Source packages that need to support both 2.19 and
2.20 will need to decide to use _BSD_SOURCE and
_SVID_SOURCE vs. _DEFAULT_SOURCE.
The difficulty in making that decision is that
__GLIBC_MINOR__ is itself defined in features.h,
but you want to set the feature test macros before
including features.h.
Therefore to ease the transition we should disable
the warning if _DEFAULT_SOURCE is also defined.
https://sourceware.org/ml/libc-alpha/2014-02/msg00666.htmlhttps://sourceware.org/glibc/wiki/Release/2.20#Packaging_Changes
This is a minimal patch to remove _BSD_SOURCE and _SVID_SOURCE from
the documented user API, making them into aliases for _DEFAULT_SOURCE
with a #warning given, but keeping most of the features.h logic using
those macros and all the exising __USE_* conditionals, on the basis
that all the consequent cleanups will go in followup patches.
Tested x86_64.
* include/features.h: Update comment documenting feature test
macros.
[_BSD_SOURCE || _SVID_SOURCE]: Give #warning. Define
_DEFAULT_SOURCE.
* manual/creature.texi (_BSD_SOURCE): Remove documentation.
(_SVID_SOURCE): Likewise.
(_DEFAULT_SOURCE): Update description of default features.
(Feature Test Macros): Don't mention _SVID_SOURCE in conjunction
with _GNU_SOURCE.
* manual/filesys.texi (__ftw_func_t): Do not refer to _BSD_SOURCE.
(S_ISVTX): Likewise.
* manual/math.texi (Mathematical Constants): Likewise.
* manual/signal.texi (Interrupted Primitives): Likewise.
* manual/startup.texi (putenv): Do not refer to _SVID_SOURCE.
* math/test-matherr.c (_SVID_SOURCE): Do not define.
* sysvipc/sys/ipc.h [__USE_SVID && !__USE_XOPEN && __GNUC__ >= 2]:
Don't refer to _SVID_SOURCE in warning text.
Add a comment pointing to the SystemTap wiki page that documents the
format of the arguments. Also add a pointer to the SystemTap and
gdb sources which seem to be the best place to get the architecture
specific details.
ChangeLog:
2014-02-11 Will Newton <will.newton@linaro.org>
* include/stap-probe.h: Add comment about probe argument
format.
This patch adds a feature test macro _DEFAULT_SOURCE to enable the
default set of header declarations.
The intention is: if _DEFAULT_SOURCE is not used there is no change to
the set of __USE_* macros glibc defines; if it's used on its own, and
without compiler options such as -std=c99 that define __STRICT_ANSI__,
again, there is no change; if it's used together with the macros it
approximately (i.e., apart from __USE_POSIX_IMPLICITLY) implies
(-D_BSD_SOURCE -D_SVID_SOURCE -D_POSIX_C_SOURCE=200809L), again, there
is no change. Otherwise, it causes the relevant features to be
enabled, even if __STRICT_ANSI__, or another feature test macro, would
cause them to be disabled.
This macro deliberately bundles the POSIX.1-2008 (non-X/Open)
functionality with the BSD/SVID/"misc" functionality, rather than
defining a macro that gives just the latter, as many of the header
cleanups resulting from removing _BSD_SOURCE and _SVID_SOURCE support
are only possible when BSD/SVID/"misc" is always bundled with
POSIX.1-2008.
Tested x86_64.
* include/features.h: Update comment documenting feature test
macros. Mention _DEFAULT_SOURCE in comment.
[_GNU_SOURCE] (_DEFAULT_SOURCE): Undefine and redefine.
[_DEFAULT_SOURCE]: Undefine and redefine _DEFAULT_SOURCE,
_BSD_SOURCE and _SVID_SOURCE.
[!__STRICT_ANSI__ && !_ISOC99_SOURCE && !_POSIX_SOURCE &&
!_POSIX_C_SOURCE && !_XOPEN_SOURCE && !_BSD_SOURCE &&
!_SVID_SOURCE]: Likewise.
[_DEFAULT_SOURCE && !_POSIX_SOURCE && !_POSIX_C_SOURCE]
(__USE_POSIX_IMPLICITLY): Define.
[_DEFAULT_SOURCE && !_POSIX_SOURCE && !_POSIX_C_SOURCE]
(_POSIX_SOURCE): Undefine and redefine.
[_DEFAULT_SOURCE && !_POSIX_SOURCE && !_POSIX_C_SOURCE]
(_POSIX_C_SOURCE): Likewise.
* manual/creature.texi (_DEFAULT_SOURCE): Document.
(Feature Test Macros): Update documentation of default features.
Joseph pointed out in the bug report (and in an earlier thread) that
systemtap probes cause build time warnings like the following:
../sysdeps/ieee754/dbl-64/e_atan2.c:602:4: warning: the address of
'p' will always evaluate as 'true' [-Waddress]
due to the fact that we're now passing non-weak variables to
LIBC_PROBE in the libm probes. This happens only on configurations
that do not enable systemtap. The macro definition of LIBC_PROBE in
this case only acts as a sanity checker to ensure that the number
parameters passed to LIBC_PROBE is equal to the argument count
parameter passed before it. This can be done in a much simpler manner
by just adding a macro definition for each number of arguments. I am
assuming here that we don't really want to bother with supporting
LIBC_PROBE with an indeterminate number of arguments and if there is a
need for a probe to have more data than what is currently supported (4
arguments), one could simply add an additional macro here.
Rather than open coding the masks, add helper macros to do the magic.
This makes code easier to read.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Check wheter the compiler has the option -fno-tree-loop-distribute-patterns
to inhibit loop transformation to library calls and uses it on memset
and memmove default implementation to avoid recursive calls.
The most common use case of math functions is with default rounding
mode, i.e. rounding to nearest. Setting and restoring rounding mode
is an unnecessary overhead for this, so I've added support for a
context, which does the set/restore only if the FP status needs a
change. The code is written such that only x86 uses these. Other
architectures should be unaffected by it, but would definitely benefit
if the set/restore has as much overhead relative to the rest of the
code, as the x86 bits do.
Here's a summary of the performance improvement due to these
improvements; I've only mentioned functions that use the set/restore
and have benchmark inputs for x86_64:
Before:
cos(): ITERS:4.69335e+08: TOTAL:28884.6Mcy, MAX:4080.28cy, MIN:57.562cy, 16248.6 calls/Mcy
exp(): ITERS:4.47604e+08: TOTAL:28796.2Mcy, MAX:207.721cy, MIN:62.385cy, 15543.9 calls/Mcy
pow(): ITERS:1.63485e+08: TOTAL:28879.9Mcy, MAX:362.255cy, MIN:172.469cy, 5660.86 calls/Mcy
sin(): ITERS:3.89578e+08: TOTAL:28900Mcy, MAX:704.859cy, MIN:47.583cy, 13480.2 calls/Mcy
tan(): ITERS:7.0971e+07: TOTAL:28902.2Mcy, MAX:1357.79cy, MIN:388.58cy, 2455.55 calls/Mcy
After:
cos(): ITERS:6.0014e+08: TOTAL:28875.9Mcy, MAX:364.283cy, MIN:45.716cy, 20783.4 calls/Mcy
exp(): ITERS:5.48578e+08: TOTAL:28764.9Mcy, MAX:191.617cy, MIN:51.011cy, 19071.1 calls/Mcy
pow(): ITERS:1.70013e+08: TOTAL:28873.6Mcy, MAX:689.522cy, MIN:163.989cy, 5888.18 calls/Mcy
sin(): ITERS:4.64079e+08: TOTAL:28891.5Mcy, MAX:6959.3cy, MIN:36.189cy, 16062.8 calls/Mcy
tan(): ITERS:7.2354e+07: TOTAL:28898.9Mcy, MAX:1295.57cy, MIN:380.698cy, 2503.7 calls/Mcy
So the improvements are:
cos: 27.9089%
exp: 22.6919%
pow: 4.01564%
sin: 19.1585%
tan: 1.96086%
The downside of the change is that it will have an adverse performance
impact on non-default rounding modes, but I think the tradeoff is
justified.
__clock_gettime and other __clock_* functions could result in an extra
PLT reference within libc.so if it actually gets used. None of the
code currently uses them, which is why this probably went unnoticed.
Since we want to use this in installed headers, move it to the installed
sys/cdefs.h. This requires a slight tweaking of the name (add trailing
underscores).
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
These prototypes are duplicated in many places. Add a dedicated
header for holding prototypes for program-specific functions to
avoid that.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
This feature is specifically for the C++ compiler to offload calling
thread_local object destructors on thread program exit, to glibc.
This is to overcome the possible complication of destructors of
thread_local objects getting called after the DSO in which they're
defined is unloaded by the dynamic linker. The DSO is marked as
'unloadable' if it has a constructed thread_local object and marked as
'unloadable' again when all the constructed thread_local objects
defined in it are destroyed.
These internal knobs are not exposed as part of the public ABI, so mark
them hidden to avoid generating relocations against them.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
We can't assume sock_cloexec and pipe2 are bound together as the former
defines are found in glibc only while the latter are a combo of kernel
headers and glibc. So if we do a runtime detection of SOCK_CLOEXEC, but
pipe2() is a stub inside of glibc, we hit a problem. For example:
main()
{
getgrnam("portage");
if (!popen("ls", "r"))
perror("popen()");
}
getgrnam() will detect that the kernel supports SOCK_CLOEXEC and then set
both __have_sock_cloexec and __have_pipe2 to true. But if glibc was built
against older kernel headers where __NR_pipe2 does not exist, glibc will
have a ENOSYS stub for it. So popen() will always fail as glibc assumes
pipe2() works.
While this isn't too much of an issue for some arches as they added the
functionality to the kernel at the same time, not all arches are that
lucky.
Since the code already has dedicated names for each feature, delete the
defines wiring these three features together and make each one a proper
dedicated knob.
We've been carrying this in Gentoo since glibc-2.9.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
[BZ #13579] Do not free l_initfini and allow it to be reused
on subsequent dl_open calls for the same library. This fixes
the invalid memory access in do_lookup_x when the previously
free'd l_initfini was accessed through l_searchlist when a
library had been opened for the second time.
New configure option --enable-obsolete-rpc makes the deprecated RPC
headers and functions available at compile time as they were before
version 2.14. This option will be removed at some time in the future
after the TI-RPC library becomes fully sufficient for the needs of
existing applications.
Whenever getaddrinfo needed network interface information it used the
netlink interface to read the information every single time. The
problem is that this information can change at any time.
The patch implements monitoring of the network interfaces through
nscd. If no change is detected the previously read information can
be reused (which is the norm). This timestamp information is also
made available to other processes using the shared memory segment
between nscd and those processes.
fopen should set the FD_CLOEXEC flag if requested evenif the kernel does
not support an aotmic operation.
freopen should reuse the file descriptor for the stream. This is
especially important for calls to change the standard streams (stin,
stdout, stderr).
The getcwd syscall (so far?) can only handle path up to one page
in size. There is no limit about directory hierarchy depth, though,
and the POSIX getcwd is supposed to handle this. In that case fall
back to the generic getcwd.
Additionally, optimize the generic getcwd to use openat when possible
to change the asymptotic performance from O(N^2) to O(n).
Like the real header, the libc-internal wrapper for wchar.h needs to
undefine the macros so that if the header was already included before
the macros don't stay defined and cause problems later.
The old implementation uses fd 0 to determine the login TTY. This
was needed because using /dev/tty it is not possible to deduce the
login TTY. For some time now there is the pseudo-file
/proc/self/loginuid which directly helps us to find the user. Prefer
using this file. It also works if stdin is closed, redirected, or
re-opened.
On some architectures the update of the l_used field in the lookup
functions races with setting the other bits in the bitfield. Simply
avoid this and optimize use of l_used in general.
grantpt was performing two consecutive calls to stat with the same
file name. Avoid this by creating a special version of the ptsname
function which allows to pass the stat result back to the caller.
We use a callback function into libc.so to get access to the data
structure with the information and have special versions of the test
macros which automatically use this function.
The following patch fixes catomic_compare_and_exchange_*_rel definitions
(which were never used and weren't correct) and uses
catomic_compare_and_exchange_val_rel in _int_free. Comparing to the
pre-2009-07-02 --enable-experimental-malloc state the generated code should
be identical on all arches other than ppc/ppc64 and on ppc/ppc64 should use
lwsync instead of isync barrier.
The terminal output etc is not visible in a core file. The new
libc-internal variable __abort_msg will point to a string with the
message which has been printed before the abort in case abort is
called from inside libc. BZ #10217
If longjmp restores the stack frame to an address which is beyond
the stack frame at the time of the longjmp call it would install
an uninitialized stack frame. If compiled with _FORTIFY_SOURCE
defined, longjmp will now bail out in this situation.
* sysdeps/unix/sysv/linux/bits/stat.h: Protect UTIME_NOW and
UTIME_OMIT only with __USE_ATFILE.
* sysdeps/unix/sysv/linux/ia64/bits/stat.h: Likewise.
* sysdeps/unix/sysv/linux/powerpc/bits/stat.h: Likewise.
* sysdeps/unix/sysv/linux/s390/bits/stat.h: Likewise.
* sysdeps/unix/sysv/linux/sparc/bits/stat.h: Likewise.
* sysdeps/unix/sysv/linux/x86_64/bits/stat.h: Likewise.
* io/sys/stat.h: Move mknodat definition into same conditional as
mknod.
* time/sys/time.h: futimesat is not among the functions accepted
into the POSIX standard.
by default a POSIX mode, also define __USE_POSIX_IMPLICITLY.
* posix/Versions: Export __posix_getopt.
* posix/getopt.c (_getopt_initialize): Take additional parameter.
Use it to alternatively initialize __posixly_correct.
(_getopt_internal_r): Take addition parameter. Pass on to
_getopt_initialize.
(_getopt_internal): Take addition parameter. Pass on to
_getopt_internal_r.
(getopt): Pass additional zero to _getopt_internal.
(__posix_getopt): New function.
* posix/getopt.h: Add redirection for getopt.
* posix/getopt1.c (getopt_long): Pass additional zero to
_getopt_internal.
(getopt_long_only): Likewise.
(_getopt_long_r): Pass additional zero to _getopt_internal_r.
(_getopt_long_only_r): Likewise.
* posix/getopt_int.h: Adjust declarations of _getopt_internal and
_getopt_internal_r.
Change all callers.
(_int_realloc): Likewise.
All _int_* functions are now static.
* malloc/hooks.c: Change all callers to _int_free and _int_realloc.
* malloc/arena.c: Likewise.
* include/malloc.h: Remove now unnecessary declarations of the _int_*
functions.
* nscd/mem.c (gc): Use alloca_count to get the real stack usage.
* include/alloca.h (alloca_account): Define.
* sysdeps/x86_64/stackinfo.h (stackinfo_get_sp): Define.
(stackinfo_sub_sp): Define.
* include/resolv.h: Remove hidden proto declarations for __ns_*
functions. Add them for __dn_count_labels and __p_secstodate.
* include/arpa/nameser.h: Add a number of hidden proto declarations.
Define ns_msg_getflags macro here.
* resolv/res_debug.c: Add hidden definition for __dn_count_labels
and __p_secstodate.
* resolv/Versions: Export functions from <arpa/nameser.h> from
libresolv in version GLIBC_2.9.
* resolv/ns_name.c: Integrate changes from bind 9.5.0. Add necessary
hidden definitions.
* resolv/ns_netint.c: Likewise.
* resolv/ns_parse.c: Likewise.
* resolv/ns_print.c: Likewise.
* resolv/ns_samedomain.c: Likewise.
* resolv/ns_ttl.c: Likewise.
* resolv/arpa/nameser_compat.h: Likewise.
* resolv/arpa/nameser.h: Likewise. Remove macros which redirect
function calls.
* resolv/nss_dns/dns-canon.c (_nss_dns_getcanonname_r): Use __ns_get16
instead of ns_get16.
* resolv/nss_dns/dns-host.c (getanswer_r): Use __ns_get16 and
__ns_get32 instead of ns_get16 and ns_get32 respectively.
(gaih_getanswer_slice): Likewise.
* resolv/Makefile (libresolv-routines): Add ns_date.
* resolv/ns_date.c: New file.
Use it instead of locally defined resplen2 variable.
(res_nsend): Adjust for __libc_res_nsend interface change.
(send_vc): Initialize *resplen2 if necessary. Read length of
package into an appropriately aligned variable. Store converted length
in new variable and use it appropriately.
Add branch prediction help.
* resolv/res_query.c (__libc_res_nquery): Take additional parameter
and pass it on to __libc_res_nsend. Adjust all callers.
(__libc_res_nsearch): Likewise.
(__libc_res_nqeurydomain): Likewise.
* resolv/nss_dns/dns-host.c: Adjust for __libc_res_nsearch interface
change.
(_nss_dns_gethostbyname4): Don't unconditionally allocate tmp array.
Define resplen2 variable and pass it to __libc_res_nsearch and then
to gaih_getanswer.
(getanswer_r): In case of incorrect DNS data don't overread buffer.
Add branch prediction.
(gaih_getanswer_slice): Likewise. Check for invalid data types.
(gaih_getanswer): Don't decode second slice if first one failed due
to a too small buffer. Don't let not found status of second
decoder shadow results of the first.
* resolv/gethnamaddr.c (gethostbyname2): Adjust for __libc_res_nsearch
and __libc_res_nquery interface changes
(gethostbyaddr): Adjust for __libc_res_nquery interface change.
* include/resolv.h: Adjust prototypes for __libc_res_nquery,
__libc_res_nsearch, and __libc_res_nsend.
* resolv/nss_dns/dns-canon.c: Adjust for __libc_res_nquery interface
change.
* resolv/nss_dns/dns-network.c: Adjust for __libc_res_nquery and
__libc_res_nsearch interface changes.
__libc_clntudp_bufcreate_internal.
* include/sys/socket.h: Declare __have_sock_cloexec.
* socket/Makefile (aux): Add have_sock_cloexec.
* socket/have_sock_cloexec.c: New file.
* sunrpc/clnt_udp.h (clntudp_bufcreate): Now a wrapper around
__libc_clntudp_bufcreate.
(__libc_clntudp_bufcreate): Former implementation of clntudp_bufcreate
which takes an additional parameter. Create socket with non-blocking
mode and close-on-exec flag set, if wanted.
* sunrpc/Versions: Export __libc_clntudp_bufcreate@GLIBC_PRIVATE.
* nis/ypclnt.c (yp_bind_client_create): Use __libc_clntpudp_bufcreate
instead of clntudp_create. The socket has already the close-on-exec
flag set if SOCK_CLOEXEC is defined.
prototypes.
* include/arpa/nameser_compat.h: Define T_UNSPEC.
* nis/Versions (libnss_nis): Export _nss_nis_gethostbyname4_r.
(libnss_nisplus): Export _nss_nisplus_gethostbyname4_r.
* nis/nss_nis/nis-hosts.c (LINE_PARSER): Change to also handle
af==AF_UNSPEC.
(_nss_nis_gethostbyname4_r): New function.
* nis/nss_nisplus/nisplus-hosts.c (_nss_nisplus_parse_hostent):
Change to also handle af==AF_UNSPEC.
(get_tablename): New function. Use it to avoid duplication.
(_nss_nisplus_gethostbyname4_r): New function.
* nscd/aicache.c (addhstaiX): Use gethostbyname4_r function is
available.
* nss/Versions (libnss_files): Export _nss_files_gethostbyname4_r.
* nss/nss.h: Define struct gaih_addrtuple.
* nss/nss_files/files-hosts.c (LINE_PARSER): Change to also handle
af==AF_UNSPEC.
(_nss_files_gethostbyname4_r): New function.
* resolv/Versions (libnss_dns): Export _nss_dns_gethostbyname4_r.
* resolv/gethnmaddr.c: Adjust __libc_res_nsearch and __libc_res_nquery
calls.
* resolv/res_query.c (__libc_res_nquery): Take two additional
parameters for second answer buffer. Handle type=T_UNSPEC to mean
look up IPv4 and IPv6.
Change all callers.
* resolv/res_send.c (__libc_res_nsend): Take five aditional parameters
for an additional query and answer buffer. Pass to send_vc and
send_dg.
(send_vc): Send possibly two requests and receive two answers.
(send_dg): Likewise.
* resolv/nss_dns/dns-host.c: Adjust calls to __libc_res_nsearch and
__libc_res_nquery.
(_nss_dns_gethostbyname4_r): New function.
(gaih_getanswer_slice): Likewise.
(gaih_getanswer): Likewise.
* resolv/nss_dns/dns-canon.c (_nss_dns_getcanonname_r): Adjust
__libc_res_nquery call.
* resolv/nss_dns/dns-network.c (_nss_dns_getnetbyaddr_r): Likewise.
(_nss_dns_getnetbyname_r): Adjust __libc_res_nsearch call.
* sysdeps/posix/getaddrinfo.c: Use gethostbyname4_r function is
available.
__fe_nomask_env.
* sysdeps/powerpc/fpu/fe_nomask.c: Add libm_hidden_def.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/fe_nomask.c: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/fpu/fe_nomask.c: Likewise.
* sysdeps/powerpc/bits/fenv.h: Make safe for C++.
* sysdeps/unix/sysv/linux/powerpc/bits/mathinline.h: New file.
* sysdeps/powerpc/fpu/fegetexcept.c (__fegetexcept): Rename
function from fegetexcept and make old name weak alias.
* include/fenv.h: Declare __fegetexcept.
* sysdeps/powerpc/fpu/fedisblxcpt.c: Use __fegetexcept instead of
fegetexcept.
* sysdeps/powerpc/fpu/feenablxcpt.c: Likewise.
* sysdeps/powerpc/fpu/fraiseexcpt.c (__feraiseexcept): Avoid call
to fetestexcept.
* sysdeps/ieee754/ldbl-128ibm/s_log1pl.c (__log1pl): Use __frexpl
instead of frexpl to avoid local PLT.
* math/s_significandl.c (__significandl): Use __ilogbl instead of
ilogbl to avoid local PLT.
* sysdeps/ieee754/ldbl-128ibm/s_expm1l.c (__expm1l): Use __ldexpl
instead of ldexpl to avoid local PLT.
* sysdeps/ieee754/ldbl-128ibm/e_expl.c (__ieee754_expl): Use
__roundl not roundl to avoid local PLT.
* sysdeps/ieee754/ldbl-128/e_j0l.c: Use function names which avoid
local PLTs. Use __sincosl instead of separate sinl and cosl
calls.
* sysdeps/ieee754/ldbl-128/e_j1l.c: Likewise.
* elf/dl-close.c (_dl_close): Check for it.
* elf/dl-reloc.c (CHECK_STATIC_TLS): Likewise.
(_dl_allocate_static_tls): Likewise.
* elf/dl-tls.c (_dl_allocate_tls_init): Likewise.
(__tls_get_addr): Protect from race conditions in setting l_tls_offset
to it.
* elf/tst-tls16.c: New file.
* elf/tst-tlsmod16a.c: New file.
* elf/tst-tlsmod16b.c: New file.
* elf/Makefile: Add rules to build and run tst-tls16.
(struct in6addrinfo): Add index element.
Declare __check_native.
* inet/Makefile (aux): Add check_native.
* sysdeps/unix/sysv/linux/check_native.c: New file.
* sysdeps/unix/sysv/linux/check_pf.c: No need to recognize
IFA_F_TEMPORARY. Pass back ifa_index.
* sysdeps/posix/getaddrinfo.c: Remove netlink compatibility code.
(rfc3484_sort): Add new parameter. Implement rule 7 correctly:
call __check_native if necessary.
(getaddrinfo): Fill in index field. Use qsort_r instead of qsort
to sort addresses. Pass information about the results.
* posix/tst-rfc3484.c: Adjust for addition of index field and change
of rfc3484_sort interface.
* posix/tst-rfc3484-2.c: Likewise.
* include/stdlib.h: Add hidden_proto for qsort_t and adjust protoype
for _quicksort.
* stdlib/msort.c (qsort): Now a wrapper around qsort_r.
(qsort_r): Renamed from qsort. Take additional parameter and pass it
on as third parameter to compare function and _quicksort.
* stdlib/qsort.c (_quicksort): Take additional parameter and pass on
to the compare function.
* stdlib/Versions [libc] (GLIBC_2.8): Add qsort_r.
* Versions.def: Add GLIBC_2.8 for libc.