There is no need to issue another sigaction if the disposition is
already SIG_DFL.
Checked on x86_64-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Occurs when `src` has no null-term.
Two cases:
1) Zero-length check is doing:
```
test %rdx, %rdx
jl L(zero_len)
```
which doesn't actually check zero (was at some point `decq` and the
flag never got updated).
The fix is just make the flag `jle` i.e:
```
test %rdx, %rdx
jle L(zero_len)
```
2) Length check in page-cross case checking if we should continue is
doing:
```
cmpq %r8, %rdx
jb L(page_cross_small)
```
which means we will continue searching for null-term if length ends at
the end of a page and there was no null-term in `src`.
The fix is to make the flag:
```
cmpq %r8, %rdx
jbe L(page_cross_small)
```
Thank Yinyu Cai for their maintainership of the LoongArch port.
Thank Vineet Gupta for their maintainership of the ARC port.
Thank Tulio Magno Quites Machado Filho for their past maintainership
of the PowerPC port.
Thank Rajalakshmi Srinivasaraghavan for their current maintainership
of the PowerPC port.
The __printf_buffer_flush_dprintf function needs to record that
the buffer has been written before reusing it. Without this
accounting, dprintf always returns zero.
Fixes commit 8ece45e4f5
("libio: Convert __vdprintf_internal to buffers").
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
This patch makes build-many-glibcs.py use the new MPFR 4.2.0 and MPC
1.3.1 releases.
Tested with build-many-glibcs.py (host-libraries, compilers and glibcs
builds).
This shows up as an assertion failure when sprintf is called with
a specifier like "%.8g" and libquadmath is linked in:
Fatal glibc error: printf_buffer_as_file.c:31
(__printf_buffer_as_file_commit): assertion failed:
file->stream._IO_write_ptr <= file->next->write_end
Fix this by detecting pointer wraparound in __vsprintf_internal
and saturate the addition to the end of the address space instead.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
All AMD architectures cache details will be computed based on
__cpuid__ `0x8000_001D` and the reference to __cpuid__ `0x8000_0006` will be
zeroed out for future architectures.
Reviewed-by: Premachandra Mallappa <premachandra.mallappa@amd.com>
Linux 6.1 adds a define IPPROTO_L2TP to its include/uapi/linux/in.h
(not strictly a new constant, since it's moved from
include/uapi/linux/l2tp.h). Add this constant to glibc's
netinet/in.h.
Tested for x86_64.
Use shrn for narrowing the mask which simplifies code and speeds up small
strings. Unroll the first search loop to improve performance on large
strings.
Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
Optimize strnlen using the shrn instruction and improve the main loop.
Small strings are around 10% faster, large strings are 40% faster on
modern CPUs.
Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
Simplify calculation of the mask using shrn. Unroll the main loop.
Small strings are 20% faster on modern CPUs.
Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
Use shrn for the mask, merge tst+bne into cbnz, and tweak code alignment.
Performance improves slightly as a result.
Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
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).
The 73fc4e28b9 refactor did not add the GL(dl_phdr) and
GL(dl_phnum) for static build, relying on the __ehdr_start symbol,
which is always added by the static linker, to get the correct values.
This is problematic in some ways:
- The segment may see its in-memory size differ from its in-file
size (or the binary may have holes). The Linux has fixed is to
provide concise values for both AT_PHDR and AT_PHNUM (commit
0da1d5002745c - "fs/binfmt_elf: Fix AT_PHDR for unusual ELF files")
- Some archs (alpha for instance) the hidden weak reference is not
correctly pulled by the static linker and __ehdr_start address
end up being 0, which makes GL(dl_phdr) and GL(dl_phnum) have both
invalid values (and triggering a segfault later on libc.so while
accessing TLS variables).
The safer fix is to just restore the previous behavior to setup
GL(dl_phdr) and GL(dl_phnum) for static based on kernel auxv. The
__ehdr_start fallback can also be simplified by not assuming weak
linkage (as for PIE).
The libc-static.c auxv init logic is moved to dl-support.c, since
the later is build without SHARED and then GLRO macro is defined
to access the variables directly.
The _dl_phdr is also assumed to be always non NULL, since an invalid
NULL values does not trigger TLS initialization (which is used in
various libc systems).
Checked on aarch64-linux-gnu, x86_64-linux-gnu, and i686-linux-gnu.
Reviewed-by: Florian Weimer <fweimer@redhat.com>
When compiling with GCC 6+ the sparc build warns that some variables
might be used uninitialized. However it does not seem the fact, since
the variables are really initialized (and also other targets that use the
same code, like powerpc, do not warn about it).
So suppress the warning for now.
Changes from v1:
* Update patch description and the explanation for the suppresion.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
The only way to override LD, AR, OBJCOPY, and GPROF is through
--with-binutils (setting the environments variables on configure is
overridden by LIBC_PROG_BINUTILS).
The build-many-glibcs.py (bmg) glibcs option generates a working config,
but not fully concise (some tools will be set from environment variable,
while other will be set from $CC --print-prog-name). So remove the
environment variable set to always use the "$CC --print-prog-name".
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
The patch suppress the same warnings from 87c266d758,
that shows issues for microblaze, mips soft-fp, nios2, and or1k.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
The buffer used by snprintf might not be large enough for all possible
inputs, as indicated by gcc with -O1:
../locale/programs/linereader.c: In function ‘utf8_sequence_error’:
../locale/programs/linereader.c:713:58: error: ‘%02x’ directive output
may be truncated writing between 2 and 8 bytes into a region of size
between 1 and 13 [-Werror=format-truncation=]
713 | snprintf (buf, sizeof (buf), "0x%02x 0x%02x 0x%02x 0x%02x",
| ^~~~
../locale/programs/linereader.c:713:34: note: directive argument in the
range [0, 2147483647]
713 | snprintf (buf, sizeof (buf), "0x%02x 0x%02x 0x%02x 0x%02x",
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
../locale/programs/linereader.c:713:5: note: ‘snprintf’ output between
20 and 38 bytes into a destination of size 30
713 | snprintf (buf, sizeof (buf), "0x%02x 0x%02x 0x%02x 0x%02x",
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
714 | ch1, ch2, ch3, ch4);
| ~~~~~~~~~~~~~~~~~~~
Checked on x86_64-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
There have been multiple requests to provide more detail on how the
_FORTIFY_SOURCE macro works, so this patch adds a new node in the
Library Maintenance section that does this. A lot of the description is
implementation detail, which is why I put this in the appendix and not
in the main documentation.
Resolves: BZ #28998.
Signed-off-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
Reviewed-by: Florian Weimer <fweimer@redhat.com>
I've updated copyright dates in glibc for 2023. This is the patch for
the changes not generated by scripts/update-copyrights and subsequent
build / regeneration of generated files.
For some reason this causes a pre-commit check error for a copyright
date update commit, even though that commit doesn't touch anything
near the line with this whitespace.
<tgmath.h> implements semantics for integer generic arguments that
handle cases involving _FloatN / _FloatNx types as specified in TS
18661-3 plus some defect fixes.
C2x has further changes to the semantics for <tgmath.h> macros with
such types, which should also be considered defect fixes (although
handled through the integration of TS 18661-3 in C2x rather than
through an issue tracking process). Specifically, the rules were
changed because of problems raised with using the macros with the
evaluation format types such as float_t and _Float32_t: the older
version of the rules didn't allow passing _FloatN / _FloatNx types to
the narrowing macros returning float or double, or passing float /
double / long double to the narrowing macros returning _FloatN /
_FloatNx, which was a problem with the evaluation format types which
could be either kind of type depending on the value of
FLT_EVAL_METHOD.
Thus the new rules allow cases of mixing types which were not allowed
before, and, as part of the changes, the handling of integer arguments
was also changed: if there is any _FloatNx generic argument, integer
generic arguments are treated as _Float32x (not double), while the
rule about treating integer arguments to narrowing macros returning
_FloatN or _FloatNx as _Float64 not double was removed (no longer
needed now double is a valid argument to such macros).
I've implemented the changes in GCC's __builtin_tgmath, which thus
requires updates to glibc's test expectations so that the tests
continue to build with GCC 13 (the test is also updated to test the
argument types that weren't allowed before but are now valid under C2x
rules).
Given those test changes, it's then also necessary to fix the
implementations in <tgmath.h> to have appropriate semantics with older
GCC so that the tests pass with GCC versions before GCC 13 as well.
For some cases (non-narrowing macros with two or three generic
arguments; narrowing macros returning _Float32x), the older version of
__builtin_tgmath doesn't correspond sufficiently well to C2x
semantics, so in those cases <tgmath.h> is adjusted to use the older
macro implementation instead of __builtin_tgmath. The older macro
implementation is itself adjusted to give the desired semantics, with
GCC 7 and later. (It's not possible to get the right semantics in all
cases for the narrowing macros with GCC 6 and before when the _FloatN
/ _FloatNx names are typedefs rather than distinct types.)
Tested as follows: with the full glibc testsuite for x86_64, GCC 6, 7,
11, 13; with execution of the math/tests for aarch64, arm, powerpc and
powerpc64le, GCC 6, 7, 12 and 13 (powerpc64le only with GCC 12 and
13); with build-many-glibcs.py with GCC 6, 7, 12 and 13.
The daylight variable is supposed to be set to 1 if DST is ever in
use for the current time zone. But __tzfile_read used to do this:
__daylight = rule_stdoff != rule_dstoff;
This check can fail to set __daylight to 1 if the DST and non-DST
offsets happen to be the same.
