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.
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 a CLFS system.
The Glibc build system is self-contained and will install perfectly, even though the compiler specs file and linker are still pointing at /tools. The specs and linker cannot be adjusted before the Glibc install because the Glibc Autoconf tests would give false results and defeat the goal of achieving a clean build.
The following patch fixes an issue that can cause localdef to segfault:
patch -Np1 -i ../glibc-2.4-localedef_segfault-1.patch
The following patch fixes an issue with iconv:
patch -Np1 -i ../glibc-2.4-iconv_fix-1.patch
The following sed fixes a build issue with Glibc. This will prevent nscd from trying to link to libraries that don't exist:
cp -v nscd/Makefile{,.orig} sed -e "/nscd_stat.o: sysincludes = # nothing/d" nscd/Makefile.orig > \ nscd/Makefile
The Glibc documentation recommends building Glibc outside of the source directory in a dedicated build directory:
mkdir -v ../glibc-build cd ../glibc-build
Tell Glibc to install its libraries into /lib:
echo "slibdir=/lib" >> configparms
Prepare Glibc for compilation:
../glibc-2.4/configure --prefix=/usr \ --disable-profile --enable-add-ons --enable-kernel=2.6.0 \ --libexecdir=/usr/lib/glibc --libdir=/usr/lib
The meaning of the new configure option:
This changes the location of the pt_chown program from its default of /usr/libexec to /usr/lib/glibc.
Compile the package:
make
The test suite for Glibc is considered critical. Do not skip it under any circumstance.
Test the results:
make -k check >glibc-check-log 2>&1 ; grep Error glibc-check-log
The Glibc test suite is highly dependent on certain functions of the host system, in particular the kernel. The posix/annexc test normally fails and you should see Error 1 (ignored) in the output. Apart from this, the Glibc test suite is always expected to pass. However, in certain circumstances, some failures are unavoidable. If a test fails because of a missing program (or missing symbolic link), or a segfault, you will see an error code greater than 127 and the details will be in the log. More commonly, tests will fail with Error 2 - for these, the contents of the corresponding .out file, e.g. posix/annexc.out may be informative. Here is a list of the most common issues:
The math tests sometimes fail. Certain optimization settings are known to be a factor here.
If you have mounted the CLFS partition with the noatime option, the atime test will fail. As mentioned in Section 2.4, “Mounting the New Partition”, do not use the noatime option while building CLFS.
When running on older and slower hardware, some tests can fail because of test timeouts being exceeded.
Though it is a harmless message, the install stage of Glibc will complain about the absence of /etc/ld.so.conf. Prevent this warning with:
touch /etc/ld.so.conf
The install will finish by checking that everything is correctly installed. Unfortunately, it will test for a multilib installation. On x86_64 Pure64 this means it will try to test the non-existent 32-bit loader which has a different name from the 64-bit loader (unlike on other 64-bit architectures). We fool it by creating a symlink to the real loader.
ln -sv ld-2.4.so /lib/ld-linux.so.2
Install the package:
make install
Now we can remove this symlink. We also need to correct the /usr/bin/ldd script - if you look at this, you will see it references not only the 32-bit linker, but also /lib64 where it thinks the 64-bit linker is. The following sed will correct this:
rm -v /lib/ld-linux.so.2 cp -v /usr/bin/ldd{,.bak} sed '/RTLDLIST/s%/ld-linux.so.2 /lib64%%' /usr/bin/ldd.bak >/usr/bin/ldd
Check the script to make sure the sed worked correctly, then delete the backup.
rm -v /usr/bin/ldd.bak
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-2.4/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 /usr/lib/locale localedef -i de_DE -f ISO-8859-1 de_DE localedef -i de_DE@euro -f ISO-8859-15 de_DE@euro localedef -i en_HK -f ISO-8859-1 en_HK localedef -i en_PH -f ISO-8859-1 en_PH localedef -i en_US -f ISO-8859-1 en_US localedef -i es_MX -f ISO-8859-1 es_MX localedef -i fa_IR -f UTF-8 fa_IR localedef -i fr_FR -f ISO-8859-1 fr_FR localedef -i fr_FR@euro -f ISO-8859-15 fr_FR@euro localedef -i it_IT -f ISO-8859-1 it_IT localedef -i ja_JP -f EUC-JP ja_JP
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 > /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:
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 /usr/share/zoneinfo/[xxx] \ /etc/localtime
Replace [xxx] with the name of the time zone that tzselect provided (e.g., Canada/Eastern).
The meaning of the cp option:
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.
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 > /etc/ld.so.conf << "EOF" # Begin /etc/ld.so.conf /usr/local/lib /opt/lib # End /etc/ld.so.conf EOF