make
Install the package:
make install
5.8.2. Internationalization
The locales that can make the system respond in a different
language were not installed by the above command. Install them
with:
make localedata/install-locales
To save time, an alternative to running the previous command (which
generates and installs every locale listed in the
glibc-2.5/localedata/SUPPORTED file) is to install only those
locales that are wanted and needed. This can be achieved by using
the localedef
command. Information on this command is located in the INSTALL file in the Glibc source. However, there
are a number of locales that are essential in order for the tests
of future packages to pass, in particular, the libstdc++ tests from GCC. The following
instructions, instead of the install-locales target used above, will
install the minimum set of locales necessary for the tests to run
successfully:
mkdir -pv ${CLFS}/usr/lib/locale
export I18NPATH=${PWD}/localedata
export GCONV_PATH=${PWD}/iconvdata
export LOCALEDEF="${PWD}/locale/localedef-native --alias-file=../intl/locale.alias"
cd ../glibc-2.5/localedata
${LOCALEDEF} -i locales/de_DE -f charmaps/ISO-8859-1 --prefix=${CLFS} de_DE
${LOCALEDEF} -i locales/de_DE@euro -f charmaps/ISO-8859-15 --prefix=${CLFS} de_DE@euro
${LOCALEDEF} -i locales/en_HK -f charmaps/ISO-8859-1 --prefix=${CLFS} en_HK
${LOCALEDEF} -i locales/en_PH -f charmaps/ISO-8859-1 --prefix=${CLFS} en_PH
${LOCALEDEF} -i locales/en_US -f charmaps/ISO-8859-1 --prefix=${CLFS} en_US
${LOCALEDEF} -i locales/es_MX -f charmaps/ISO-8859-1 --prefix=${CLFS} es_MX
${LOCALEDEF} -i locales/fa_IR -f charmaps/UTF-8 --prefix=${CLFS} fa_IR
${LOCALEDEF} -i locales/fr_FR -f charmaps/ISO-8859-1 --prefix=${CLFS} fr_FR
${LOCALEDEF} -i locales/fr_FR@euro -f charmaps/ISO-8859-15 --prefix=${CLFS} fr_FR@euro
${LOCALEDEF} -i locales/it_IT -f charmaps/ISO-8859-1 --prefix=${CLFS} it_IT
${LOCALEDEF} -i locales/ja_JP -f charmaps/EUC-JP --prefix=${CLFS} ja_JP
unset I18NPATH GCONV_PATH LOCALEDEF
Some locales installed by the make
localedata/install-locales command above are not
properly supported by some applications that are in the CLFS and
BLFS books. Because of the various problems that arise due to
application programmers making assumptions that break in such
locales, CLFS should not be used in locales that utilize multibyte
character sets (including UTF-8) or right-to-left writing order.
Numerous unofficial and unstable patches are required to fix these
problems, and it has been decided by the CLFS developers not to
support such complex locales at this time. This applies to the
ja_JP and fa_IR locales as well—they have been installed only
for GCC and Gettext tests to pass, and the watch program (part of the Procps
package) does not work properly in them. Various attempts to
circumvent these restrictions are documented in
internationalization-related hints.
The /etc/nsswitch.conf file needs to be
created because, although Glibc provides defaults when this file is
missing or corrupt, the Glibc defaults do not work well in a
networked environment. The time zone also needs to be configured.
Create a new file /etc/nsswitch.conf by
running the following:
cat > ${CLFS}/etc/nsswitch.conf << "EOF"
# Begin /etc/nsswitch.conf
passwd: files
group: files
shadow: files
hosts: files dns
networks: files
protocols: files
services: files
ethers: files
rpc: files
# End /etc/nsswitch.conf
EOF
To determine the local time zone, run the following script:
TZDIR="${CLFS}/usr/share/zoneinfo" ${CLFS}/usr/bin/tzselect
After answering a few questions about the location, the script will
output the name of the time zone (e.g., EST5EDT or Canada/Eastern). Then create the
/etc/localtime file by running:
cp -v --remove-destination ${CLFS}/usr/share/zoneinfo/[xxx] \
${CLFS}/etc/localtime
Replace [xxx] with the name
of the time zone that tzselect provided (e.g., Canada/Eastern).
The meaning of the cp option:
-
--remove-destination
-
This is needed to force removal of the already existing
symbolic link. The reason for copying the file instead of
using a symlink is to cover the situation where /usr is on a separate partition. This could
be important when booted into single user mode.
5.8.4. Configuring The Dynamic Loader
By default, the dynamic loader (/lib/ld-linux.so.2) searches through /lib and /usr/lib for
dynamic libraries that are needed by programs as they are run.
However, if there are libraries in directories other than
/lib and /usr/lib, these need to be added to the /etc/ld.so.conf file in order for the dynamic
loader to find them. Two directories that are commonly known to
contain additional libraries are /usr/local/lib and /opt/lib, so add those directories to the dynamic
loader's search path.
Create a new file /etc/ld.so.conf by
running the following:
cat > ${CLFS}/etc/ld.so.conf << "EOF"
# Begin /etc/ld.so.conf
/usr/local/lib
/opt/lib
# End /etc/ld.so.conf
EOF
Installed
programs: catchsegv, gencat,
getconf, getent, iconv, iconvconfig, ldconfig, ldd, lddlibc4,
locale, localedef, mtrace, nscd, pcprofiledump, pt_chown,
rpcgen, rpcinfo, sln, sprof, tzselect, xtrace, zdump, and
zic
Installed
libraries: ld.so,
libBrokenLocale.[a,so], libSegFault.so, libanl.[a,so],
libbsd-compat.a, libc.[a,so], libcrypt.[a,so], libdl.[a,so],
libg.a, libieee.a, libm.[a,so], libmcheck.a, libmemusage.so,
libnsl.a, libnss_compat.so, libnss_dns.so, libnss_files.so,
libnss_hesiod.so, libnss_nis.so, libnss_nisplus.so,
libpcprofile.so, libpthread.[a,so], libresolv.[a,so],
librpcsvc.a, librt.[a,so], libthread_db.so, and
libutil.[a,so]
Short Descriptions
|
catchsegv
|
Can be used to create a stack trace when a program
terminates with a segmentation fault
|
|
gencat
|
Generates message catalogues
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|
getconf
|
Displays the system configuration values for file system
specific variables
|
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getent
|
Gets entries from an administrative database
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iconv
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Performs character set conversion
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|
iconvconfig
|
Creates fastloading iconv module configuration
files
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ldconfig
|
Configures the dynamic linker runtime bindings
|
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ldd
|
Reports which shared libraries are required by each given
program or shared library
|
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lddlibc4
|
Assists ldd
with object files
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locale
|
Tells the compiler to enable or disable the use of POSIX
locales for built-in operations
|
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localedef
|
Compiles locale specifications
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mtrace
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Reads and interprets a memory trace file and displays a
summary in human-readable format
|
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nscd
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A daemon that provides a cache for the most common name
service requests
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pcprofiledump
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Dumps information generated by PC profiling
|
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pt_chown
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A helper program for grantpt to set the owner, group
and access permissions of a slave pseudo terminal
|
|
rpcgen
|
Generates C code to implement the Remote Procecure Call
(RPC) protocol
|
|
rpcinfo
|
Makes an RPC call to an RPC server
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sln
|
A statically linked program that creates symbolic links
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sprof
|
Reads and displays shared object profiling data
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tzselect
|
Asks the user about the location of the system and
reports the corresponding time zone description
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|
xtrace
|
Traces the execution of a program by printing the
currently executed function
|
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zdump
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The time zone dumper
|
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zic
|
The time zone compiler
|
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ld.so
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The helper program for shared library executables
|
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libBrokenLocale
|
Used by programs, such as Mozilla, to solve broken
locales
|
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libSegFault
|
The segmentation fault signal handler
|
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libanl
|
An asynchronous name lookup library
|
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libbsd-compat
|
Provides the portability needed in order to run certain
Berkey Software Distribution (BSD) programs under Linux
|
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libc
|
The main C library
|
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libcrypt
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The cryptography library
|
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libdl
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The dynamic linking interface library
|
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libg
|
A runtime library for g++
|
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libieee
|
The Institute of Electrical and Electronic Engineers
(IEEE) floating point library
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libm
|
The mathematical library
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libmcheck
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Contains code run at boot
|
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libmemusage
|
Used by memusage (included in Glibc,
but not built in a base CLFS system as it has additional
dependencies) to help collect information about the
memory usage of a program
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libnsl
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The network services library
|
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libnss
|
The Name Service Switch libraries, containing functions
for resolving host names, user names, group names,
aliases, services, protocols, etc.
|
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libpcprofile
|
Contains profiling functions used to track the amount of
CPU time spent in specific source code lines
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libpthread
|
The POSIX threads library
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libresolv
|
Contains functions for creating, sending, and
interpreting packets to the Internet domain name servers
|
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librpcsvc
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Contains functions providing miscellaneous RPC services
|
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librt
|
Contains functions providing most of the interfaces
specified by the POSIX.1b Realtime Extension
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libthread_db
|
Contains functions useful for building debuggers for
multi-threaded programs
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libutil
|
Contains code for “standard” functions used in many
different Unix utilities
|