Uros Bizjak [Thu, 9 Oct 2025 18:44:17 +0000 (20:44 +0200)]
x86_64: Use __seg_fs qualifiers in PTR_{MANGLE,DEMANGLE}() macros
Use __seg_fs named address space qualifiers in PTR_MANGLE() and
PTR_DEMANGLE() macros to access the pointer_guard field in the TCB.
This change allows the compiler to eliminate redundant reads of
the variable, reducing the number of reads from 98 to 89 and
decreasing the text size of the library by 512 bytes.
While at it, fix a few trivial whitespace issues as well.
Signed-off-by: Uros Bizjak <ubizjak@gmail.com> Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
Sergey Kolosov [Fri, 10 Oct 2025 15:15:27 +0000 (17:15 +0200)]
resolv: Add tests for getaddrinfo returning EAI_AGAIN [BZ #16849]
This patch adds two tests that verify correct behavior of getaddrinfo
when DNS resolution fails with a temporary error. Both tests ensure
that getaddrinfo returns EAI_AGAIN in cases where no valid address can
be resolved due to network or resolver failure.
* tst-getaddrinfo-eai-again.c
Runs inside the glibc test-container without any DNS server
configured. The test performs queries using AF_INET, AF_INET6,
and AF_UNSPEC and verifies that getaddrinfo returns EAI_AGAIN
when resolution fails.
* tst-getaddrinfo-eai-again-timeout.c
Runs outside of the container but uses the resolv_test framework
to simulate network failures. The test covers two failure modes:
- No response from the server (resolv_response_drop)
- Zero-length reply from the server
In both cases, getaddrinfo is expected to return EAI_AGAIN.
Ben Boeckel [Wed, 1 Oct 2025 13:39:08 +0000 (09:39 -0400)]
elf: Report when found libraries are rejected [BZ #25669]
When debugging library loading issues with `LD_DEBUG`, it can be
frustrating to see logs for files in a directory are searched, but the
target library is skipped over without any indication of why. Add
reporting to all paths which reject a library as `ENOENT`.
Originally created for minimum-OS version detection, but that has since
been removed in b46d250656 (Remove kernel version check, 2022-02-21).
The remaining codepaths are still useful.
Signed-off-by: Ben Boeckel <ben.boeckel@kitware.com> Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Dev Jain [Wed, 8 Oct 2025 12:47:12 +0000 (12:47 +0000)]
malloc: Do not call madvise if oldsize >= THP size
Linux handles virtual memory in Virtual Memory Areas (VMAs). The
madvise(MADV_HUGEPAGE) call works on a VMA granularity, which sets the
VM_HUGEPAGE flag on the VMA. If this VMA or a portion of it is mremapped
to a different location, Linux will create a new VMA, which will have
the same flags as the old one. This implies that the VM_HUGEPAGE flag
will be retained. Therefore, if we can guarantee that the old VMA was
marked with VM_HUGEPAGE, then there is no need to call madvise_thp() in
mremap_chunk().
The old chunk comes from a heap or non-heap allocation, both of which
have already been enlightened for THP. This implies that, if THP is on,
and the size of the old chunk is greater than or equal to thp_pagesize,
the VMA to which this chunk belongs to, has the VM_HUGEPAGE flag set.
Hence in this case we can avoid invoking the madvise() syscall.
Wilco Dijkstra [Wed, 1 Oct 2025 17:43:11 +0000 (17:43 +0000)]
malloc: Improve mmap interface
Add mmap_set_chunk() to create a new chunk from an mmap block.
Remove set_mmap_is_hp() since it is done inside mmap_set_chunk().
Rename prev_size_mmap() to mmap_base_offset(). Cleanup comments.
Wilco Dijkstra [Fri, 3 Oct 2025 18:36:00 +0000 (18:36 +0000)]
atomic: Remove atomic_forced_read
Remove the odd atomic_forced_read which is neither atomic nor forced.
Some uses are completely redundant, so simply remove them. In other cases
the intended use is to force a memory ordering, so use acquire load for those.
In yet other cases their purpose is unclear, for example __nscd_cache_search
appears to allow concurrent accesses to the cache while it is being garbage
collected by another thread! Use relaxed atomic loads here to block spills
from accidentally reloading memory that is being changed.
Uros Bizjak [Wed, 1 Oct 2025 09:07:31 +0000 (11:07 +0200)]
x86: Use typeof_member style in RSEQ area access expressions
Update RSEQ access macros to use `(struct rseq_area) {}.member`
in _Static_assert and __typeof expressions, instead of
RSEQ_SELF()->member. This adopts the typeof_member style, avoiding
reliance on RSEQ_SELF for compile-time expressions.
Signed-off-by: Uros Bizjak <ubizjak@gmail.com> Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
Replace manual cast with a direct
`(struct rseq_area __seg_gs *)__rseq_offset` dereference to access
`member`. This avoids redundant `offsetof(struct rseq_area, member)`
and improves readability while preserving semantics.
Signed-off-by: Uros Bizjak <ubizjak@gmail.com> Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
Replace manual casts with a direct `(__tcbhead_t __seg_gs *)0`
dereferences for `stack_guard` and `pointer_guard`. This makes
the macros more straightforward and removes the dependency on
<stdint.h>.
Signed-off-by: Uros Bizjak <ubizjak@gmail.com> Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
Replace manual cast with a direct `(__typeof(*descr) __seg_gs *)0`
dereference to access `member`. This avoids redundant
`offsetof(struct pthread, member)` and improves readability while
preserving semantics.
Signed-off-by: Uros Bizjak <ubizjak@gmail.com> Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
Yury Khrustalev [Fri, 20 Jun 2025 12:37:34 +0000 (13:37 +0100)]
manual: describe syscall numbers not supported via syscall()
The syscall() function allows to make system calls directly, however,
in the case of system calls that affect internal state of process or
thread, the caller would have to take care of extensive setup necessary
for the internals of Glibc to work correctly in the child threads. This
may make using syscall() with these syscall numbers impractical and
prone to undefined behaviour.
Bruno Haible [Mon, 6 Oct 2025 04:01:49 +0000 (21:01 -0700)]
manual: fix some mistakes in the indices [BZ #24657]
* manual/errno.texi (Error Messages): Add error_print_progname to the
variable index.
* manual/sysinfo.texi (Host Identification): Fix typo of the
getdomainname function.
arm: Add ARM VFPv4 VFMA instruction support in fma/fmaf (BZ 15503)
It is enabled through math-use-builtins-fma.h if glibc is built
for VPFv4 (__ARM_FEATURE_FMA predefined by GCC), or through IFUNC
(testing HWCAP_ARM_VFPv4) otherwise.
With same micro-optimization done for the double variant:
* Combine the |y| zero check.
* Rework the check to adjust result and call fmod.
* Remove one check after fmod.
* Remove float-int-float roundtrip on return.
Also use math_config.h macros and indent the code. The resulting
strategy is different in many places that I think requires a
different Copyright.
I see the following performance improvements using remainder benchtests
(using reciprocal-throughput metric):
The commit 34b9f8bc17 provides an optimized fmod implementation; use
the same strategy used for remainderf and implement the double variant
on top of fmod.
I see the following performance improvements using remainder benchtests
(using reciprocal-throughput metric):
William Hunt [Fri, 3 Oct 2025 16:27:35 +0000 (16:27 +0000)]
malloc: Cleanup macros, asserts and sysmalloc_mmap_fallback
Refactor malloc.c to remove dead code, create macros to abstract duplicated
code, and cleanup sysmalloc_mmap_fallback to remove logic not related to the
mmap call.
Change the return type of mmap_base to uintptr_t since this allows using
operations on the return value, and avoids casting in both calls in
mremap_chunk and munmap_chunk.
Cleanup sysmalloc_mmap_fallback. Remove unused parameters nb, oldsize
and av. Remove redundant overflow check and instead use size_t for all
parameters except extra_flags to prevent overflows. Move logic not concerned
with the mmap call itself outside the function after both calls to
sysmalloc_mmap_fallback are made; this means move code for naming the VMA
and marking the arena being extended as non-contiguous to the calling code to
be handled in the case that the mmap is successful. Calculate the fallback
size from nb to avoid modifying size after it has been set for MORECORE.
Remove unused noncontiguous macro.
Remove redundant assert for checking unreachable option for global_max_fast.
When compiling on x86_64 with -Wshift-overflow=2 you can see the
following warning:
../sysdeps/ieee754/flt-32/math_config.h: In function ‘is_inf’:
../sysdeps/ieee754/flt-32/math_config.h:184:37: warning: result of ‘2139095040 << 1’ requires 33 bits to represent, but ‘int’ only has 32 bits [-Wshift-overflow=]
184 | return (x << 1) == (EXPONENT_MASK << 1);
| ^~
This patch adjusts the definitions to use UINT32_C. This matches the
definitions in sysdeps/ieee754/dbl-64/math_config.h which use UINT64_C
for these definitions.
shm-directory: Truncated struct member name length
The struct shmdir_name in include/shm-directory.h has name field to
contains the full path of the POSIX IPC object (shm and sem).
The size was previously set to sizeof (SHMDIR) + 4 + NAME_MAX, where 4
bytes were reserved for the optional "sem." prefix.
This led to incorrect execution of the __shm_get_name function
in posix/shm-directory.c which is used accross in shm_[open/unlink] and
sem_[open/unlink] functions.
For shm_[open/unlink]:
This is because the name field was large enough to hold 268 characters
(255 + 4 + 9) instead of the maximum allowed 263 characters (255 + 9).
This caused the __shm_get_name to not throw ENAMETOOLONG error when the
name length exceeded NAME_MAX (255) upto 259 characters.
For sem_[open/unlink]:
Similarly, the __shm_get_name incorrectly returned success for names of
length 255 instead of 251 (255 - 4).
This was overlooked as finally these functions throw the correct
ENAMETOOLONG error; which was thrown by the openat syscall, which is
called later in the shm_* and sem_* functions.
This patch corrects the size of name field in struct shmdir_name to
sizeof (SHMDIR) + NAME_MAX. The __shm_get_name function return
ENAMETOOLONG if alloc_buffer_has_failed returns true (which only happens
when copy length > alloc_buffer_size (buffer)).
Relevant runtime monitoring were done in gdb to confirm the same.
Joseph Myers [Wed, 1 Oct 2025 15:15:15 +0000 (15:15 +0000)]
Add once_flag, ONCE_FLAG_INIT and call_once to stdlib.h for C23
C23 adds once_flag, ONCE_FLAG_INIT and call_once to stdlib.h (in C11
they were only in threads.h, in C23 they are in both headers; this
change came from N2840). Implement this change, with a
bits/types/once_flag.h header for the common type and initializer
definitions.
Note that there's an omnibus bug (bug 33001) that covers more than
just these missing definitions.
This doesn't seem a significant enough feature to be worth mentioning
in NEWS.
ISO C is not concerned with whether functions are in libc or
libpthread, but POSIX links this to what header they are declared in,
so functions declared in stdlib.h are supposed to be in libc.
However, the current edition of POSIX is based on C17; hopefully Hurd
glibc will have completed the merge of libpthread into libc (in
particular, moving call_once) well before a future edition of POSIX
based on C23 (or a later version of ISO C) is released.
Joseph Myers [Wed, 1 Oct 2025 15:14:09 +0000 (15:14 +0000)]
Implement C23 memset_explicit (bug 32378)
Add the C23 memset_explicit function to glibc. Everything here is
closely based on the approach taken for explicit_bzero. This includes
the bits that relate to internal uses of explicit_bzero within glibc
(although we don't currently have any such internal uses of
memset_explicit), and also includes the nonnull attribute (when we
move to nonnull_if_nonzero for various functions following C2y, this
function should be included in that change).
The function is declared both for __USE_MISC and for __GLIBC_USE (ISOC23)
(so by default not just for compilers defaulting to C23 mode).
manual: Fix missing declaration in inetcli example.
Previously this file failed to compile with the following errors:
$ gcc manual/examples/inetcli.c
manual/examples/inetcli.c: In function ‘write_to_server’:
manual/examples/inetcli.c:36:37: error: implicit declaration of function ‘strlen’ [-Wimplicit-function-declaration]
36 | nbytes = write (filedes, MESSAGE, strlen (MESSAGE) + 1);
| ^~~~~~
manual/examples/inetcli.c:26:1: note: include ‘<string.h>’ or provide a declaration of ‘strlen’
25 | #include <netdb.h>
+++ |+#include <string.h>
26 |
manual/examples/inetcli.c:36:37: warning: incompatible implicit declaration of built-in function ‘strlen’ [-Wbuiltin-declaration-mismatch]
36 | nbytes = write (filedes, MESSAGE, strlen (MESSAGE) + 1);
| ^~~~~~
manual/examples/inetcli.c:36:37: note: include ‘<string.h>’ or provide a declaration of ‘strlen’
Previously this file failed to compile with the following errors:
$ gcc manual/examples/inetsrv.c
manual/examples/inetsrv.c: In function ‘main’:
manual/examples/inetsrv.c:97:31: error: passing argument 3 of ‘accept’ from incompatible pointer type [-Wincompatible-pointer-types]
97 | &size);
| ^~~~~
| |
| size_t * {aka long unsigned int *}
In file included from manual/examples/inetsrv.c:23:
/usr/include/sys/socket.h:307:42: note: expected ‘socklen_t * restrict’ {aka ‘unsigned int * restrict’} but argument is of type ‘size_t *’ {aka ‘long unsigned int *’}
307 | socklen_t *__restrict __addr_len);
| ~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~
manual/examples/inetsrv.c:105:26: error: implicit declaration of function ‘inet_ntoa’ [-Wimplicit-function-declaration]
105 | inet_ntoa (clientname.sin_addr),
Previously this file failed to compile with the following errors:
$ gcc manual/examples/filesrv.c
manual/examples/filesrv.c: In function ‘main’:
manual/examples/filesrv.c:37:3: error: implicit declaration of function ‘unlink’ [-Wimplicit-function-declaration]
37 | unlink (SERVER);
| ^~~~~~
manual/examples/filesrv.c:40:10: error: implicit declaration of function ‘make_named_socket’ [-Wimplicit-function-declaration]
40 | sock = make_named_socket (SERVER);
| ^~~~~~~~~~~~~~~~~
manual/examples/filesrv.c:46:54: error: passing argument 6 of ‘recvfrom’ from incompatible pointer type [-Wincompatible-pointer-types]
46 | (struct sockaddr *) & name, &size);
| ^~~~~
| |
| size_t * {aka long unsigned int *}
In file included from manual/examples/filesrv.c:21:
/usr/include/sys/socket.h:165:48: note: expected ‘socklen_t * restrict’ {aka ‘unsigned int * restrict’} but argument is of type ‘size_t *’ {aka ‘long unsigned int *’}
165 | socklen_t *__restrict __addr_len);
| ~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~
This patch fixes the missing declaration for unlink and uses
'socklen_t *' for the fourth argument of recv from. The
make_named_socket function is defined in the manual.
manual: Fix missing declaration in setjmp example.
Previously this file would fail to compile with the following error:
$ gcc manual/examples/setjmp.c
manual/examples/setjmp.c: In function ‘main’:
manual/examples/setjmp.c:37:7: error: implicit declaration of function ‘do_command’ [-Wimplicit-function-declaration]
37 | do_command ();
| ^~~~~~~~~~
manual/examples/setjmp.c: At top level:
manual/examples/setjmp.c:42:1: warning: conflicting types for ‘do_command’; have ‘void(void)’
42 | do_command (void)
| ^~~~~~~~~~
manual/examples/setjmp.c:37:7: note: previous implicit declaration of ‘do_command’ with type ‘void(void)’
37 | do_command ();
| ^~~~~~~~~~
manual: Fix missing declaration in strdupa example.
Without _GNU_SOURCE defined this file fails to compile with the
following error:
$ gcc manual/examples/strdupa.c
manual/examples/strdupa.c: In function ‘main’:
manual/examples/strdupa.c:27:19: error: implicit declaration of function ‘strdupa’; did you mean ‘strdup’? [-Wimplicit-function-declaration]
27 | char *wr_path = strdupa (path);
| ^~~~~~~
| strdup
manual/examples/strdupa.c:27:19: error: initialization of ‘char *’ from ‘int’ makes pointer from integer without a cast [-Wint-conversion]
Previously this file would fail to compile with the following error:
$ gcc manual/examples/memopen.c
manual/examples/memopen.c: In function ‘main’:
manual/examples/memopen.c:28:30: error: implicit declaration of function ‘strlen’ [-Wimplicit-function-declaration]
28 | stream = fmemopen (buffer, strlen (buffer), "r");
| ^~~~~~
manual/examples/memopen.c:19:1: note: include ‘<string.h>’ or provide a declaration of ‘strlen’
18 | #include <stdio.h>
+++ |+#include <string.h>
19 |
manual/examples/memopen.c:28:30: warning: incompatible implicit declaration of built-in function ‘strlen’ [-Wbuiltin-declaration-mismatch]
28 | stream = fmemopen (buffer, strlen (buffer), "r");
| ^~~~~~
manual/examples/memopen.c:28:30: note: include ‘<string.h>’ or provide a declaration of ‘strlen’
Without _GNU_SOURCE defined this file fails to compile with the
following error:
$ gcc manual/examples/twalk.c
manual/examples/twalk.c: In function ‘twalk’:
manual/examples/twalk.c:55:3: error: implicit declaration of function ‘twalk_r’; did you mean ‘twalk’? [-Wimplicit-function-declaration]
55 | twalk_r (root, twalk_with_twalk_r_action, &closure);
| ^~~~~~~
| twalk
Previously this file would fail to compile with the following error:
$ gcc manual/examples/sigusr.c
manual/examples/sigusr.c: In function ‘child_function’:
manual/examples/sigusr.c:46:3: error: implicit declaration of function ‘exit’ [-Wimplicit-function-declaration]
46 | exit (0);
| ^~~~
manual/examples/sigusr.c:23:1: note: include ‘<stdlib.h>’ or provide a declaration of ‘exit’
22 | #include <unistd.h>
+++ |+#include <stdlib.h>
23 | /*@end group*/
manual/examples/sigusr.c:46:3: warning: incompatible implicit declaration of built-in function ‘exit’ [-Wbuiltin-declaration-mismatch]
46 | exit (0);
| ^~~~
manual/examples/sigusr.c:46:3: note: include ‘<stdlib.h>’ or provide a declaration of ‘exit’
manual: Fix missing includes in the mbstouwcs example.
Previously this file would fail to compile with the following error:
$ gcc manual/examples/mbstouwcs.c
manual/examples/mbstouwcs.c: In function ‘mbstouwcs’:
manual/examples/mbstouwcs.c:34:11: error: ‘errno’ undeclared (first use in this function)
34 | errno = EILSEQ;
| ^~~~~
manual/examples/mbstouwcs.c:5:1: note: ‘errno’ is defined in header ‘<errno.h>’; this is probably fixable by adding ‘#include <errno.h>’
4 | #include <wchar.h>
+++ |+#include <errno.h>
5 |
manual/examples/mbstouwcs.c:34:11: note: each undeclared identifier is reported only once for each function it appears in
34 | errno = EILSEQ;
| ^~~~~
manual/examples/mbstouwcs.c:34:19: error: ‘EILSEQ’ undeclared (first use in this function)
34 | errno = EILSEQ;
| ^~~~~~
manual/examples/mbstouwcs.c:47:20: error: implicit declaration of function ‘towupper’ [-Wimplicit-function-declaration]
47 | *wcp++ = towupper (wc);
| ^~~~~~~~
manual/examples/mbstouwcs.c:5:1: note: include ‘<wctype.h>’ or provide a declaration of ‘towupper’
4 | #include <wchar.h>
+++ |+#include <wctype.h>
5 |
manual/examples/mbstouwcs.c:47:20: warning: incompatible implicit declaration of built-in function ‘towupper’ [-Wbuiltin-declaration-mismatch]
47 | *wcp++ = towupper (wc);
| ^~~~~~~~
manual/examples/mbstouwcs.c:47:20: note: include ‘<wctype.h>’ or provide a declaration of ‘towupper’
manual: Fix missing include in group and user database example.
Previously this file would fail to compile with the following error:
$ gcc manual/examples/db.c
db.c: In function ‘main’:
db.c:37:7: error: implicit declaration of function ‘printf’ [-Wimplicit-function-declaration]
37 | printf ("Couldn't find out about user %d.\n", (int) me);
| ^~~~~~
db.c:23:1: note: include ‘<stdio.h>’ or provide a declaration of ‘printf’
22 | #include <stdlib.h>
+++ |+#include <stdio.h>
23 |
db.c:37:7: warning: incompatible implicit declaration of built-in function ‘printf’ [-Wbuiltin-declaration-mismatch]
37 | printf ("Couldn't find out about user %d.\n", (int) me);
| ^~~~~~
db.c:37:7: note: include ‘<stdio.h>’ or provide a declaration of ‘printf’
db.c:42:3: warning: incompatible implicit declaration of built-in function ‘printf’ [-Wbuiltin-declaration-mismatch]
42 | printf ("I am %s.\n", my_passwd->pw_gecos);
| ^~~~~~
db.c:42:3: note: include ‘<stdio.h>’ or provide a declaration of ‘printf’
Linux: Fix tst-copy_file_range-large test on recent kernels [BZ #33498]
Instead of a negative return value the fixed FUSE copy_file_range will
silently truncate the size to UINT_MAX & PAGE_MASK [1]. Allow that value
to be returned as well.
fpu_control.h is an installed header so a wider range of compiler versions
(including ones older than GCC 9) are relevant with it than are relevant
for building glibc.
Jovan Dmitrovic [Wed, 3 Sep 2025 13:53:37 +0000 (13:53 +0000)]
mips: Remove strcmp.S
Testing strcmp on MIPS hardware shows that strcmp.S performs worse
than the combination of using the generic strcmp.c implementation
alongside -funroll-loops.
Suggested-by: Joseph Myers <josmyers@redhat.com> Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org> Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
It now calls __libc_assert, which contains similar logic. The assert
call only requires memory allocation for the message translation, so
test-assert2.c is adapted to handle it.
It also removes the fxprintf from assert/assert_perror; although it
is not 100% backwards-compatible (write message only if there is a
file descriptor associated with the stderr). It now writes bytes
directly without going through the wide stream state.
nptl: Fix MADV_GUARD_INSTALL logic for thread without guard page (BZ 33356)
The main issue is that setup_stack_prot fails to account for cases where
the cached thread stack lacks a guard page, which can cause madvise to
fail. Update the logic to also handle whether MADV_GUARD_INSTALL is
supported when resizing the guard page.
Checked on x86_64-linux-gnu with 6.8.0 and 6.15 kernels.
x86: Use "%v" to emit VEX encoded instructions for AVX targets
Legacy encodings of SSE instructions incur AVX-SSE domain transition
penalties on some Intel microarchitectures (e.g. Haswell, Broadwell).
Using the VEX forms avoids these penatlies and keeps all instructions
in the VEX decode domain. Use "%v" sequence to emit the "v" prefix
for opcodes when compiling with -mavx.
GCC now accept plain variable names as valid lvalues for "m"
constraints, automatically spilling locals to memory if necessary.
The long-standing "*&" pattern was originally used as a defensive
workaround for older compiler versions that rejected operands
such as:
asm ("incl %0" : "+m"(x));
with errors like "memory input is not directly addressable".
Modern compilers (GCC >= 9) reliably generate correct code
without the workaround, and the resulting assembly is identical.
Diego Nieto Cid [Fri, 15 Aug 2025 01:57:30 +0000 (02:57 +0100)]
hurd: implement RLIMIT_AS against Mach RPCs
Check for VM limit RPCs
* config.h.in: add #undef for HAVE_MACH_VM_GET_SIZE_LIMIT and
HAVE_MACH_VM_SET_SIZE_LIMIT.
* sysdeps/mach/configure.ac: use mach_RPC_CHECK to check for
vm_set_size_limit and vm_get_size_limit RPCs in gnumach.defs.
* sysdeps/mach/configure: regenerate file.
Use vm_get_size_limit to initialize RLIMIT_AS
* hurd/hurdrlimit.c(init_rlimit): use vm_get_size_limit to initialize
RLIMIT_AS entry of the _hurd_rlimits array.
Notify the kernel of the new VM size limits
* sysdeps/mach/hurd/setrlimit.c: use the vm_set_size_limit RPC,
if available, to notify the kernel of the new limits. Retry RPC
calls if they were interrupted by a signal.
Message-ID: <03fb90a795b354a366ee73f56f73e6ad22a86cda.1755220108.git.dnietoc@gmail.com>
Samuel Thibault [Sun, 21 Sep 2025 21:45:40 +0000 (23:45 +0200)]
hurd: catch SIGSEGV on returning from signal handler
On stack overflow typically, we may not actually have room on the stack to
trampoline back from the signal handler. We have to detect this before
locking the ss, otherwise the signal thread will be stuck on taking the
ss lock while trying to post SIGSEGV.
Remove support for obsolete dumped heaps. Dumping heaps was discontinued
8 years ago, however loading a dumped heap is still supported. This blocks
changes and improvements of the malloc data structures - hence it is time
to remove this. Ancient binaries that still call malloc_set_state will now
get the -1 error code. Update tst-mallocstate.c to just check for this.
The realpath call may trigger OOM termination of the test process
under difficult-to-predict circumstances. (It depends on available
RAM and swap.) Therefore, instruct the test driver to ignore
an OOM process termination during the realpath call.
support: Add support_accept_oom to heuristically support OOM errors
Some tests may trigger the kernel OOM handler under conditions
which are difficult to predict (depending on available RAM and
swap space). If we can determine specific regions which might
do this and this does not contradict the test object, the
functions support_accept_oom (true) and support_accept_oom (false)
can be called at the start and end, and the test driver will
ignore SIGKILL signals.
The "unused" variable could be use unitialized, which is an issue if ldd
is ran with "-u". Fix that by defining the variable to an empty value,
just like it is already done for the bind_now, warn and verbose
variables.
Reported-by: Johan Palmqvist <johan.palmqvist@gmail.com> Reviewed-by: Sam James <sam@gentoo.org>
which warns ‘-pg’ without ‘-mfentry’, when glibc is configured with
--disable-default-pie, GCC 16 fails to compile .op files and gmon tests
with error:
cc1: error: ‘-pg’ without ‘-mfentry’ may be unreliable with shrink wrapping [-Werror]
Compile .op files and gmon tests with -mfentry if it is supported by
CC/TEST_CC and glibc is configured with --disable-default-pie. This
fixes BZ #33376.
Signed-off-by: H.J. Lu <hjl.tools@gmail.com> Reviewed-by: Joseph Myers <josmyers@redhat.com>
i386: Use __seg_gs qualifier to cast access to TCB in THREAD_GSCOPE_RESET_FLAG()
Use the __seg_gs named address space qualifier to cast access to the
gscope_flag in the TCB as a %gs: prefixed address. This enables the
use of the "m" operand constraint, which informs the compiler about
memory access in the inline assembly.
x86_64: Use __seg_fs qualifier to cast access to TCB in THREAD_GSCOPE_RESET_FLAG()
Use the __seg_fs named address space qualifier to cast access to the
gscope_flag in the TCB as a %fs: prefixed address. This enables the
use of the "m" operand constraint, which informs the compiler about
memory access in the inline assembly.
Joseph Myers [Wed, 3 Sep 2025 16:30:11 +0000 (16:30 +0000)]
Fix RISC-V soft-float _FPU_SETCW for GCC 16 set-but-not-used warnings
The soft-float RISC-V definition of _FPU_SETCW results in a
-Werror=unused-but-set-variable= build failure with GCC mainline (in
math/setfpucw.c) because it does not use the dummy cw variable.
Change it to (void) (cw) as on other architectures to avoid this build
failure.
Tested with build-many-glibcs.py (compilers) for
riscv64-linux-gnu-rv64imac-lp64, which previously failed. Reviewed-by: Sam James <sam@gentoo.org>
nss: Group merge does not react to ERANGE during merge (bug 33361)
The break statement in CHECK_MERGE is expected to exit the surrounding
while loop, not the do-while loop with in the macro. Remove the
do-while loop from the macro. It is not needed to turn the macro
expansion into a single statement due to the way CHECK_MERGE is used
(and the statement expression would cover this anyway).
caiyinyu [Fri, 3 Jan 2025 07:23:46 +0000 (15:23 +0800)]
LoongArch: Use the generic shmlab.h.
The shmlba.h file related to the LoongArch architecture was introduced
in commit 3eed5f3a1ee to address the mismatch in the SHMLBA definition
between glibc and the kernel. See [1]. The SHMLBA definition was later
updated in commit d23b77953f5a. See [2]. Now, we adopt the definition
from the common layer.
LoongArch: Fix inconsistency in SHMLBA macro values between glibc and kernel
The LoongArch glibc was using the value of the SHMLBA macro from common code,
which is __getpagesize() (16k), but this was inconsistent with the value of
the SHMLBA macro in the kernel, which is SZ_64K (64k). This caused several
shmat-related tests in LTP (Linux Test Project) to fail. This commit fixes
the issue by ensuring that the glibc's SHMLBA macro value matches the value
used in the kernel like other architectures.
LoongArch has hardware page coloring for L1 Cache, so we don't have
cache aliases. But SFB (Store Fill Buffer) still has aliases. So we
define SHMLBA to SZ_64K previously. But there are losts of applications
use PAGE_SIZE rather than SHMLBA to mmap() file pages and shared pages.
Of course we can fix them one by one, but not easy.
On the other hand, we can simply disable SFB for 4KB page size to fix
cache alias (there will be performance decrease, but acceptable), and
in future we will fix SFB in hardware. So we can safely define SHMLBA to
PAGE_SIZE (use the generic shmparam.h) to make life easier.
alpha: Fix missing inexact-flag raising for lround/lrint
The l*[rint|round]f implements uses alpha 'cvtst/s', 'addt/suc',
adn 'cvttq/svd' which are not not fully IEEE compliant w.r.t
inexact-flag raising.. Use the software fallback implementation
instead.
Checked on alpha-linux-gnu.
Tested-by: Michael Cree <mcree@orcon.net.nz> Reviewed-by: Carlos O'Donell <carlos@redhat.com>
To avoid linknamespace issues on old standards. It is required
if the fallback fma implementation is used if/when it is also
used internally for other implementation. Reviewed-by: DJ Delorie <dj@redhat.com>
To avoid linknamespace issues on old standards. It is required
if the fallback fma implementation is used if/when it is also
used internally for other implementation. Reviewed-by: DJ Delorie <dj@redhat.com>
To avoid linknamespace issues on old standards. It is required
if the fallback fma implementation is used if/when it is also
used internally for other implementation. Reviewed-by: DJ Delorie <dj@redhat.com>
To avoid linknamespace issues on old standards. It is required
if the fallback fma implementation is used if/when it is also
used internally for other implementation. Reviewed-by: DJ Delorie <dj@redhat.com>
To avoid linknamespace issues on old standards. It is required
if the fallback fma implementation is used if/when it is also
used internally for other implementation. Reviewed-by: DJ Delorie <dj@redhat.com>
To avoid linknamespace issues on old standards. It is required
if the fallback fma implementation is used if/when it is also
used internally for other implementation. Reviewed-by: DJ Delorie <dj@redhat.com>
To avoid linknamespace issues on old standards. It is required
if the fallback fma implementation is used if/when it is also
used internally for other implementation. Reviewed-by: DJ Delorie <dj@redhat.com>
projects / thirdparty / glibc.git / log
