| @include macros.texi |
| @include pkgvers.texi |
| |
| @ifclear plain |
| @node Installation, Maintenance, Library Summary, Top |
| @end ifclear |
| |
| @c %MENU% How to install the GNU C Library |
| @appendix Installing @theglibc{} |
| |
| Before you do anything else, you should read the FAQ at |
| @url{https://sourceware.org/glibc/wiki/FAQ}. It answers common |
| questions and describes problems you may experience with compilation |
| and installation. |
| |
| You will need recent versions of several GNU tools: definitely GCC and |
| GNU Make, and possibly others. @xref{Tools for Compilation}, below. |
| |
| @ifclear plain |
| @menu |
| * Configuring and compiling:: How to compile and test GNU libc. |
| * Running make install:: How to install it once you've got it |
| compiled. |
| * Tools for Compilation:: You'll need these first. |
| * Linux:: Specific advice for GNU/Linux systems. |
| * Reporting Bugs:: So they'll get fixed. |
| @end menu |
| @end ifclear |
| |
| @node Configuring and compiling |
| @appendixsec Configuring and compiling @theglibc{} |
| @cindex configuring |
| @cindex compiling |
| |
| @Theglibc{} cannot be compiled in the source directory. You must build |
| it in a separate build directory. For example, if you have unpacked |
| the @glibcadj{} sources in @file{/src/gnu/glibc-@var{version}}, |
| 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. |
| |
| 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-@var{version}/configure @var{args@dots{}} |
| @end smallexample |
| |
| Please note that even though you're building in a separate build |
| directory, the compilation may need to create or modify files and |
| directories in the source directory. |
| |
| @noindent |
| @code{configure} takes many options, but the only one that is usually |
| mandatory is @samp{--prefix}. This option tells @code{configure} |
| where you want @theglibc{} installed. This defaults to @file{/usr/local}, |
| but the normal setting to install as the standard system library is |
| @samp{--prefix=/usr} for @gnulinuxsystems{} and @samp{--prefix=} (an |
| empty prefix) for @gnuhurdsystems{}. |
| |
| 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 |
| compiler that will be used, and @var{CFLAGS} sets optimization options |
| for the compiler. |
| |
| The following list describes all of the available options for |
| @code{configure}: |
| |
| @table @samp |
| @item --prefix=@var{directory} |
| Install machine-independent data files in subdirectories of |
| @file{@var{directory}}. The default is to install in @file{/usr/local}. |
| |
| @item --exec-prefix=@var{directory} |
| Install the library and other machine-dependent files in subdirectories |
| of @file{@var{directory}}. The default is to the @samp{--prefix} |
| directory if that option is specified, or @file{/usr/local} otherwise. |
| |
| @item --with-headers=@var{directory} |
| Look for kernel header files in @var{directory}, not |
| @file{/usr/include}. @Theglibc{} needs information from the kernel's header |
| files describing the interface to the kernel. @Theglibc{} will normally |
| look in @file{/usr/include} for them, |
| but if you specify this option, it will look in @var{DIRECTORY} instead. |
| |
| This option is primarily of use on a system where the headers in |
| @file{/usr/include} come from an older version of @theglibc{}. Conflicts can |
| occasionally happen in this case. You can also use this option if you want to |
| compile @theglibc{} with a newer set of kernel headers than the ones found in |
| @file{/usr/include}. |
| |
| @item --enable-kernel=@var{version} |
| This option is currently only useful on @gnulinuxsystems{}. The |
| @var{version} parameter should have the form X.Y.Z and describes the |
| smallest version of the Linux kernel the generated library is expected |
| to support. The higher the @var{version} number is, the less |
| compatibility code is added, and the faster the code gets. |
| |
| @item --with-binutils=@var{directory} |
| Use the binutils (assembler and linker) in @file{@var{directory}}, not |
| the ones the C compiler would default to. You can use this option if |
| the default binutils on your system cannot deal with all the constructs |
| in @theglibc{}. In that case, @code{configure} will detect the |
| problem and suppress these constructs, so that the library will still be |
| usable, but functionality may be lost---for example, you can't build a |
| shared libc with old binutils. |
| |
| @c disable static doesn't work currently |
| @c @item --disable-static |
| @c Don't build static libraries. Static libraries aren't that useful these |
| @c days, but we recommend you build them in case you need them. |
| |
| @item --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. |
| |
| @item --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. |
| |
| @item --disable-profile |
| Don't build libraries with profiling information. You may want to use |
| this option if you don't plan to do profiling. |
| |
| @item --enable-static-nss |
| Compile static versions of the NSS (Name Service Switch) libraries. |
| This is not recommended because it defeats the purpose of NSS; a program |
| linked statically with the NSS libraries cannot be dynamically |
| reconfigured to use a different name database. |
| |
| @item --enable-hardcoded-path-in-tests |
| By default, dynamic tests are linked to run with the installed C library. |
| This option hardcodes the newly built C library path in dynamic tests |
| so that they can be invoked directly. |
| |
| @item --disable-timezone-tools |
| By default, timezone related utilities (@command{zic}, @command{zdump}, |
| and @command{tzselect}) are installed with @theglibc{}. If you are building |
| these independently (e.g. by using the @samp{tzcode} package), then this |
| option will allow disabling the install of these. |
| |
| Note that you need to make sure the external tools are kept in sync with |
| the versions that @theglibc{} expects as the data formats may change over |
| time. Consult the @file{timezone} subdirectory for more details. |
| |
| @item --enable-stack-protector |
| @itemx --enable-stack-protector=strong |
| @itemx --enable-stack-protector=all |
| Compile the C library and all other parts of the glibc package |
| (including the threading and math libraries, NSS modules, and |
| transliteration modules) using the GCC @option{-fstack-protector}, |
| @option{-fstack-protector-strong} or @option{-fstack-protector-all} |
| options to detect stack overruns. Only the dynamic linker and a small |
| number of routines called directly from assembler are excluded from this |
| protection. |
| |
| @item --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. |
| |
| @pindex pt_chown |
| @findex grantpt |
| @item --enable-pt_chown |
| The file @file{pt_chown} is a helper binary for @code{grantpt} |
| (@pxref{Allocation, Pseudo-Terminals}) that is installed setuid root to |
| fix up pseudo-terminal ownership. It is not built by default because |
| systems using the Linux kernel are commonly built with the @code{devpts} |
| filesystem enabled and mounted at @file{/dev/pts}, which manages |
| pseudo-terminal ownership automatically. By using |
| @samp{--enable-pt_chown}, you may build @file{pt_chown} and install it |
| setuid and owned by @code{root}. The use of @file{pt_chown} introduces |
| additional security risks to the system and you should enable it only if |
| you understand and accept those risks. |
| |
| @item --disable-werror |
| By default, @theglibc{} is built with @option{-Werror}. If you wish |
| to build without this option (for example, if building with a newer |
| version of GCC than this version of @theglibc{} was tested with, so |
| new warnings cause the build with @option{-Werror} to fail), you can |
| configure with @option{--disable-werror}. |
| |
| @item --disable-mathvec |
| By default for x86_64, @theglibc{} is built with the vector math library. |
| Use this option to disable the vector math library. |
| |
| @item --enable-tunables |
| Tunables support allows additional library parameters to be customized at |
| runtime. This feature is enabled by default. This option can take the |
| following values: |
| |
| @table @code |
| @item yes |
| This is the default if no option is passed to configure. This enables tunables |
| and selects the default frontend (currently @samp{valstring}). |
| |
| @item no |
| This option disables tunables. |
| |
| @item valstring |
| This enables tunables and selects the @samp{valstring} frontend for tunables. |
| This frontend allows users to specify tunables as a colon-separated list in a |
| single environment variable @env{GLIBC_TUNABLES}. |
| @end table |
| |
| @item --enable-obsolete-nsl |
| 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. |
| |
| @item --disable-experimental-malloc |
| By default, a per-thread cache is enabled in @code{malloc}. While |
| this cache can be disabled on a per-application basis using tunables |
| (set glibc.malloc.tcache_count to zero), this option can be used to |
| remove it from the build completely. |
| |
| @item --build=@var{build-system} |
| @itemx --host=@var{host-system} |
| These options are for cross-compiling. If you specify both options and |
| @var{build-system} is different from @var{host-system}, @code{configure} |
| will prepare to cross-compile @theglibc{} from @var{build-system} to be used |
| on @var{host-system}. You'll probably need the @samp{--with-headers} |
| option too, and you may have to override @var{configure}'s selection of |
| the compiler and/or binutils. |
| |
| If you only specify @samp{--host}, @code{configure} will prepare for a |
| native compile but use what you specify instead of guessing what your |
| system is. This is most useful to change the CPU submodel. For example, |
| if @code{configure} guesses your machine as @code{i686-pc-linux-gnu} but |
| you want to compile a library for 586es, give |
| @samp{--host=i586-pc-linux-gnu} or just @samp{--host=i586-linux} and add |
| the appropriate compiler flags (@samp{-mcpu=i586} will do the trick) to |
| @var{CFLAGS}. |
| |
| If you specify just @samp{--build}, @code{configure} will get confused. |
| |
| @item --with-pkgversion=@var{version} |
| Specify a description, possibly including a build number or build |
| date, of the binaries being built, to be included in |
| @option{--version} output from programs installed with @theglibc{}. |
| For example, @option{--with-pkgversion='FooBar GNU/Linux glibc build |
| 123'}. The default value is @samp{GNU libc}. |
| |
| @item --with-bugurl=@var{url} |
| Specify the URL that users should visit if they wish to report a bug, |
| to be included in @option{--help} output from programs installed with |
| @theglibc{}. The default value refers to the main bug-reporting |
| information for @theglibc{}. |
| @end table |
| |
| To build the library and related programs, type @code{make}. This will |
| produce a lot of output, some of which may look like errors from |
| @code{make} but aren't. Look for error messages from @code{make} |
| containing @samp{***}. Those indicate that something is seriously wrong. |
| |
| 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 |
| GNU @code{make} version, though. |
| |
| To build and run test programs which exercise some of the library |
| facilities, type @code{make check}. If it does not complete |
| successfully, do not use the built library, and report a bug after |
| verifying that the problem is not already known. @xref{Reporting Bugs}, |
| for instructions on reporting bugs. Note that some of the tests assume |
| they are not being run by @code{root}. We recommend you compile and |
| test @theglibc{} as an unprivileged user. |
| |
| Before reporting bugs make sure there is no problem with your system. |
| The tests (and later installation) use some pre-existing files of the |
| system such as @file{/etc/passwd}, @file{/etc/nsswitch.conf} and others. |
| These files must all contain correct and sensible content. |
| |
| Normally, @code{make check} will run all the tests before reporting |
| all problems found and exiting with error status if any problems |
| occurred. You can specify @samp{stop-on-test-failure=y} when running |
| @code{make check} to make the test run stop and exit with an error |
| status immediately when a failure occurs. |
| |
| The @glibcadj{} pretty printers come with their own set of scripts for testing, |
| which run together with the rest of the testsuite through @code{make check}. |
| These scripts require the following tools to run successfully: |
| |
| @itemize @bullet |
| @item |
| Python 2.7.6/3.4.3 or later |
| |
| Python is required for running the printers' test scripts. |
| |
| @item 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. |
| |
| @item |
| 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. |
| @end itemize |
| |
| @noindent |
| If these tools are absent, the printer tests will report themselves as |
| @code{UNSUPPORTED}. Notice that some of the printer tests require @theglibc{} |
| to be compiled with debugging symbols. |
| |
| To format the @cite{GNU C Library Reference Manual} for printing, type |
| @w{@code{make dvi}}. You need a working @TeX{} installation to do |
| this. The distribution builds the on-line formatted version of the |
| manual, as Info files, as part of the build process. You can build |
| them manually with @w{@code{make info}}. |
| |
| The library has a number of special-purpose configuration parameters |
| which you can find in @file{Makeconfig}. These can be overwritten with |
| the file @file{configparms}. To change them, create a |
| @file{configparms} in your build directory and add values as appropriate |
| for your system. The file is included and parsed by @code{make} and has |
| to follow the conventions for makefiles. |
| |
| It is easy to configure @theglibc{} for cross-compilation by |
| setting a few variables in @file{configparms}. Set @code{CC} to the |
| cross-compiler for the target you configured the library for; it is |
| important to use this same @code{CC} value when running |
| @code{configure}, like this: @samp{CC=@var{target}-gcc configure |
| @var{target}}. Set @code{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 @code{AR} to cross-compiling versions of @code{ar} |
| if the native tools are not configured to work with |
| object files for the target you configured for. When cross-compiling |
| @theglibc{}, it may be tested using @samp{make check |
| test-wrapper="@var{srcdir}/scripts/cross-test-ssh.sh @var{hostname}"}, |
| where @var{srcdir} is the absolute directory name for the main source |
| directory and @var{hostname} is the host name of a system that can run |
| the newly built binaries of @theglibc{}. The source and build |
| directories must be visible at the same locations on both the build |
| system and @var{hostname}. |
| |
| In general, when testing @theglibc{}, @samp{test-wrapper} may be set |
| to the name and arguments of any program to run newly built binaries. |
| This program must preserve the arguments to the binary being run, its |
| working directory and the standard input, output and error file |
| descriptors. If @samp{@var{test-wrapper} env} will not work to run a |
| program with environment variables set, then @samp{test-wrapper-env} |
| must be set to a program that runs a newly built program with |
| environment variable assignments in effect, those assignments being |
| specified as @samp{@var{var}=@var{value}} before the name of the |
| program to be run. If multiple assignments to the same variable are |
| specified, the last assignment specified must take precedence. |
| Similarly, if @samp{@var{test-wrapper} env -i} will not work to run a |
| program with an environment completely empty of variables except those |
| directly assigned, then @samp{test-wrapper-env-only} must be set; its |
| use has the same syntax as @samp{test-wrapper-env}, the only |
| difference in its semantics being starting with an empty set of |
| environment variables rather than the ambient set. |
| |
| |
| @node Running make install |
| @appendixsec Installing the C Library |
| @cindex installing |
| |
| To install the library and its header files, and the Info files of the |
| manual, type @code{make install}. This will |
| build things, if necessary, before installing them; however, you should |
| still compile everything first. If you are installing @theglibc{} as your |
| primary C library, we recommend that you shut the system down to |
| single-user mode first, and reboot afterward. This minimizes the risk |
| of breaking things when the library changes out from underneath. |
| |
| @samp{make install} will do the entire job of upgrading from a |
| previous installation of @theglibc{} version 2.x. There may sometimes |
| be headers |
| left behind from the previous installation, but those are generally |
| harmless. If you want to avoid leaving headers behind you can do |
| things in the following order. |
| |
| You must first build the library (@samp{make}), optionally check it |
| (@samp{make check}), switch the include directories and then install |
| (@samp{make install}). The steps must be done in this order. Not moving |
| the directory before install will result in an unusable mixture of header |
| files from both libraries, but configuring, building, and checking the |
| library requires the ability to compile and run programs against the old |
| library. The new @file{/usr/include}, after switching the include |
| directories and before installing the library should contain the Linux |
| headers, but nothing else. If you do this, you will need to restore |
| any headers from libraries other than @theglibc{} yourself after installing the |
| library. |
| |
| You can install @theglibc{} somewhere other than where you configured |
| it to go by setting the @code{DESTDIR} GNU standard make variable on |
| the command line for @samp{make install}. The value of this variable |
| is prepended to all the paths for installation. This is useful when |
| setting up a chroot environment or preparing a binary distribution. |
| The directory should be specified with an absolute file name. Installing |
| with the @code{prefix} and @code{exec_prefix} GNU standard make variables |
| set is not supported. |
| |
| @Theglibc{} includes a daemon called @code{nscd}, which you |
| may or may not want to run. @code{nscd} caches name service lookups; it |
| can dramatically improve performance with NIS+, and may help with DNS as |
| well. |
| |
| One auxiliary program, @file{/usr/libexec/pt_chown}, is installed setuid |
| @code{root} if the @samp{--enable-pt_chown} configuration option is used. |
| This program is invoked by the @code{grantpt} function; it sets the |
| permissions on a pseudoterminal so it can be used by the calling process. |
| If you are using a Linux kernel with the @code{devpts} filesystem enabled |
| and mounted at @file{/dev/pts}, you don't need this program. |
| |
| After installation you might want to configure the timezone and locale |
| installation of your system. @Theglibc{} comes with a locale |
| database which gets configured with @code{localedef}. For example, to |
| set up a German locale with name @code{de_DE}, simply issue the command |
| @samp{localedef -i de_DE -f ISO-8859-1 de_DE}. To configure all locales |
| that are supported by @theglibc{}, you can issue from your build directory the |
| command @samp{make localedata/install-locales}. |
| |
| To configure the locally used timezone, set the @code{TZ} environment |
| variable. The script @code{tzselect} helps you to select the right value. |
| As an example, for Germany, @code{tzselect} would tell you to use |
| @samp{TZ='Europe/Berlin'}. For a system wide installation (the given |
| paths are for an installation with @samp{--prefix=/usr}), link the |
| timezone file which is in @file{/usr/share/zoneinfo} to the file |
| @file{/etc/localtime}. For Germany, you might execute @samp{ln -s |
| /usr/share/zoneinfo/Europe/Berlin /etc/localtime}. |
| |
| @node Tools for Compilation |
| @appendixsec Recommended Tools for Compilation |
| @cindex installation tools |
| @cindex tools, for installing library |
| |
| We recommend installing the following GNU tools before attempting to |
| build @theglibc{}: |
| |
| @itemize @bullet |
| @item |
| GNU @code{make} 3.79 or newer |
| |
| You need the latest version of GNU @code{make}. Modifying @theglibc{} |
| to work with other @code{make} programs would be so difficult that |
| we recommend you port GNU @code{make} instead. @strong{Really.} We |
| recommend GNU @code{make} version 3.79. All earlier versions have severe |
| bugs or lack features. |
| |
| @item |
| GCC 4.9 or newer |
| |
| GCC 4.9 or higher is required. In general it is recommended to use |
| the newest version of the compiler that is known to work for building |
| @theglibc{}, as newer compilers usually produce better code. As of |
| release time, GCC 7.3 is the newest compiler verified to work to build |
| @theglibc{}. |
| |
| 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 @theglibc{} with support for @code{_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 selected by IFUNC resolvers. This |
| support can either be enabled by configuring GCC with |
| @samp{--enable-gnu-indirect-function}, or by enabling it by default by setting |
| @samp{default_gnu_indirect_function} variable for a particular architecture in |
| the GCC source file @file{gcc/config.gcc}. |
| |
| You can use whatever compiler you like to compile programs that use |
| @theglibc{}. |
| |
| Check the FAQ for any special compiler issues on particular platforms. |
| |
| @item |
| GNU @code{binutils} 2.25 or later |
| |
| You must use GNU @code{binutils} (as and ld) to build @theglibc{}. |
| No other assembler or linker has the necessary functionality at the |
| moment. As of release time, GNU @code{binutils} 2.29.1 is the newest |
| verified to work to build @theglibc{}. |
| |
| @item |
| GNU @code{texinfo} 4.7 or later |
| |
| To correctly translate and install the Texinfo documentation you need |
| this version of the @code{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, @code{texinfo} 6.5 is the newest verified to work |
| to build @theglibc{}. |
| |
| @item |
| GNU @code{awk} 3.1.2, or higher |
| |
| @code{awk} is used in several places to generate files. |
| Some @code{gawk} extensions are used, including the @code{asorti} |
| function, which was introduced in version 3.1.2 of @code{gawk}. |
| As of release time, @code{gawk} version 4.2.0 is the newest verified |
| to work to build @theglibc{}. |
| |
| @item |
| GNU @code{bison} 2.7 or later |
| |
| @code{bison} is used to generate the @code{yacc} parser code in the @file{intl} |
| subdirectory. As of release time, @code{bison} version 3.0.4 is the newest |
| verified to work to build @theglibc{}. |
| |
| @item |
| 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. |
| |
| @item |
| GNU @code{sed} 3.02 or newer |
| |
| @code{Sed} is used in several places to generate files. Most scripts work |
| with any version of @code{sed}. As of release time, @code{sed} version |
| 4.4 is the newest verified to work to build @theglibc{}. |
| |
| @end itemize |
| |
| @noindent |
| If you change any of the @file{configure.ac} files you will also need |
| |
| @itemize @bullet |
| @item |
| GNU @code{autoconf} 2.69 (exactly) |
| @end itemize |
| |
| @noindent |
| and if you change any of the message translation files you will need |
| |
| @itemize @bullet |
| @item |
| GNU @code{gettext} 0.10.36 or later |
| @end itemize |
| |
| |
| @noindent |
| You may also need these packages if you upgrade your source tree using |
| patches, although we try to avoid this. |
| |
| @node Linux |
| @appendixsec Specific advice for @gnulinuxsystems{} |
| @cindex kernel header files |
| |
| If you are installing @theglibc{} on @gnulinuxsystems{}, you need to have |
| the header files from a 3.2 or newer kernel around for reference. |
| (For the ia64 architecture, you need version 3.2.18 or newer because this |
| is the first version with support for the @code{accept4} system call.) |
| These headers must be installed using @samp{make headers_install}; the |
| headers present in the kernel source directory are not suitable for |
| direct use by @theglibc{}. You do not need to use that kernel, just have |
| its headers installed where @theglibc{} can access them, referred to here as |
| @var{install-directory}. The easiest way to do this is to unpack it |
| in a directory such as @file{/usr/src/linux-@var{version}}. In that |
| directory, run @samp{make headers_install |
| INSTALL_HDR_PATH=@var{install-directory}}. Finally, configure @theglibc{} |
| with the option @samp{--with-headers=@var{install-directory}/include}. |
| Use the most recent kernel you can get your hands on. (If you are |
| cross-compiling @theglibc{}, you need to specify |
| @samp{ARCH=@var{architecture}} in the @samp{make headers_install} |
| command, where @var{architecture} is the architecture name used by the |
| Linux kernel, such as @samp{x86} or @samp{powerpc}.) |
| |
| After installing @theglibc{}, you may need to remove or rename |
| directories such as @file{/usr/include/linux} and |
| @file{/usr/include/asm}, and replace them with copies of directories |
| such as @file{linux} and @file{asm} from |
| @file{@var{install-directory}/include}. All directories present in |
| @file{@var{install-directory}/include} should be copied, except that |
| @theglibc{} provides its own version of @file{/usr/include/scsi}; the |
| files provided by the kernel should be copied without replacing those |
| provided by @theglibc{}. The @file{linux}, @file{asm} and |
| @file{asm-generic} directories are required to compile programs using |
| @theglibc{}; the other directories describe interfaces to the kernel but |
| are not required if not compiling programs using those interfaces. |
| You do not need to copy kernel headers if you did not specify an |
| alternate kernel header source using @samp{--with-headers}. |
| |
| The Filesystem Hierarchy Standard for @gnulinuxsystems{} expects some |
| components of the @glibcadj{} installation to be in |
| @file{/lib} and some in @file{/usr/lib}. This is handled automatically |
| if you configure @theglibc{} with @samp{--prefix=/usr}. If you set some other |
| prefix or allow it to default to @file{/usr/local}, then all the |
| components are installed there. |
| |
| @node Reporting Bugs |
| @appendixsec Reporting Bugs |
| @cindex reporting bugs |
| @cindex bugs, reporting |
| |
| There are probably bugs in @theglibc{}. There are certainly |
| errors and omissions in this manual. If you report them, they will get |
| fixed. If you don't, no one will ever know about them and they will |
| remain unfixed for all eternity, if not longer. |
| |
| It is a good idea to verify that the problem has not already been |
| reported. Bugs are documented in two places: The file @file{BUGS} |
| describes a number of well known bugs and the central @glibcadj{} |
| bug tracking system has a |
| WWW interface at |
| @url{https://sourceware.org/bugzilla/}. The WWW |
| interface gives you access to open and closed reports. A closed report |
| normally includes a patch or a hint on solving the problem. |
| |
| To report a bug, first you must find it. With any luck, this will be the |
| hard part. Once you've found a bug, make sure it's really a bug. A |
| good way to do this is to see if @theglibc{} behaves the same way |
| some other C library does. If so, probably you are wrong and the |
| libraries are right (but not necessarily). If not, one of the libraries |
| is probably wrong. It might not be @theglibc{}. Many historical |
| Unix C libraries permit things that we don't, such as closing a file |
| twice. |
| |
| If you think you have found some way in which @theglibc{} does not |
| conform to the ISO and POSIX standards (@pxref{Standards and |
| Portability}), that is definitely a bug. Report it! |
| |
| Once you're sure you've found a bug, try to narrow it down to the |
| smallest test case that reproduces the problem. In the case of a C |
| library, you really only need to narrow it down to one library |
| function 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 @value{REPORT_BUGS_TO}. |
| |
| 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 |
| function's behavior disagrees with the manual, then either the library |
| or the manual has a bug, so report the disagreement. If you find any |
| errors or omissions in this manual, please report them to the |
| bug database. If you refer to specific |
| sections of the manual, please include the section names for easier |
| identification. |