Commit Graph

452 Commits

Author SHA1 Message Date
Florian Weimer
9abdae94c7 login: structs utmp, utmpx, lastlog _TIME_BITS independence (bug 30701)
These structs describe file formats under /var/log, and should not
depend on the definition of _TIME_BITS.  This is achieved by
defining __WORDSIZE_TIME64_COMPAT32 to 1 on 32-bit ports that
support 32-bit time_t values (where __time_t is 32 bits).

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2024-04-19 14:38:17 +02:00
Joseph Myers
42cc619dfb Refer to C23 in place of C2X in glibc
WG14 decided to use the name C23 as the informal name of the next
revision of the C standard (notwithstanding the publication date in
2024).  Update references to C2X in glibc to use the C23 name.

This is intended to update everything *except* where it involves
renaming files (the changes involving renaming tests are intended to
be done separately).  In the case of the _ISOC2X_SOURCE feature test
macro - the only user-visible interface involved - support for that
macro is kept for backwards compatibility, while adding
_ISOC23_SOURCE.

Tested for x86_64.
2024-02-01 11:02:01 +00:00
Joseph Myers
b34b46b880 Implement C23 <stdbit.h>
C23 adds a header <stdbit.h> with various functions and type-generic
macros for bit-manipulation of unsigned integers (plus macro defines
related to endianness).  Implement this header for glibc.

The functions have both inline definitions in the header (referenced
by macros defined in the header) and copies with external linkage in
the library (which are implemented in terms of those macros to avoid
duplication).  They are documented in the glibc manual.  Tests, as
well as verifying results for various inputs (of both the macros and
the out-of-line functions), verify the types of those results (which
showed up a bug in an earlier version with the type-generic macro
stdc_has_single_bit wrongly returning a promoted type), that the
macros can be used at top level in a source file (so don't use ({})),
that they evaluate their arguments exactly once, and that the macros
for the type-specific functions have the expected implicit conversions
to the relevant argument type.

Jakub previously referred to -Wconversion warnings in type-generic
macros, so I've included a test with -Wconversion (but the only
warnings I saw and fixed from that test were actually in inline
functions in the <stdbit.h> header - not anything coming from use of
the type-generic macros themselves).

This implementation of the type-generic macros does not handle
unsigned __int128, or unsigned _BitInt types with a width other than
that of a standard integer type (and C23 doesn't require the header to
handle such types either).  Support for those types, using the new
type-generic built-in functions Jakub's added for GCC 14, can
reasonably be added in a followup (along of course with associated
tests).

This implementation doesn't do anything special to handle C++, or have
any tests of functionality in C++ beyond the existing tests that all
headers can be compiled in C++ code; it's not clear exactly what form
this header should take in C++, but probably not one using macros.

DIS ballot comment AT-107 asks for the word "count" to be added to the
names of the stdc_leading_zeros, stdc_leading_ones,
stdc_trailing_zeros and stdc_trailing_ones functions and macros.  I
don't think it's likely to be accepted (accepting any technical
comments would mean having an FDIS ballot), but if it is accepted at
the WG14 meeting (22-26 January in Strasbourg, starting with DIS
ballot comment handling) then there would still be time to update
glibc for the renaming before the 2.39 release.

The new functions and header are placed in the stdlib/ directory in
glibc, rather than creating a new toplevel stdbit/ or putting them in
string/ alongside ffs.

Tested for x86_64 and x86.
2024-01-03 12:07:14 +00:00
Paul Eggert
dff8da6b3e Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
Adhemerval Zanella Netto
ce2bfb8569 linux: Add posix_spawnattr_{get, set}cgroup_np (BZ 26371)
These functions allow to posix_spawn and posix_spawnp to use
CLONE_INTO_CGROUP with clone3, allowing the child process to
be created in a different cgroup version 2.  These are GNU
extensions that are available only for Linux, and also only
for the architectures that implement clone3 wrapper
(HAVE_CLONE3_WRAPPER).

To create a process on a different cgroupv2, one can use the:

  posix_spawnattr_t attr;
  posix_spawnattr_init (&attr);
  posix_spawnattr_setflags (&attr, POSIX_SPAWN_SETCGROUP);
  posix_spawnattr_setcgroup_np (&attr, cgroup);
  posix_spawn (...)

Similar to other posix_spawn flags, POSIX_SPAWN_SETCGROUP control
whether the cgroup file descriptor will be used or not with
clone3.

There is no fallback if either clone3 does not support the flag
or if the architecture does not provide the clone3 wrapper, in
this case posix_spawn returns EOPNOTSUPP.

Checked on x86_64-linux-gnu.

Reviewed-by: Florian Weimer <fweimer@redhat.com>
2023-09-05 13:08:48 -03:00
Paul Pluzhnikov
7f0d9e61f4 Fix all the remaining misspellings -- BZ 25337 2023-06-02 01:39:48 +00:00
Kito Cheng
a225cb3ee9
Remap __GLIBC_FLT_EVAL_METHOD to 0 if __FLT_EVAL_METHOD__ is -1
__GLIBC_FLT_EVAL_METHOD will effect the definition of float_t and
double_t, currently we'll set __GLIBC_FLT_EVAL_METHOD to 2 when
__FLT_EVAL_METHOD__ is -1, that means we'll define float_t and double_t
to long double.

However some target isn't natively (HW) support long double like AArch64 and
RISC-V, they defined long double as 128-bits IEEE 754 floating point type.

That means setting __GLIBC_FLT_EVAL_METHOD to 2 will cause very inefficient
code gen for those target who didn't provide native support for long
double, and that's violate the spirit float_t and double_t - most efficient
types at least as wide as float and double.

So this patch propose to remap __GLIBC_FLT_EVAL_METHOD to 0 rather than
2 when __FLT_EVAL_METHOD__ is -1, which means we'll use float/double
rather than long double for float_t and double_t.

Note: __FLT_EVAL_METHOD__ == -1 means the precision is indeterminable,
      which means compiler might using indeterminable precision during
      optimization/code gen, clang will set this value to -1 when fast
      math is enabled.

Note: Default definition float_t and double_t in current glibc:
      |  __GLIBC_FLT_EVAL_METHOD | float_t     | double_t
      |               0 or 16    | float       | double
      |               1          | double      | doulbe
      |               2          | long double | long double
      More complete list see math/math.h

Note: RISC-V has defined ISA extension to support 128-bits IEEE 754
      floating point operations, but only rare RISC-V core will implement that.

Related link:

[1] LLVM issue (__FLT_EVAL_METHOD__ is set to -1 with Ofast. #60781):
    https://github.com/llvm/llvm-project/issues/60781
[2] Last version of this patch: https://sourceware.org/pipermail/libc-alpha/2023-February/145622.html

Acked-by: Palmer Dabbelt <palmer@rivosinc.com> # RISC-V
Reviewed-by: Wilco Dijkstra  <Wilco.Dijkstra@arm.com>
Link: https://inbox.sourceware.org/libc-alpha/20230314151948.12892-1-kito.cheng@sifive.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-04-28 07:02:48 -07:00
Samuel Thibault
4738bc2185 [hurd] Add MTU_DISCOVER values 2023-02-15 15:14:06 +01:00
Sergey Bugaev
3e35b824a4 hurd: Fix tcflag_t and speed_t types on 64-bit
These are supposed to stay 32-bit even on 64-bit systems. This matches
BSD and Linux, as well as how these types are already defined in
tioctl.defs

Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
2023-02-12 20:03:18 +01:00
Samuel Thibault
569cfcc6bf hurd: Fix _NOFLSH value
shifting 1 (thus an integer) left 31 bit is undefined behavior. We have to
make it an unsigned integer to properly get 0x80000000 (like done in other
places).
2023-01-15 20:56:12 +01:00
Joseph Myers
6d7e8eda9b Update copyright dates with scripts/update-copyrights 2023-01-06 21:14:39 +00:00
Andreas Schwab
954b8f3895 Expose all MAP_ constants in <sys/mman.h> unconditionally (bug 29375)
POSIX reserves the MAP_ prefix for <sys/mman.h>, so there is no need to
conditionalize their definitions on feature test macros.
2022-10-10 09:30:24 +02:00
Joseph Myers
3e5760fcb4 Update _FloatN header support for C++ in GCC 13
GCC 13 adds support for _FloatN and _FloatNx types in C++, so breaking
the installed glibc headers that assume such support is not present.
GCC mostly works around this with fixincludes, but that doesn't help
for building glibc and its tests (glibc doesn't itself contain C++
code, but there's C++ code built for tests).  Update glibc's
bits/floatn-common.h and bits/floatn.h headers to handle the GCC 13
support directly.

In general the changes match those made by fixincludes, though I think
the ones in sysdeps/powerpc/bits/floatn.h, where the header tests
__LDBL_MANT_DIG__ == 113 or uses #elif, wouldn't match the existing
fixincludes patterns.

Some places involving special C++ handling in relation to _FloatN
support are not changed.  There's no need to change the
__HAVE_FLOATN_NOT_TYPEDEF definition (also in a form that wouldn't be
matched by the fixincludes fixes) because it's only used in relation
to macro definitions using features not supported for C++
(__builtin_types_compatible_p and _Generic).  And there's no need to
change the inline function overloads for issignaling, iszero and
iscanonical in C++ because cases where types have the same format but
are no longer compatible types are handled automatically by the C++
overload resolution rules.

This patch also does not change the overload handling for iseqsig, and
there I think changes *are* needed, beyond those in this patch or made
by fixincludes.  The way that overload is defined, via a template
parameter to a structure type, requires overloads whenever the types
are incompatible, even if they have the same format.  So I think we
need to add overloads with GCC 13 for every supported _FloatN and
_FloatNx type, rather than just having one for _Float128 when it has a
different ABI to long double as at present (but for older GCC, such
overloads must not be defined for types that end up defined as
typedefs for another type).

Tested with build-many-glibcs.py: compilers build for
aarch64-linux-gnu ia64-linux-gnu mips64-linux-gnu powerpc-linux-gnu
powerpc64le-linux-gnu x86_64-linux-gnu; glibcs build for
aarch64-linux-gnu ia64-linux-gnu i686-linux-gnu mips-linux-gnu
mips64-linux-gnu-n32 powerpc-linux-gnu powerpc64le-linux-gnu
x86_64-linux-gnu.
2022-09-28 20:10:08 +00:00
Samuel Thibault
af6e07dad7 non-linux: bits/in.h: Add more RFC options 2022-08-15 11:27:04 +02:00
Arjun Shankar
9c443ac455 socket: Check lengths before advancing pointer in CMSG_NXTHDR
The inline and library functions that the CMSG_NXTHDR macro may expand
to increment the pointer to the header before checking the stride of
the increment against available space.  Since C only allows incrementing
pointers to one past the end of an array, the increment must be done
after a length check.  This commit fixes that and includes a regression
test for CMSG_FIRSTHDR and CMSG_NXTHDR.

The Linux, Hurd, and generic headers are all changed.

Tested on Linux on armv7hl, i686, x86_64, aarch64, ppc64le, and s390x.

[BZ #28846]

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2022-08-02 11:10:25 +02:00
Adhemerval Zanella
d19ee3473d linux: Add process_madvise
It was added on Linux 5.10 (ecb8ac8b1f146915aa6b96449b66dd48984caacc)
with the same functionality as madvise but using a pidfd of the target
process.

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

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2022-06-02 15:43:28 -03:00
Adhemerval Zanella
32612615c5 elf: Issue la_symbind for bind-now (BZ #23734)
The audit symbind callback is not called for binaries built with
-Wl,-z,now or when LD_BIND_NOW=1 is used, nor the PLT tracking callbacks
(plt_enter and plt_exit) since this would change the expected
program semantics (where no PLT is expected) and would have performance
implications (such as for BZ#15533).

LAV_CURRENT is also bumped to indicate the audit ABI change (where
la_symbind flags are set by the loader to indicate no possible PLT
trace).

To handle powerpc64 ELFv1 function descriptor, _dl_audit_symbind
requires to know whether bind-now is used so the symbol value is
updated to function text segment instead of the OPD (for lazy binding
this is done by PPC64_LOAD_FUNCPTR on _dl_runtime_resolve).

Checked on x86_64-linux-gnu, i686-linux-gnu, aarch64-linux-gnu,
powerpc64-linux-gnu.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2022-02-01 14:49:46 -03:00
Paul Eggert
581c785bf3 Update copyright dates with scripts/update-copyrights
I used these shell commands:

../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright
(cd ../glibc && git commit -am"[this commit message]")

and then ignored the output, which consisted lines saying "FOO: warning:
copyright statement not found" for each of 7061 files FOO.

I then removed trailing white space from math/tgmath.h,
support/tst-support-open-dev-null-range.c, and
sysdeps/x86_64/multiarch/strlen-vec.S, to work around the following
obscure pre-commit check failure diagnostics from Savannah.  I don't
know why I run into these diagnostics whereas others evidently do not.

remote: *** 912-#endif
remote: *** 913:
remote: *** 914-
remote: *** error: lines with trailing whitespace found
...
remote: *** error: sysdeps/unix/sysv/linux/statx_cp.c: trailing lines
2022-01-01 11:40:24 -08:00
Sunil K Pandey
c21c7bc24e x86-64: Add vector tan/tanf implementation to libmvec
Implement vectorized tan/tanf containing SSE, AVX, AVX2 and
AVX512 versions for libmvec as per vector ABI.  It also contains
accuracy and ABI tests for vector tan/tanf with regenerated ulps.

Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
2021-12-30 10:19:13 -08:00
Sunil K Pandey
8881cca8fb x86-64: Add vector erfc/erfcf implementation to libmvec
Implement vectorized erfc/erfcf containing SSE, AVX, AVX2 and
AVX512 versions for libmvec as per vector ABI.  It also contains
accuracy and ABI tests for vector erfc/erfcf with regenerated ulps.

Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
2021-12-30 10:19:03 -08:00
Sunil K Pandey
e682d01578 x86-64: Add vector asinh/asinhf implementation to libmvec
Implement vectorized asinh/asinhf containing SSE, AVX, AVX2 and
AVX512 versions for libmvec as per vector ABI.  It also contains
accuracy and ABI tests for vector asinh/asinhf with regenerated ulps.

Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
2021-12-29 11:38:56 -08:00
Sunil K Pandey
c0f36fc303 x86-64: Add vector tanh/tanhf implementation to libmvec
Implement vectorized tanh/tanhf containing SSE, AVX, AVX2 and
AVX512 versions for libmvec as per vector ABI.  It also contains
accuracy and ABI tests for vector tanh/tanhf with regenerated ulps.

Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
2021-12-29 11:38:50 -08:00
Sunil K Pandey
f9ce13fdac x86-64: Add vector erf/erff implementation to libmvec
Implement vectorized erf/erff containing SSE, AVX, AVX2 and
AVX512 versions for libmvec as per vector ABI.  It also contains
accuracy and ABI tests for vector erf/erff with regenerated ulps.

Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
2021-12-29 11:38:44 -08:00
Sunil K Pandey
0625489ccc x86-64: Add vector acosh/acoshf implementation to libmvec
Implement vectorized acosh/acoshf containing SSE, AVX, AVX2 and
AVX512 versions for libmvec as per vector ABI.  It also contains
accuracy and ABI tests for vector acosh/acoshf with regenerated ulps.

Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
2021-12-29 11:38:39 -08:00
Sunil K Pandey
6dea4dd3da x86-64: Add vector atanh/atanhf implementation to libmvec
Implement vectorized atanh/atanhf containing SSE, AVX, AVX2 and
AVX512 versions for libmvec as per vector ABI.  It also contains
accuracy and ABI tests for vector atanh/atanhf with regenerated ulps.

Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
2021-12-29 11:38:34 -08:00
Sunil K Pandey
74265c16ab x86-64: Add vector log1p/log1pf implementation to libmvec
Implement vectorized log1p/log1pf containing SSE, AVX, AVX2 and
AVX512 versions for libmvec as per vector ABI.  It also contains
accuracy and ABI tests for vector log1p/log1pf with regenerated ulps.

Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
2021-12-29 11:38:27 -08:00
Sunil K Pandey
7e1722fec8 x86-64: Add vector log2/log2f implementation to libmvec
Implement vectorized log2/log2f containing SSE, AVX, AVX2 and
AVX512 versions for libmvec as per vector ABI.  It also contains
accuracy and ABI tests for vector log2/log2f with regenerated ulps.

Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
2021-12-29 11:38:21 -08:00
Sunil K Pandey
8f8566026d x86-64: Add vector log10/log10f implementation to libmvec
Implement vectorized log10/log10f containing SSE, AVX, AVX2 and
AVX512 versions for libmvec as per vector ABI.  It also contains
accuracy and ABI tests for vector log10/log10f with regenerated ulps.

Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
2021-12-29 11:38:15 -08:00
Sunil K Pandey
2941a24f8c x86-64: Add vector atan2/atan2f implementation to libmvec
Implement vectorized atan2/atan2f containing SSE, AVX, AVX2 and
AVX512 versions for libmvec as per vector ABI.  It also contains
accuracy and ABI tests for vector atan2/atan2f with regenerated ulps.

Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
2021-12-29 11:38:09 -08:00
Sunil K Pandey
2bf02c5843 x86-64: Add vector cbrt/cbrtf implementation to libmvec
Implement vectorized cbrt/cbrtf containing SSE, AVX, AVX2 and
AVX512 versions for libmvec as per vector ABI.  It also contains
accuracy and ABI tests for vector cbrt/cbrtf with regenerated ulps.

Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
2021-12-29 11:38:02 -08:00
Sunil K Pandey
aa1809a1df x86-64: Add vector sinh/sinhf implementation to libmvec
Implement vectorized sinh/sinhf containing SSE, AVX, AVX2 and
AVX512 versions for libmvec as per vector ABI.  It also contains
accuracy and ABI tests for vector sinh/sinhf with regenerated ulps.

Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
2021-12-29 11:37:55 -08:00
Sunil K Pandey
76ddc74e86 x86-64: Add vector expm1/expm1f implementation to libmvec
Implement vectorized expm1/expm1f containing SSE, AVX, AVX2 and
AVX512 versions for libmvec as per vector ABI.  It also contains
accuracy and ABI tests for vector expm1/expm1f with regenerated ulps.

Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
2021-12-29 11:37:49 -08:00
Sunil K Pandey
ef7ea9c132 x86-64: Add vector cosh/coshf implementation to libmvec
Implement vectorized cosh/coshf containing SSE, AVX, AVX2 and
AVX512 versions for libmvec as per vector ABI.  It also contains
accuracy and ABI tests for vector cosh/coshf with regenerated ulps.

Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
2021-12-29 11:37:42 -08:00
Sunil K Pandey
8b726453d5 x86-64: Add vector exp10/exp10f implementation to libmvec
Implement vectorized exp10/exp10f containing SSE, AVX, AVX2 and
AVX512 versions for libmvec as per vector ABI.  It also contains
accuracy and ABI tests for vector exp10/exp10f with regenerated ulps.

Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
2021-12-29 11:37:35 -08:00
Sunil K Pandey
3fc9ccc20b x86-64: Add vector exp2/exp2f implementation to libmvec
Implement vectorized exp2/exp2f containing SSE, AVX, AVX2 and
AVX512 versions for libmvec as per vector ABI.  It also contains
accuracy and ABI tests for vector exp2/exp2f with regenerated ulps.

Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
2021-12-29 11:37:29 -08:00
Sunil K Pandey
37475ba883 x86-64: Add vector hypot/hypotf implementation to libmvec
Implement vectorized hypot/hypotf containing SSE, AVX, AVX2 and
AVX512 versions for libmvec as per vector ABI.  It also contains
accuracy and ABI tests for vector hypot/hypotf with regenerated ulps.

Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
2021-12-29 11:37:21 -08:00
Sunil K Pandey
11c01de14c x86-64: Add vector asin/asinf implementation to libmvec
Implement vectorized asin/asinf containing SSE, AVX, AVX2 and
AVX512 versions for libmvec as per vector ABI.  It also contains
accuracy and ABI tests for vector asin/asinf with regenerated ulps.

Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
2021-12-29 11:37:03 -08:00
Sunil K Pandey
146310177a x86-64: Add vector atan/atanf implementation to libmvec
Implement vectorized atan/atanf containing SSE, AVX, AVX2 and
AVX512 versions for libmvec as per vector ABI.  It also contains
accuracy and ABI tests for vector atan/atanf with regenerated ulps.

Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
2021-12-29 11:36:46 -08:00
Florian Weimer
5d28a8962d elf: Add _dl_find_object function
It can be used to speed up the libgcc unwinder, and the internal
_dl_find_dso_for_object function (which is used for caller
identification in dlopen and related functions, and in dladdr).

_dl_find_object is in the internal namespace due to bug 28503.
If libgcc switches to _dl_find_object, this namespace issue will
be fixed.  It is located in libc for two reasons: it is necessary
to forward the call to the static libc after static dlopen, and
there is a link ordering issue with -static-libgcc and libgcc_eh.a
because libc.so is not a linker script that includes ld.so in the
glibc build tree (so that GCC's internal -lc after libgcc_eh.a does
not pick up ld.so).

It is necessary to do the i386 customization in the
sysdeps/x86/bits/dl_find_object.h header shared with x86-64 because
otherwise, multilib installations are broken.

The implementation uses software transactional memory, as suggested
by Torvald Riegel.  Two copies of the supporting data structures are
used, also achieving full async-signal-safety.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-12-28 22:52:56 +01:00
Adhemerval Zanella
a4b4131355 Set default __TIMESIZE default to 64
This is expected size for newer ABIs.
2021-12-23 11:41:08 -03:00
Sunil K Pandey
f20f980c71 x86-64: Add vector acos/acosf implementation to libmvec
Implement vectorized acos/acosf containing SSE, AVX, AVX2 and
AVX512 versions for libmvec as per vector ABI.  It also contains
accuracy and ABI tests for vector acos/acosf with regenerated ulps.

Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
2021-12-22 13:03:14 -08:00
Florian Weimer
8bd336a00a nptl: Extract <bits/atomic_wide_counter.h> from pthread_cond_common.c
And make it an installed header.  This addresses a few aliasing
violations (which do not seem to result in miscompilation due to
the use of atomics), and also enables use of wide counters in other
parts of the library.

The debug output in nptl/tst-cond22 has been adjusted to print
the 32-bit values instead because it avoids a big-endian/little-endian
difference.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-11-17 12:20:13 +01:00
Adhemerval Zanella
54816ae98d elf: Move LAV_CURRENT to link_lavcurrent.h
No functional change.
2021-11-15 15:28:17 -03:00
Florian Weimer
32b96d0dec Add missing braces to bsearch inline implementation [BZ #28400]
GCC treats the pragma as a statement, so that the else branch only
consists of the pragma, not the return statement.

Fixes commit a725ff1de9 ("Suppress
-Wcast-qual warnings in bsearch").

Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
2021-09-30 20:40:12 +02:00
Jonathan Wakely
a725ff1de9 Suppress -Wcast-qual warnings in bsearch
The first cast to (void *) is redundant but should be (const void *)
anyway, because that's the type of the lvalue being assigned to.

The second cast is necessary and intentionally not const-correct, so
tell the compiler not to warn about it.

Reviewed-by: Florian Weimer <fweimer@redhat.com>
2021-09-30 12:18:48 +01:00
Joseph Myers
858045ad1c Update floating-point feature test macro handling for C2X
ISO C2X has made some changes to the handling of feature test macros
related to features from the floating-point TSes, and to exactly what
such features are present in what headers, that require corresponding
changes in glibc.

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

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

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

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

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

Tested for x86_64 and x86.
2021-06-01 14:22:06 +00:00
H.J. Lu
6c57d32048 sysconf: Add _SC_MINSIGSTKSZ/_SC_SIGSTKSZ [BZ #20305]
Add _SC_MINSIGSTKSZ for the minimum signal stack size derived from
AT_MINSIGSTKSZ, which is the minimum number of bytes of free stack
space required in order to gurantee successful, non-nested handling
of a single signal whose handler is an empty function, and _SC_SIGSTKSZ
which is the suggested minimum number of bytes of stack space required
for a signal stack.

If AT_MINSIGSTKSZ isn't available, sysconf (_SC_MINSIGSTKSZ) returns
MINSIGSTKSZ.  On Linux/x86 with XSAVE, the signal frame used by kernel
is composed of the following areas and laid out as:

 ------------------------------
 | alignment padding          |
 ------------------------------
 | xsave buffer               |
 ------------------------------
 | fsave header (32-bit only) |
 ------------------------------
 | siginfo + ucontext         |
 ------------------------------

Compute AT_MINSIGSTKSZ value as size of xsave buffer + size of fsave
header (32-bit only) + size of siginfo and ucontext + alignment padding.

If _SC_SIGSTKSZ_SOURCE or _GNU_SOURCE are defined, MINSIGSTKSZ and SIGSTKSZ
are redefined as

/* Default stack size for a signal handler: sysconf (SC_SIGSTKSZ).  */
 # undef SIGSTKSZ
 # define SIGSTKSZ sysconf (_SC_SIGSTKSZ)

/* Minimum stack size for a signal handler: SIGSTKSZ.  */
 # undef MINSIGSTKSZ
 # define MINSIGSTKSZ SIGSTKSZ

Compilation will fail if the source assumes constant MINSIGSTKSZ or
SIGSTKSZ.

The reason for not simply increasing the kernel's MINSIGSTKSZ #define
(apart from the fact that it is rarely used, due to glibc's shadowing
definitions) was that userspace binaries will have baked in the old
value of the constant and may be making assumptions about it.

For example, the type (char [MINSIGSTKSZ]) changes if this #define
changes.  This could be a problem if an newly built library tries to
memcpy() or dump such an object defined by and old binary.
Bounds-checking and the stack sizes passed to things like sigaltstack()
and makecontext() could similarly go wrong.
2021-02-01 11:00:52 -08:00
Paul Eggert
2b778ceb40 Update copyright dates with scripts/update-copyrights
I used these shell commands:

../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright
(cd ../glibc && git commit -am"[this commit message]")

and then ignored the output, which consisted lines saying "FOO: warning:
copyright statement not found" for each of 6694 files FOO.
I then removed trailing white space from benchtests/bench-pthread-locks.c
and iconvdata/tst-iconv-big5-hkscs-to-2ucs4.c, to work around this
diagnostic from Savannah:
remote: *** pre-commit check failed ...
remote: *** error: lines with trailing whitespace found
remote: error: hook declined to update refs/heads/master
2021-01-02 12:17:34 -08:00
Samuel Thibault
f6abd97028 hurd: Add WSTOPPED/WCONTINUED/WEXITED/WNOWAIT support [BZ #23091]
The new __proc_waitid RPC now expects WEXITED to be passed, allowing to
properly implement waitid, and thus define the missing W* macros
(according to FreeBSD values).
2020-12-28 23:37:04 +01:00
Jeremie Koenig
d865ff74ba hurd: implement SA_SIGINFO signal handlers.
SA_SIGINFO is actually just another way of expressing what we were
already passing over with struct sigcontext. This just introduces the
SIGINFO interface and fixes the posix values when that interface is
requested by the application.
2020-12-21 01:44:20 +01:00