library will still be usable, but functionality may be lost--for
example, you can't build a shared libc with old binutils.
+'--with-default-link'
+ With '--with-default-link', the build system does not use a custom
+ linker script for linking shared objects. The default is
+ '--without-default-link', because the custom linker script is
+ needed for full RELRO protection.
+
'--with-nonshared-cflags=CFLAGS'
Use additional compiler flags CFLAGS to build the parts of the
library which are always statically linked into applications and
particular case and potentially change debugging information and
metadata only).
+'--with-rtld-early-cflags=CFLAGS'
+ Use additional compiler flags CFLAGS to build the early startup
+ code of the dynamic linker. These flags can be used to enable
+ early dynamic linker diagnostics to run on CPUs which are not
+ compatible with the rest of the GNU C Library, for example, due to
+ compiler flags which target a later instruction set architecture
+ (ISA).
+
+'--with-timeoutfactor=NUM'
+ Specify an integer NUM to scale the timeout of test programs. This
+ factor can be changed at run time using 'TIMEOUTFACTOR' environment
+ variable.
+
'--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.
+'--disable-default-pie'
+ Don't build glibc programs and the testsuite as position
+ independent executables (PIE). By default, glibc programs and tests
+ are created as position independent executables on targets that
+ support it. If the toolchain and architecture support it, static
+ executables are built as static PIE and the resulting glibc can be
+ used with the GCC option, -static-pie, which is available with GCC
+ 8 or above, to create static PIE.
'--enable-cet'
'--enable-cet=permissive'
non-CET processors. '--enable-cet' has been tested for i686,
x86_64 and x32 on CET processors.
+'--enable-memory-tagging'
+ Enable memory tagging support if the architecture supports it.
+ When the GNU C Library is built with this option then the resulting
+ library will be able to control the use of tagged memory when
+ hardware support is present by use of the tunable
+ 'glibc.mem.tagging'. This includes the generation of tagged memory
+ when using the 'malloc' APIs.
+
+ At present only AArch64 platforms with MTE provide this
+ functionality, although the library will still operate (without
+ memory tagging) on older versions of the architecture.
+
+ The default is to disable support for memory tagging.
+
'--disable-profile'
Don't build libraries with profiling information. You may want to
use this option if you don't plan to do profiling.
(set glibc.malloc.tcache_count to zero), this option can be used to
remove it from the build completely.
+'--disable-scv'
+ Disable using 'scv' instruction for syscalls. All syscalls will
+ use 'sc' instead, even if the kernel supports 'scv'. PowerPC only.
+
'--build=BUILD-SYSTEM'
'--host=HOST-SYSTEM'
These options are for cross-compiling. If you specify both options
HOSTNAME is the host name of a system that can run the newly built
binaries of the GNU C Library. The source and build directories must be
visible at the same locations on both the build system and HOSTNAME.
+The 'cross-test-ssh.sh' script requires 'flock' from 'util-linux' to
+work when GLIBC_TEST_ALLOW_TIME_SETTING environment variable is set.
+
+ It is also possible to execute tests, which require setting the date
+on the target machine. Following use cases are supported:
+ * 'GLIBC_TEST_ALLOW_TIME_SETTING' is set in the environment in which
+ eligible tests are executed and have the privilege to run
+ 'clock_settime'. In this case, nothing prevents those tests from
+ running in parallel, so the caller shall assure that those tests
+ are serialized or provide a proper wrapper script for them.
+
+ * The 'cross-test-ssh.sh' script is used and one passes the
+ '--allow-time-setting' flag. In this case, both sets
+ 'GLIBC_TEST_ALLOW_TIME_SETTING' and serialization of test execution
+ are assured automatically.
In general, when testing the GNU C Library, 'test-wrapper' may be set
to the name and arguments of any program to run newly built binaries.
semantics being starting with an empty set of environment variables
rather than the ambient set.
+ For AArch64 with SVE, when testing the GNU C Library, 'test-wrapper'
+may be set to "SRCDIR/sysdeps/unix/sysv/linux/aarch64/vltest.py
+VECTOR-LENGTH" to change Vector Length.
+
Installing the C Library
========================
* GNU 'make' 4.0 or newer
- As of relase time, GNU 'make' 4.2.1 is the newest verified to work
- to build the GNU C Library.
+ As of relase time, GNU 'make' 4.4 is the newest verified to work to
+ build the GNU C Library.
* GCC 6.2 or newer
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 9.2.1 is the newest compiler
+ better code. As of release time, GCC 13.0 is the newest compiler
verified to work to build the GNU C Library.
For PowerPC 64-bits little-endian (powerpc64le), a GCC version with
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' 2.32 is the newest
+ moment. As of release time, GNU 'binutils' 2.39 is the newest
verified to work to build the GNU C Library.
For PowerPC 64-bits little-endian (powerpc64le), 'objcopy' is
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' 6.6 is the newest
+ differently. As of release time, 'texinfo' 7.0.2 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 5.0.1 is the newest verified to work to build the GNU C
+ version 5.1.1 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. As of release time, 'bison' version 3.4.1 is the
+ subdirectory. As of release time, 'bison' version 3.8.2 is the
newest verified to work to build the GNU C Library.
* Perl 5
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 5.30.1 is the newest verified to work
+ release time 'perl' version 5.36.0 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
- 4.5 is the newest verified to work to build the GNU C Library.
+ 4.8 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.
+ Python 3.11 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
+ in your system. As of release time PExpect 4.8.0 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
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
+ time GNU 'debugger' 12.1 is the newest verified to work to test the
pretty printers.
Unless Python, PExpect and GDB with Python support are present, the
* GNU 'gettext' 0.10.36 or later
- As of release time, GNU 'gettext' version 0.19.8.1 is the newest
+ As of release time, GNU 'gettext' version 0.21.1 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
Library with '--prefix=/usr'. If you set some other prefix or allow it
to default to '/usr/local', then all the components are installed there.
+ As of release time, Linux version 6.1.5 is the newest stable version
+verified to work to build the GNU C Library.
+
Reporting Bugs
==============