This matches kernel behavior. With this change, it is possible
to use utimensat as a replacement for the futimens interface,
similar to what glibc does internally.
Reviewed-by: Paul Eggert <eggert@cs.ucla.edu>
This padding is difficult to use for preserving the internal
GLIBC_PRIVATE ABI. The comment is misleading. Current Address
Sanitizer uses heuristics to determine struct pthread size.
It does not depend on its precise layout. It merely scans for
pointers allocated using malloc.
Due to the removal of the padding, the assert for its start
is no longer required.
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
The current DSO dependency sorting tests are for a limited number of
specific cases, including some from particular bug reports.
Add tests that systematically cover all possible DAGs for an
executable and the shared libraries it depends on, directly or
indirectly, up to four objects (an executable and three shared
libraries). (For this kind of DAG - ones with a single source vertex
from which all others are reachable, and an ordering on the edges from
each vertex - there are 57 DAGs on four vertices, 3399 on five
vertices and 1026944 on six vertices; see
https://arxiv.org/pdf/2303.14710 for more details on this enumeration.
I've tested that the 3399 cases with five vertices do all pass if
enabled.)
These tests are replicating the sorting logic from the dynamic linker
(thereby, for example, asserting that it doesn't accidentally change);
I'm not claiming that the logic in the dynamic linker is in some
abstract sense optimal. Note that these tests do illustrate how in
some cases the two sorting algorithms produce different results for a
DAG (I think all the existing tests for such differences are ones
involving cycles, and the motivation for the new algorithm was also to
improve the handling of cycles):
tst-dso-ordering-all4-44: a->[bc];{}->[cba]
output(glibc.rtld.dynamic_sort=1): c>b>a>{}<a<b<c
output(glibc.rtld.dynamic_sort=2): b>c>a>{}<a<c<b
They also illustrate that sometimes the sorting algorithms do not
follow the order in which dependencies are listed in DT_NEEDED even
though there is a valid topological sort that does follow that, which
might be counterintuitive considering that the DT_NEEDED ordering is
followed in the simplest cases:
tst-dso-ordering-all4-56: {}->[abc]
output: c>b>a>{}<a<b<c
shows such a simple case following DT_NEEDED order for destructor
execution (the reverse of it for constructor execution), but
tst-dso-ordering-all4-41: a->[cb];{}->[cba]
output: c>b>a>{}<a<b<c
shows that c and b are in the opposite order to what might be expected
from the simplest case, though there is no dependency requiring such
an opposite order to be used.
(I'm not asserting that either of those things is a problem, simply
observing them as less obvious properties of the sorting algorithms
shown up by these tests.)
Tested for x86_64.
This change implements vfork.S for direct support of the vfork
syscall. clone.S is revised to correct child support for the
vfork case.
The main bug was creating a frame prior to the clone syscall.
This was done to allow the rp and r4 registers to be saved and
restored from the stack frame. r4 was used to save and restore
the PIC register, r19, across the system call and the call to
set errno. But in the vfork case, it is undefined behavior
for the child to return from the function in which vfork was
called. It is surprising that this usually worked.
Syscalls on hppa save and restore rp and r19, so we don't need
to create a frame prior to the clone syscall. We only need a
frame when __syscall_error is called. We also don't need to
save and restore r19 around the call to $$dyncall as r19 is not
used in the code after $$dyncall.
This considerably simplifies clone.S.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
There are no new constants covered by tst-mman-consts.py,
tst-mount-consts.py or tst-pidfd-consts.py in Linux 6.12 that need any
header changes, so update the kernel version in those tests.
(tst-sched-consts.py will need updating separately along with adding
SCHED_EXT.)
Tested with build-many-glibcs.py.
The CORE-MATH implementation is correctly rounded (for any rounding mode),
although it should worse performance than current one. The current
implementation performance comes mainly from the internal usage of
the optimize expf implementation, and shows a maximum ULPs of 2 for
FE_TONEAREST and 3 for other rounding modes.
The code was adapted to glibc style and to use the definition of
math_config.h (to handle errno, overflow, and underflow).
Benchtest on x64_64 (Ryzen 9 5900X, gcc 14.2.1), aarch64 (Neoverse-N1,
gcc 13.3.1), and powerpc (POWER10, gcc 13.2.1):
Latency master patched improvement
x86_64 40.6995 49.0737 -20.58%
x86_64v2 40.5841 44.3604 -9.30%
x86_64v3 39.3879 39.7502 -0.92%
i686 112.3380 129.8570 -15.59%
aarch64 (Neoverse) 18.6914 17.0946 8.54%
power10 11.1343 9.3245 16.25%
reciprocal-throughput master patched improvement
x86_64 18.6471 24.1077 -29.28%
x86_64v2 17.7501 20.2946 -14.34%
x86_64v3 17.8262 17.1877 3.58%
i686 64.1454 86.5645 -34.95%
aarch64 (Neoverse) 9.77226 12.2314 -25.16%
power10 4.0200 5.3316 -32.63%
Signed-off-by: Alexei Sibidanov <sibid@uvic.ca>
Signed-off-by: Paul Zimmermann <Paul.Zimmermann@inria.fr>
Signed-off-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Reviewed-by: DJ Delorie <dj@redhat.com>
The pi defined constants are not the expected value for atan2
on non-default rounding modes. Instead use the autogenerated value.
Reviewed-by: DJ Delorie <dj@redhat.com>
For some correctly rounded inputs where infinity might generate
a number (like atanf), comparing to a pre-defined constant does not
yield the expected result in all rounding modes.
The most straightforward way to handle it would be to get the expected
result from mpfr, where it handles all the rounding modes.
This will be required by the rseq extensible ABI implementation on all
Linux architectures exposing the '__rseq_size' and '__rseq_offset'
symbols to set the initial value of the 'cpu_id' field which can be used
by applications to test if rseq is available and registered. As long as
the symbols are exposed it is valid for an application to perform this
test even if rseq is not yet implemented in libc for this architecture.
Compile tested with build-many-glibcs.py but I don't have access to any
hardware to run the tests.
Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Linux 6.12 has no new syscalls. Update the version number in
syscall-names.list to reflect that it is still current for 6.12.
Tested with build-many-glibcs.py.
Hide memset/bzero from compiler to silence Clang error:
./tester.c:1345:29: error: 'size' argument to memset is '0'; did you mean to transpose the last two arguments? [-Werror,-Wmemset-transposed-args]
1345 | (void) memset(one+2, 'y', 0);
| ^
./tester.c:1345:29: note: parenthesize the third argument to silence
./tester.c:1432:16: error: 'size' argument to bzero is '0' [-Werror,-Wsuspicious-bzero]
1432 | bzero(one+2, 0);
| ^
./tester.c:1432:16: note: parenthesize the second argument to silence
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Reviewed-by: Sam James <sam@gentoo.org>
Set have-test-clang to yes if clang is used to test glibc. Set
have-test-clangxx to yes if clang++ is used to test glibc.
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Reviewed-by: Sam James <sam@gentoo.org>
Although _chk functions are exported in libc.so.6, their prototypes aren't
provided. Their built versions are supported by compiler. Replace
__strcpy_chk with __builtin___strcpy_chk to silence Clang error:
./tst-gnuglob-skeleton.c:225:3: error: call to undeclared function '__strcpy_chk'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
225 | __strcpy_chk (dir->d.d_name, filesystem[dir->idx].name, NAME_MAX);
| ^
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
The C standard requires that ungetc guarantees at least one pushback,
but the malloc call to allocate the pushback buffer could fail, thus
violating that requirement. Fix this by adding a single byte pushback
buffer in the FILE struct that the pushback can fall back to if malloc
fails.
The side-effect is that if the initial malloc fails and the 1-byte
fallback buffer is used, future resizing (if it succeeds) will be
2-bytes, 4-bytes and so on, which is suboptimal but it's after a malloc
failure, so maybe even desirable.
A future optimization here could be to have the pushback code use the
single byte buffer first and only fall back to malloc for subsequent
calls.
Signed-off-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
Reviewed-by: Maciej W. Rozycki <macro@redhat.com>
Clang does not define _Bool for -std=c++98:
/usr/include/bits/platform/features.h:31:19: error: unknown type name '_Bool'
31 | static __inline__ _Bool
| ^
Change _Bool to bool to silence clang++ error.
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Reviewed-by: Florian Weimer <fweimer@redhat.com>
GCC 4.9 issues an error for copysign in initializer:
In file included from tst-printf-format-p-double.c:20:0:
tst-printf-format-skeleton-double.c:29:3: error: initializer element is not a constant expression [-Werror]
{ -HUGE_VAL, -DBL_MAX, -DBL_MIN, copysign (0, -1), -NAN, NAN, 0, DBL_MIN,
^
since it can't fold "copysign (0, -1)". Replace copysign (0,-1) with -0.0.
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Add explicit instantiation declaration of S<char>::i to silence Clang
error:
tst-unique3.cc:6:18: error: instantiation of variable 'S<char>::i' required here, but no definition is available [-Werror,-Wundefined-var-template]
6 | int t = S<char>::i;
| ^
./tst-unique3.h:5:14: note: forward declaration of template entity is here
5 | static int i;
| ^
tst-unique3.cc:6:18: note: add an explicit instantiation declaration to suppress this warning if 'S<char>::i' is explicitly instantiated in another translation unit
6 | int t = S<char>::i;
| ^
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
ieee_long_double_shape_type has
typedef union
{
long double value;
struct
{
...
int sign_exponent:16;
...
} parts;
} ieee_long_double_shape_type;
Clang issues an error:
../sysdeps/ieee754/ldbl-96/test-totalorderl-ldbl-96.c:49:2: error: implicit truncation from 'int' to bit-field changes value from 65535 to -1 [-Werror,-Wbitfield-constant-conversion]
49 | SET_LDOUBLE_WORDS (ldnx, 0xffff,
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
50 | tests[i] >> 32, tests[i] & 0xffffffffULL);
|
Use -1, instead of 0xffff, to silence Clang.
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Reviewed-by: Sam James <sam@gentoo.org>
