TS 18661-1 defines an fetestexceptflag function to test the exception
state saved in an fexcept_t object by fegetexceptflag.
This patch implements this function for glibc. Almost all
architectures save exception state in such a way that it can be
directly ANDed with exception flag bits, so rather than having lots of
fetestexceptflag implementations that all do the same thing, the math/
implementation is made to use this generic logic (which is also OK in
the fallback case where FE_ALL_EXCEPT is zero). The only architecture
that seems to need anything different is s390.
(fegetexceptflag and fesetexceptflag use abbreviated filenames
fgetexcptflg.c and fsetexcptflg.c. Because we are no longer concerned
by 14-character filename limits, fetestexceptflag uses the obvious
filename fetestexceptflag.c.)
The NEWS entry is intended to be expanded along the lines given in
<https://sourceware.org/ml/libc-alpha/2016-08/msg00356.html> when
fegetmode and fesetmode are added.
Tested for x86_64, x86, mips64 and powerpc.
* math/fetestexceptflag.c: New file.
* sysdeps/s390/fpu/fetestexceptflag.c: Likewise. Comment by
Stefan Liebler.
* math/fenv.h [__GLIBC_USE (IEC_60559_BFP_EXT)]
(fetestexceptflag): New function declaration.
* manual/arith.texi (fetestexceptflag): Document function.
* math/Versions (fetestexceptflag): New libm symbol at version
GLIBC_2.25.
* math/Makefile (libm-support): Add fetestexceptflag.
(tests): Add test-fetestexceptflag.
* math/test-fetestexceptflag.c: New file.
* sysdeps/nacl/libm.abilist: Update.
* sysdeps/unix/sysv/linux/aarch64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/alpha/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/arm/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/hppa/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/i386/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/ia64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/m68k/coldfire/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/m68k/m680x0/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/microblaze/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/nios2/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libm.abilist:
Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libm.abilist:
Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/libm-le.abilist:
Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/libm.abilist:
Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/sh/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc32/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/tile/tilegx/tilegx32/libm.abilist:
Likewise.
* sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/libm.abilist:
Likewise.
* sysdeps/unix/sysv/linux/tile/tilepro/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/x86_64/64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/x86_64/x32/libm.abilist: Likewise.
TS 18661-1 defines an fesetexcept function for setting floating-point
exception flags without the side-effect of causing enabled traps to be
taken.
This patch series implements this function for glibc. The present
patch adds the fallback stub implementation, x86 and x86_64
implementations, documentation, tests and ABI baseline updates. The
remaining patches, some of them untested, add implementations for
other architectures. The implementations generally follow those of
the fesetexceptflag function.
As for fesetexceptflag, the approach taken for architectures where
setting flags causes enabled traps to be taken is to set the flags
(and potentially cause traps) rather than refusing to set the flags
and returning an error. Since ISO C and TS 18661 provide no way to
enable traps, this is formally in accordance with the standards.
The NEWS entry should be considered a placeholder, since this patch
series is intended to be followed by further such series adding other
TS 18661-1 features, so that the NEWS entry would end up looking more
like
* New <fenv.h> features from TS 18661-1:2014 are added to libm: the
fesetexcept, fetestexceptflag, fegetmode and fesetmode functions,
the femode_t type and the FE_DFL_MODE macro.
with hopefully more such entries for other features, rather than
having an entry for a single function in the end.
I believe we have consensus for adding TS 18661-1 interfaces as per
<https://sourceware.org/ml/libc-alpha/2016-06/msg00421.html>.
Tested for x86_64, x86, mips64 (hard float, and soft float to test the
fallback version), arm (hard float) and powerpc (hard float, soft
float and e500).
* math/fesetexcept.c: New file.
* sysdeps/i386/fpu/fesetexcept.c: Likewise.
* sysdeps/x86_64/fpu/fesetexcept.c: Likewise.
* math/fenv.h: Define
__GLIBC_INTERNAL_STARTING_HEADER_IMPLEMENTATION and include
<bits/libc-header-start.h> instead of including <features.h>.
[__GLIBC_USE (IEC_60559_BFP_EXT)] (fesetexcept): New function
declaration.
* manual/arith.texi (fesetexcept): Document function.
* math/Versions (fesetexcept): New libm symbol at version
GLIBC_2.25.
* math/Makefile (libm-support): Add fesetexcept.
(tests): Add test-fesetexcept and test-fesetexcept-traps.
* math/test-fesetexcept.c: New file.
* math/test-fesetexcept-traps.c: Likewise.
* sysdeps/nacl/libm.abilist: Update.
* sysdeps/unix/sysv/linux/aarch64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/alpha/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/arm/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/hppa/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/i386/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/ia64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/m68k/coldfire/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/m68k/m680x0/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/microblaze/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/nios2/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libm.abilist:
Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libm.abilist:
Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/libm-le.abilist:
Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/libm.abilist:
Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/sh/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc32/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/tile/tilegx/tilegx32/libm.abilist:
Likewise.
* sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/libm.abilist:
Likewise.
* sysdeps/unix/sysv/linux/tile/tilepro/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/x86_64/64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/x86_64/x32/libm.abilist: Likewise.
This patch implements support for the
__STDC_WANT_IEC_60559_FUNCS_EXT__ feature test macro, following the
__GLIBC_USE approach used for other ISO C feature test macros.
Currently this only affects the exp10 functions (which glibc has had
for a long time).
Tested for x86_64 and x86 (testsuite, and that installed stripped
shared libraries are unchanged by the patch).
* bits/libc-header-start.h (__GLIBC_USE_IEC_60559_FUNCS_EXT): New
macro.
* include/features.h (__STDC_WANT_IEC_60559_FUNCS_EXT__):
Document.
* manual/creature.texi (__STDC_WANT_IEC_60559_FUNCS_EXT__):
Document macro.
* manual/math.texi (exp10): Document as ISO from TS 18661-4:2015.
(exp10f): Likewise.
(exp10l): Likewise.
* math/bits/mathcalls.h (exp10): Declare if
[__GLIBC_USE (IEC_60559_FUNCS_EXT)], not [__USE_GNU].
The macros defined by <sys/sysmacros.h> are not part of POSIX nor XSI, and
their names frequently collide with user code; see for instance glibc bug
19239 and Red Hat bug 130601. <stdlib.h> includes <sys/types.h> under
_GNU_SOURCE, and C++ code presently cannot avoid being compiled under
_GNU_SOURCE, exacerbating the problem.
* NEWS: Inclusion of <sys/sysmacros.h> by <sys/types.h> is deprecated.
* misc/sys/sysmacros.h: If __SYSMACROS_DEPRECATED_INCLUSION is defined,
define major, minor, and makedev to issue deprecation warnings on use.
If __SYSMACROS_DEPRECATED_INCLUSION is *not* defined, suppress
previously-activated deprecation warnings for these macros and prevent
subsequent inclusions of this header from having any effect.
* posix/sys/types.h: Define __SYSMACROS_DEPRECATED_INCLUSION before
including <sys/sysmacros.h>, and undefine it again afterward.
This patch implements support for the __STDC_WANT_IEC_60559_BFP_EXT__
feature test macro from ISO/IEC 18661-1:2014, following the
__GLIBC_USE approach now used for __STDC_WANT_LIB_EXT2__. For this
macro, the relevant consideration is whether it is defined or
undefined when an affected header is included (not what its value is
if defined, and not whether it's defined or undefined when any other
unaffected system header is included).
Currently this macro only affects the issignaling macro and the nextup
and nextdown functions (so they can be enabled by defining this macro,
not just by defining _GNU_SOURCE as previously). Any further features
from this TS added in future would also be conditioned on this macro.
Tested for x86_64 and x86 (testsuite, and that installed stripped
shared libraries are unchanged by the patch).
* bits/libc-header-start.h (__GLIBC_USE_IEC_60559_BFP_EXT): New
macro.
* include/features.h (__STDC_WANT_IEC_60559_BFP_EXT__): Document.
* manual/arith.texi (issignaling): Document as ISO from TS
18661-1:2014.
(nextup): Likewise.
(nextupf): Likewise.
(nextupl): Likewise.
(nextdown): Likewise.
(nextdownf): Likewise.
(nextdownl): Likewise.
* manual/creature.texi (__STDC_WANT_IEC_60559_BFP_EXT__): Document
macro.
* math/math.h: Define
__GLIBC_INTERNAL_STARTING_HEADER_IMPLEMENTATION and include
<bits/libc-header-start.h> instead of including <features.h>.
(issignaling): Define if [__GLIBC_USE (IEC_60559_BFP_EXT)], not
[__USE_GNU].
* math/bits/mathcalls.h (nextdown): Declare if
[__GLIBC_USE (IEC_60559_BFP_EXT)], not [__USE_GNU].
(nextup): Likewise.
(__issignaling): Likewise.
This patch implements support for the __STDC_WANT_LIB_EXT2__ feature
test macro from ISO/IEC TR 24731-2:2010, thereby implementing one
possible approach for supporting ISO C feature test macros.
Recall that, as described in
<https://sourceware.org/ml/libc-alpha/2016-05/msg00486.html>, these
macros work based on the definition when affected headers are
included, so cannot be handled once when the first system header is
included because that might not be one of the headers the particular
macro in question affects.
<https://sourceware.org/ml/libc-alpha/2016-05/msg00680.html> expresses
views on possible approaches for implementation and
<https://sourceware.org/ml/libc-alpha/2016-06/msg00039.html> follows
up on that.
This patch arranges things so that the relevant condition is
__GLIBC_USE (LIB_EXT2), following one of the suggestions given.
Headers using these macros include <bits/libc-header-start.h>, which
in turn includes <features.h>. Headers must define
__GLIBC_INTERNAL_STARTING_HEADER_IMPLEMENTATION before including
<bits/libc-header-start.h>, to discourage inclusion outside glibc as
requested. __USE_GNU conditions on affected functions are changed to
__GLIBC_USE (LIB_EXT2), while it's added as an additional alternative
on the conditions for functions already enabled for some POSIX
versions.
It would be possible to convert existing __USE_* conditionals to
__GLIBC_USE (with the relevant __GLIBC_USE_* being defined in
<features.h> where __USE_* are presently defined), and so make them
typo-proof (given -Wundef -Werror in glibc builds) because __GLIBC_USE
is used with #if not #ifdef / #if defined.
No attempt is made to enforce the rule about diagnosing different
definitions of __STDC_WANT_LIB_EXT2__ when affected headers are
included; such a diagnostic is incompatible with multiple-include
guards on the affected headers, unless compiler extensions are added
to support it.
As previously noted, glibc does not implement all features from TR
24731-2:2010: the functions aswprintf vaswprintf getwdelim getwline
are not in glibc, although they would be appropriate to add if someone
wished to do so. But I think it makes sense to support the feature
test macro if *any* of the controlled features are present in glibc.
Tested for x86_64 and x86 (testsuite, and that installed stripped
shared libraries are unchanged by the patch).
* bits/libc-header-start.h: New file.
* Makefile (headers): Add bits/libc-header-start.h.
* include/features.h (__STDC_WANT_LIB_EXT2__): Document.
(__GLIBC_USE): New macro.
* libio/stdio.h: Define
__GLIBC_INTERNAL_STARTING_HEADER_IMPLEMENTATION and include
<bits/libc-header-start.h> instead of including <features.h>.
(fmemopen): Declare also if [__GLIBC_USE (LIB_EXT2)].
(open_memstream): Likewise.
(vasprintf): Declare if [__GLIBC_USE (LIB_EXT2)], not [__USE_GNU].
(__asprintf): Likewise.
(asprintf): Likewise.
(__getdelim): Declare also if [__GLIBC_USE (LIB_EXT2)].
(getdelim): Likewise.
(getline): Likewise.
* string/string.h: Define
__GLIBC_INTERNAL_STARTING_HEADER_IMPLEMENTATION and include
<bits/libc-header-start.h> instead of including <features.h>.
(strdup): Declare also if [__GLIBC_USE (LIB_EXT2)]
(strndup): Likewise.
* wcsmbs/wchar.h: Define
__GLIBC_INTERNAL_STARTING_HEADER_IMPLEMENTATION and include
<bits/libc-header-start.h> instead of including <features.h>.
(open_wmemstream): Declare also if [__GLIBC_USE (LIB_EXT2)].
* manual/creature.texi (__STDC_WANT_LIB_EXT2__): Document macro.
This reverts commit 62ce266b0b.
The change is not mature enough because it needs the following fixes:
1. Redirect test output to a file like other tests
2. Eliminate the need to use a .gdbinit because distributions will
break without it. I should have caught that but I was in too much
of a hurry to get the patch in :/
3. Feature checking during configure to determine things like minimum
required gdb version, python-pexpect version, etc. to make sure
that tests work correctly.
This patch adds pretty printers for the following NPTL types:
- pthread_mutex_t
- pthread_mutexattr_t
- pthread_cond_t
- pthread_condattr_t
- pthread_rwlock_t
- pthread_rwlockattr_t
To load the pretty printers into your gdb session, do the following:
python
import sys
sys.path.insert(0, '/path/to/glibc/build/nptl/pretty-printers')
end
source /path/to/glibc/source/pretty-printers/nptl-printers.py
You can check which printers are registered and enabled by issuing the
'info pretty-printer' gdb command. Printers should trigger automatically when
trying to print a variable of one of the types mentioned above.
The printers are architecture-independent, and were manually tested on both
the gdb CLI and Eclipse CDT.
In order to work, the printers need to know the values of various flags that
are scattered throughout pthread.h and pthreadP.h as enums and #defines. Since
replicating these constants in the printers file itself would create a
maintenance burden, I wrote a script called gen-py-const.awk that Makerules uses
to extract the constants. This script is pretty much the same as gen-as-const.awk,
except it doesn't cast the constant values to 'long' and is thorougly documented.
The constants need only to be enumerated in a .pysym file, which is then referenced
by a Make variable called gen-py-const-headers.
As for the install directory, I discussed this with Mike Frysinger and Siddhesh
Poyarekar, and we agreed that it can be handled in a separate patch, and it shouldn't
block merging of this one.
In addition, I've written a series of test cases for the pretty printers.
Each lock type (mutex, condvar and rwlock) has two test programs, one for itself
and other for its related 'attributes' object. Each test program in turn has a
PExpect-based Python script that drives gdb and compares its output to the
expected printer's. The tests run on the glibc host, which is assumed to have
both gdb and PExpect; if either is absent the tests will fail with code 77
(UNSUPPORTED). For cross-testing you should use cross-test-ssh.sh as test-wrapper.
I've tested the printers on both a native build and a cross build using a Beaglebone
Black, with the build system's filesystem shared with the board through NFS.
Finally, I've written a README that explains all this and more.
Hopefully this should be good to go in now. Thanks.
ChangeLog:
2016-07-04 Martin Galvan <martin.galvan@tallertechnologies.com>
* Makeconfig (build-hardcoded-path-in-tests): Set to 'yes' for shared builds
if tests-need-hardcoded-path is defined.
(all-subdirs): Add pretty-printers.
* Makerules ($(py-const)): New rule.
* Rules (others): Add $(py-const), if defined.
* nptl/Makefile (gen-py-const-headers): Define.
* nptl/nptl-printers.py: New file.
* nptl/nptl_lock_constants.pysym: Likewise.
* pretty-printers/Makefile: Likewise.
* pretty-printers/README: Likewise.
* pretty-printers/test-condvar-attributes.c: Likewise.
* pretty-printers/test-condvar-attributes.p: Likewise.
* pretty-printers/test-condvar-printer.c: Likewise.
* pretty-printers/test-condvar-printer.py: Likewise.
* pretty-printers/test-mutex-attributes.c: Likewise.
* pretty-printers/test-mutex-attributes.py: Likewise.
* pretty-printers/test-mutex-printer.c: Likewise.
* pretty-printers/test-mutex-printer.py: Likewise.
* pretty-printers/test-rwlock-attributes.c: Likewise.
* pretty-printers/test-rwlock-attributes.py: Likewise.
* pretty-printers/test-rwlock-printer.c: Likewise.
* pretty-printers/test-rwlock-printer.py: Likewise.
* pretty-printers/test_common.py: Likewise.
* scripts/gen-py-const.awk: Likewise.
TS 18661 adds nextup and nextdown functions alongside nextafter to provide
support for float128 equivalent to it. This patch adds nextupl, nextup,
nextupf, nextdownl, nextdown and nextdownf to libm before float128 support.
The nextup functions return the next representable value in the direction of
positive infinity and the nextdown functions return the next representable
value in the direction of negative infinity. These are currently enabled
as GNU extensions.
__malloc_initialize_hook is interposed by application code, so
the usual approach to define a compatibility symbol does not work.
This commit adds a new mechanism based on #pragma GCC poison in
<stdc-predef.h>.
The call is technically in a loop, and under certain circumstances
(which are quite difficult to reproduce in a test case), alloca
can be invoked repeatedly during a single call to clntudp_call.
As a result, the available stack space can be exhausted (even
though individual alloca sizes are bounded implicitly by what
can fit into a UDP packet, as a side effect of the earlier
successful send operation).
Instead, we store the data we need from the return value of
readdir in an object of the new type struct readdir_result.
This type is independent of the layout of struct dirent.
https://sourceware.org/glibc/wiki/Proposals/GroupMerging
== Justification ==
It is common today for users to rely on centrally-managed user stores for
handling their user accounts. However, much software existing today does
not have an innate understanding of such accounts. Instead, they commonly
rely on membership in known groups for managing access-control (for
example the "wheel" group on Fedora and RHEL systems or the "adm" group
on Debian-derived systems). In the present incarnation of nsswitch, the
only way to have such groups managed by a remote user store such as
FreeIPA or Active Directory would be to manually remove the groups from
/etc/group on the clients so that nsswitch would then move past nss_files
and into the SSSD, nss-ldap or other remote user database.
== Solution ==
With this patch, a new action is introduced for nsswitch:
NSS_ACTION_MERGE. To take advantage of it, one will add [SUCCESS=merge]
between two database entries in the nsswitch.conf file. When a group is
located in the first of the two group entries, processing will continue
on to the next one. If the group is also found in the next entry (and the
group name and GID are an exact match), the member list of the second
entry will be added to the group object to be returned.
== Implementation ==
After each DL_LOOKUP_FN() returns, the next action is checked. If the
function returned NSS_STATUS_SUCCESS and the next action is
NSS_ACTION_MERGE, a copy of the result buffer is saved for the next pass
through the loop. If on this next pass through the loop the database
returns another instance of a group matching both the group name and GID,
the member list is added to the previous list and it is returned as a
single object. If the following database does not contain the same group,
then the original is copied back into the destination buffer.
This patch implements merge functionality only for the group database.
For other databases, there is a default implementation that will return
the EINVAL errno if a merge is requested. The merge functionality can be
implemented for other databases at a later time if such is needed. Each
database must provide a unique implementation of the deep-copy and merge
functions.
If [SUCCESS=merge] is present in nsswitch.conf for a glibc version that
does not support it, glibc will process results up until that operation,
at which time it will return results if it has found them or else will
simply return an error. In practical terms, this ends up behaving like
the remainder of the nsswitch.conf line does not exist.
== Iterators ==
This feature does not modify the iterator functionality from its current
behavior. If getgrnam() or getgrgid() is called, glibc will iterate
through all entries in the `group` line in nsswitch.conf and display the
list of members without attempting to merge them. This is consistent with
the behavior of nss_files where if two separate lines are specified for
the same group in /etc/groups, getgrnam()/getgrgid() will display both.
Clients are already expected to handle this gracefully.
== No Premature Optimizations ==
The following is a list of places that might be eligible for
optimization, but were not overengineered for this initial contribution:
* Any situation where a merge may occur will result in one malloc() of
the same size as the input buffer.
* Any situation where a merge does occur will result in a second
malloc() to hold the list of pointers to member name strings.
* The list of members is simply concatenated together and is not tested
for uniqueness (which is identical to the behavior for nss_files,
which will simply return identical values if they both exist on the
line in the file. This could potentially be optimized to reduce space
usage in the buffer, but it is both complex and computationally
expensive to do so.
== Testing ==
I performed testing by running the getent utility against my newly-built
glibc and configuring /etc/nsswitch.conf with the following entry:
group: group: files [SUCCESS=merge] sss
In /etc/group I included the line:
wheel❌10:sgallagh
I then configured my local SSSD using the id_provider=local to respond
with:
wheel:*:10:localuser,localuser2
I then ran `getent group wheel` against the newly-built glibc in
multiple situations and received the expected output as described
above:
* When SSSD was running.
* When SSSD was configured in nsswitch.conf but the daemon was not
running.
* When SSSD was configured in nsswitch.conf but nss_sss.so.2 was not
installed on the system.
* When the order of 'sss' and 'files' was reversed.
* All of the above with the [SUCCESS=merge] removed (to ensure no
regressions).
* All of the above with `getent group 10`.
* All of the above with `getent group` with and without
`enumerate=true` set in SSSD.
* All of the above with and without nscd enabled on the system.
When converting a struct hostent response to struct gaih_addrtuple, the
gethosts macro (which is called from gaih_inet) used alloca, without
malloc fallback for large responses. This commit changes this code to
use calloc unconditionally.
This commit also consolidated a second hostent-to-gaih_addrtuple
conversion loop (in gaih_inet) to use the new conversion function.
The overloading approach in the W* macros was incompatible with
integer expressions of a type different from int. Applications
using union wait and these macros will have to migrate to the
POSIX-specified int status type.
In <https://sourceware.org/ml/libc-alpha/2016-01/msg00885.html> I
proposed a minimum Linux kernel version of 3.2 for glibc 2.24, since
Linux 2.6.32 has reached EOL.
In the discussion in February, some concerns were expressed about
compatibility with OpenVZ containers. It's not clear that these are
real issues, given OpenVZ backporting kernel features and faking the
kernel version for guest software, as discussed in
<https://sourceware.org/ml/libc-alpha/2016-02/msg00278.html>. It's
also not clear that supporting running GNU/Linux distributions from
late 2016 (at the earliest) on a kernel series from 2009 is a sensible
expectation. However, as an interim step, this patch increases the
requirement everywhere except x86 / x86_64 (since the controversy was
only about those architectures); the special caveats and settings can
easily be removed later when we're ready to increase the requirements
on x86 / x86_64 (and if someone would like to raise the issue on LWN
as suggested in the previous discussion, that would be welcome). 3.2
kernel headers are required everywhere by this patch.
(x32 already requires 3.4 or later, so is unaffected by this patch.)
As usual for such a change, this patch only changes the configure
scripts and associated documentation. The intent is to follow up with
removal of dead __LINUX_KERNEL_VERSION conditionals. Each __ASSUME_*
or other macro that becomes dead can then be removed independently.
Tested for x86_64 and x86.
* sysdeps/unix/sysv/linux/configure.ac (LIBC_LINUX_VERSION):
Define to 3.2.0.
(arch_minimum_kernel): Likewise.
* sysdeps/unix/sysv/linux/configure: Regenerated.
* sysdeps/unix/sysv/linux/i386/configure.ac (arch_minimum_kernel):
Define to 2.6.32.
* sysdeps/unix/sysv/linux/i386/configure: Regenerated.
* sysdeps/unix/sysv/linux/x86_64/64/configure.ac
(arch_minimum_kernel): Define to 2.6.32.
* sysdeps/unix/sysv/linux/x86_64/64/configure: Regenerated.
* README: Document Linux 3.2 requirement.
* manual/install.texi (Linux): Document Linux 3.2 headers
requirement.
* INSTALL: Regenerated.
From the bug:
Netherlands Antilles was dissolved, and "AN" is not a part of ISO 3166
anymore. According to setlocale(3), "territory is an ISO 3166 country
code". We now have pap_AW and pap_CW.
Reported-by: Chris Leonard <cjlhomeaddress@gmail.com>
* A stack-based buffer overflow was found in libresolv when invoked from
libnss_dns, allowing specially crafted DNS responses to seize control
of execution flow in the DNS client. The buffer overflow occurs in
the functions send_dg (send datagram) and send_vc (send TCP) for the
NSS module libnss_dns.so.2 when calling getaddrinfo with AF_UNSPEC
family. The use of AF_UNSPEC triggers the low-level resolver code to
send out two parallel queries for A and AAAA. A mismanagement of the
buffers used for those queries could result in the response of a query
writing beyond the alloca allocated buffer created by
_nss_dns_gethostbyname4_r. Buffer management is simplified to remove
the overflow. Thanks to the Google Security Team and Red Hat for
reporting the security impact of this issue, and Robert Holiday of
Ciena for reporting the related bug 18665. (CVE-2015-7547)
See also:
https://sourceware.org/ml/libc-alpha/2016-02/msg00416.htmlhttps://sourceware.org/ml/libc-alpha/2016-02/msg00418.html
Various Linux kernel syscalls have become obsolete over time.
Specifically, the following are obsolete in all kernel versions
supported by glibc, are not present for architectures more recently
added to the kernel, and as such, the wrapper functions for them
should be compat symbols, not in static libc and not available for new
links with shared libc.
* bdflush: in Linux 2.6, does nothing if present.
* create_module get_kernel_syms query_module: Linux 2.4 module
interface, syscalls not present in Linux 2.6.
* uselib: part of the mechanism for loading a.out shared libraries,
irrelevant with ELF.
This patch adds support for syscalls.list to list syscall aliases of
the form NAME@VERSION:OBSOLETED, with SHLIB_COMPAT conditionals being
generated for such aliases. Those five syscalls are then made into
compat symbols (obsoleted in glibc 2.23, so future ports won't have
these symbols at all), with the header <sys/kdaemon.h> declaring
bdflush being removed. When we move to 3.2 as minimum kernel version,
the same can be done for nfsservctl (removed in Linux 3.1) as well.
Tested for x86_64 and x86 (testsuite, as well as checking that the
symbols in question indeed become compat symbols, that they are indeed
omitted from static libc, and that the generated SHLIB_COMPAT
conditionals look right).
[BZ #18472]
* sysdeps/unix/Makefile ($(objpfx)stub-syscalls.c): Handle entries
for the form NAME@VERSION:OBSOLETED and generate SHLIB_COMPAT
conditionals for them.
* sysdeps/unix/make-syscalls.sh (emit_weak_aliases): Likewise.
* sysdeps/unix/sysv/linux/sys/kdaemon.h: Remove file.
* sysdeps/unix/sysv/linux/Makefile (sysdep_headers): Remove
sys/kdaemon.h.
* sysdeps/unix/sysv/linux/syscalls.list (bdflush): Make into
compat-only syscall, obsoleted in glibc 2.23.
(create_module): Likewise.
(get_kernel_syms): Likewise.
(query_module): Likewise.
(uselib): Likewise.
* manual/sysinfo.texi (System Parameters): Do not mention bdflush.
Update __STDC_ISO_10646__ to 201505L for Unicode 8.0.0.
Update character encoding, ctype, and transliteration tables.
New scripts autogenerate transliteration tables.
The nan, nanf and nanl functions handle payload strings by doing e.g.:
if (tagp[0] != '\0')
{
char buf[6 + strlen (tagp)];
sprintf (buf, "NAN(%s)", tagp);
return strtod (buf, NULL);
}
This is an unbounded stack allocation based on the length of the
argument. Furthermore, if the argument starts with an n-char-sequence
followed by ')', that n-char-sequence is wrongly treated as
significant for determining the payload of the resulting NaN, when ISO
C says the call should be equivalent to strtod ("NAN", NULL), without
being affected by that initial n-char-sequence. This patch fixes both
those problems by using the __strtod_nan etc. functions recently
factored out of strtod etc. for that purpose, with those functions
being exported from libc at version GLIBC_PRIVATE.
Tested for x86_64, x86, mips64 and powerpc.
[BZ #16961]
[BZ #16962]
* math/s_nan.c (__nan): Use __strtod_nan instead of constructing a
string on the stack for strtod.
* math/s_nanf.c (__nanf): Use __strtof_nan instead of constructing
a string on the stack for strtof.
* math/s_nanl.c (__nanl): Use __strtold_nan instead of
constructing a string on the stack for strtold.
* stdlib/Versions (libc): Add __strtof_nan, __strtod_nan and
__strtold_nan to GLIBC_PRIVATE.
* math/test-nan-overflow.c: New file.
* math/test-nan-payload.c: Likewise.
* math/Makefile (tests): Add test-nan-overflow and
test-nan-payload.
With current kernel versions, the check does not reliably detect that
unavailable CPUs are requested, for these reasons:
(1) The kernel will silently ignore non-allowed CPUs, that is, CPUs
which are physically present but disallowed for the thread
based on system configuration.
(2) Similarly, CPU bits which lack an online CPU (possible CPUs)
are ignored.
(3) The existing probing code assumes that the CPU mask size is a
power of two and at least 1024. Neither has it to be a power
of two, nor is the minimum possible value 1024, so the value
determined is often too large. This means that the CPU set
size check in glibc accepts CPU bits beyond the actual hard
system limit.
(4) Future kernel versions may not even have a fixed CPU set size.
After the removal of the probing code, the kernel still returns
EINVAL if no CPU in the requested set remains which can run the
thread after the affinity change.
Applications which care about the exact affinity mask will have
to query it using sched_getaffinity after setting it. Due to the
effects described above, this commit does not change this.
The new tests supersede tst-getcpu, which is removed. This
addresses bug 19164 because the new tests allocate CPU sets
dynamically.
* nptl/check-cpuset.h: Remove.
* nptl/pthread_attr_setaffinity.c (__pthread_attr_setaffinity_new):
Remove CPU set size check.
* nptl/pthread_setattr_default_np.c (pthread_setattr_default_np):
Likewise.
* sysdeps/unix/sysv/linux/check-cpuset.h: Remove.
* sysdeps/unix/sysv/linux/pthread_setaffinity.c
(__kernel_cpumask_size, __determine_cpumask_size): Remove.
(__pthread_setaffinity_new): Remove CPU set size check.
* sysdeps/unix/sysv/linux/sched_setaffinity.c
(__kernel_cpumask_size): Remove.
(__sched_setaffinity_new): Remove CPU set size check.
* manual/threads.texi (Default Thread Attributes): Remove stale
reference to check_cpuset_attr, determine_cpumask_size in comment.
* sysdeps/unix/sysv/linux/Makefile [$(subdir) == posix] (tests):
Remove tst-getcpu. Add tst-affinity, tst-affinity-pid.
[$(subdir) == nptl] (tests): Add tst-thread-affinity-pthread,
tst-thread-affinity-pthread2, tst-thread-affinity-sched.
* sysdeps/unix/sysv/linux/tst-affinity.c: New file.
* sysdeps/unix/sysv/linux/tst-affinity-pid.c: New file.
* sysdeps/unix/sysv/linux/tst-skeleton-affinity.c: New skeleton test file.
* sysdeps/unix/sysv/linux/tst-thread-affinity-sched.c: New file.
* sysdeps/unix/sysv/linux/tst-thread-affinity-pthread.c: New file.
* sysdeps/unix/sysv/linux/tst-thread-affinity-pthread2.c: New file.
* sysdeps/unix/sysv/linux/tst-thread-skeleton-affinity.c: New
skeleton test file.
* sysdeps/unix/sysv/linux/tst-getcpu.c: Remove. Superseded by
tst-affinity-pid.
The lgamma (and likewise lgammaf, lgammal) function wrongly sets the
signgam variable even when building for strict ISO C conformance
(-std=c99 / -std=c11), although the user may define such a variable
and it's only in the implementation namespace for POSIX with XSI
extensions enabled.
Following discussions starting at
<https://sourceware.org/ml/libc-alpha/2013-04/msg00767.html> and
<https://sourceware.org/ml/libc-alpha/2015-10/msg00844.html>, it seems
that the safest approach for fixing this particular issue is for
signgam to become a weak alias for a newly exported symbol __signgam,
with the library functions only setting __signgam, at which point
static linker magic will preserve the alias for newly linked binaries
that refer to the library's signgam rather than defining their own,
while breaking the alias for programs that define their own signgam,
with new symbol versions for lgamma functions and with compat symbols
for existing binaries that set both signgam and __signgam.
This patch implements that approach for the fix. signgam is made into
a weak alias. The four symbols __signgam, lgamma, lgammaf, lgammal
get new symbol versions at version GLIBC_2.23, with the existing
versions of lgamma, lgammaf and lgammal becoming compat symbols.
When the compat versions are built, gamma, gammaf and gammal are
aliases for the compat versions (i.e. always set signgam); this is OK
as they are not ISO C functions, and avoids adding new symbol versions
for them unnecessarily. When the compat versions are not built
(i.e. for static linking and for future glibc ports), gamma, gammaf
and gammal are aliases for the new versions that set __signgam. The
ldbl-opt versions are updated accordingly.
The lgamma wrappers are adjusted so that the same source files,
included from different files with different definitions of
USE_AS_COMPAT, can build either the new versions or the compat
versions. Similar changes are made to the ia64 versions (untested).
Tests are added that the lgamma functions do not interfere with a user
variable called signgam for ISO C, with various choices for the size
of that variable, whether it is initialized, and for static and
dynamic linking. The conformtest whitelist entry is removed as well.
Tested for x86_64, x86, mips64 and powerpc, including looking at
objdump --dynamic-syms output to make sure the expected sets of
symbols were aliases. Also spot-tested that a binary built with old
glibc works properly (i.e. gets signgam set) when run with new glibc.
[BZ #15421]
* sysdeps/ieee754/s_signgam.c (signgam): Rename to __signgam,
initialize with 0 and define as weak alias of __signgam.
* include/math.h [!_ISOMAC] (__signgam): Declare.
* math/Makefile (libm-calls): Add w_lgamma_compat.
(tests): Add test-signgam-uchar, test-signgam-uchar-init,
test-signgam-uint, test-signgam-uint-init, test-signgam-ullong and
test-signgam-ullong-init.
(tests-static): Add test-signgam-uchar-static,
test-signgam-uchar-init-static, test-signgam-uint-static,
test-signgam-uint-init-static, test-signgam-ullong-static and
test-signgam-ullong-init-static.
(CFLAGS-test-signgam-uchar.c): New variable.
(CFLAGS-test-signgam-uchar-init.c): Likewise.
(CFLAGS-test-signgam-uchar-static.c): Likewise.
(CFLAGS-test-signgam-uchar-init-static.c): Likewise.
(CFLAGS-test-signgam-uint.c): Likewise.
(CFLAGS-test-signgam-uint-init.c): Likewise.
(CFLAGS-test-signgam-uint-static.c): Likewise.
(CFLAGS-test-signgam-uint-init-static.c): Likewise.
(CFLAGS-test-signgam-ullong.c): Likewise.
(CFLAGS-test-signgam-ullong-init.c): Likewise.
(CFLAGS-test-signgam-ullong-static.c): Likewise.
(CFLAGS-test-signgam-ullong-init-static.c): Likewise.
* math/Versions (libm): Add GLIBC_2.23.
* math/lgamma-compat.h: New file.
* math/test-signgam-main.c: Likewise.
* math/test-signgam-uchar-init-static.c: Likewise.
* math/test-signgam-uchar-init.c: Likewise.
* math/test-signgam-uchar-static.c: Likewise.
* math/test-signgam-uchar.c: Likewise.
* math/test-signgam-uint-init-static.c: Likewise.
* math/test-signgam-uint-init.c: Likewise.
* math/test-signgam-uint-static.c: Likewise.
* math/test-signgam-uint.c: Likewise.
* math/test-signgam-ullong-init-static.c: Likewise.
* math/test-signgam-ullong-init.c: Likewise.
* math/test-signgam-ullong-static.c: Likewise.
* math/test-signgam-ullong.c: Likewise.
* math/w_lgamma.c: Rename to w_lgamma_main.c and replace by
wrapper of w_lgamma_main.c.
* math/w_lgamma_compat.c: New file.
* math/w_lgamma_compatf.c: Likewise.
* math/w_lgamma_compatl.c: Likewise.
* math/w_lgamma_main.c: New file. Based on w_lgamma.c. Include
<lgamma-compat.h>. Condition contents on [BUILD_LGAMMA]. Support
defining compatibility symbols.
(__lgamma): Change to LGFUNC (__lgamma). Use CALL_LGAMMA.
* math/w_lgammaf.c: Rename to w_lgammaf_main.c and replace by
wrapper of w_lgammaf_main.c.
* math/w_lgammaf_main.c: New file. Based on w_lgammaf.c. Include
<lgamma-compat.h>. Condition contents on [BUILD_LGAMMA]. Support
defining compatibility symbols.
(__lgammaf): Change to LGFUNC (__lgammaf). Use CALL_LGAMMA.
* math/w_lgammal.c: Rename to w_lgammal_main.c and replace by
wrapper of w_lgammal_main.c.
* math/w_lgammal_main.c: New file. Based on w_lgammal.c. Include
<lgamma-compat.h>. Condition contents on [BUILD_LGAMMA]. Support
defining compatibility symbols.
(__lgammal): Change to LGFUNC (__lgammal). Use CALL_LGAMMA.
* sysdeps/ia64/fpu/lgamma-compat.h: New file.
* sysdeps/ia64/fpu/w_lgamma.c: Move to ....
* sysdeps/ia64/fpu/w_lgamma_main.c: ...here. Include
<lgamma-compat.h>.
(__ieee754_lgamma): Change to LGFUNC (lgamma). Use CALL_LGAMMA.
(__ieee754_gamma): Define as alias.
* sysdeps/ia64/fpu/w_lgammaf.c: Move to ....
* sysdeps/ia64/fpu/w_lgammaf_main.c: ...here. Include
<lgamma-compat.h>.
(__ieee754_lgammaf): Change to LGFUNC (lgammaf). Use CALL_LGAMMA.
(__ieee754_gammaf): Define as alias.
* sysdeps/ia64/fpu/w_lgammal.c: Move to ....
* sysdeps/ia64/fpu/w_lgammal_main.c: ...here. Include
<lgamma-compat.h>.
(__ieee754_lgammal): Change to LGFUNC (lgammal). Use CALL_LGAMMA.
(__ieee754_gammal): Define as alias.
* sysdeps/ieee754/ldbl-opt/w_lgamma.c: Move to ....
* sysdeps/ieee754/ldbl-opt/w_lgamma_compat.c: ...here. Include
<math/w_lgamma_compat.c>.
[LONG_DOUBLE_COMPAT(libm, GLIBC_2_0)] (__lgammal_dbl_compat):
Define as alias of __lgamma_compat and use in defining lgammal.
* sysdeps/ieee754/ldbl-opt/w_lgammal.c: Move to ....
* sysdeps/ieee754/ldbl-opt/w_lgamma_compatl.c: ...here. Include
<math/lgamma-compat.h> and <math/w_lgamma_compatl.c>.
(USE_AS_COMPAT): New macro.
(LGAMMA_OLD_VER): Undefine and redefine.
(lgammal): Do not define here.
(gammal): Only define here if [GAMMA_ALIAS].
* conform/linknamespace.pl (@whitelist): Remove signgam.
* sysdeps/nacl/libm.abilist: Update.
* sysdeps/unix/sysv/linux/aarch64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/alpha/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/arm/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/hppa/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/i386/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/ia64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/m68k/coldfire/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/m68k/m680x0/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/microblaze/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/nios2/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libm.abilist:
Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libm.abilist:
Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/libm-le.abilist:
Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/libm.abilist:
Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/sh/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc32/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/tile/tilegx/tilegx32/libm.abilist:
Likewise.
* sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/libm.abilist:
Likewise.
* sysdeps/unix/sysv/linux/tile/tilepro/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/x86_64/64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/x86_64/x32/libm.abilist: Likewise.
The recvmsg system calls for netlink sockets have been particularly
prone to picking up unrelated data after a file descriptor race
(where the descriptor is closed and reopened concurrently in a
multi-threaded process, as the result of a file descriptor
management issue elsewhere). This commit adds additional error
checking and aborts the process if a datagram of unexpected length
(without the netlink header) is received, or an error code which
cannot happen due to the way the netlink socket is used.
[BZ #12926]
Terminate process on invalid netlink response.
* sysdeps/unix/sysv/linux/netlinkaccess.h
(__netlink_assert_response): Declare.
* sysdeps/unix/sysv/linux/netlink_assert_response.c: New file.
* sysdeps/unix/sysv/linux/Makefile [$(subdir) == inet]
(sysdep_routines): Add netlink_assert_response.
* sysdeps/unix/sysv/linux/check_native.c (__check_native): Call
__netlink_assert_response.
* sysdeps/unix/sysv/linux/check_pf.c (make_request): Likewise.
* sysdeps/unix/sysv/linux/ifaddrs.c (__netlink_request): Likewise.
* sysdeps/unix/sysv/linux/Versions (GLIBC_PRIVATE): Add
__netlink_assert_response.
For the -ffinite-math-only versions of various x86_64 and x86 log*
functions, a zero result from log* (1) is returned with incorrect sign
in round-downward mode. This patch fixes this in a similar way to the
previous fixes for the non-*_finite versions of the functions.
Tested for x86_64 and x86 (including an i586 build), together with a
patch that will be applied separately to enable the main libm-test.inc
tests for the finite-math-only functions.
[BZ #19213]
* sysdeps/i386/fpu/e_log.S (__log_finite): Ensure +0 is always
returned for argument 1.
* sysdeps/i386/fpu/e_logf.S (__logf_finite): Likewise.
* sysdeps/i386/fpu/e_logl.S (__logl_finite): Likewise.
* sysdeps/i386/i686/fpu/e_logl.S (__logl_finite): Likewise.
* sysdeps/x86_64/fpu/e_log10l.S (__log10l_finite): Likewise.
* sysdeps/x86_64/fpu/e_log2l.S (__log2l_finite): Likewise.
* sysdeps/x86_64/fpu/e_logl.S (__logl_finite): Likewise.
The lgamma inline functions in bits/math-finite.h do not set signgam
if __USE_ISOC99, even when other feature test macros mean a standard
such as XSI POSIX is selected for which it should be set. (This is
essentially the opposite issue to bug 15421, the out-of-line versions
setting signgam even when they shouldn't.)
This patch fixes those functions to use __USE_MISC || __USE_XOPEN as
the condition for when to set signgam, since it's the condition for
when math.h declares signgam. The legacy gamma* names are only
declared at all if __USE_MISC || __USE_XOPEN, so they just set signgam
unconditionally.
Tests for certain standards or not using _GNU_SOURCE cannot use
test-skeleton.c (this is a known issue noted on the wiki todo list).
Thus, the new tests that signgam remains not set in ISO C modes do not
use test-skeleton.c. They also define _ISOMAC to avoid running into
declarations in the internal include/ headers that only work in
_GNU_SOURCE mode.
Tested for x86_64 and x86.
[BZ #19211]
* math/bits/math-finite.h (lgamma): Set signgam if [__USE_MISC ||
__USE_XOPEN], not if [!__USE_ISOC99].
(lgammaf): Likewise.
(lgammal): Likewise.
(gamma): Set signgam unconditionally, not if [!__USE_ISOC99].
(gammaf): Likewise.
(gammal): Likewise.
* math/test-signgam-finite-c11.c: New file.
* math/test-signgam-finite-c99.c: Likewise.
* math/test-signgam-finite.c: Likewise.
* math/Makefile (tests): Add test-signgam-finite,
test-signgam-finite-c99 and test-signgam-finite-c11.
(CFLAGS-test-signgam-finite.c): New variable.
(CFLAGS-test-signgam-finite-c99.c): Likewise.
(CFLAGS-test-signgam-finite-c11.c): Likewise.
features.h is not clean with -Wundef (for the installed header, of
course this only appears with -Wsystem-headers). In ISO C standards
modes, you get a series of warnings / errors relating to
_POSIX_C_SOURCE and _XOPEN_SOURCE not being defined when tested in
standards mode and uses #undef _GNU_SOURCE to avoid the default
_GNU_SOURCE from libc-symbols.h. This patch changes the relevant #if
conditionals to avoid these warnings / errors.
Tested for x86_64 and x86 (testsuite, and that installed shared
libraries are unchanged by the patch).
[BZ #19212]
* include/features.h [(_XOPEN_SOURCE - 0) >= 500]: Change
conditional to [defined _XOPEN_SOURCE && (_XOPEN_SOURCE - 0) >=
500].
[_POSIX_C_SOURCE >= 1]: Change conditional to [defined
_POSIX_C_SOURCE && _POSIX_C_SOURCE >= 1].
[(_POSIX_C_SOURCE - 0) >= 199309L]: Change conditional to [defined
_POSIX_C_SOURCE && (_POSIX_C_SOURCE - 0) >= 199309L].
[(_POSIX_C_SOURCE - 0) >= 199506L]: Change conditional to [defined
_POSIX_C_SOURCE && (_POSIX_C_SOURCE - 0) >= 199506L].
[(_POSIX_C_SOURCE - 0) >= 200112L]: Change conditional to [defined
_POSIX_C_SOURCE && (_POSIX_C_SOURCE - 0) >= 200112L].
[(_POSIX_C_SOURCE - 0) >= 200809L]: Change conditional to [defined
_POSIX_C_SOURCE && (_POSIX_C_SOURCE - 0) >= 200809L].
bits/math-finite.h maps ldexp functions to corresponding scalbn
functions. This is (a) a namespace bug for C90, which has ldexp but
not scalbn, and (b) in any case useless, since the ldexp and scalbn
functions have identical semantics (for floating-point types with
radix 2), and since the fix for bug 6803 are actually aliases
(presumably the mapping was based around the old bug of scalbn not
setting errno). This patch removes the bogus redirections.
Tested for x86_64 and x86.
[BZ #19209]
* math/bits/math-finite.h (ldexp): Remove declaration.
(ldexpf): Likewise.
(ldexpl): Likewise.
bits/math-finite.h declares -ffinite-math-only variants of various
functions under conditions not matching those under which the normal
versions are declared.
* math.h only ever includes bits/mathcalls.h to declare float and long
double functions if __USE_ISOC99, but bits/math-finite.h declares
some float functions regardless (long double ones are conditioned on
__MATH_DECLARE_LDOUBLE). (For C90 functions this isn't a
conformance bug because C90 reserves the float and long double
names, but is still contrary to good glibc practice. For some other
functions in older XSI standards it *is* a conformance bug.)
* Some functions are defined as inlines using lgamma_r functions under
conditions where those lgamma_r functions are not themselves
declared.
* hypot is declared under __USE_XOPEN || __USE_ISOC99 in
bits/mathcalls.h, __USE_ISOC99 only in bits/math-finite.h.
* float and long double versions of Bessel functions should be limited
to __USE_MISC (as in bug 18977).
* gamma should not be declared for __USE_XOPEN2K (as in bug 18967).
* remainder should be restricted to __USE_XOPEN_EXTENDED ||
__USE_ISOC99, not unconditional.
* scalb should not be declared for __USE_XOPEN2K8, and scalbf and
scalbl are non-POSIX (as in bug 18967).
This patch fixes all these issues (it doesn't seem worth splitting
them into separate patches or bugs). I put __USE_ISOC99 conditionals,
where needed, around both float and long double declarations, even
though formally redundant around the long double declarations because
__MATH_DECLARE_LDOUBLE isn't defined without __USE_ISOC99; it seemed
clearer that way. The missing declarations of lgamma_r functions are
dealt with by directly using declarations of __lgamma*_r_finite, in
the implementation namespace, rather than having the inlines rely on
asm redirection of lgamma*_r.
After this patch, there are some apparently redundant nested
__USE_ISOC99 conditionals in lgamma / gamma definitions. These
actually reflect a separate bug (the correct condition for the lgamma
inline functions to set signgam is __USE_MISC || __USE_XOPEN, the
condition under which signgam is declared, rather than disabling
setting it if __USE_ISOC99, which includes XSI POSIX versions for
which signgam *should* be set). They'll be fixed as part of a fix for
that bug, which will also add tests for these inlines. I've put a
note about more general conform/ test coverage for -ffinite-math-only
on
<https://sourceware.org/glibc/wiki/Development_Todo/Master#conformtest_improvements>,
alongside other options for which this is also relevant (some of which
have also had such bugs in the past relating to mismatched
conditionals).
I also intend to enable the main libm-test.inc tests for the
math-finite.h functions, but some other bugs in __*_finite need fixing
first.
[BZ #19205]
* math/bits/math-finite.h (acosf): Condition declaration on
[__USE_ISOC99].
(acosl): Likewise.
(acoshf): Likewise.
(acoshl): Likewise.
(asinf): Likewise.
(asinl): Likewise.
(atan2f): Likewise.
(atan2l): Likewise.
(atanhf): Likewise.
(atanhl): Likewise.
(coshf): Likewise.
(coshl): Likewise.
(expf): Likewise.
(expl): Likewise.
(fmodf): Likewise.
(fmodl): Likewise.
(hypot): Change condition to [__USE_XOPEN || __USE_ISOC99].
(j0f): Change condition to [__USE_MISC && __USE_ISOC99].
(j0l): Likewise.
(y0f): Likewise.
(y0l): Likewise.
(j1f): Likewise.
(j1l): Likewise.
(y1f): Likewise.
(y1l): Likewise.
(jnf): Likewise.
(jnl): Likewise.
(ynf): Likewise.
(ynl): Likewise.
(lgammaf_r): Condition declaration on [__USE_ISOC99].
(lgammal_r): Likewise.
(__lgamma_r_finite): New declaration.
(__lgammaf_r_finite): Likewise.
(__lgammal_r_finite): Likewise.
(lgamma): Use __lgamma_r_finite.
(lgammaf): Condition definition on [__USE_ISOC99]. Use
__lgammaf_r_finite.
(lgammal): Condition definition on [__USE_ISOC99]. Use
__lgammal_r_finite.
(gamma): Do not define for [!__USE_MISC && __USE_XOPEN2K]. Use
__lgamma_r_finite.
(gammaf): Condition definition on [__USE_ISOC99]. Use
__lgammaf_r_finite.
(gammal): Condition definition on [__USE_ISOC99]. Use
__lgammal_r_finite.
(logf): Condition declaration on [__USE_ISOC99].
(logl): Likewise.
(log10f): Likewise.
(log10l): Likewise.
(ldexpf): Likewise.
(ldexpl): Likewise.
(powf): Likewise.
(powl): Likewise.
(remainder): Condition declaration on [__USE_XOPEN_EXTENDED ||
__USE_ISOC99].
(remainderf): Condition declaration on [__USE_ISOC99].
(remainderl): Likewise.
(scalb): Do not declare for [!__USE_MISC && __USE_XOPEN2K8].
(scalbf): Change condition to [__USE_MISC && __USE_ISOC99].
(scalbl): Likewise.
(sinhf): Condition declaration on [__USE_ISOC99].
(sinhl): Likewise.
(sqrtf): Likewise.
(sqrtl): Likewise.
For some large arguments, the dbl-64 implementation of remainder gives
zero results with the wrong sign, resulting from a subtraction that is
mathematically correct but does not guarantee that a zero result has
the sign of the first argument to remainder. This patch adds an
appropriate check for this case, similar to other implementations of
remainder in the case of equality, and adds tests of remainder on
inputs already used to test remquo.
Tested for x86_64 and x86.
[BZ #19201]
* sysdeps/ieee754/dbl-64/e_remainder.c (__ieee754_remainder):
Check for zero remainder in case of large exponents and ensure
correct sign of result in that case.
* math/libm-test.inc (remainder_test_data): Add more tests.
nextafter and nexttoward fail to set errno on overflow and underflow.
This patch makes them do so in cases that should include all the cases
where such errno setting is required by glibc's goals for when to set
errno (but not all cases of underflow where the result is nonzero and
so glibc's goals do not require errno setting).
Tested for x86_64, x86, mips64 and powerpc.
[BZ #6799]
* math/s_nextafter.c: Include <errno.h>.
(__nextafter): Set errno on overflow and underflow.
* math/s_nexttowardf.c: Include <errno.h>.
(__nexttowardf): Set errno on overflow and underflow.
* sysdeps/i386/fpu/s_nextafterl.c: Include <errno.h>.
(__nextafterl): Set errno on overflow and underflow.
* sysdeps/i386/fpu/s_nexttoward.c: Include <errno.h>.
(__nexttoward): Set errno on overflow and underflow.
* sysdeps/i386/fpu/s_nexttowardf.c: Include <errno.h>.
(__nexttowardf): Set errno on overflow and underflow.
* sysdeps/ieee754/flt-32/s_nextafterf.c: Include <errno.h>.
(__nextafterf): Set errno on overflow and underflow.
* sysdeps/ieee754/ldbl-128/s_nextafterl.c: Include <errno.h>.
(__nextafterl): Set errno on overflow and underflow.
* sysdeps/ieee754/ldbl-128/s_nexttoward.c: Include <errno.h>.
(__nexttoward): Set errno on overflow and underflow.
* sysdeps/ieee754/ldbl-128/s_nexttowardf.c: Include <errno.h>.
(__nexttowardf): Set errno on overflow and underflow.
* sysdeps/ieee754/ldbl-128ibm/s_nextafterl.c: Include <errno.h>.
(__nextafterl): Set errno on overflow and underflow.
* sysdeps/ieee754/ldbl-128ibm/s_nexttoward.c: Include <errno.h>.
(__nexttoward): Set errno on overflow and underflow.
* sysdeps/ieee754/ldbl-128ibm/s_nexttowardf.c: Include <errno.h>.
(__nexttowardf): Set errno on overflow and underflow.
* sysdeps/ieee754/ldbl-96/s_nexttoward.c: Include <errno.h>.
(__nexttoward): Set errno on overflow and underflow.
* sysdeps/ieee754/ldbl-96/s_nexttowardf.c: Include <errno.h>.
(__nexttowardf): Set errno on overflow and underflow.
* sysdeps/ieee754/ldbl-opt/s_nexttowardfd.c: Include <errno.h>.
(__nldbl_nexttowardf): Set errno on overflow and underflow.
* sysdeps/m68k/m680x0/fpu/s_nextafterl.c: Include <errno.h>.
(__nextafterl): Set errno on overflow and underflow.
* math/libm-test.inc (nextafter_test_data): Do not allow errno
setting to be missing on overflow. Add more tests.
(nexttoward_test_data): Likewise.
The ldbl-128 version of log1pl raises a spurious "invalid" exception
for a -qNaN argument. This patch fixes this by making the initial
check for infinities and NaNs handle arguments of both signs in such a
way that NaNs result in a NaN being returned (quietly if the input NaN
was quiet) while +Inf results in +Inf being returned and -Inf results
in a qNaN being returned with "invalid" exception raised.
Tested for mips64.
[BZ #19189]
* sysdeps/ieee754/ldbl-128/s_log1pl.c (__log1pl): Make check for
non-finite argument handle arguments with negative sign.
The libm drem functions just call the corresponding __remainder
functions. This patch removes the unnecessary wrappers by making them
into weak aliases at the ELF level.
Tested for x86_64, x86, mips64 and powerpc.
[BZ #16171]
* math/w_remainder.c (drem): Define as weak alias of __remainder.
[NO_LONG_DOUBLE] (dreml): Define as weak alias of __remainder.
* math/w_remainderf.c (dremf): Define as weak alias of
__remainderf.
* math/w_remainderl.c (dreml): Define as weak alias of
__remainderl.
* sysdeps/ia64/fpu/e_remainder.S (drem): Define as weak alias of
__remainder.
* sysdeps/ia64/fpu/e_remainderf.S (dremf): Define as weak alias of
__remainderf.
* sysdeps/ia64/fpu/e_remainderl.S (dreml): Define as weak alias of
__remainderl.
* sysdeps/ieee754/ldbl-opt/nldbl-remainder.c (dreml): Define as
weak alias of remainderl.
* sysdeps/ieee754/ldbl-opt/w_remainder.c
[LONG_DOUBLE_COMPAT(libm, GLIBC_2_0)] (__drem): Define as strong
alias of __remainder.
[LONG_DOUBLE_COMPAT(libm, GLIBC_2_0)] (dreml): Use compat_symbol.
* sysdeps/ieee754/ldbl-opt/w_remainderl.c (__dreml): Define as
strong alias of __remainderl.
(dreml): Use long_double_symbol.
* math/Makefile (libm-calls): Remove w_drem.
* sysdeps/ieee754/ldbl-opt/Makefile (libnldbl-calls): Remove drem.
(CFLAGS-nldbl-drem.c): Remove variable.
(CFLAGS-nldbl-remainder.c): Add -fno-builtin-dreml.
* math/w_drem.c: Remove file.
* math/w_dremf.c: Likewise.
* math/w_dreml.c: Likewise.
* sysdeps/ieee754/ldbl-opt/nldbl-drem.c: Likewise.
* sysdeps/ieee754/ldbl-opt/w_drem.c: Likewise.
* sysdeps/ieee754/ldbl-opt/w_dreml.c: Likewise.
fenv_t should include architecture-specific floating-point modes and
status flags. i386 and x86_64 fesetenv limit which bits they use from
the x87 status and control words, when using saved state, and limit
which parts of the state they set to fixed values, when using
FE_DFL_ENV / FE_NOMASK_ENV. The following should be included but are
excluded in at least some cases: status and masking for the "denormal
operand" exception (which isn't part of FE_ALL_EXCEPT); precision
control (explicitly mentioned in Annex F as something that counts as
part of the floating-point environment); MXCSR FZ and DAZ bits (for
FE_DFL_ENV and FE_NOMASK_ENV). This patch arranges for this extra
state to be handled by fesetenv (and thereby by feupdateenv, which
calls fesetenv).
(Note that glibc functions using floating point are not generally
expected to work correctly with non-default values of this state,
especially precision control, but it is still logically part of the
floating-point environment and should be handled as such by fesetenv.
Changes to the state relating to subnormals ought generally to work
with libm functions when the arguments aren't subnormal and neither
are the expected results; that's a consequence of functions avoiding
spurious internal underflows.)
A question arising from this is whether FE_NOMASK_ENV should or should
not mask the "denormal operand" exception. I decided it should mask
that exception. This is the status quo - previously that exception
could only be unmasked by direct manipulation of control registers
(possibly via <fpu_control.h>). In addition, it means that use of
FE_NOMASK_ENV leaves a floating-point environment the same as could be
obtained by fesetenv (FE_DFL_ENV); feenableexcept (FE_ALL_EXCEPT);,
rather than an environment in which an exception is unmasked that
could only be masked again by using fesetenv with FE_DFL_ENV (or a
previously saved environment) - this exception not being usable with
other <fenv.h> functions because it's outside FE_ALL_EXCEPT.
Tested for x86_64 and x86.
[BZ #16068]
* sysdeps/i386/fpu/fesetenv.c: Include <fpu_control.h>.
(FE_ALL_EXCEPT_X86): New macro.
(__fesetenv): Use FE_ALL_EXCEPT_X86 in most places instead of
FE_ALL_EXCEPT. Ensure precision control is included in
floating-point state. Ensure that FE_DFL_ENV and FE_NOMASK_ENV
handle "denormal operand exception" and clear FZ and DAZ bits.
* sysdeps/x86_64/fpu/fesetenv.c: Include <fpu_control.h>.
(FE_ALL_EXCEPT_X86): New macro.
(__fesetenv): Use FE_ALL_EXCEPT_X86 in most places instead of
FE_ALL_EXCEPT. Ensure precision control is included in
floating-point state. Ensure that FE_DFL_ENV and FE_NOMASK_ENV
handle "denormal operand exception" and clear FZ and DAZ bits.
* sysdeps/x86/fpu/test-fenv-sse-2.c: New file.
* sysdeps/x86/fpu/test-fenv-x87.c: Likewise.
* sysdeps/x86/fpu/Makefile [$(subdir) = math] (tests): Add
test-fenv-x87 and test-fenv-sse-2.
[$(subdir) = math] (CFLAGS-test-fenv-sse-2.c): New variable.
The i386 and x86_64 versions of fesetenv, when called with FE_DFL_ENV
or FE_NOMASK_ENV as argument, do not clear SSE exceptions raised in
MXCSR. These arguments should, like other fenv_t values, represent
the whole of the floating-point state, so such exceptions should be
cleared; this patch adds the required clearing. (Discovered while
working on bug 16068.)
Tested for x86_64 and x86.
[BZ #19181]
* sysdeps/i386/fpu/fesetenv.c (__fesetenv): Clear already-raised
SSE exceptions when argument is FE_DFL_ENV or FE_NOMASK_ENV.
* sysdeps/x86_64/fpu/fesetenv.c (__fesetenv): Likewise.
* math/test-fenv-clear-main.c: New file.
* math/test-fenv-clear.c: Likewise.
* math/Makefile (tests): Add test-fenv-clear.
* sysdeps/x86/fpu/test-fenv-clear-sse.c: New file.
* sysdeps/x86/fpu/Makefile [$(subdir) = math] (tests): Add
test-fenv-clear-sse.
[$(subdir) = math] (CFLAGS-test-fenv-clear-sse.c): New variable.
MIPS16 atomics used __sync_* with GCC before 4.7, which as noted in
bug 17404 is missing the required barrier semantics for
atomic_exchange_rel. This patch removes the code in question as dead
now GCC before 4.7 is no longer supported for building glibc.
Sanity tested with builds for MIPS.
[BZ #17404]
* sysdeps/mips/atomic-machine.h
[__GNUC_PREREQ (4, 8) || (__mips16 && __GNUC_PREREQ (4, 7))]:
Change conditional to [__GNUC_PREREQ (4, 8) || __mips16].
[__mips16 && !__GNUC_PREREQ (4, 7)]: Remove conditional code.
The skip_lock_out_of_tbegin_retries adaptive parameter was
not being used correctly, nor as described. This prevents
a fallback for all users of the lock if a transient abort
occurs within the accepted number of retries.
[BZ #19174]
* sysdeps/powerpc/nptl/elide.h (__elide_lock): Fix usage of
.skip_lock_out_of_tbegin_retries.
* sysdeps/unix/sysv/linux/powerpc/elision-lock.c
(__lll_lock_elision): Likewise, and respect a value of
try_tbegin <= 0.
This patch implements a requirement of GCC 4.7 or later to build
glibc.
This was discussed in the thread starting at
<https://sourceware.org/ml/libc-alpha/2015-08/msg00851.html>.
Concerns were expressed by Mike and David. At
<https://sourceware.org/ml/libc-alpha/2015-10/msg00453.html> I have
provided a 14-patch series showing in outline the cleanups facilitated
by this version requirement, as requested by Mike (this patch is the
first in that series, with the addition of a NEWS entry). Given the
absence of further concerns or alternative proposals for criteria for
updates to this version requirement as requested in
<https://sourceware.org/ml/libc-alpha/2015-10/msg00065.html>, I am
interpreting this as "absence of sustained opposition" under Carlos's
definition at <https://sourceware.org/glibc/wiki/Consensus> and
proposing this patch for inclusion in glibc. I'd like to remind
people testing with 4.6 that if they move to testing with GCC 5 then
it will probably be about four years before they need to update the
compiler they use to test glibc again.
Although on the principles of time-based updates I think a move to
requiring binutils 2.23 would be reasonable, I'm not currently aware
of any cleanups that would facilitate so am not proposing that at this
time (but would expect to propose a move to requiring binutils 2.24 in
a year's time, as that brings features such as AVX512 support that
should allow some conditionals to be cleaned up). If someone thinks a
move to requiring 2.23 would help clean things up for their
architecture, please speak up. (And in general, I suspect there are
lots of architecture-specific configure tests that could be removed on
the basis of current GCC and binutils version requirements, given how
I've found architecture-independent tests obsolete on the basis of
version requirements going back 20 years.)
Tested for x86_64 and x86 (testsuite, and that installed shared
libraries are unchanged by the patch).
* configure.ac (libc_cv_compiler_ok): Require GCC 4.7 or later.
* configure: Regenerated.
* manual/install.texi (Tools for Compilation): Document
requirement for GCC 4.7 or later.
* INSTALL: Regenerated.
j1 and jn can underflow for small arguments, but fail to set errno
when underflowing to 0. This patch fixes them to set errno in that
case.
Tested for x86_64, x86, mips64 and powerpc.
[BZ #18611]
* sysdeps/ieee754/dbl-64/e_j1.c (__ieee754_j1): Set errno and
avoid excess range and precision on underflow.
* sysdeps/ieee754/dbl-64/e_jn.c (__ieee754_jn): Likewise.
* sysdeps/ieee754/flt-32/e_j1f.c (__ieee754_j1f): Likewise.
* sysdeps/ieee754/flt-32/e_jnf.c (__ieee754_jnf): Likewise.
* sysdeps/ieee754/ldbl-128/e_j1l.c (__ieee754_j1l): Set errno on
underflow.
* sysdeps/ieee754/ldbl-128/e_jnl.c (__ieee754_jnl): Likewise.
* sysdeps/ieee754/ldbl-128ibm/e_jnl.c (__ieee754_jnl): Likewise.
* sysdeps/ieee754/ldbl-96/e_j1l.c (__ieee754_j1l): Likewise.
* sysdeps/ieee754/ldbl-96/e_jnl.c (__ieee754_jnl): Likewise.
* math/auto-libm-test-in: Do not allow missing errno setting for
tests of j1 and jn.
* math/auto-libm-test-out: Regenerated.
The implementations of nearbyint functions using x87 floating point
(i386 all versions, x86_64 long double only) use the fclex
instruction, which clears any exceptions that were raised before the
function was called. These functions must not clear exceptions that
were raised before they were called.
This patch fixes these functions to save and restore the whole
floating-point environment (fnstenv / fldenv) as the way of avoiding
raising "inexact" (recall that there isn't an x87 instruction for
loading just the status word, so the whole environment has to be saved
and loaded instead - the code already saved and loaded the control
word, which is now obtained from the saved environment after this
patch, to disable traps on "inexact"). In the case of the long double
functions, any "invalid" exception from frndint (applied to a
signaling NaN) needs merging into the saved state; this issue doesn't
apply to the float and double functions because that exception would
have been raised when the argument is loaded, before the environment
is saved.
[BZ #15491]
* sysdeps/i386/fpu/s_nearbyint.S (__nearbyint): Save and restore
floating-point environment instead of clearing all exceptions.
* sysdeps/i386/fpu/s_nearbyintf.S (__nearbyintf): Likewise.
* sysdeps/i386/fpu/s_nearbyintl.S (__nearbyintl): Likewise,
merging in "invalid" exceptions from frndint.
* sysdeps/x86_64/fpu/s_nearbyintl.S (__nearbyintl): Likewise.
* math/test-nearbyint-except.c: New file.
* math/Makefile (tests): Add test-nearbyint-except.
Wilco fixed this tilegx bug in commit fe8c2b33ae ("Since we
now inline isinf, isnan and isfinite in math.h, replace uses
of __isinf_ns(l/f) with isinf, and remove the unused inlines
__isinf_ns(l/f), __isnan(f) and __finite(f).")
I verified that reverting math/s_cprojf.c back to using the
sysdeps/ieee754/flt-32/math_private.h version of __isinf_nsf()
instead of isinf() brings back the bug on tilegx.
My recent addition of more tests for j0 showed up that the ldbl-128
implementation of j0l produces spurious underflow exceptions for
arguments close to 0 (when the result is very close to 1). This patch
fixes this by just returning the argument in that case.
Tested for mips64 (where it fixes the recently-added tests that were
previously failing).
[BZ #19156]
* sysdeps/ieee754/ldbl-128/e_j0l.c (__ieee754_j0l): Return 1 for
arguments very close to 0.
The previous code used to evaluate the preprocessor token is_lock_free to
a variable before starting a transaction. This behavior can cause an
error if another thread got the lock (without using a transaction)
between the evaluation of the token and the beginning of the transaction.
This bug can be triggered with the following order of events:
1. The lock accessed by is_lock_free is free.
2. Thread T1 evaluates is_lock_free and stores into register R1 that the
lock is free.
3. Thread T2 acquires the same lock used in is_lock_free.
4. T1 begins the transaction, creating a memory barrier where is_lock_free
is false, but R1 is true.
5. T1 reads R1 and doesn't abort the transaction.
6. T1 calls ELIDE_UNLOCK, which reads false from is_lock_free and decides
to unlock a lock acquired by T2, leading to undefined behavior.
This patch delays the evaluation of is_lock_free to inside a transaction
by moving this part of the code to the macro ELIDE_LOCK.
[BZ #18743]
* sysdeps/powerpc/nptl/elide.h (__elide_lock): Move most of this
code to...
(ELIDE_LOCK): ...here.
(__get_new_count): New function with part of the code from
__elide_lock that updates the value of adapt_count after a
transaction abort.
(__elided_trylock): Moved this code to...
(ELIDE_TRYLOCK): ...here.
The previous (11th) version of the Hungarian spelling rules (released
in 1984) said that the separator had to be a dot, e.g. 10.35 meaning
10 o'clock 35 minutes. glibc correctly implements this.
The brand new (12th) version, in effect since September 1, 2015 adopts
to the common use of colon (especially in the digital world) and
allows to use either separator, without even expressing a preference.
For computer systems, using colons is way more typical and probably
easier to recognize. Dot is typically used in printed materials.
It also avoids an almost ambiguous situation where a space makes a
difference, e.g. "10.15-ig" means "until 10 o'clock 15 minutes"
whereas "10. 15-ig" means "until 15th of October". So I believe using
the colon as the separator is not only more frequent in the computer
world, but is also easier and quicker to recognize for the brain that
it's about hour:minute rather than month and day. And luckily it's now
equally correct according to the official rules.
11th edition: http://helyesiras.mta.hu/helyesiras/default/akh11
12th edition: http://helyesiras.mta.hu/helyesiras/default/akh12
In both editions it's the very last (299th and 300th, respectively) rule.
Microsoft also uses and recommends a colon since at least May 2011:
http://download.microsoft.com/download/e/6/1/e61266b2-d8b4-4fe0-a553-f01dc3976675/hun-hun-StyleGuide.pdf
The time format is different in common language and in the language of
IT. In common texts we usually do not abbreviate, so the full forms are
used: “7 óra 10 perckor csörgött a telefon”. However, the short format,
consisting of numerals only, can also be used. In this case a period
must be used between the two numbers and there must not be a space
between them: “találkozzunk 10.45-kor”.
However, in software mostly the short format is used, and the numbers
are separated by a colon. An obvious example is the clock in the bottom
right corner of your screen, thus 18:31.
Only i386 implements epoll_pwait in assembly code withot cancellation
support. All other architectures implement epoll_pwait in epoll_pwait.c
with
int epoll_pwait (int epfd, struct epoll_event *events,
int maxevents, int timeout,
const sigset_t *set)
{
return SYSCALL_CANCEL (epoll_pwait, epfd, events, maxevents,
timeout, set, _NSIG / 8);
}
Although there is no test for epoll_pwait in glibc, since SYSCALL_CANCEL
works on i386 and epoll_pwait.c works for other architectures, it is
safe to assume that epoll_pwait.c with SYSCALL_CANCEL also works on
i386.
[BZ #19137]
* sysdeps/unix/sysv/linux/i386/Makefile (CFLAGS-epoll_pwait.c):
Add -fomit-frame-pointer.
* sysdeps/unix/sysv/linux/i386/epoll_pwait.S: Remove file.
Honoring the LD_POINTER_GUARD environment variable in AT_SECURE mode
has security implications. This commit enables pointer guard
unconditionally, and the environment variable is now ignored.
[BZ #18928]
* sysdeps/generic/ldsodefs.h (struct rtld_global_ro): Remove
_dl_pointer_guard member.
* elf/rtld.c (_rtld_global_ro): Remove _dl_pointer_guard
initializer.
(security_init): Always set up pointer guard.
(process_envvars): Do not process LD_POINTER_GUARD.
The powerpc32 implementation of lround and lroundf can produce
spurious exceptions from adding 0.5 then converting to integer. This
includes "inexact" from the conversion to integer (not allowed for
integer arguments to these functions), and, for larger integer
arguments, "inexact", and "overflow" when rounding upward, from the
addition. In addition, "inexact" is not allowed together with
"invalid" and so inexact addition must be avoided when the integer
will be out of range of 32-bit long, whether or not the argument is an
integer.
This patch fixes these problems. As in the powerpc64 llround
implementation, a check is added for too-large arguments; in the
powerpc64 case that means arguments at least 2^52 in magnitude (so
that 0.5 cannot be added exactly), while in this case it means
arguments for which the result would overflow "long". In those cases
a suitable overflowing value is used for the integer conversion
without adding 0.5, while for smaller arguments it's tested whether
the argument is an integer (by adding and subtracting 2^52 to the
absolute value and comparing with the original absolute value) to
avoid adding 0.5 to integers and generating spurious "inexact".
This code is not used when the power5+ sysdeps directories are used,
as there's a separate power5+ version of these functions..
Tested for powerpc. This gets test-float (for a default powerpc32
hard-float build without any --with-cpu) back to the point where it
should pass once powerpc ulps are regenerated; test-double still needs
another problem with exceptions fixed to get back to that point (and I
haven't looked lately at what default powerpc64 results are like).
[BZ #19134]
* sysdeps/powerpc/powerpc32/fpu/s_lround.S (.LC1): New object.
(.LC2): Likewise.
(.LC3): Likewise.
(__lround): Do not add 0.5 to integer or out-of-range arguments.
_dl_tlsdesc_resolve_hold calls into a C function that clobbers r0,
but it assumes the original argument is still in r0 after the call.
This can cause crash in case of concurrent TLS access when TLSDESC
is in use (-mtls-dialect=gnu2).
Run into this while fixing BZ 18572.
Both r0 and r1 are saved/restored so the stack remains 8 byte aligned.
[BZ #19129]
* sysdeps/arm/dl-tlsdesc.S (_dl_tlsdesc_resolve_hold): Save and restore
r0 and r1.
Linker in binutils 2.26 and newer generate GOT references instead
PLT references when -z now is passed to linker. We need to extend
scripts/localplt.awk to allow PLT or GOT references.
[BZ #19007]
* scripts/localplt.awk: Also allow GOT references.
* sysdeps/unix/sysv/linux/i386/localplt.data: Mark
_Unwind_Find_FDE, calloc, memalign, realloc and __libc_memalign
with "+ REL R_386_GLOB_DAT".
* sysdeps/x86_64/localplt.data: Mark calloc, memalign, realloc
and __libc_memalign with "+ RELA R_X86_64_GLOB_DAT".
The powerpc32 implementations of llroundf and llround produce spurious
and missing exceptions (some arising from such exceptions from
conversions to long long, some present even when fctidz is used).
This patch fixes those problems in a similar way to the llrint /
llrintf fixes. The spurious exceptions in the fctidz case for large
arguments arise from a converted value that saturated as LLONG_MAX
being converted back to float or double (the conversion back being
inexact, but "inexact" must not be raised together with "invalid"),
and from the subtraction x - xrf also being inexact for sufficiently
large arguments (whether the saturation was to LLONG_MAX or
LLONG_MIN); those are fixed by returning early if the argument is
large enough that no rounding is needed.
This code is not used for --with-cpu=power4 builds (I suspect the code
used in that case may also produce spurious "inexact" exceptions, but
that's something to investigate later).
Tested for powerpc.
[BZ #19125]
* sysdeps/powerpc/powerpc32/fpu/s_llround.c: Include <limits.h>,
<math_private.h> and <stdint.h>.
(__llround): Avoid conversions to and from long long int, and
subtractions, where those might raise spurious exceptions.
* sysdeps/powerpc/powerpc32/fpu/s_llroundf.c: Include
<math_private.h> and <stdint.h>.
(__llroundf): Avoid conversions to and from long long int, and
subtractions, where those might raise spurious exceptions.
When x86-64 assmebler doesn't support AVX512, we should make
_dl_runtime_resolve_avx512/_dl_runtime_profile_avx512 as aliases of
_dl_runtime_resolve_avx/_dl_runtime_profile_avx. Tested on x86-64
using GCC 5.2 with binutils 20151008 and GCC 4.8 with binutils 20130219.
There are no differences in ld.so with binutils 20151008. There are no
unexpected failures with binutils 20130219 and 20151008.
[BZ #19124]
* sysdeps/x86_64/dl-trampoline.S [!HAVE_AVX512_ASM_SUPPORT]
(_dl_runtime_resolve_avx512): Make it a hidden alias of
_dl_runtime_resolve_avx.
(_dl_runtime_profile_avx512): Make it a hidden alias of
_dl_runtime_profile_avx.
The versions of llrint and llrintf for older powerpc32 processors
convert the results of __rint / __rintf to long long int, resulting in
spurious exceptions from such casts in certain cases. This patch
makes glibc work around the problems with the libgcc conversions when
the compiler used to build glibc doesn't use the fctidz instruction
for them.
Tested for powerpc.
[BZ #16422]
* sysdeps/powerpc/powerpc32/fpu/configure.ac (libc_cv_ppc_fctidz):
New configure test.
* sysdeps/powerpc/powerpc32/fpu/configure: Regenerated.
* config.h.in [_LIBC] (HAVE_PPC_FCTIDZ): New macro.
* sysdeps/powerpc/powerpc32/fpu/s_llrint.c: Include <limits.h>,
<math_private.h> and <stdint.h>.
(__llrint): Avoid conversions to long long int where those might
raise spurious exceptions.
* sysdeps/powerpc/powerpc32/fpu/s_llrintf.c: Include
<math_private.h> and <stdint.h>.
(__llrintf): Avoid conversions to long long int where those might
raise spurious exceptions.
Similar to the recent fix for MIPS, ARM is also missing correct
exceptions on overflow from llrint and llround functions because casts
from floating-point types to long long do not result in correct
exceptions on overflow. This patch enables the fix for this for ARM.
Tested for ARM.
[BZ #15470]
* sysdeps/arm/fix-fp-int-convert-overflow.h: New file.
For 32-bit MIPS and some other systems, various of the lrint, llrint,
lround, llround functions can be missing exceptions on overflow
because casts do not (in current GCC) result in the proper
exceptions. In the MIPS case there are two problems here: MIPS I code
generation uses an assembler macro that doesn't raise exceptions,
while the libgcc conversions of floating-point values to long long
also do not raise "invalid" on all overflow cases (and can raise
spurious "inexact").
This patch adds support in the generic code (only the functions for
which this problem has actually been seen) for forcing the "invalid"
exception in the problem cases, and enables that support for the
affected MIPS cases.
Tested for MIPS; also tested for x86_64 and x86 that installed
stripped shared libraries are unchanged by this patch.
[BZ #16399]
* sysdeps/generic/fix-fp-int-convert-overflow.h: New file.
* sysdeps/ieee754/dbl-64/s_llrint.c: Include <fenv.h>, <limits.h>
and <fix-fp-int-convert-overflow.h>.
(__llrint) [FE_INVALID]: Force FE_INVALID exception as needed if
FIX_DBL_LLONG_CONVERT_OVERFLOW.
* sysdeps/ieee754/dbl-64/s_llround.c: Include <fenv.h>, <limits.h>
and <fix-fp-int-convert-overflow.h>.
(__llround) [FE_INVALID]: Force FE_INVALID exception as needed if
FIX_DBL_LLONG_CONVERT_OVERFLOW.
* sysdeps/ieee754/dbl-64/s_lrint.c: Include
<fix-fp-int-convert-overflow.h>.
(__lrint) [FE_INVALID]: Force FE_INVALID exception as needed if
FIX_DBL_LLONG_CONVERT_OVERFLOW.
* sysdeps/ieee754/dbl-64/s_lround.c: Include
<fix-fp-int-convert-overflow.h>.
(__lround) [FE_INVALID]: Force FE_INVALID exception as needed if
FIX_DBL_LLONG_CONVERT_OVERFLOW.
* sysdeps/ieee754/flt-32/s_llrintf.c: Include <fenv.h>, <limits.h>
and <fix-fp-int-convert-overflow.h>.
(__llrintf) [FE_INVALID]: Force FE_INVALID exception as needed if
FIX_DBL_LLONG_CONVERT_OVERFLOW.
* sysdeps/ieee754/flt-32/s_llroundf.c: Include <fenv.h>,
<limits.h> and <fix-fp-int-convert-overflow.h>.
(__llroundf) [FE_INVALID]: Force FE_INVALID exception as needed if
FIX_DBL_LLONG_CONVERT_OVERFLOW.
* sysdeps/ieee754/flt-32/s_lrintf.c: Include <fenv.h>, <limits.h>
and <fix-fp-int-convert-overflow.h>.
(__lrintf) [FE_INVALID]: Force FE_INVALID exception as needed if
FIX_DBL_LLONG_CONVERT_OVERFLOW.
* sysdeps/ieee754/flt-32/s_lroundf.c: Include <fenv.h>, <limits.h>
and <fix-fp-int-convert-overflow.h>.
(__lroundf) [FE_INVALID]: Force FE_INVALID exception as needed if
FIX_DBL_LLONG_CONVERT_OVERFLOW.
* sysdeps/mips/mips32/fpu/fix-fp-int-convert-overflow.h: New file.
The dbl-64 implementation of lrint produces incorrect results for some
arguments with 64-bit long because a 32-bit (unsigned) low part of the
mantissa is shifted left, losing high bits in the process. This patch
fixes this by casting to long int before shifting, as in lround (as
this case only applies for 64-bit long, there are no issues with
sign-extension).
Tested for mips64 (n64).
[BZ #19095]
* sysdeps/ieee754/dbl-64/s_lrint.c (__lrint): Cast low part of
mantissa to long int before shifting left.
The dbl-64, ldbl-96 and ldbl-128 implementations of lrint and llrint
fail to produce "invalid" exceptions in cases where the rounded result
overflows the target type, but truncating the floating-point argument
to the next integer towards zero does not overflow it (so in
particular casts do not produce such exceptions). (This issue cannot
arise for float, or for double with 64-bit target type, or for ldbl-96
with 64-bit target type and negative arguments, because of
insufficient precision in the floating-point type for arguments with
the relevant property to exist. It also obviously cannot arise in
FE_TOWARDZERO mode.)
This patch fixes these problems by inserting checks for the special
cases that can occur in each implementation, and explicitly raising
FE_INVALID (and avoiding the cast if it might raise spurious
FE_INEXACT, while raising FE_INEXACT explicitly in the cases where it
is needed; unlike lround and llround, FE_INEXACT is required, not
optional, for these functions for a within-range inexact result).
The fixes are conditional on FE_INVALID or FE_INEXACT being defined.
If any future architecture supports one but not both of those
exceptions, the code will fail to compile and need fixing to handle
that case (this seemed better than conditioning on both macros being
defined, resulting in code that would compile but quietly miss
exceptions on such a system).
Tested for x86_64, x86 and mips64. Tested the ldbl-96 changes (only
relevant for ia64, it appears) on x86_64 by removing the x86_64
versions of lrintl / llrintl.
[BZ #19094]
* sysdeps/ieee754/dbl-64/s_lrint.c: Include <fenv.h> and
<limits.h>.
(__lrint) [FE_INVALID || FE_INEXACT]: Force FE_INVALID exception
when result overflows but exception would not result from cast.
* sysdeps/ieee754/ldbl-128/s_llrintl.c: Include <fenv.h> and
<limits.h>.
(__llrintl) [FE_INVALID || FE_INEXACT]: Force FE_INVALID exception
when result overflows but exception would not result from cast.
* sysdeps/ieee754/ldbl-128/s_lrintl.c: Include <fenv.h> and
<limits.h>.
(__lrintl) [FE_INVALID || FE_INEXACT]: Force FE_INVALID exception
when result overflows but exception would not result from cast.
* sysdeps/ieee754/ldbl-96/s_llrintl.c: Include <fenv.h> and
<limits.h>.
(__llrintl) [FE_INVALID || FE_INEXACT]: Force FE_INVALID exception
when result overflows but exception would not result from cast.
* sysdeps/ieee754/ldbl-96/s_lrintl.c: Include <fenv.h> and
<limits.h>.
(__lrintl) [FE_INVALID || FE_INEXACT]: Force FE_INVALID exception
when result overflows but exception would not result from cast.
* math/libm-test.inc (lrint_test_data): Add more tests.
(llrint_test_data): Likewise.
The optimization introduced in commit
f13c2a8dff, causes regressions in
sorting for languages that have digraphs that change sort order, like
cs_CZ which sorts ch between h and i.
My analysis shows the fast-forwarding optimization in STRCOLL advances
through a digraph while possibly stopping in the middle which results
in a subsequent skipping of the digraph and incorrect sorting. The
optimization is incorrect as implemented and because of that I'm
removing it for 2.23, and I will also commit this fix for 2.22 where
it was originally introduced.
This patch reverts the optimization, introduces a new bug-strcoll2.c
regression test that tests both cs_CZ.UTF-8 and da_DK.ISO-8859-1 and
ensures they sort one digraph each correctly. The optimization can't be
applied without regressing this test.
Checked on x86_64, bug-strcoll2.c fails without this patch and passes
after. This will also get a fix on 2.22 which has the same bug.
The dbl-64, ldbl-96 and ldbl-128 implementations of lround and llround
fail to produce "invalid" exceptions in cases where the rounded result
overflows the target type, but truncating the floating-point argument
to the next integer towards zero does not overflow it (so in
particular casts do not produce such exceptions). (This issue cannot
arise for float, or for double with 64-bit target type, or for ldbl-96
with 64-bit target type and negative arguments, because of
insufficient precision in the floating-point type for arguments with
the relevant property to exist.)
This patch fixes these problems by inserting checks for the special
cases that can occur in each implementation, and explicitly raising
FE_INVALID (and avoiding the cast if it might raise spurious
FE_INEXACT).
Tested for x86_64, x86 and mips64.
[BZ #19088]
* sysdeps/ieee754/dbl-64/s_lround.c: Include <fenv.h> and
<limits.h>.
(__lround) [FE_INVALID]: Force FE_INVALID exception when result
overflows but exception would not result from cast.
* sysdeps/ieee754/dbl-64/wordsize-64/s_lround.c: Include <fenv.h>
and <limits.h>.
(__lround) [FE_INVALID]: Force FE_INVALID exception when result
overflows but exception would not result from cast.
* sysdeps/ieee754/ldbl-128/s_llroundl.c: Include <fenv.h> and
<limits.h>.
(__llroundl) [FE_INVALID]: Force FE_INVALID exception when result
overflows but exception would not result from cast.
* sysdeps/ieee754/ldbl-128/s_lroundl.c: Include <fenv.h> and
<limits.h>.
(__lroundl) [FE_INVALID]: Force FE_INVALID exception when result
overflows but exception would not result from cast.
* sysdeps/ieee754/ldbl-96/s_llroundl.c: Include <fenv.h> and
<limits.h>.
(__llroundl) [FE_INVALID]: Force FE_INVALID exception when result
overflows but exception would not result from cast.
* sysdeps/ieee754/ldbl-96/s_lroundl.c: Include <fenv.h> and
<limits.h>.
(__lroundl) [FE_INVALID]: Force FE_INVALID exception when result
overflows but exception would not result from cast.
* math/libm-test.inc (lround_test_data): Add more tests.
(llround_test_data): Likewise.
The ldbl-128 implementations of lrintl and lroundl miss "invalid"
exceptions on systems with 32-bit long for arguments that overflow
long but have exponent below 48. This patch fixes this by rearranging
the sequence of tests in the code so the exponent < 48 case is only
used for exponents that don't overflow long.
Tested for mips64 (n32 and n64).
[BZ #19085]
* sysdeps/ieee754/ldbl-128/s_lrintl.c (__lrintl): Move test for
exponent below 48 inside case for non-overflowing exponent.
* sysdeps/ieee754/ldbl-128/s_lroundl.c (__lroundl): Likewise.
The implementation of lround in dbl-64/wordsize-64 as an alias or
wrapper for llround is always incorrect when long is not 64-bit,
because it misses required exceptions in overflow cases, as shown by
my recently added tests. This patch removes that alias / wrapper in
the non-LP64 case, together with the REGISTER_CAST_INT32_TO_INT64
macro, restoring the previous version of lround for dbl-64/wordsize-64
(newly conditioned on !_LP64).
Tested for x86_64, and for mips64 with use of dbl-64/wordsize-64
enabled.
[BZ #19079]
* sysdeps/ieee754/dbl-64/wordsize-64/s_lround.c: Restore previous
file, conditioned on [!_LP64].
* sysdeps/ieee754/dbl-64/wordsize-64/s_llround.c
[!_LP64] (__lround): Do not define as function or alias.
[!_LP64] (lround): Likewise.
[!_LP64] (__lroundl): Likewise.
[!_LP64] (lroundl): Likewise.
* sysdeps/tile/sysdep.h (REGISTER_CAST_INT32_TO_INT64): Remove
macro.
* sysdeps/x86_64/x32/sysdep.h (REGISTER_CAST_INT32_TO_INT64):
Likewise.
The ldbl-128ibm expl wrapper checks the argument to determine when to
call __kernel_standard_l, thereby overriding overflowing results from
__ieee754_expl that could otherwise (given appropriately patched
libgcc) be correct for the rounding mode. This patch changes it to
check the result of __ieee754_expl instead, as other versions of this
wrapper do.
Tested for powerpc.
[BZ #19078]
* sysdeps/ieee754/ldbl-128ibm/w_expl.c (o_thres): Remove variable.
(u_thres): Likewise.
(__expl): Determine whether to call __kernel_standard_l based on
value of result, not argument.
The ldbl-128ibm implementation of logl produces a zero with the wrong
sign for logl (1) in FE_DOWNWARD mode. This patch makes it explicitly
return 0.0L in that case, as in e.g. the ldbl-128 implementation.
Tested for powerpc.
[BZ #19077]
* sysdeps/ieee754/ldbl-128ibm/e_logl.c (__ieee754_logl): Return
0.0L for argument 1.0L.
The ldbl-128ibm implementation of log1pl produces an infinity with the
wrong sign for log1pl (-1) in FE_DOWNWARD mode. This patch fixes this
by changing a division (-1.0L / (x - x)) (incorrect in FE_DOWNWARD
mode) to (-1.0L / 0.0L) (correct in all rounding modes).
Tested for powerpc.
[BZ #19076]
* sysdeps/ieee754/ldbl-128ibm/s_log1pl.c (__log1pl): Divide by
constant 0.0L when computing infinite result.
The ldbl-96 version of lroundl is incorrect for systems with 64-bit
long when the argument's absolute value is just below a power of 2,
2^32 or more, and rounds up to the next integer; in such cases, it
returns 0. The problem is incrementing the high part of the mantissa
loses the high bit of the value (which is not an issue for any other
floating-point format, and is handled specially in lround when the bit
corresponding to 0.5 was in the high part rather than the low part).
This patch fixes this in a similar way to that used in llroundl:
storing the high part in an unsigned long variable before incrementing
it, so problems cannot occur in the case when this code is reachable.
I improved test coverage for both lround and llround by making them
use the same test inputs (appropriately conditioned on the size of
long in the lround case) - complete with the same comments, to make
comparison as easy as possible. (This test coverage improvement was
how I found the lroundl bug.)
Tested for x86_64 and x86.
[BZ #19071]
* sysdeps/ieee754/ldbl-96/s_lroundl.c (__lroundl): Use unsigned
long int variable to store possibly incremented high part of
mantissa.
* math/libm-test.inc (lround_test_data): Add tests used for
llround. Use [LONG_MAX > 0x7fffffff] consistently as condition
for tests requiring 64-bit long. Do not condition tests on
[TEST_FLOAT] unnecessarily.
(llround_test_data): Add tests used for lround. Add another
expectation for the "inexact" exception. Do not condition tests
on [TEST_FLOAT] unnecessarily.
On powerpc32 hard-float, older processors (ones where fcfid is not
available for 32-bit code), GCC generates conversions from integers to
floating point that wrongly convert integer 0 to -0 instead of +0 in
FE_DOWNWARD mode. This in turn results in logb and a few other
functions wrongly returning -0 when they should return +0.
This patch works around this issue in glibc as I proposed in
<https://sourceware.org/ml/libc-alpha/2015-09/msg00728.html>, so that
the affected functions can be correct and the affected tests pass in
the absence of a GCC fix for this longstanding issue (GCC bug 67771 -
if fixed, of course we can put in GCC version conditionals, and
eventually phase out the workarounds). A new macro
FIX_INT_FP_CONVERT_ZERO is added in a new sysdeps header
fix-int-fp-convert-zero.h, and the powerpc32/fpu version of that
header defines the macro based on the results of a configure test for
whether such conversions use the fcfid instruction.
Tested for x86_64 (that installed stripped shared libraries are
unchanged by the patch) and powerpc (that HAVE_PPC_FCFID comes out to
0 as expected and that the relevant tests are fixed). Also tested a
build with GCC configured for -mcpu=power4 and verified that
HAVE_PPC_FCFID comes out to 1 in that case.
There are still some other issues to fix to get test-float and
test-double passing cleanly for older powerpc32 processors (apart from
the need for an ulps regeneration for powerpc). (test-ldouble will be
harder to get passing cleanly, but with a combination of selected
fixes to ldbl-128ibm code that don't involve significant performance
issues, allowing spurious underflow and inexact exceptions for that
format, and lots of XFAILing for the default case of unpatched libgcc,
it should be doable.)
[BZ #887]
[BZ #19049]
[BZ #19050]
* sysdeps/generic/fix-int-fp-convert-zero.h: New file.
* sysdeps/ieee754/dbl-64/e_log10.c: Include
<fix-int-fp-convert-zero.h>.
(__ieee754_log10): Adjust signs as needed if FIX_INT_FP_CONVERT_ZERO.
* sysdeps/ieee754/dbl-64/e_log2.c: Include
<fix-int-fp-convert-zero.h>.
(__ieee754_log2): Adjust signs as needed if FIX_INT_FP_CONVERT_ZERO.
* sysdeps/ieee754/dbl-64/s_erf.c: Include
<fix-int-fp-convert-zero.h>.
(__erfc): Adjust signs as needed if FIX_INT_FP_CONVERT_ZERO.
* sysdeps/ieee754/dbl-64/s_logb.c: Include
<fix-int-fp-convert-zero.h>.
(__logb): Adjust signs as needed if FIX_INT_FP_CONVERT_ZERO.
* sysdeps/ieee754/flt-32/e_log10f.c: Include
<fix-int-fp-convert-zero.h>.
(__ieee754_log10f): Adjust signs as needed if FIX_INT_FP_CONVERT_ZERO.
* sysdeps/ieee754/flt-32/e_log2f.c: Include
<fix-int-fp-convert-zero.h>.
(__ieee754_log2f): Adjust signs as needed if FIX_INT_FP_CONVERT_ZERO.
* sysdeps/ieee754/flt-32/s_erff.c: Include
<fix-int-fp-convert-zero.h>.
(__erfcf): Adjust signs as needed if FIX_INT_FP_CONVERT_ZERO.
* sysdeps/ieee754/flt-32/s_logbf.c: Include
<fix-int-fp-convert-zero.h>.
(__logbf): Adjust signs as needed if FIX_INT_FP_CONVERT_ZERO.
* sysdeps/ieee754/ldbl-128ibm/s_erfl.c: Include
<fix-int-fp-convert-zero.h>.
(__erfcl): Adjust signs as needed if FIX_INT_FP_CONVERT_ZERO.
* sysdeps/ieee754/ldbl-128ibm/s_logbl.c: Include
<fix-int-fp-convert-zero.h>.
(__logbl): Adjust signs as needed if FIX_INT_FP_CONVERT_ZERO.
* sysdeps/powerpc/powerpc32/fpu/configure.ac: New file.
* sysdeps/powerpc/powerpc32/fpu/configure: New generated file.
* sysdeps/powerpc/powerpc32/fpu/fix-int-fp-convert-zero.h: New
file.
* config.h.in [_LIBC] (HAVE_PPC_FCFID): New macro.
ISO C requires overflowing results from nexttoward to be the
appropriate infinity independent of the rounding mode, but some
implementations use a rounding-mode-dependent result (this is the same
issue as was fixed for nextafter in bug 16677). This patch fixes the
problem by making the nexttoward implementations discard the result
from the floating-point computation that forced an overflow exception
and then return the infinity previously computed with integer
arithmetic.
Tested for x86_64, x86, mips64 and powerpc.
[BZ #19059]
* math/s_nexttowardf.c (__nexttowardf): Do not return value from
overflowing computation.
* sysdeps/i386/fpu/s_nexttoward.c (__nexttoward): Likewise.
* sysdeps/i386/fpu/s_nexttowardf.c (__nexttowardf): Likewise.
* sysdeps/ieee754/ldbl-128/s_nexttoward.c (__nexttoward):
Likewise.
* sysdeps/ieee754/ldbl-128/s_nexttowardf.c (__nexttowardf):
Likewise.
* sysdeps/ieee754/ldbl-128ibm/s_nexttoward.c (__nexttoward):
Likewise.
* sysdeps/ieee754/ldbl-128ibm/s_nexttowardf.c (__nexttowardf):
Likewise.
* sysdeps/ieee754/ldbl-96/s_nexttoward.c (__nexttoward): Likewise.
* sysdeps/ieee754/ldbl-96/s_nexttowardf.c (__nexttowardf):
Likewise.
* sysdeps/ieee754/ldbl-opt/s_nexttowardfd.c (__nldbl_nexttowardf):
Likewise.
* math/libm-test.inc (nexttoward_test_data): Add more tests.
This prevents injection of ':' and '\n' into output functions which
use the NSS files database syntax. Critical fields (user/group names
and file system paths) are checked strictly. For backwards
compatibility, the GECOS field is rewritten instead.
The getent program is adjusted to use the put*ent functions in libc,
instead of local copies. This changes the behavior of getent if user
names start with '-' or '+'.
The ldbl-128 / ldbl-128ibm implementation of lgamma has problems with
its handling of large arguments. It has an overflow threshold that is
correct only for ldbl-128, despite being used for both types - with
diagnostic control macros as a temporary measure to disable warnings
about that constant overflowing for ldbl-128ibm - and it has a
calculation that's roughly x * log(x) - x, resulting in overflows for
arguments that are roughly at most a factor 1/log(threshold) below the
overflow threshold.
This patch fixes both issues, using an overflow threshold appropriate
for the type in question and adding another case for large arguments
that avoids the possible intermediate overflow.
Tested for x86_64, x86, mips64 and powerpc.
[BZ #16347]
[BZ #19046]
* sysdeps/ieee754/ldbl-128/e_lgammal_r.c: Do not include
<libc-internal.h>.
(MAXLGM): Do not use diagnostic control macros.
[LDBL_MANT_DIG == 106] (MAXLGM): Change value to overflow
threshold for ldbl-128ibm.
(__ieee754_lgammal_r): For large arguments, multiply by log - 1
instead of multiplying by log then subtracting.
* math/auto-libm-test-in: Add more tests of lgamma.
* math/auto-libm-test-out: Regenerated.
The ldbl-128ibm implementation of exp10l uses a version of log(10)
split into high and low parts - but the low part is negative, so
causing spurious overflows from __ieee754_expl (exp_high) in cases
close to the overflow threshold (I added relevant tests close to the
overflow threshold to the testsuite earlier today). The same issue
applies close to the underflow threshold as well (except that spurious
underflows in IBM long double arithmetic are harder to fix than the
other deficiencies, so we might end up permitting those for IBM long
double in the libm testsuite, as permitted by ISO C).
This patch fixes it to use a low part rounded downward to 48 bits
instead. (The choice of 48 instead of 53 bits is to make it more
obviously safe even when the low part of the argument is negative.)
Tested for powerpc. (Note that because of libgcc bugs with
multiplication very close to LDBL_MAX, libgcc also needs patching for
all the problem cases to be fixed, but this patch is still safe and
correct in the absence of such libgcc fixes.)
[BZ #16620]
* sysdeps/ieee754/ldbl-128ibm/e_exp10l.c (log10_high): Use value
of log (10) rounded downward to 48 bits.
(log10_low): Use corresponding low part of log (10).
The i386 versions of acoshf and acosh raise a spurious "invalid"
exception for an argument that is a quiet NaN with the sign bit set.
The integer arithmetic to detect arguments < 1 also detects -NaN, and
then the computation 0 / 0 in that case raises the exception. This
patch fixes this by using (x - x) / (x - x) as the computation in that
case instead, which will always raise the exception for non-NaN
arguments reaching that code, but not for quiet NaN arguments.
Tested for x86_64 and x86.
[BZ #19032]
* sysdeps/i386/fpu/e_acosh.S (__ieee754_acosh): For arguments < 1,
compute result as (x - x) / (x - x) not as 0 / 0.
* sysdeps/i386/fpu/e_acoshf.S (__ieee754_acoshf): Likewise.
* math/libm-test.inc (acosh_test_data): Add another test of acosh.
For arguments with X^2 + Y^2 close to 1, clog and clog10 avoid large
errors from log(hypot) by computing X^2 + Y^2 - 1 in a way that avoids
cancellation error and then using log1p.
However, the thresholds for using that approach still result in log
being used on argument as large as sqrt(13/16) > 0.9, leading to
significant errors, in some cases above the 9ulp maximum allowed in
glibc libm. This patch arranges for the approach using log1p to be
used in any cases where |X|, |Y| < 1 and X^2 + Y^2 >= 0.5 (with the
existing allowance for cases where one of X and Y is very small),
adjusting the __x2y2m1 functions to work with the wider range of
inputs. This way, log only gets used on arguments below sqrt(1/2) (or
substantially above 1), where the error involved is much less.
Tested for x86_64, x86, mips64 and powerpc. For the ulps regeneration
I removed the existing clog and clog10 ulps before regenerating to
allow any reduced ulps to appear. Tests added include those found by
random test generation to produce large ulps either before or after
the patch, and some found by trying inputs close to the (0.75, 0.5)
threshold where the potential errors from using log are largest.
[BZ #19016]
* sysdeps/generic/math_private.h (__x2y2m1f): Update comment to
allow more cases with X^2 + Y^2 >= 0.5.
* sysdeps/ieee754/dbl-64/x2y2m1.c (__x2y2m1): Likewise. Add -1 as
normal element in sum instead of special-casing based on values of
arguments.
* sysdeps/ieee754/dbl-64/x2y2m1f.c (__x2y2m1f): Update comment.
* sysdeps/ieee754/ldbl-128/x2y2m1l.c (__x2y2m1l): Likewise. Add
-1 as normal element in sum instead of special-casing based on
values of arguments.
* sysdeps/ieee754/ldbl-128ibm/x2y2m1l.c (__x2y2m1l): Likewise.
* sysdeps/ieee754/ldbl-96/x2y2m1.c [FLT_EVAL_METHOD != 0]
(__x2y2m1): Update comment.
* sysdeps/ieee754/ldbl-96/x2y2m1l.c (__x2y2m1l): Likewise. Add -1
as normal element in sum instead of special-casing based on values
of arguments.
* math/s_clog.c (__clog): Handle more cases using log1p without
hypot.
* math/s_clog10.c (__clog10): Likewise.
* math/s_clog10f.c (__clog10f): Likewise.
* math/s_clog10l.c (__clog10l): Likewise.
* math/s_clogf.c (__clogf): Likewise.
* math/s_clogl.c (__clogl): Likewise.
* math/auto-libm-test-in: Add more tests of clog and clog10.
* math/auto-libm-test-out: Regenerated.
* sysdeps/i386/fpu/libm-test-ulps: Update.
* sysdeps/x86_64/fpu/libm-test-ulps: Likewise.
The flt-32 version of powf can be inaccurate because of bugs in the
extra-precision calculation of (x-1)/(x+1) or (x-1.5)/(x+1.5) as part
of calculating log(x) with extra precision: a constant used (as part
of adding 1 or 1.5 through integer arithmetic) is incorrect, and then
the code fails to mask a computed high part before using it in
arithmetic that relies on s_h*t_h being exactly representable. This
patch fixes these bugs.
Tested for x86_64 and x86. x86_64 ulps for powf removed and
regenerated to reflect reduced ulps from the increased accuracy for
existing tests.
[BZ #18956]
* sysdeps/ieee754/flt-32/e_powf.c (__ieee754_powf): Add 0x00400000
not 0x0040000 for high bit of mantissa. Mask with 0xfffff000 when
extracting high part.
* math/auto-libm-test-in: Add another test of pow.
* math/auto-libm-test-out: Regenerated.
* sysdeps/x86_64/fpu/libm-test-ulps: Update.
Similar to various other bugs in this area, pow functions can fail to
raise the underflow exception when the result is tiny and inexact but
one or more low bits of the intermediate result that is scaled down
(or, in the i386 case, converted from a wider evaluation format) are
zero. This patch forces the exception in a similar way to previous
fixes, thereby concluding the fixes for known bugs with missing
underflow exceptions currently filed in Bugzilla.
Tested for x86_64, x86, mips64 and powerpc.
[BZ #18825]
* sysdeps/i386/fpu/i386-math-asm.h (FLT_NARROW_EVAL_UFLOW_NONNAN):
New macro.
(DBL_NARROW_EVAL_UFLOW_NONNAN): Likewise.
(LDBL_CHECK_FORCE_UFLOW_NONNAN): Likewise.
* sysdeps/i386/fpu/e_pow.S: Use DEFINE_DBL_MIN.
(__ieee754_pow): Use DBL_NARROW_EVAL_UFLOW_NONNAN instead of
DBL_NARROW_EVAL, reloading the PIC register as needed.
* sysdeps/i386/fpu/e_powf.S: Use DEFINE_FLT_MIN.
(__ieee754_powf): Use FLT_NARROW_EVAL_UFLOW_NONNAN instead of
FLT_NARROW_EVAL. Use separate return path for case when first
argument is NaN.
* sysdeps/i386/fpu/e_powl.S: Include <i386-math-asm.h>. Use
DEFINE_LDBL_MIN.
(__ieee754_powl): Use LDBL_CHECK_FORCE_UFLOW_NONNAN, reloading the
PIC register.
* sysdeps/ieee754/dbl-64/e_pow.c (__ieee754_pow): Use
math_check_force_underflow_nonneg.
* sysdeps/ieee754/flt-32/e_powf.c (__ieee754_powf): Force
underflow for subnormal result.
* sysdeps/ieee754/ldbl-128/e_powl.c (__ieee754_powl): Likewise.
* sysdeps/ieee754/ldbl-128ibm/e_powl.c (__ieee754_powl): Use
math_check_force_underflow_nonneg.
* sysdeps/x86/fpu/powl_helper.c (__powl_helper): Use
math_check_force_underflow.
* sysdeps/x86_64/fpu/x86_64-math-asm.h
(LDBL_CHECK_FORCE_UFLOW_NONNAN): New macro.
* sysdeps/x86_64/fpu/e_powl.S: Include <x86_64-math-asm.h>. Use
DEFINE_LDBL_MIN.
(__ieee754_powl): Use LDBL_CHECK_FORCE_UFLOW_NONNAN.
* math/auto-libm-test-in: Add more tests of pow.
* math/auto-libm-test-out: Regenerated.
Fix a regression introduced with commit 0d23a5c1 [Static dlopen
correction fallout fixes] that caused the default library search path to
be ignored for modules loaded with dlopen from static executables.
[BZ #17250]
* elf/dl-support.c (_dl_main_map): Don't initialize l_flags_1
member.
Similar to various other bugs in this area, hypot functions can fail
to raise the underflow exception when the result is tiny and inexact
but one or more low bits of the intermediate result that is scaled
down (or, in the i386 case, converted from a wider evaluation format)
are zero. This patch forces the exception in a similar way to
previous fixes.
Note that this issue cannot arise for implementations of hypotf using
double (or wider) for intermediate evaluation (if hypotf should
underflow, that means the double square root is being computed of some
number of the form N*2^-298, for 0 < N < 2^46, which is exactly
represented as a double, and whatever the rounding mode such a square
root cannot have a mantissa with all zeroes after the initial 23
bits). Thus no changes are made to hypotf implementations in this
patch, only to hypot and hypotl.
Tested for x86_64, x86, mips64 and powerpc.
[BZ #18803]
* sysdeps/i386/fpu/e_hypot.S: Use DEFINE_DBL_MIN.
(MO): New macro.
(__ieee754_hypot) [PIC]: Load PIC register.
(__ieee754_hypot): Use DBL_NARROW_EVAL_UFLOW_NONNEG instead of
DBL_NARROW_EVAL.
* sysdeps/ieee754/dbl-64/e_hypot.c (__ieee754_hypot): Use
math_check_force_underflow_nonneg in case where result might be
tiny.
* sysdeps/ieee754/ldbl-128/e_hypotl.c (__ieee754_hypotl):
Likewise.
* sysdeps/ieee754/ldbl-128ibm/e_hypotl.c (__ieee754_hypotl):
Likewise.
* sysdeps/ieee754/ldbl-96/e_hypotl.c (__ieee754_hypotl): Likewise.
* sysdeps/powerpc/fpu/e_hypot.c (__ieee754_hypot): Likewise.
* math/auto-libm-test-in: Add more tests of hypot.
* math/auto-libm-test-out: Regenerated.
The x86_64 fma4 version of pow fails to disable contraction of
operations other than those explicitly intended to use fma
instructions, so resulting in large ulps errors on processors with
fma4 instructions, as in bug 18104 (165ulp for the test added for that
bug; error originally reported by "blaaa" on #glibc). This patch adds
$(config-cflags-nofma) for e_pow-fma4.c, corresponding to the use for
e_pow.c in sysdeps/ieee754/dbl-64/Makefile.
Tested for x86_64 on a processor with fma4.
[BZ #19003]
* sysdeps/x86_64/fpu/multiarch/Makefile (CFLAGS-e_pow-fma4.c): Add
$(config-cflags-nofma).
i386 exp, hypot and pow functions can return overflowing and
underflowing values with excess range and precision; ; Wilco
Dijkstra's patches to make isfinite etc. expand inline cause this
pre-existing issue to result in test failures.
This patch fixes those functions to avoid excess range and precision
in their return values. Appropriate macros are added for the repeated
code sequences; in future I'll add more such macros and refactor
existing code forcing underflow (with or without also eliminating
excess range and precision from the return value) to use such macros.
Tested for x86. If, after this patch, you still see x86 libm test
failures with excess range or precision, please file bugs in Bugzilla.
[BZ #18980]
* sysdeps/i386/fpu/i386-math-asm.h (DEFINE_FLT_MIN): New macro.
(DEFINE_DBL_MIN): Likewise.
(FLT_NARROW_EVAL_UFLOW_NONNEG_NAN): Likewise.
(DBL_NARROW_EVAL_UFLOW_NONNEG_NAN): Likewise.
(FLT_NARROW_EVAL_UFLOW_NONNEG): Likewise.
(DBL_NARROW_EVAL_UFLOW_NONNEG): Likewise.
* sysdeps/i386/fpu/e_exp.S: Include <i386-math-asm.h>.
(dbl_min): Replace with use of DEFINE_DBL_MIN.
(__ieee754_exp): Use DBL_NARROW_EVAL_UFLOW_NONNEG_NAN.
(__exp_finite): Use DBL_NARROW_EVAL_UFLOW_NONNEG.
* sysdeps/i386/fpu/e_exp10.S: Include <i386-math-asm.h>.
(dbl_min): Replace with use of DEFINE_DBL_MIN.
(__ieee754_exp10): Use DBL_NARROW_EVAL_UFLOW_NONNEG_NAN.
* sysdeps/i386/fpu/e_exp10f.S: Include <i386-math-asm.h>.
(flt_min): Replace with use of DEFINE_FLT_MIN.
(__ieee754_exp10f): Use FLT_NARROW_EVAL_UFLOW_NONNEG_NAN.
* sysdeps/i386/fpu/e_exp2.S: Include <i386-math-asm.h>.
(dbl_min): Replace with use of DEFINE_DBL_MIN.
(__ieee754_exp2): Use DBL_NARROW_EVAL_UFLOW_NONNEG_NAN.
* sysdeps/i386/fpu/e_exp2f.S: Include <i386-math-asm.h>.
(flt_min): Replace with use of DEFINE_FLT_MIN.
(__ieee754_exp2f): Use FLT_NARROW_EVAL_UFLOW_NONNEG_NAN.
* sysdeps/i386/fpu/e_expf.S: Include <i386-math-asm.h>.
(flt_min): Replace with use of DEFINE_FLT_MIN.
(__ieee754_expf): Use FLT_NARROW_EVAL_UFLOW_NONNEG_NAN.
(__expf_finite): Use FLT_NARROW_EVAL_UFLOW_NONNEG.
* sysdeps/i386/fpu/e_hypot.S: Include <i386-math-asm.h>.
(__ieee754_hypot): Use DBL_NARROW_EVAL.
* sysdeps/i386/fpu/e_hypotf.S: Include <i386-math-asm.h>.
(__ieee754_hypotf): Use FLT_NARROW_EVAL.
* sysdeps/i386/fpu/e_pow.S: Include <i386-math-asm.h>.
(__ieee754_pow): Use DBL_NARROW_EVAL.
* sysdeps/i386/fpu/e_powf.S: Include <i386-math-asm.h>.
(__ieee754_powf): Use FLT_NARROW_EVAL.
* sysdeps/i386/i686/fpu/multiarch/e_expf-sse2.S
(__ieee754_expf_sse2): Convert double-precision result to single
precision.
* sysdeps/i386/fpu/libm-test-ulps: Update.
i386 scalb / scalbn / scalbln (and thus ldexp) functions for float and
double can return results with excess range (and consequently excess
precision for subnormal results). As the results of these functions
are fully determined by reference to IEEE 754 operations, this is
unambiguously a bug, apart from the testsuite failures it causes.
This patch makes those functions store their results on the stack and
load them back to eliminate the excess range. Double rounding is not
a problem, as the only cases where it could occur are when the result
overflows or underflows for extended precision, and then the
double-rounded results are the same as the single-rounded results.
The new macros will be used for more functions, more such macros
added, and existing code refactored to use such macros, in subsequent
patches.
Tested for x86. Committed.
[BZ #18981]
* sysdeps/i386/fpu/i386-math-asm.h: New file.
* sysdeps/i386/fpu/e_scalb.S: Include <i386-math-asm.h>.
(__ieee754_scalb): Use DBL_NARROW_EVAL.
* sysdeps/i386/fpu/e_scalbf.S: Include <i386-math-asm.h>.
(__ieee754_scalbf): Use FLT_NARROW_EVAL.
* sysdeps/i386/fpu/s_scalbn.S: Include <i386-math-asm.h>.
(__scalbn): Use DBL_NARROW_EVAL.
* sysdeps/i386/fpu/s_scalbnf.S: Include <i386-math-asm.h>.
(__scalbnf): Use FLT_NARROW_EVAL.
built-ins when available. Since going through the PLT is expensive for these small functions,
inlining results in major speedups (about 7x on Cortex-A57 for isinf). The GCC built-ins are not
correct if signalling NaN support is required, and thus are turned off in that case (see GCC bug
66462). The test-snan.c tests sNaNs and so must be explicitly built with -fsignaling-nans.
2015-09-18 Wilco Dijkstra <wdijkstr@arm.com>
[BZ #15367]
[BZ #17441]
* math/Makefile: Build test-snan.c with -fsignaling-nans.
* math/math.h (fpclassify): Use __builtin_fpclassify when
available. (signbit): Use __builtin_signbit(f/l).
(isfinite): Use__builtin_isfinite. (isnormal): Use
__builtin_isnormal. (isnan): Use __builtin_isnan.
(isinf): Use __builtin_isinf_sign.
In ISO 8601, +03:30 is a valid time zone. Currently, strptime() only
parses it as a 2-digit time zone an believes this is +03:00. This change
makes it accept a single colon.
C99/C11 Annex G specifies the sign of the zero part of the result of
ctan (x +/- i * Inf) and ctanh (+/-Inf + i * y). This patch fixes glibc
to follow that specification, along the lines I described in my review
of Andreas's previous patch for this issue
<https://sourceware.org/ml/libc-alpha/2014-08/msg00142.html>.
Tested for x86_64.
2015-09-17 Joseph Myers <joseph@codesourcery.com>
Andreas Schwab <schwab@suse.de>
[BZ #17118]
* math/s_ctan.c (__ctan): Determine sign of zero real part of
result when imaginary part of argument is infinite using sine and
cosine.
* math/s_ctanf.c (__ctanf): Likewise.
* math/s_ctanl.c (__ctanl): Likewise.
* math/s_ctanh.c (__ctanh): Determine sign of zero imaginary part
of result when real part of argument is infinite using sine and
cosine.
* math/s_ctanhf.c (__ctanhf): Likewise.
* math/s_ctanhl.c (__ctanhl): Likewise.
* math/libm-test.inc (ctan_test_data): Add more tests of ctan.
(ctanh_test_data): Add more tests of ctanh.
Bug 15384 notes that in __finite, two different constants are used
that could be the same constant (the result only depends on the
exponent of the floating-point representation), and that using the
same constant is better for architectures where constants need loading
from a constant pool. This patch implements that change.
Tested for x86_64, mips64 and powerpc.
[BZ #15384]
* sysdeps/ieee754/dbl-64/s_finite.c (FINITE): Use same constant as
bit-mask as in subtraction.
* sysdeps/ieee754/dbl-64/wordsize-64/s_finite.c (__finite):
Likewise.
* sysdeps/ieee754/flt-32/s_finitef.c (FINITEF): Likewise.
* sysdeps/ieee754/ldbl-128/s_finitel.c (__finitel): Likewise.
* sysdeps/ieee754/ldbl-128ibm/s_finitel.c (__finitel): Likewise.
Similar to various other bugs in this area, tgamma functions can fail
to raise the underflow exception when the result is tiny and inexact
but one or more low bits of the intermediate result that is scaled
down are zero. This patch forces the exception in a similar way to
previous fixes.
Tested for x86_64, x86, mips64 and powerpc.
[BZ #18951]
* sysdeps/ieee754/dbl-64/e_gamma_r.c (__ieee754_gamma_r): Force
underflow exception for small results.
* sysdeps/ieee754/flt-32/e_gammaf_r.c (__ieee754_gammaf_r):
Likewise.
* sysdeps/ieee754/ldbl-128/e_gammal_r.c (__ieee754_gammal_r):
Likewise.
* sysdeps/ieee754/ldbl-128ibm/e_gammal_r.c (__ieee754_gammal_r):
Likewise.
* sysdeps/ieee754/ldbl-96/e_gammal_r.c (__ieee754_gammal_r):
Likewise.
* math/auto-libm-test-in: Add more tests of tgamma.
* math/auto-libm-test-out: Regenerated.
As noted in bug 6803, scalbn fails to set errno on overflow and
underflow. This patch fixes this by making scalbn an alias of ldexp,
which has exactly the same semantics (for floating-point types with
radix 2) and already has wrappers that deal with setting errno,
instead of an alias of the internal __scalbn (which ldexp calls).
Notes:
* Where compat symbols were defined for scalbn functions, I didn't
change what they point to (to keep the patch minimal), so such
compat symbols continue to go directly to the non-errno-setting
functions.
* Mike, I didn't do anything with the IA64 versions of these
functions, where I think both the ldexp and scalbn functions already
deal with setting errno. As a cleanup (not needed to fix this bug)
however you might want to make those functions into aliases for
IA64; there is no need for them to be separate function
implementations at all.
* This concludes the fix for bug 6803 since the scalb and scalbln
cases of that bug were fixed some time ago.
Tested for x86_64, x86, mips64 and powerpc.
[BZ #6803]
* math/s_ldexp.c (scalbn): Define as weak alias of __ldexp.
[NO_LONG_DOUBLE] (scalbnl): Define as weak alias of __ldexp.
* math/s_ldexpf.c (scalbnf): Define as weak alias of __ldexpf.
* math/s_ldexpl.c (scalbnl): Define as weak alias of __ldexpl.
* sysdeps/i386/fpu/s_scalbn.S (scalbn): Remove alias.
* sysdeps/i386/fpu/s_scalbnf.S (scalbnf): Likewise.
* sysdeps/i386/fpu/s_scalbnl.S (scalbnl): Likewise.
* sysdeps/ieee754/dbl-64/s_scalbn.c (scalbn): Likewise.
[NO_LONG_DOUBLE] (scalbnl): Likewise.
* sysdeps/ieee754/dbl-64/wordsize-64/s_scalbn.c (scalbn):
Likewise.
[NO_LONG_DOUBLE] (scalbnl): Likewise.
* sysdeps/ieee754/flt-32/s_scalbnf.c (scalbnf): Likewise.
* sysdeps/ieee754/ldbl-128/s_scalbnl.c (scalbnl): Likewise.
* sysdeps/ieee754/ldbl-128ibm/s_scalbnl.c (scalbnl): Remove
long_double_symbol calls.
* sysdeps/ieee754/ldbl-64-128/s_scalbnl.c (scalbnl): Likewise.
* sysdeps/ieee754/ldbl-opt/s_ldexpl.c (__ldexpl_2): Define as
strong alias of __ldexpl.
(scalbnl): Define using long_double_symbol.
* sysdeps/m68k/m680x0/fpu/s_scalbn.c (__CONCATX(scalbn,suffix)):
Remove alias.
* sysdeps/sparc/sparc64/soft-fp/s_scalbnl.c (scalbnl): Likewise.
* sysdeps/x86_64/fpu/s_scalbnl.S (scalbnl): Likewise.
* math/libm-test.inc (scalbn_test_data): Add errno expectations.
(scalbln_test_data): Add more errno expectations.
The ldbl-128 and ldbl-128ibm expm1l implementations have code to
handle +Inf and finite arguments above an overflow threshold. Since
they now use __expl for large positive arguments to fix other
problems, this code is unreachable; this patch removes it.
Tested for mips64 and powerpc.
[BZ #16415]
* sysdeps/ieee754/ldbl-128/s_expm1l.c (maxlog): Remove variable.
(__expm1l): Remove code to handle positive infinity and overflow.
* sysdeps/ieee754/ldbl-128ibm/s_expm1l.c (maxlog): Remove
variable.
(__expm1l): Remove code to handle positive infinity and overflow.
math.h incorrectly declares various functions for XSI POSIX 2001 and
2008 editions. gamma was removed in the 2001 edition but is still
declared, along with gammaf and gammal which were never standard
functions. isnan is still declared as a function, along with isnanf
and isnanl which were never standard functions, although in 2001 the
function was replaced by the type-generic macro. scalbf and scalbl
are declared although never standard, and scalb was removed in the
2008 edition but is still declared. The scalb type-generic macro in
tgmath.h shouldn't be present for any POSIX version, since POSIX never
had such a type-generic macro.
This patch disables all those declarations in the relevant cases (as a
minimal fix, it leaves them enabled for __USE_MISC). For the matter
of declaring scalb but not scalbf or scalbl for the 2001 edition, a
new macro __MATH_DECLARING_DOUBLE is added, defined by math.h around
includes of bits/mathcalls.h, for bits/mathcalls.h to use to test
which type's functions are being declared.
Tested for x86_64 and x86 (testsuite, and that installed stripped
shared libraries are unchanged by the patch).
[BZ #18967]
* math/math.h (__MATH_DECLARING_DOUBLE): New macro. Define and
undefine around includes of <bits/mathcalls.h>.
* math/bits/mathcalls.h [!__USE_MISC && __USE_XOPEN2K] (isnan): Do
not declare function.
[!__USE_MISC && __USE_XOPEN2K] (gamma): Likewise.
[!__USE_MISC && (!__MATH_DECLARING_DOUBLE || __USE_XOPEN2K8)]
(scalb): Likewise.
* math/tgmath.h [!__USE_MISC && __USE_XOPEN_EXTENDED] (scalb): Do
not define macro.
* conform/Makefile (test-xfail-XOPEN2K/math.h/conform): Remove
variable.
(test-xfail-XOPEN2K/tgmath.h/conform): Likewise.
(test-xfail-XOPEN2K8/math.h/conform): Likewise.
(test-xfail-XOPEN2K8/tgmath.h/conform): Likewise.
The ldbl-128ibm implementation of nearbyintl wrongly uses signaling
comparisons such as "if (fabs (u.d[0].d) < TWO52)" on arguments that
might be NaNs, when "invalid" exceptions should not be raised. (For
hard float, this issue may be hidden by
<https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58684>, powerpc GCC
wrongly only using unordered comparison instructions.) This patch
fixes this by just returning the argument if it is not finite (because
of the arbitrary value of the low part of a NaN in IBM long double,
there are quite a lot of comparisons that could end up involving a NaN
when the argument to nearbyintl is a NaN, so excluding NaN arguments
at the start is the simplest and safest fix).
Tested for powerpc-nofpu, where it removes failures for spurious
"invalid" exceptions from nearbyintl.
[BZ #18857]
* sysdeps/ieee754/ldbl-128ibm/s_nearbyintl.c (__nearbyintl): Just
return non-finite argument without doing ordered comparisons on
it.
Bug 16296 notes that fegetround is a pure function and should be
marked as such in fenv.h. This patch implements that.
Tested for x86_64 and x86 (testsuite, and that installed stripped
shared libraries are unchanged by this patch).
[BZ #16296]
* math/fenv.h (fegetround): Use __attribute_pure__.
* include/fenv.h (__fegetround): Likewise.
Similar to various other bugs in this area, ctan and ctanh can fail to
raise the underflow exception for some cases of results that are tiny
and inexact. This patch forces the exception in a similar way to
previous fixes.
Tested for x86_64 and x86.
[BZ #18595]
* math/s_ctan.c (__ctan): Force underflow exception for results
whose real or imaginary part has small absolute value.
* math/s_ctanf.c (__ctanf): Likewise.
* math/s_ctanh.c (__ctanh): Likewise.
* math/s_ctanhf.c (__ctanhf): Likewise.
* math/s_ctanhl.c (__ctanhl): Likewise.
* math/s_ctanl.c (__ctanl): Likewise.
* math/auto-libm-test-in: Do not allow missing underflow for ctan
and ctanh. Add more tests of ctan and ctanh.
Bug 15918 points out that the handling of infinities in hypotf can be
simplified: it's enough to return the absolute value of the infinite
argument without first comparing it to the other argument and possibly
returning that other argument's absolute value. This patch makes that
cleanup (which should not change how hypotf behaves on any input).
Tested for x86_64.
[BZ #15918]
* sysdeps/ieee754/flt-32/e_hypotf.c (__ieee754_hypotf): Simplify
handling of cases where one argument is an infinity.
On i386, the double version of exp10 can miss underflow exceptions if
the result is in the subnormal range for double but the last 11 bits
of the 64-bit extended-precision mantissa happen to be zero. This
patch forces the exception in a similar way to previous fixes.
As with the exp2 and exp fixes, the exp10f changes may in fact not be
needed to ensure underflow exceptions, but are included for
consistency and to fix the exp10 part of bug 18875 by ensuring that
excess range and precision is removed from underflowing return values.
Tested for x86_64 and x86.
[BZ #18875]
[BZ #18966]
* sysdeps/i386/fpu/e_exp10.S (dbl_min): New object.
(MO): New macro.
(__ieee754_exp10): For small results, force underflow exception
and remove excess range and precision from return value.
* sysdeps/i386/fpu/e_exp10f.S (flt_min): New object.
(MO): New macro.
(__ieee754_exp10f): For small results, force underflow exception
and remove excess range and precision from return value.
* math/auto-libm-test-in: Add more tests of exp10.
* math/auto-libm-test-out: Regenerated.
On i386, the double version of exp can miss underflow exceptions if
the result is in the subnormal range for double but the last 11 bits
of the 64-bit extended-precision mantissa happen to be zero. This
patch forces the exception in a similar way to previous fixes.
As with the exp2 fixes, the expf changes may in fact not be needed to
ensure underflow exceptions, but are included for consistency and to
fix the exp part of bug 18875 by ensuring that excess range and
precision is removed from underflowing return values.
Tested for x86_64 and x86.
[BZ #18875]
[BZ #18961]
* sysdeps/i386/fpu/e_exp.S (dbl_min): New object.
(MO): New macro.
(__ieee754_exp): For small results, force underflow exception and
remove excess range and precision from return value.
(__exp_finite): Likewise.
* sysdeps/i386/fpu/e_expf.S (flt_min): New object.
(MO): New macro.
(__ieee754_expf): For small results, force underflow exception and
remove excess range and precision from return value.
(__expf_finite): Likewise.
* math/auto-libm-test-in: Add more tests of exp.
* math/auto-libm-test-out: Regenerated.
Various exp2 implementations in glibc can miss underflow exceptions
when the scaling down part of the calculation is exact (or, in the x86
case, when the conversion from extended precision to the target
precision is exact). This patch forces the exception in a similar way
to previous fixes.
The x86 exp2f changes may in fact not be needed for this purpose -
it's likely to be the case that no argument of type float has an exp2
result so close to an exact subnormal float value that it equals that
value when rounded to 64 bits (even taking account of variation
between different x86 implementations). However, they are included
for consistency with the changes to exp2 and so as to fix the exp2f
part of bug 18875 by ensuring that excess range and precision is
removed from underflowing return values.
Tested for x86_64, x86 and mips64.
[BZ #16521]
[BZ #18875]
* math/e_exp2l.c (__ieee754_exp2l): Force underflow exception for
small results.
* sysdeps/i386/fpu/e_exp2.S (dbl_min): New object.
(MO): New macro.
(__ieee754_exp2): For small results, force underflow exception and
remove excess range and precision from return value.
* sysdeps/i386/fpu/e_exp2f.S (flt_min): New object.
(MO): New macro.
(__ieee754_exp2f): For small results, force underflow exception
and remove excess range and precision from return value.
* sysdeps/i386/fpu/e_exp2l.S (ldbl_min): New object.
(MO): New macro.
(__ieee754_exp2l): Force underflow exception for small results.
* sysdeps/ieee754/dbl-64/e_exp2.c (__ieee754_exp2): Likewise.
* sysdeps/ieee754/flt-32/e_exp2f.c (__ieee754_exp2f): Likewise.
* sysdeps/x86_64/fpu/e_exp2l.S (ldbl_min): New object.
(MO): New macro.
(__ieee754_exp2l): Force underflow exception for small results.
* math/auto-libm-test-in: Add more tests or exp2.
* math/auto-libm-test-out: Regenerated.
If you pass in a path that fails to be opened, then output_path is set to
NULL, and an error is flagged. Then at the end, we use both of those:
cannot write output files to `(null)': No such file or directory
Tweak the message to use the user's input when output_path is NULL.
It was noted in
<https://sourceware.org/ml/libc-alpha/2012-09/msg00305.html> that the
bits/*.h naming scheme should only be used for installed headers.
This patch renames bits/atomic.h to atomic-machine.h to follow that
convention.
This is the only change in this series that needs to change the
filename rather than simply removing a directory level (because both
atomic.h and bits/atomic.h exist at present).
Tested for x86_64 (testsuite, and that installed stripped shared
libraries are unchanged by the patch).
[BZ #14912]
* sysdeps/aarch64/bits/atomic.h: Move to ...
* sysdeps/aarch64/atomic-machine.h: ...here.
(_AARCH64_BITS_ATOMIC_H): Rename macro to
_AARCH64_ATOMIC_MACHINE_H.
* sysdeps/alpha/bits/atomic.h: Move to ...
* sysdeps/alpha/atomic-machine.h: ...here.
* sysdeps/arm/bits/atomic.h: Move to ...
* sysdeps/arm/atomic-machine.h: ...here. Update comments.
* bits/atomic.h: Move to ...
* sysdeps/generic/atomic-machine.h: ...here.
(_BITS_ATOMIC_H): Rename macro to _ATOMIC_MACHINE_H.
* sysdeps/i386/bits/atomic.h: Move to ...
* sysdeps/i386/atomic-machine.h: ...here.
* sysdeps/ia64/bits/atomic.h: Move to ...
* sysdeps/ia64/atomic-machine.h: ...here.
* sysdeps/m68k/coldfire/bits/atomic.h: Move to ...
* sysdeps/m68k/coldfire/atomic-machine.h: ...here.
(_BITS_ATOMIC_H): Rename macro to _ATOMIC_MACHINE_H.
* sysdeps/m68k/m680x0/m68020/bits/atomic.h: Move to ...
* sysdeps/m68k/m680x0/m68020/atomic-machine.h: ...here.
* sysdeps/microblaze/bits/atomic.h: Move to ...
* sysdeps/microblaze/atomic-machine.h: ...here.
* sysdeps/mips/bits/atomic.h: Move to ...
* sysdeps/mips/atomic-machine.h: ...here.
(_MIPS_BITS_ATOMIC_H): Rename macro to _MIPS_ATOMIC_MACHINE_H.
* sysdeps/powerpc/bits/atomic.h: Move to ...
* sysdeps/powerpc/atomic-machine.h: ...here. Update comments.
* sysdeps/powerpc/powerpc32/bits/atomic.h: Move to ...
* sysdeps/powerpc/powerpc32/atomic-machine.h: ...here. Update
comments. Include <atomic-machine.h> instead of <bits/atomic.h>.
* sysdeps/powerpc/powerpc64/bits/atomic.h: Move to ...
* sysdeps/powerpc/powerpc64/atomic-machine.h: ...here. Include
<atomic-machine.h> instead of <bits/atomic.h>.
* sysdeps/s390/bits/atomic.h: Move to ...
* sysdeps/s390/atomic-machine.h: ...here.
* sysdeps/sparc/sparc32/bits/atomic.h: Move to ...
* sysdeps/sparc/sparc32/atomic-machine.h: ...here.
(_BITS_ATOMIC_H): Rename macro to _ATOMIC_MACHINE_H.
* sysdeps/sparc/sparc32/sparcv9/bits/atomic.h: Move to ...
* sysdeps/sparc/sparc32/sparcv9/atomic-machine.h: ...here.
* sysdeps/sparc/sparc64/bits/atomic.h: Move to ...
* sysdeps/sparc/sparc64/atomic-machine.h: ...here.
* sysdeps/tile/bits/atomic.h: Move to ...
* sysdeps/tile/atomic-machine.h: ...here.
* sysdeps/tile/tilegx/bits/atomic.h: Move to ...
* sysdeps/tile/tilegx/atomic-machine.h: ...here. Include
<sysdeps/tile/atomic-machine.h> instead of
<sysdeps/tile/bits/atomic.h>.
(_BITS_ATOMIC_H): Rename macro to _ATOMIC_MACHINE_H.
* sysdeps/tile/tilepro/bits/atomic.h: Move to ...
* sysdeps/tile/tilepro/atomic-machine.h: ...here. Include
<sysdeps/tile/atomic-machine.h> instead of
<sysdeps/tile/bits/atomic.h>.
(_BITS_ATOMIC_H): Rename macro to _ATOMIC_MACHINE_H.
* sysdeps/unix/sysv/linux/arm/bits/atomic.h: Move to ...
* sysdeps/unix/sysv/linux/arm/atomic-machine.h: ...here. Include
<sysdeps/arm/atomic-machine.h> instead of
<sysdeps/arm/bits/atomic.h>.
* sysdeps/unix/sysv/linux/hppa/bits/atomic.h: Move to ...
* sysdeps/unix/sysv/linux/hppa/atomic-machine.h: ...here.
(_BITS_ATOMIC_H): Rename macro to _ATOMIC_MACHINE_H.
* sysdeps/unix/sysv/linux/m68k/coldfire/bits/atomic.h: Move to ...
* sysdeps/unix/sysv/linux/m68k/coldfire/atomic-machine.h: ...here.
(_BITS_ATOMIC_H): Rename macro to _ATOMIC_MACHINE_H.
* sysdeps/unix/sysv/linux/nios2/bits/atomic.h: Move to ...
* sysdeps/unix/sysv/linux/nios2/atomic-machine.h: ...here.
(_NIOS2_BITS_ATOMIC_H): Rename macro to _NIOS2_ATOMIC_MACHINE_H.
* sysdeps/unix/sysv/linux/sh/bits/atomic.h: Move to ...
* sysdeps/unix/sysv/linux/sh/atomic-machine.h: ...here.
* sysdeps/x86_64/bits/atomic.h: Move to ...
* sysdeps/x86_64/atomic-machine.h: ...here.
* include/atomic.h: Include <atomic-machine.h> instead of
<bits/atomic.h>.
The ldbl-128 / ldbl-128ibm implementation of lgammal converts (the
floor of minus) non-integer negative arguments to int to determine the
value of signgam. When those values are outside the range of int,
this produces spurious "invalid" exceptions and incorrect values of
signgam. This patch fixes this by instead determining signgam through
comparing half the integer in question to floor of half the integer.
Tested for mips64, x86_64 and x86.
[BZ #18952]
* sysdeps/ieee754/ldbl-128/e_lgammal_r.c (__ieee754_lgammal_r): Do
not convert non-integer negative arguments to int to determine the
value of signgam.
* math/auto-libm-test-in: Add more tests of lgamma.
* math/auto-libm-test-out: Regenerated.
The existing implementations of lgamma functions (except for the ia64
versions) use the reflection formula for negative arguments. This
suffers large inaccuracy from cancellation near zeros of lgamma (near
where the gamma function is +/- 1).
This patch fixes this inaccuracy. For arguments above -2, there are
no zeros and no large cancellation, while for sufficiently large
negative arguments the zeros are so close to integers that even for
integers +/- 1ulp the log(gamma(1-x)) term dominates and cancellation
is not significant. Thus, it is only necessary to take special care
about cancellation for arguments around a limited number of zeros.
Accordingly, this patch uses precomputed tables of relevant zeros,
expressed as the sum of two floating-point values. The log of the
ratio of two sines can be computed accurately using log1p in cases
where log would lose accuracy. The log of the ratio of two gamma(1-x)
values can be computed using Stirling's approximation (the difference
between two values of that approximation to lgamma being computable
without computing the two values and then subtracting), with
appropriate adjustments (which don't reduce accuracy too much) in
cases where 1-x is too small to use Stirling's approximation directly.
In the interval from -3 to -2, using the ratios of sines and of
gamma(1-x) can still produce too much cancellation between those two
parts of the computation (and that interval is also the worst interval
for computing the ratio between gamma(1-x) values, which computation
becomes more accurate, while being less critical for the final result,
for larger 1-x). Because this can result in errors slightly above
those accepted in glibc, this interval is instead dealt with by
polynomial approximations. Separate polynomial approximations to
(|gamma(x)|-1)(x-n)/(x-x0) are used for each interval of length 1/8
from -3 to -2, where n (-3 or -2) is the nearest integer to the
1/8-interval and x0 is the zero of lgamma in the relevant half-integer
interval (-3 to -2.5 or -2.5 to -2).
Together, the two approaches are intended to give sufficient accuracy
for all negative arguments in the problem range. Outside that range,
the previous implementation continues to be used.
Tested for x86_64, x86, mips64 and powerpc. The mips64 and powerpc
testing shows up pre-existing problems for ldbl-128 and ldbl-128ibm
with large negative arguments giving spurious "invalid" exceptions
(exposed by newly added tests for cases this patch doesn't affect the
logic for); I'll address those problems separately.
[BZ #2542]
[BZ #2543]
[BZ #2558]
* sysdeps/ieee754/dbl-64/e_lgamma_r.c (__ieee754_lgamma_r): Call
__lgamma_neg for arguments from -28.0 to -2.0.
* sysdeps/ieee754/flt-32/e_lgammaf_r.c (__ieee754_lgammaf_r): Call
__lgamma_negf for arguments from -15.0 to -2.0.
* sysdeps/ieee754/ldbl-128/e_lgammal_r.c (__ieee754_lgammal_r):
Call __lgamma_negl for arguments from -48.0 or -50.0 to -2.0.
* sysdeps/ieee754/ldbl-96/e_lgammal_r.c (__ieee754_lgammal_r):
Call __lgamma_negl for arguments from -33.0 to -2.0.
* sysdeps/ieee754/dbl-64/lgamma_neg.c: New file.
* sysdeps/ieee754/dbl-64/lgamma_product.c: Likewise.
* sysdeps/ieee754/flt-32/lgamma_negf.c: Likewise.
* sysdeps/ieee754/flt-32/lgamma_productf.c: Likewise.
* sysdeps/ieee754/ldbl-128/lgamma_negl.c: Likewise.
* sysdeps/ieee754/ldbl-128/lgamma_productl.c: Likewise.
* sysdeps/ieee754/ldbl-128ibm/lgamma_negl.c: Likewise.
* sysdeps/ieee754/ldbl-128ibm/lgamma_productl.c: Likewise.
* sysdeps/ieee754/ldbl-96/lgamma_negl.c: Likewise.
* sysdeps/ieee754/ldbl-96/lgamma_product.c: Likewise.
* sysdeps/ieee754/ldbl-96/lgamma_productl.c: Likewise.
* sysdeps/generic/math_private.h (__lgamma_negf): New prototype.
(__lgamma_neg): Likewise.
(__lgamma_negl): Likewise.
(__lgamma_product): Likewise.
(__lgamma_productl): Likewise.
* math/Makefile (libm-calls): Add lgamma_neg and lgamma_product.
* math/auto-libm-test-in: Add more tests of lgamma.
* math/auto-libm-test-out: Regenerated.
* sysdeps/i386/fpu/libm-test-ulps: Update.
* sysdeps/x86_64/fpu/libm-test-ulps: Likewise.
Topic: strptime supports a %z input field descriptor, which parses a
time zone offset from UTC time into the broken-out time field tm_gmtoff.
Problems:
1) In the current implementation, the minutes portion calculation is
correct only for minutes evenly divisible by 3. This is because the
minutes value is converted to decimal time, but inadequate precision
leads to rounding which calculates results that are too low for
some values.
For example, due to rounding, a +1159 offset string results in an
incorrect tm_gmtoff of 43128 (== 11 * 3600 + 58.8 * 60) seconds,
instead of 43140 (== 11 * 3600 + 59 * 60) seconds. In contrast,
a +1157 offset (minutes divisible by 3) does not cause the bug,
and results in a correct tm_gmtoff of 43020.
2) strptime's %z specifier will not parse time offsets less than
-1200 or greater than +1200, or if only hour digits are present, less
than -12 or greater than +12. It will return NULL for offsets outside
that range. These limits do not meet historical and modern use cases:
* Present day exceeds the +1200 limit:
- Pacific/Auckland (New Zealand) summer time is +1300.
- Pacific/Kiritimati (Christmas Island) is +1400.
- Pacific/Apia (Samoa) summer time is +1400.
* Historical offsets exceeded +1500/-1500.
* POSIX supports -2459 to +2559.
* Offsets up to +/-9959 may occasionally be useful.
* Paul Eggert's notes provide additional detail:
- https://sourceware.org/ml/libc-alpha/2014-12/msg00068.html
- https://sourceware.org/ml/libc-alpha/2014-12/msg00072.html
3) tst-strptime2, part of the 'make check' test suite, does not test
for the above problems.
Corrective actions:
1) In time/strptime_l.c, calculate the offset from the hour and
minute portions directly, without the rounding errors introduced by
decimal time.
2) Remove the +/-1200 range limit, permitting strptime to parse offsets
from -9959 through +9959.
3) Add zone offset values to time/tst-strptime2.c.
* Test minutes evenly divisible by three (+1157) and not evenly
divisible by three (+1158 and +1159).
* Test offsets near the old and new range limits (-1201, -1330, -2459,
-2500, -99, -9959, +1201, +1330, +1400, +1401, +2559, +2600, +99,
and +9959)
The revised strptime passes all old and new tst-strptime2 tests.
This patch fixes the default wordsize-32 mmap implementation offset
calculation for negative values. Current code uses signed shift
operation to calculate the multiple size to use with syscall and
it is implementation defined. Change it to use a division base
on mmap page size (default being as before, 4096).
Tested on armv7hf.
[BZ #18877]
* posix/Makefile (tests): Add tst-mmap-offset.
* posix/tst-mmap.c: New file.
* sysdeps/unix/sysv/linux/generic/wordsize-32/mmap.c (__mmap): Fix
offset calculation for negative values.
This patch set introduces optimized string, wcsmbs and memory functions for
S390/S390x. The functions are accelerated by the usage of the new z13 vector
instructions.
The Principles of Operations manual for IBM z13 is publically available:
http://publibfi.boulder.ibm.com/epubs/pdf/dz9zr010.pdf
The support for these instructions in assembler was introduced by commits:
-"[Committed] S/390: Add support for IBM z13."
(https://sourceware.org/ml/binutils/2015-01/msg00197.html)
-"[Committed] S/390: Add more IBM z13 instructions"
(https://sourceware.org/ml/binutils/2015-03/msg00088.html)
The first patches do preparation for the latter optimization patches.
The floating point exception handling - fetestexcept(), ... - is fixed and
the platform and hwcap strings are extended.
The current ifunc routines memset, memcpy and memcmp are refactored and the
ifunc test-framework is now enabled.
A S390 specific configure-check tests if the used binutils supports the new
vector instructions. The optimized functions are provided via ifunc if the
binutils supports the vector instructions. Otherwise a message is dumped to
configure output and only the currently used common code functions are
available.
The optimized functions are implemented in common for s390-32 and s390-64
and the few differences are handled via #ifdef.
The ifunc-resolvers are defined in files sysdeps/s390/multiarch/<func>.c,
which choose either the current implementation __<func>_c() or the vector
implementation __<func>_vx() depending on the HWCAP_S390_VX flag bit in
AT_HWCAP field. If the bit is set, the hardware and the kernel are supporting
vector registers and instructions. If the used binutils lacks vector-support,
then the default implementation in string or wcsmbs directory is included
here instead.
The file sysdeps/s390/multiarch/<func>-c.c includes the current implementation
and defines the function name __<func>_c.
The assembler files sysdeps/s390/multiarch/<func>-vx.S with the vector
instructions are using the directive '.machine "z13"' to allow building glibc
without option '-march=z13'. Additionally the directive '.machinemode
"zarch_nohighgprs"' is needed for the 31bit glibc. This mode does not set the
highgprs flag in ELF header, which would lead to an unloadable libc on a 31bit
kernel.
The most optimized string functions are structured in the same way:
The first 16 bytes of the string is loaded unaligned via vlbb - vector load
to block boundary (e.g. 4k). This instruction loads 16 bytes if possible.
In case of a page cross, it only loads the last bytes of the current page
without a segmentation fault.
Afterwards these first part of string is processed. If e.g. for strlen the end
of string is reached within this first part, the function returns. Otherwise
the pointer is aligned to 16 byte, so i can load a full vector register with vl
without checking for a page cross. Afterwards the first part of string is
processed. If e.g. for strlen the end of string is reached within this first
part, the function returns. Otherwise the pointer is aligned to 16 byte, so
a full vector register can be loaded with vl - vector load - without checking
for a page cross. The remaining string is processed in a four times unrolled
loop, because benchmark results measured improvements compared to a non
unrolled loop.
The optimized wide string functions can only handle 4byte aligned string
pointers. Although a wchar_t pointer should always be 4byte aligned, the most
current common code wide string functions can handle non aligned strings.
Thus the optimized functions will fall back to the common code functions in
case of a non aligned wide string to behave the same as before this patch.
Some string tests can test the string and the wide string version of a function.
The remaining ones are extended and new wide string tests are added.
This is the same in case of the benchtests.
ChangeLog:
* NEWS: New item for IBM z13 string optimizations.
