'--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
-will be used, and CFLAGS sets optimization options for the compiler.
+ It may also be useful to pass 'CC=COMPILER' and 'CFLAGS=FLAGS'
+arguments to 'configure'. 'CC' selects the C compiler that will be
+used, and 'CFLAGS' sets optimization options for the compiler. Any
+compiler options required for all compilations, such as options
+selecting an ABI or a processor for which to generate code, should be
+included in 'CC'. Options that may be overridden by the GNU C Library
+build system for particular files, such as for optimization and
+debugging, should go in 'CFLAGS'. The default value of 'CFLAGS' is '-g
+-O2', and the GNU C Library cannot be compiled without optimization, so
+if 'CFLAGS' is specified it must enable optimization. For example:
+
+ $ ../glibc-VERSION/configure CC="gcc -m32" CFLAGS="-O3"
The following list describes all of the available options for
'configure':
library will still be usable, but functionality may be lost--for
example, you can't build a shared libc with old binutils.
-'--without-fp'
- Use this option if your computer lacks hardware floating-point
- support and your operating system does not emulate an FPU.
+'--with-nonshared-cflags=CFLAGS'
+ Use additional compiler flags CFLAGS to build the parts of the
+ library which are always statically linked into applications and
+ libraries even with shared linking (that is, the object files
+ contained in 'lib*_nonshared.a' libraries). The build process will
+ automatically use the appropriate flags, but this option can be
+ used to set additional flags required for building applications and
+ libraries, to match local policy. For example, if such a policy
+ requires that all code linked into applications must be built with
+ source fortification,
+ '--with-nonshared-cflags=-Wp,-D_FORTIFY_SOURCE=2' will make sure
+ that the objects in 'libc_nonshared.a' are compiled with this flag
+ (although this will not affect the generated code in this
+ particular case and potentially change debugging information and
+ metadata only).
'--disable-shared'
Don't build shared libraries even if it is possible. Not all
systems support shared libraries; you need ELF support and
(currently) the GNU linker.
+'--enable-static-pie'
+ Enable static position independent executable (static PIE) support.
+ Static PIE is similar to static executable, but can be loaded at
+ any address without help from a dynamic linker. All static
+ programs as well as static tests are built as static PIE, except
+ for those marked with no-pie. The resulting glibc can be used with
+ the GCC option, -static-pie, which is available with GCC 8 or
+ above, to create static PIE. This option also implies that glibc
+ programs and tests are created as dynamic position independent
+ executables (PIE) by default.
+
+'--enable-cet'
+ Enable Intel Control-flow Enforcement Technology (CET) support.
+ When the GNU C Library is built with '--enable-cet', the resulting
+ library is protected with indirect branch tracking (IBT) and shadow
+ stack (SHSTK). When CET is enabled, the GNU C Library is
+ compatible with all existing executables and shared libraries.
+ This feature is currently supported on i386, x86_64 and x32 with
+ GCC 8 and binutils 2.29 or later. Note that when CET is enabled,
+ the GNU C Library requires CPUs capable of multi-byte NOPs, like
+ x86-64 processors as well as Intel Pentium Pro or newer.
+
+ NOTE: '--enable-cet' has been tested for i686, x86_64 and x32 on
+ non-CET processors. '--enable-cet' has been tested for x86_64 and
+ x32 on CET SDVs, but Intel CET support hasn't been validated for
+ i686.
+
'--disable-profile'
Don't build libraries with profiling information. You may want to
use this option if you don't plan to do profiling.
protection.
'--enable-bind-now'
- Disable lazy binding for installed shared objects. This provides
- additional security hardening because it enables full RELRO and a
- read-only global offset table (GOT), at the cost of slightly
- increased program load times.
+ Disable lazy binding for installed shared objects and programs.
+ This provides additional security hardening because it enables full
+ RELRO and a read-only global offset table (GOT), at the cost of
+ slightly increased program load times.
'--enable-pt_chown'
The file 'pt_chown' is a helper binary for 'grantpt' (*note
By default, libnsl is only built as shared library for backward
compatibility and the NSS modules libnss_compat, libnss_nis and
libnss_nisplus are not built at all. Use this option to enable
- libnsl with all depending NSS modules and header files.
+ libnsl with all depending NSS modules and header files. For
+ architectures and ABIs that have been added after version 2.28 of
+ the GNU C Library this option is not available, and the libnsl
+ compatibility library is not built.
+
+'--disable-crypt'
+ Do not install the passphrase-hashing library 'libcrypt' or the
+ header file 'crypt.h'. 'unistd.h' will still declare the function
+ 'crypt'. Using this option does not change the set of programs
+ that may need to be linked with '-lcrypt'; it only means that the
+ GNU C Library will not provide that library.
+
+ This option is for hackers and distributions experimenting with
+ independently-maintained implementations of libcrypt. It may
+ become the default in a future release.
'--disable-experimental-malloc'
By default, a per-thread cache is enabled in 'malloc'. While this
but you want to compile a library for 586es, give
'--host=i586-pc-linux-gnu' or just '--host=i586-linux' and add the
appropriate compiler flags ('-mcpu=i586' will do the trick) to
- CFLAGS.
+ 'CC'.
If you specify just '--build', 'configure' will get confused.
make the test run stop and exit with an error status immediately when a
failure occurs.
- The GNU C Library pretty printers come with their own set of scripts
-for testing, which run together with the rest of the testsuite through
-'make check'. These scripts require the following tools to run
-successfully:
-
- * Python 2.7.6/3.4.3 or later
-
- Python is required for running the printers' test scripts.
-
- * PExpect 4.0
-
- The printer tests drive GDB through test programs and compare its
- output to the printers'. PExpect is used to capture the output of
- GDB, and should be compatible with the Python version in your
- system.
-
- * GDB 7.8 or later with support for Python 2.7.6/3.4.3 or later
-
- GDB itself needs to be configured with Python support in order to
- use the pretty printers. Notice that your system having Python
- available doesn't imply that GDB supports it, nor that your
- system's Python and GDB's have the same version.
-
-If these tools are absent, the printer tests will report themselves as
-'UNSUPPORTED'. Notice that some of the printer tests require the GNU C
-Library to be compiled with debugging symbols.
-
To format the 'GNU C Library Reference Manual' for printing, type
'make dvi'. You need a working TeX installation to do this. The
distribution builds the on-line formatted version of the manual, as Info
setting a few variables in 'configparms'. Set 'CC' to the
cross-compiler for the target you configured the library for; it is
important to use this same 'CC' value when running 'configure', like
-this: 'CC=TARGET-gcc configure TARGET'. Set 'BUILD_CC' to the compiler
+this: 'configure TARGET CC=TARGET-gcc'. Set 'BUILD_CC' to the compiler
to use for programs run on the build system as part of compiling the
library. You may need to set 'AR' to cross-compiling versions of 'ar'
if the native tools are not configured to work with object files for the
using a Linux kernel with the 'devpts' filesystem enabled and mounted at
'/dev/pts', you don't need this program.
- After installation you might want to configure the timezone and
-locale installation of your system. The GNU C Library comes with a
-locale database which gets configured with 'localedef'. For example, to
-set up a German locale with name 'de_DE', simply issue the command
-'localedef -i de_DE -f ISO-8859-1 de_DE'. To configure all locales that
+ After installation you should configure the timezone and install
+locales for your system. The time zone configuration ensures that your
+system time matches the time for your current timezone. The locales
+ensure that the display of information on your system matches the
+expectations of your language and geographic region.
+
+ The GNU C Library is able to use two kinds of localization
+information sources, the first is a locale database named
+'locale-archive' which is generally installed as
+'/usr/lib/locale/locale-archive'. The locale archive has the benefit of
+taking up less space and being very fast to load, but only if you plan
+to install sixty or more locales. If you plan to install one or two
+locales you can instead install individual locales into their self-named
+directories e.g. '/usr/lib/locale/en_US.utf8'. For example to install
+the German locale using the character set for UTF-8 with name 'de_DE'
+into the locale archive issue the command 'localedef -i de_DE -f UTF-8
+de_DE', and to install just the one locale issue the command 'localedef
+--no-archive -i de_DE -f UTF-8 de_DE'. To configure all locales that
are supported by the GNU C Library, you can issue from your build
-directory the command 'make localedata/install-locales'.
+directory the command 'make localedata/install-locales' to install all
+locales into the locale archive or 'make
+localedata/install-locale-files' to install all locales as files in the
+default configured locale installation directory (derived from
+'--prefix' or '--localedir'). To install into an alternative system
+root use 'DESTDIR' e.g. 'make localedata/install-locale-files
+DESTDIR=/opt/glibc', but note that this does not change the configured
+prefix.
To configure the locally used timezone, set the 'TZ' environment
variable. The script 'tzselect' helps you to select the right value.
We recommend installing the following GNU tools before attempting to
build the GNU C Library:
- * GNU 'make' 3.79 or newer
+ * GNU 'make' 4.0 or newer
- You need the latest version of GNU 'make'. Modifying the GNU C
- Library to work with other 'make' programs would be so difficult
- that we recommend you port GNU 'make' instead. *Really.* We
- recommend GNU 'make' version 3.79. All earlier versions have
- severe bugs or lack features.
+ As of relase time, GNU 'make' 4.2.1 is the newest verified to work
+ to build the GNU C Library.
- * GCC 4.9 or newer
+ * GCC 6.2 or newer
- GCC 4.9 or higher is required. In general it is recommended to use
+ GCC 6.2 or higher is required. In general it is recommended to use
the newest version of the compiler that is known to work for
building the GNU C Library, as newer compilers usually produce
- better code. As of release time, GCC 7.1 is the newest compiler
+ better code. As of release time, GCC 9.1.1 is the newest compiler
verified to work to build the GNU C Library.
- For PowerPC 64-bits little-endian (powerpc64le), GCC 6.2 or higher
- is required. This compiler version is the first to provide the
- features required for building the GNU C Library with support for
- '_Float128'.
-
For multi-arch support it is recommended to use a GCC which has
been built with support for GNU indirect functions. This ensures
that correct debugging information is generated for functions
You must use GNU 'binutils' (as and ld) to build the GNU C Library.
No other assembler or linker has the necessary functionality at the
- moment. As of release time, GNU 'binutils' 2.27 is the newest
+ moment. As of release time, GNU 'binutils' 2.31.1 is the newest
verified to work to build the GNU C Library.
* GNU 'texinfo' 4.7 or later
need this version of the 'texinfo' package. Earlier versions do
not understand all the tags used in the document, and the
installation mechanism for the info files is not present or works
- differently. As of release time, 'texinfo' 6.0 is the newest
+ differently. As of release time, 'texinfo' 6.6 is the newest
verified to work to build the GNU C Library.
* GNU 'awk' 3.1.2, or higher
'awk' is used in several places to generate files. Some 'gawk'
extensions are used, including the 'asorti' function, which was
introduced in version 3.1.2 of 'gawk'. As of release time, 'gawk'
- version 4.1.3 is the newest verified to work to build the GNU C
+ version 4.2.1 is the newest verified to work to build the GNU C
Library.
* GNU 'bison' 2.7 or later
'bison' is used to generate the 'yacc' parser code in the 'intl'
- subdirectory.
+ subdirectory. As of release time, 'bison' version 3.0.5 is the
+ newest verified to work to build the GNU C Library.
* Perl 5
- Perl is not required, but it is used if present to test the
- installation. We may decide to use it elsewhere in the future.
+ Perl is not required, but if present it is used in some tests and
+ the 'mtrace' program, to build the GNU C Library manual. As of
+ release time 'perl' version 5.28.2 is the newest verified to work
+ to build the GNU C Library.
* GNU 'sed' 3.02 or newer
'Sed' is used in several places to generate files. Most scripts
work with any version of 'sed'. As of release time, 'sed' version
- 4.2.2 is the newest verified to work to build the GNU C Library.
+ 4.5 is the newest verified to work to build the GNU C Library.
+
+ * Python 3.4 or later
+
+ Python is required to build the GNU C Library. As of release time,
+ Python 3.7.4 is the newest verified to work for building and
+ testing the GNU C Library.
+
+ * PExpect 4.0
+
+ The pretty printer tests drive GDB through test programs and
+ compare its output to the printers'. PExpect is used to capture
+ the output of GDB, and should be compatible with the Python version
+ in your system. As of release time PExpect 4.3 is the newest
+ verified to work to test the pretty printers.
+
+ * GDB 7.8 or later with support for Python 2.7/3.4 or later
+
+ GDB itself needs to be configured with Python support in order to
+ use the pretty printers. Notice that your system having Python
+ available doesn't imply that GDB supports it, nor that your
+ system's Python and GDB's have the same version. As of release
+ time GNU 'debugger' 8.3 is the newest verified to work to test the
+ pretty printers.
+
+ Unless Python, PExpect and GDB with Python support are present, the
+ printer tests will report themselves as 'UNSUPPORTED'. Notice that
+ some of the printer tests require the GNU C Library to be compiled
+ with debugging symbols.
If you change any of the 'configure.ac' files you will also need
* GNU 'gettext' 0.10.36 or later
+ As of release time, GNU 'gettext' version 0.19.8.1 is the newest
+ version verified to work to build the GNU C Library.
+
You may also need these packages if you upgrade your source tree using
patches, although we try to avoid this.
call, if possible. This should not be too difficult.
The final step when you have a simple test case is to report the bug.
-Do this at <http://www.gnu.org/software/libc/bugs.html>.
+Do this at <https://www.gnu.org/software/libc/bugs.html>.
If you are not sure how a function should behave, and this manual
doesn't tell you, that's a bug in the manual. Report that too! If the
projects / thirdparty / glibc.git / blobdiff