Commit Graph

1519 Commits

Author SHA1 Message Date
Florian Weimer
477910b83e Linux: Move timer_settime, __timer_settime64 from librt to libc
The symbols were moved using scripts/move-symbol-to-libc.py.

The way the ABI intransition is implemented is changed with this
commit: the implementation is now consolidated in one file with a
TIMER_T_WAS_INT_COMPAT check.

The shared librt is now empty, so this commit adds a placeholder
symbol at the base version, GLIBC_2.2, and potentially at the
GLIBC_2.3.3 version as well (the leftover from the int/timer_t ABI
transition).

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-06-28 09:51:01 +02:00
Florian Weimer
a1d6ed027b Linux: Move timer_gettime, __timer_gettime64 from librt to libc
The symbols were moved using scripts/move-symbol-to-libc.py.

The way the ABI intransition is implemented is changed with this
commit: the implementation is now consolidated in one file with a
TIMER_T_WAS_INT_COMPAT check.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-06-28 09:51:01 +02:00
Shen-Ta Hsieh
447954a206 math: redirect roundeven function
This patch redirect roundeven function for futhermore changes.

Signed-off-by: Shen-Ta Hsieh <ibmibmibm.tw@gmail.com>
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
2021-06-27 07:56:57 -07:00
Florian Weimer
5b3a2abfb3 Linux: Move mq_send, mq_timedsend, __mq_timedsend_time64 to libc
The symbols were moved using scripts/move-symbol-to-libc.py.

Reviewed-by: Adhemerva Zanella  <adhemerval.zanella@linaro.org>
2021-06-25 12:21:12 +02:00
Florian Weimer
903e6f9960 Linux: Move mq_receive, mq_timedreceive, __mq_timedreceive_time64 to libc
The symbols were moved using scripts/move-symbol-to-libc.py.

Reviewed-by: Adhemerva Zanella  <adhemerval.zanella@linaro.org>
2021-06-25 12:21:12 +02:00
Florian Weimer
2da5f22fff Linux: Move mq_notify from librt to libc
The symbol was moved using scripts/move-symbol-to-libc.py.

An explicit call from fork into the mq_notify implementation replaces
the previous use of pthread_atfork.

Reviewed-by: Adhemerva Zanella  <adhemerval.zanella@linaro.org>
2021-06-25 12:20:47 +02:00
Florian Weimer
a752cb670a Linux: Move mq_setattr from librt to libc
The symbol was moved using scripts/move-symbol-to-libc.py.

To introduce the proper symbol versioning, the implementation of
the system call wrapper us moved to a C file.

Reviewed-by: Adhemerva Zanella  <adhemerval.zanella@linaro.org>
2021-06-25 12:19:58 +02:00
Florian Weimer
32e750516c Linux: Move aio_suspend, aio_suspend64, __aio_suspend_time64 to libc
The symbols were moved using scripts/move-symbol-to-libc.py.

There is a minor oddity here: This is generic code shared with Hurd,
and Hurd does not have time64 support.  This is why the
versioned_symbol export for __aio_suspend_time64 is restricted to
the PTHREAD_IN_LIBC code.

Reviewed-by: Adhemerva Zanella  <adhemerval.zanella@linaro.org>
2021-06-25 11:55:27 +02:00
Adhemerval Zanella
9a75654037 posix: Consolidate fork implementation
The Linux nptl implementation is used as base for generic fork
implementation to handle the internal locks and mutexes.  The
system specific bits are moved a new internal _Fork symbol.

(This new implementation will be used to provide a async-signal-safe
_Fork now that POSIX has clarified that fork might not be
async-signal-safe [1]).

For Hurd it means that the __nss_database_fork_prepare_parent and
__nss_database_fork_subprocess will be run in a slight different
order.

[1] https://austingroupbugs.net/view.php?id=62
2021-06-24 10:02:06 -03:00
Adhemerval Zanella
4c3df0eba5 linux: Only use 64-bit syscall if required for select
For !__ASSUME_TIME64_SYSCALLS there is no need to issue a 64-bit syscall
if the provided timeout fits in a 32-bit one.  The 64-bit usage should
be rare since the timeout is a relative one.  This also avoids the need
to use supports_time64() (which breaks the usage case of live migration
like CRIU or similar).

It also fixes an issue on 32-bit select call for !__ASSUME_PSELECT
(microblase with older kernels only) where the expected timeout
is a 'struct timeval' instead of 'struct timespec'.

Checked on i686-linux-gnu on a 4.15 kernel and on a 5.11 kernel
(with and without --enable-kernel=5.1) and on x86_64-linux-gnu.

Reviewed-by: Lukasz Majewski <lukma@denx.de>
2021-06-22 12:09:52 -03:00
Adhemerval Zanella
52a5fe70a2 Use 64 bit time_t stat internally
For the legacy ABI with supports 32-bit time_t it calls the 64-bit
time directly, since the LFS symbols calls the 64-bit time_t ones
internally.

Checked on i686-linux-gnu and x86_64-linux-gnu.

Reviewed-by: Lukasz Majewski <lukma@denx.de>
2021-06-22 12:09:52 -03:00
Florian Weimer
412b05fec9 Add hidden prototypes for fsync, fdatasync
Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-06-22 09:51:14 +02:00
Adhemerval Zanella
19873b18b0 io: Add ftw64 with 64-bit time_t support
Similar to fts, ftw routines passes a stat pointer that might
differ of size and layout when 64-bit time API is used.

Checked on i686-linux-gnu and x86_64-linux-gnu.

Reviewed-by: Lukasz Majewski <lukma@denx.de>
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-06-15 10:42:11 -03:00
Adhemerval Zanella
70961aee18 io: Add fts64 with 64-bit time_t support
Similar to glob, fts routines passes a stat pointer that might
differ of size and layout when 64-bit time API is used.

Checked on i686-linux-gnu and x86_64-linux-gnu.

Reviewed-by: Lukasz Majewski <lukma@denx.de>
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-06-15 10:42:11 -03:00
Adhemerval Zanella
84f7ce8447 posix: Add glob64 with 64-bit time_t support
The glob might pass a different stat struct for gl_stat and gl_lstat
when GLOB_ALTDIRFUNC is used.  This requires add a new 64-bit time
version that also uses 64-bit time stat functions.

Checked on i686-linux-gnu and x86_64-linux-gnu.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-06-15 10:42:11 -03:00
Adhemerval Zanella
47f24c21ee y2038: Add support for 64-bit time on legacy ABIs
A new build flag, _TIME_BITS, enables the usage of the newer 64-bit
time symbols for legacy ABI (where 32-bit time_t is default).  The 64
bit time support is only enabled if LFS (_FILE_OFFSET_BITS=64) is
also used.

Different than LFS support, the y2038 symbols are added only for the
required ABIs (armhf, csky, hppa, i386, m68k, microblaze, mips32,
mips64-n32, nios2, powerpc32, sparc32, s390-32, and sh).  The ABIs with
64-bit time support are unchanged, both for symbol and types
redirection.

On Linux the full 64-bit time support requires a minimum of kernel
version v5.1.  Otherwise, the 32-bit fallbacks are used and might
results in error with overflow return code (EOVERFLOW).

The i686-gnu does not yet support 64-bit time.

This patch exports following rediretions to support 64-bit time:

  * libc:
    adjtime
    adjtimex
    clock_adjtime
    clock_getres
    clock_gettime
    clock_nanosleep
    clock_settime
    cnd_timedwait
    ctime
    ctime_r
    difftime
    fstat
    fstatat
    futimens
    futimes
    futimesat
    getitimer
    getrusage
    gettimeofday
    gmtime
    gmtime_r
    localtime
    localtime_r
    lstat_time
    lutimes
    mktime
    msgctl
    mtx_timedlock
    nanosleep
    nanosleep
    ntp_gettime
    ntp_gettimex
    ppoll
    pselec
    pselect
    pthread_clockjoin_np
    pthread_cond_clockwait
    pthread_cond_timedwait
    pthread_mutex_clocklock
    pthread_mutex_timedlock
    pthread_rwlock_clockrdlock
    pthread_rwlock_clockwrlock
    pthread_rwlock_timedrdlock
    pthread_rwlock_timedwrlock
    pthread_timedjoin_np
    recvmmsg
    sched_rr_get_interval
    select
    sem_clockwait
    semctl
    semtimedop
    sem_timedwait
    setitimer
    settimeofday
    shmctl
    sigtimedwait
    stat
    thrd_sleep
    time
    timegm
    timerfd_gettime
    timerfd_settime
    timespec_get
    utime
    utimensat
    utimes
    utimes
    wait3
    wait4

  * librt:
    aio_suspend
    mq_timedreceive
    mq_timedsend
    timer_gettime
    timer_settime

  * libanl:
    gai_suspend

Reviewed-by: Lukasz Majewski <lukma@denx.de>
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-06-15 10:42:11 -03:00
Adhemerval Zanella
8af344feb5 time: Add 64-bit time support for getdate
The getdate is basically a wrapper localtime and mktime.  The 64-bit
time support is done calling the 64-bit internal functions, there is
no need to add a new symbol version.

Checked on x86_64-linux-gnu and i686-linux-gnu.

Reviewed-by: Lukasz Majewski <lukma@denx.de>
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-06-15 10:42:11 -03:00
Adhemerval Zanella
13c51549e2 linux: Add fallback for 64-bit time_t SO_TIMESTAMP{NS}
The recvmsg handling is more complicated because it requires check the
returned kernel control message and make some convertions.  For
!__ASSUME_TIME64_SYSCALLS it converts the first 32-bit time SO_TIMESTAMP
or SO_TIMESTAMPNS and appends it to the control buffer if has extra
space or returns MSG_CTRUNC otherwise.  The 32-bit time field is kept
as-is.

Calls with __TIMESIZE=32 will see the converted 64-bit time control
messages as spurious control message of unknown type.  Calls with
__TIMESIZE=64 running on pre-time64 kernels will see the original
message as a spurious control ones of unknown typ while running on
kernel with native 64-bit time support will only see the time64 version
of the control message.

Checked on x86_64-linux-gnu and i686-linux-gnu (on 5.4 and on 4.15
kernel).

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-06-15 10:42:06 -03:00
Adhemerval Zanella
f779b1efb3 nptl: Implement raise in terms of pthread_kill
Now that pthread_kill is provided by libc.so it is possible to
implement the generic POSIX implementation as
'pthread_kill(pthread_self(), sig)'.

For Linux implementation, pthread_kill read the targeting TID from
the TCB.  For raise, this it not possible because it would make raise
fail when issue after vfork (where creates the resulting process
has a different TID from the parent, but its TCB is not updated as
for pthread_create).  To make raise use pthread_kill, it is make
usable from vfork by getting the target thread id through gettid
syscall.

Checked on x86_64-linux-gnu and aarch64-linux-gnu.
2021-06-09 15:16:45 -03:00
Florian Weimer
466c1ea15f dlfcn: Rework static dlopen hooks
Consolidate all hooks structures into a single one.  There are
no static dlopen ABI concerns because glibc 2.34 already comes
with substantial ABI-incompatible changes in this area.  (Static
dlopen requires the exact same dynamic glibc version that was used
for static linking.)

The new approach uses a pointer to the hooks structure into
_rtld_global_ro and initalizes it in __rtld_static_init.  This avoids
a back-and-forth with various callback functions.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-06-03 09:12:05 +02:00
Florian Weimer
6f1c701026 dlfcn: Cleanups after -ldl is no longer required
This commit removes the ELF constructor and internal variables from
dlfcn/dlfcn.c.  The file now serves the same purpose as
nptl/libpthread-compat.c, so it is renamed to dlfcn/libdl-compat.c.
The use of libdl-shared-only-routines ensures that libdl.a is empty.

This commit adjusts the test suite not to use $(libdl).  The libdl.so
symbolic link is no longer installed.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-06-03 09:11:45 +02:00
Florian Weimer
0c1c3a771e dlfcn: Move dlopen into libc
The symbol was moved using scripts/move-symbol-to-libc.py.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-06-03 08:26:04 +02:00
Florian Weimer
add8d7ea01 dlfcn: Move dlvsym into libc
The symbol was moved using scripts/move-symbol-to-libc.py.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-06-03 08:26:04 +02:00
Florian Weimer
6dfc0207eb dlfcn: Move dlinfo into libc
The symbol was moved using scripts/move-symbol-to-libc.py.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-06-03 08:26:04 +02:00
Florian Weimer
492560a32e dlfcn: Move dladdr1 into libc
The symbol was moved using scripts/move-symbol-to-libc.py.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-06-03 08:26:04 +02:00
Florian Weimer
6a1ed32789 dlfcn: Move dlmopen into libc
The symbol was moved using scripts/move-symbol-to-libc.py.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-06-03 08:26:04 +02:00
Florian Weimer
77f876c0e3 dlfcn: Move dlsym into libc
The symbol was moved using scripts/move-symbol-to-libc.py.

In elf/Makefile, remove the $(libdl) dependency from testobj1.so
because it the unused libdl DSO now causes elf/tst-unused-deps to
fail.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-06-03 08:26:04 +02:00
Florian Weimer
602252b553 dlfcn: Move dladdr into libc
The symbol was moved using scripts/move-symbol-to-libc.py.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-06-03 08:26:04 +02:00
Florian Weimer
d8cce17d2a dlfcn: Move dlclose into libc
The symbol was moved using scripts/move-symbol-to-libc.py.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-06-03 08:26:04 +02:00
Florian Weimer
a23c28ec0d dlfcn: Move dlerror into libc
The symbol was moved using scripts/move-symbol-to-libc.py.

There is a minor functionality enhancement: dlerror now sets
errno if it was set as part of the exception.  (This is the result
of using %m in asprintf, to avoid the strerror PLT call.) The
previous errno value upon function return was unpredictable.
Documenting this as a feature is premature; we need to make sure
that the error codes are meaningful when they are set by the dynamic
loader.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-06-02 09:06:10 +02:00
Joseph Myers
858045ad1c Update floating-point feature test macro handling for C2X
ISO C2X has made some changes to the handling of feature test macros
related to features from the floating-point TSes, and to exactly what
such features are present in what headers, that require corresponding
changes in glibc.

* For the few features that were controlled by
  __STDC_WANT_IEC_60559_BFP_EXT__ (and the corresponding DFP macro) in
  C2X, there is now instead a new feature test macro
  __STDC_WANT_IEC_60559_EXT__ covering both binary and decimal FP.
  This controls CR_DECIMAL_DIG in <float.h> (provided by GCC; I
  implemented support for the new feature test macro for GCC 11) and
  the totalorder and payload functions in <math.h>.  C2X no longer
  says anything about __STDC_WANT_IEC_60559_BFP_EXT__ (so it's
  appropriate for that macro to continue to enable exactly the
  features from TS 18661-1).

* The SNAN macros for each floating-point type have moved to <float.h>
  (and been renamed in the process).  Thus, the copies in <math.h>
  should only be defined for __STDC_WANT_IEC_60559_BFP_EXT__, not for
  C2X.

* The fmaxmag and fminmag functions have been removed (replaced by new
  functions for the new min/max operations in IEEE 754-2019).  Thus
  those should also only be declared for
  __STDC_WANT_IEC_60559_BFP_EXT__.

* The _FloatN / _FloatNx handling for the last two points in glibc is
  trickier, since __STDC_WANT_IEC_60559_TYPES_EXT__ is still in C2X
  (the integration of TS 18661-3 as an Annex, that is, which hasn't
  yet been merged into the C standard git repository but has been
  accepted by WG14), so C2X with that macro should not declare some
  things that are declared for older standards with that macro.  The
  approach taken here is to provide the declarations (when
  __STDC_WANT_IEC_60559_TYPES_EXT__ is enabled) only when (defined
  __USE_GNU || !__GLIBC_USE (ISOC2X)), so if C2X features are enabled
  then those declarations (that are only in TS 18661-3 and not in C2X)
  will only be provided if _GNU_SOURCE is defined as well.  Thus
  _GNU_SOURCE remains a superset of the TS features as well as of C2X.

Some other somewhat related changes in C2X are not addressed here.
There's an open proposal not to include the fmin and fmax functions
for the _FloatN / _FloatNx types, given the new min/max operations,
which could be handled like the previous point if adopted.  And the
fromfp functions have been changed to return a result in floating type
rather than intmax_t / uintmax_t; my inclination there is to treat
that like that change of totalorder type (new symbol versions etc. for
the ABI change; old versions become compat symbols and are no longer
supported as an API).

Tested for x86_64 and x86.
2021-06-01 14:22:06 +00:00
H.J. Lu
94bc766ec6 Add cast_to_pointer to cast an integer to void * pointer 2021-05-22 05:09:15 -07:00
Florian Weimer
f47f1d91af nptl: Move pthread_create, thrd_create into libc
The symbols were moved using scripts/move-symbol-to-libc.py.

The libpthread placeholder symbols need some changes because some
symbol versions have gone away completely.  But
__errno_location@@GLIBC_2.0 still exists, so the GLIBC_2.0 version
is still there.

The internal __pthread_create symbol now points to the correct
function, so the sysdeps/nptl/thrd_create.c override is no longer
necessary.

There was an issue how the hidden alias of pthread_getattr_default_np
was defined, so this commit cleans up that aspects and removes the
GLIBC_PRIVATE export altogether.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-05-21 22:35:00 +02:00
Samuel Thibault
4d4bb451d5 hurd: Add execveat 2021-05-18 09:36:00 +00:00
Joseph Myers
e5ac7bd679 Add C2X timespec_getres
ISO C2X adds a timespec_getres function alongside the C11
timespec_get, with functionality similar to that of POSIX clock_getres
(including allowing a NULL pointer to be passed to the function).
Implement this function for glibc, similarly to the implementation of
timespec_get.

This includes a basic test like that of timespec_get, but no
documentation in the manual, given that TIME_UTC and timespec_get
aren't documented in the manual at all.  The handling of 64-bit time
follows that in timespec_get; people maintaining patch series for
64-bit time will need to update them accordingly (to export
__timespec_getres64, redirect calls in time.h and run the test for
_TIME_BITS=64).

Tested for x86_64 and x86, and (previous version; only testcase
differs) with build-many-glibcs.py.
2021-05-17 20:55:21 +00:00
Martin Sebor
c1760eaf3b Enable support for GCC 11 -Wmismatched-dealloc.
To help detect common kinds of memory (and other resource) management
bugs, GCC 11 adds support for the detection of mismatched calls to
allocation and deallocation functions.  At each call site to a known
deallocation function GCC checks the set of allocation functions
the former can be paired with and, if the two don't match, issues
a -Wmismatched-dealloc warning (something similar happens in C++
for mismatched calls to new and delete).  GCC also uses the same
mechanism to detect attempts to deallocate objects not allocated
by any allocation function (or pointers past the first byte into
allocated objects) by -Wfree-nonheap-object.

This support is enabled for built-in functions like malloc and free.
To extend it beyond those, GCC extends attribute malloc to designate
a deallocation function to which pointers returned from the allocation
function may be passed to deallocate the allocated objects.  Another,
optional argument designates the positional argument to which
the pointer must be passed.

This change is the first step in enabling this extended support for
Glibc.
2021-05-16 15:21:18 -06:00
Érico Nogueira
05ae46ee7a linux: implement ttyname as a wrapper around ttyname_r.
Big win in binary size and avoids duplicating the logic in multiple
places.

On x86_64, dropped from 1883206 to 1881790, a 1416 byte decrease.

Also changed logic to track if ttyname_buf has been allocated by
checking if it's NULL instead of tracking buflen as an additional
variable.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-05-07 13:56:02 -03:00
Adhemerval Zanella
903bc7dcc2 linux: Use sched_getaffinity for __get_nprocs (BZ #27645)
Both the sysfs and procfs parsing (through GET_NPROCS_PARSER) are
removed in favor the syscall.  The initial scratch buffer should
fit to most of the common usage (1024 bytes with maps to 8192 CPUs).

Checked on x86_64-linux-gnu and aarch64-linux-gnu.
2021-05-07 13:54:09 -03:00
Florian Weimer
f1af331c4e nptl: Move pthread_barrier_init into libc
The symbol was moved using scripts/move-symbol-to-libc.py.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-05-06 15:56:37 +02:00
Florian Weimer
0b7d48d106 nptl: Move sem_close, sem_open into libc
The symbols were moved using move-symbol-to-libc.py.

Both functions are moved at the same time because they depend
on internal functions in sysdeps/pthread/sem_routines.c, which
are moved in this commit as well.  Additional hidden prototypes
are required to avoid check-localplt failures.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-05-05 17:19:38 +02:00
Florian Weimer
fada901819 dlfcn: dlerror needs to call free from the base namespace [BZ #24773]
Calling free directly may end up freeing a pointer allocated by the
dynamic loader using malloc from libc.so in the base namespace using
the allocator from libc.so in a secondary namespace, which results in
crashes.

This commit redirects the free call through GLRO and the dynamic
linker, to reach the correct namespace.  It also cleans up the dlerror
handling along the way, so that pthread_setspecific is no longer
needed (which avoids triggering bug 24774).
2021-04-21 19:49:51 +02:00
Florian Weimer
1d95b035c7 nptl: Move __pthread_unwind_next into libc
It's necessary to stub out __libc_disable_asynccancel and
__libc_enable_asynccancel via rtld-stubbed-symbols because the new
direct references to the unwinder result in symbol conflicts when the
rtld exception handling from libc is linked in during the construction
of librtld.map.

unwind-forcedunwind.c is merged into unwind-resume.c.  libc now needs
the functions that were previously only used in libpthread.

The GLIBC_PRIVATE exports of __libc_longjmp and __libc_siglongjmp are
no longer needed, so switch them to hidden symbols.

The symbol __pthread_unwind_next has been moved using
scripts/move-symbol-to-libc.py.

Reviewed-by: Adhemerva Zanella  <adhemerval.zanella@linaro.org>
2021-04-21 19:49:50 +02:00
Fangrui Song
cd6ae7ea54 Set the retain attribute on _elf_set_element if CC supports [BZ #27492]
So that text_set_element/data_set_element/bss_set_element defined
variables will be retained by the linker.

Note: 'used' and 'retain' are orthogonal: 'used' makes sure the variable
will not be optimized out; 'retain' prevents section garbage collection
if the linker support SHF_GNU_RETAIN.

GNU ld 2.37 and LLD 13 will support -z start-stop-gc which allow C
identifier name sections to be GCed even if there are live
__start_/__stop_ references.

Without the change, there are some static linking problems, e.g.
_IO_cleanup (libio/genops.c) may be discarded by ld --gc-sections, so
stdout is not flushed on exit.

Note: GCC may warning 'retain' attribute ignored while __has_attribute(retain)
is 1 (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99587).

Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
2021-04-16 11:26:39 -07:00
Adhemerval Zanella
9d7c5cc38e linux: Normalize and return timeout on select (BZ #27651)
The commit 2433d39b69, which added time64 support to select, changed
the function to use __NR_pselect6 (or __NR_pelect6_time64) on all
architectures.  However, on architectures where the symbol was
implemented with __NR_select the kernel normalizes the passed timeout
instead of return EINVAL.  For instance, the input timeval
{ 0, 5000000 } is interpreted as { 5, 0 }.

And as indicated by BZ #27651, this semantic seems to be expected
and changing it results in some performance issues (most likely
the program does not check the return code and keeps issuing
select with unormalized tv_usec argument).

To avoid a different semantic depending whether which syscall the
architecture used to issue, select now always normalize the timeout
input.  This is a slight change for some ABIs (for instance aarch64).

Checked on x86_64-linux-gnu and i686-linux-gnu.
2021-04-12 18:38:37 -03:00
Adhemerval Zanella
4c8cb283ec nptl: Remove pwrite from libpthread
The libc version is identical and built with same flags, it is also
uses as the default version.

Checked on x86_64-linux-gnu.
2021-03-26 13:37:18 -03:00
Adhemerval Zanella
dd795c6c24 nptl: Remove pread from libpthread
The libc version is identical and built with same flags, it is also
uses as the default version.

Checked on x86_64-linux-gnu.
2021-03-26 13:37:18 -03:00
Adhemerval Zanella
c5c3588475 nptl: Remove lseek from libpthread
The libc version is identical and built with same flags.  The libc
version is set as the default version.

The libpthread compat symbol requires to mask it when building the
loader object otherwise ld might complain about a missing
versioned symbol (as for alpha).

Checked on x86_64-linux-gnu.
2021-03-26 13:36:17 -03:00
Adhemerval Zanella
4d2e9ef806 Add OTHER_SHLIB_COMPAT
It is similar to SHLIB_COMPAT, but allows to check versions from
other libraries.  It is used to move compat symbol from other libraries
to libc.
2021-03-26 13:36:16 -03:00
Szabolcs Nagy
0ae773bba0 malloc: Move MTAG_MMAP_FLAGS definition
This is only used internally in malloc.c, the extern declaration
was wrong, __mtag_mmap_flags has internal linkage.

Reviewed-by: DJ Delorie <dj@redhat.com>
2021-03-26 11:03:06 +00:00
Florian Weimer
0923f74ada Support for multiple versions in versioned_symbol, compat_symbol
This essentially folds compat_symbol_unique functionality into
compat_symbol.

This change eliminates the need for intermediate aliases for defining
multiple symbol versions, for both compat_symbol and versioned_symbol.
Some binutils versions do not suport multiple versions per symbol on
some targets, so aliases are automatically introduced, similar to what
compat_symbol_unique did.  To reduce symbol table sizes, a configure
check is added to avoid these aliases if they are not needed.

The new mechanism works with data symbols as well as function symbols,
due to the way an assembler-level redirect is used.  It is not
compatible with weak symbols for old binutils versions, which is why
the definition of __malloc_initialize_hook had to be changed.  This
is not a loss of functionality because weak symbols do not matter
to dynamic linking.

The placeholder symbol needs repeating in nptl/libpthread-compat.c
now that compat_symbol is used, but that seems more obvious than
introducing yet another macro.

A subtle difference was that compat_symbol_unique made the symbol
global automatically.  compat_symbol does not do this, so static
had to be removed from the definition of
__libpthread_version_placeholder.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-03-25 12:33:02 +01:00