H.J. Lu [Thu, 30 Oct 2025 23:29:45 +0000 (07:29 +0800)]
Build programs in $(others-noinstall) like tests if libgcc_s is available
Build programs in $(others-noinstall) like tests only if libgcc_s is
available. Otherwise, "build-many-glibcs.py compilers" will fail to
build the initial glibc with the initial limited gcc due to the missing
libgcc_s.
Joseph Myers [Mon, 3 Nov 2025 19:56:42 +0000 (19:56 +0000)]
Support assert as a variadic macro for C23
C23 makes assert into a variadic macro to handle cases of an argument
that would be interpreted as a single function argument but more than
one macro argument (in particular, compound literals with an
unparenthesized comma in an initializer list); this change was made by
N2829. Note that this only applies to assert, not to other macros
specified in the C standard with particular numbers of arguments.
Implement this support in glibc. This change is only for C; C++ would
need a separate change to its separate assert implementations. It's
also applied only in C23 mode. It depends on support for (C99)
variadic macros, and also (in order to detect calls where more than
one expression is passed, via an unevaluated function call) a C99
boolean type. These requirements are encapsulated in the definition
of __ASSERT_VARIADIC. Tests with -std=c99 and -std=gnu99 (using
implementations continue to work.
I don't think we have a way in the glibc testsuite to validate that
passing more than one expression as an argument does produce the
desired error.
The Dynamic Linker chapter now includes a new section detailing
environment variables that influence its behavior.
This new section documents the `LD_DEBUG` environment variable,
explaining how to enable debugging output and listing its various
keywords like `libs`, `reloc`, `files`, `symbols`, `bindings`,
`versions`, `scopes`, `tls`, `all`, `statistics`, `unused`, and `help`.
It also documents `LD_DEBUG_OUTPUT`, which controls where the debug
output is written, allowing redirection to a file with the process ID
appended.
This provides users with essential information for controlling and
debugging the dynamic linker.
Introduce the `DL_DEBUG_TLS` debug mask to enable detailed logging for
Thread-Local Storage (TLS) and Thread Control Block (TCB) management.
This change integrates a new `tls` option into the `LD_DEBUG`
environment variable, allowing developers to trace:
- TCB allocation, deallocation, and reuse events in `dl-tls.c`,
`nptl/allocatestack.c`, and `nptl/nptl-stack.c`.
- Thread startup events, including the TID and TCB address, in
`nptl/pthread_create.c`.
A new test, `tst-dl-debug-tid`, has been added to validate the
functionality of this new debug logging, ensuring that relevant messages
are correctly generated for both main and worker threads.
This enhances the debugging capabilities for diagnosing issues related
to TLS allocation and thread lifecycle within the dynamic linker.
Pincheng Wang [Fri, 31 Oct 2025 20:15:26 +0000 (15:15 -0500)]
riscv: Add Zbkb optimized repeat_bytes helper
Introduce a RISC-V specific string-misc.h to provide an optimized
repeat_bytes implementation when the Zbkb extension is available.
The new version uses packh/packw/pack instruction count and avoiding
high latency instructions. This helper is used by several mem and string
functions, and falls back to the generic implementation when Zbkb is not
present.
Signed-off-by: Pincheng Wang <pincheng.plct@isrc.iscas.ac.cn> Reviewed-by: Peter Bergner <bergner@tenstorrent.com>
Wilco Dijkstra [Fri, 24 Oct 2025 14:26:50 +0000 (14:26 +0000)]
math: Fix powf special case [BZ #33563]
Fix powf (0x1.fffffep+127, 1.0f) to return 0x1.fffffep+127 when
rouding upwards. Cleanup the special case code - performance
improves by ~1.2%. This fixes BZ #33563.
Yury Khrustalev [Wed, 29 Oct 2025 15:59:53 +0000 (15:59 +0000)]
debug: mark __libc_message_wrapper as always inline
When building with -Og to enable debugging, there is currently a compiler error
because if __libc_message_wrapper() is not inline, the __va_arg_pack_len macro
cannot be used.
Eric Wong [Fri, 31 Oct 2025 03:03:00 +0000 (20:03 -0700)]
cdefs: allow __attribute__ on tcc
According to the tcc (tiny C compiler) Changelog, tcc supports
__attribute__ since 0.9.3. Looking at history of tcc at
<https://repo.or.cz/tinycc.git>, __attribute__ support was added
in commit 14658993425878be300aae2e879560698e0c6c4c on 2002-01-03,
which also looks like the release of 0.9.3. While I'm unable to
find release tags for tcc before 0.9.18 (2003-04-14), the next
release (0.9.28) will include __attribute__((cleanup(func)) which
I rely on.
Semantics are unchanged: both read *(a5_old), write *(a3_old), and then
increment a3/a5 by SZREG. memcpy assumes non-overlapping regions, so the
reordering preserves correctness.
No functional change.
Signed-off-by: Yao Zihong <zihong.plct@isrc.iscas.ac.cn> Reviewed-by: Peter Bergner <bergner@tenstorrent.com>
because SZREG and BLOCK_SIZE are powers of two in this context, making the
surrounding addi steps cancel out. Folding to one instruction reduces code
size with identical semantics.
No functional change.
sysdeps/riscv/multiarch/memcpy_noalignment.S: Remove redundant addi around
alignment; keep a single andi for SZREG/BLOCK_SIZE rounding.
Signed-off-by: Yao Zihong <zihong.plct@isrc.iscas.ac.cn> Reviewed-by: Peter Bergner <bergner@tenstorrent.com>
Yao Zihong [Thu, 30 Oct 2025 22:44:07 +0000 (17:44 -0500)]
riscv: memcpy_noalignment: Make register allocation Zca-friendly
Tidy the temporary register allocation to favor registers eligible for
compressed encodings when Zca/Zcb are enabled. This keeps the ABI and
clobber set unchanged and does not alter control flow or memory access
behavior.
No functional change.
sysdeps/riscv/multiarch/memcpy_noalignment.S: Reassign temps to improve
compressed encoding opportunities.
Signed-off-by: Yao Zihong <zihong.plct@isrc.iscas.ac.cn> Reviewed-by: Peter Bergner <bergner@tenstorrent.com>
The optimized i386 version is faster than the generic one, and gcc
implements it through the builtin. It allows us to move the
implementation to a C one.
The optimized i386 version is faster than the generic one, and gcc
implements it through the builtin. It allows us to move the
implementation to a C one. The performance on a Zen3 chip is
similar to the SVID one.
Jiamei Xie [Tue, 14 Oct 2025 12:14:11 +0000 (20:14 +0800)]
x86: fix wmemset ifunc stray '!' (bug 33542)
The ifunc selector for wmemset had a stray '!' in the
X86_ISA_CPU_FEATURES_ARCH_P(...) check:
if (X86_ISA_CPU_FEATURE_USABLE_P (cpu_features, AVX2)
&& X86_ISA_CPU_FEATURES_ARCH_P (cpu_features,
AVX_Fast_Unaligned_Load, !))
This effectively negated the predicate and caused the AVX2/AVX512
paths to be skipped, making the dispatcher fall back to the SSE2
implementation even on CPUs where AVX2/AVX512 are available. The
regression leads to noticeable throughput loss for wmemset.
Remove the stray '!' so the AVX_Fast_Unaligned_Load capability is
tested as intended and the correct AVX2/EVEX variants are selected.
Impact:
- On AVX2/AVX512-capable x86_64, wmemset no longer incorrectly
falls back to SSE2; perf now shows __wmemset_evex/avx2 variants.
Testing:
- benchtests/bench-wmemset shows improved bandwidth across sizes.
- perf confirm the selected symbol is no longer SSE2.
Recent lld version default to --no-undefined-version, which triggers
errors when building multiple libraries. For ld.so on x86_64 it fails
with:
ld.lld: error: version script assignment of 'GLIBC_2.4' to symbol '__stack_chk_guard' failed: symbol not defined
ld.lld: error: version script assignment of 'GLIBC_PRIVATE' to symbol '__nptl_set_robust_list_avail' failed: symbol not defined
ld.lld: error: version script assignment of 'GLIBC_PRIVATE' to symbol '__pointer_chk_guard' failed: symbol not defined
ld.lld: error: version script assignment of 'GLIBC_PRIVATE' to symbol '_dl_starting_up' failed: symbol not defined
While for libc.so:
ld.lld: error: version script assignment of 'GLIBC_2.17' to symbol '_IO_clearerr' failed: symbol not defined
ld.lld: error: version script assignment of 'GLIBC_2.17' to symbol '_IO_fgetc' failed: symbol not defined
ld.lld: error: version script assignment of 'GLIBC_2.17' to symbol '_IO_fileno' failed: symbol not defined
ld.lld: error: version script assignment of 'GLIBC_2.17' to symbol '_IO_freopen' failed: symbol not defined
ld.lld: error: version script assignment of 'GLIBC_2.17' to symbol '_IO_fscanf' failed: symbol not defined
ld.lld: error: version script assignment of 'GLIBC_2.17' to symbol '_IO_fseek' failed: symbol not defined
ld.lld: error: version script assignment of 'GLIBC_2.17' to symbol '_IO_peekc_unlocked' failed: symbol not defined
ld.lld: error: version script assignment of 'GLIBC_2.17' to symbol '_IO_stderr_' failed: symbol not defined
ld.lld: error: version script assignment of 'GLIBC_2.17' to symbol '_IO_stdin_' failed: symbol not defined
ld.lld: error: version script assignment of 'GLIBC_2.17' to symbol '_IO_stdout_' failed: symbol not defined
ld.lld: error: version script assignment of 'GLIBC_2.17' to symbol '_IO_pclose' failed: symbol not defined
ld.lld: error: version script assignment of 'GLIBC_2.17' to symbol '_IO_perror' failed: symbol not defined
ld.lld: error: version script assignment of 'GLIBC_2.17' to symbol '_IO_rewind' failed: symbol not defined
ld.lld: error: version script assignment of 'GLIBC_2.17' to symbol '_IO_scanf' failed: symbol not defined
ld.lld: error: version script assignment of 'GLIBC_2.17' to symbol '_IO_setbuf' failed: symbol not defined
ld.lld: error: version script assignment of 'GLIBC_2.17' to symbol '_IO_setlinebuf' failed: symbol not defined
ld.lld: error: version script assignment of 'GLIBC_2.17' to symbol '_IO_wdefault_setbuf' failed: symbol not defined
ld.lld: error: version script assignment of 'GLIBC_2.17' to symbol '_IO_wfile_setbuf' failed: symbol not defined
ld.lld: error: version script assignment of 'GLIBC_2.17' to symbol '__ctype32_tolower' failed: symbol not defined
ld.lld: error: version script assignment of 'GLIBC_2.17' to symbol '__ctype32_toupper' failed: symbol not defined
ld.lld: error: too many errors emitted, stopping now (use --error-limit=0 to see all errors)
The version script is created with multiple missing symbols to simplify
the build for multiple ABIs, each of which may have different symbols.
For instance, __stack_chk_guard is defined by default. This avoids
requiring each ABI to add this symbol to its version script, depending
on the stack protector ABI it uses.
The libc.so warnings do show unused symbols being defined (like
_IO_clearerr), which might trigger potential errors depending on how
symbols are exported. However, since we already have ABI checks for
missing and extra symbols, the linker's extra checks are not really
necessary.
The --no-undefined-version is the default for ld.bfd.
Supress unused command arguments warning with clang
clang 20 issues an warning for the unused '-c' argument used to create
errlist-data-aux-shared.S, errlist-data-aux.S, siglist-aux-shared.S,
and siglist-aux.S. Filter out the '-c' from the $(compile-command.c).
The clang default to warning for missing fall-through and it does
not support all comment-like annotation that gcc does. Use C23
[[fallthrough]] annotation instead.
proper attribute instead.
argp: Expand argp_usage, _option_is_short, and _option_is_end
The argp code uses macro redefinitions to avoid duplicating static inline
implementations for argp_usage, _option_is_short, and _option_is_end.
However, this causes build issues with clang, as some function prototypes
are redefined to add the hidden attribute with libc_hidden_proto.
To avoid extensive changes to internal headers, just expand the function
implementations and avoid the macro redefine tricks.
The main change is to proper support clang by using builtins. It
fixes a sprof build issue, where previous version uses the generic
code path when building with clang:
sprof.c:682:8: error: result of comparison of constant 288230376151711743 with expression of type 'Elf64_Half' (aka 'unsigned short') is always false [-Werror,-Wtautological-constant-out-of-range-compare]
682 | if (INT_MULTIPLY_WRAPV (ehdr2.e_shnum, sizeof (ElfW(Shdr)), &size))
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
../include/intprops.h:415:34: note: expanded from macro 'INT_MULTIPLY_WRAPV'
415 | _GL_INT_OP_WRAPV (a, b, r, *, _GL_INT_MULTIPLY_RANGE_OVERFLOW)
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
../include/intprops.h:504:45: note: expanded from macro '_GL_INT_OP_WRAPV'
504 | : _GL_INT_OP_WRAPV_LONGISH(a, b, r, op, overflow))
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~
../include/intprops.h:511:41: note: expanded from macro '_GL_INT_OP_WRAPV_LONGISH'
511 | : _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned long int, \
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
512 | unsigned long int, 0, ULONG_MAX)) \
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
../include/intprops.h:533:4: note: expanded from macro '_GL_INT_OP_CALC'
533 | (overflow (a, b, tmin, tmax) \
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~
../include/intprops.h:608:22: note: expanded from macro '_GL_INT_MULTIPLY_RANGE_OVERFLOW'
608 | : (tmax) / (b) < (a)))
| ~~~~~~~~~~~~ ^ ~~~
1 error generated.
H.J. Lu [Mon, 15 Sep 2025 18:24:22 +0000 (11:24 -0700)]
Build programs in $(others-noinstall) like tests
Programs in $(others-noinstall) are internal to glibc build and they
aren't installed. They should be treated like programs in $(others),
but linked like tests so that --enable-hardcoded-path-in-tests also
applies to them.
Also replace run-via-rtld-prefix with test-via-rtld-prefix when running
container tests.
Signed-off-by: H.J. Lu <hjl.tools@gmail.com> Reviewed-by: DJ Delorie <dj@redhat.com>
Osama Abdelkader [Tue, 28 Oct 2025 20:58:35 +0000 (23:58 +0300)]
Fix incorrect setrlimit return value checks in tests
The setrlimit(2) function returns 0 on success and -1 on error, but
several test files were incorrectly checking for a return value of 1
to detect errors. This means the error checks would never trigger,
causing tests to continue silently even when setrlimit() failed.
This commit fixes the error checks in five files to correctly test
for -1, matching both the documented behavior and the pattern used
correctly in other parts of the codebase.
Joseph Myers [Tue, 28 Oct 2025 12:15:02 +0000 (12:15 +0000)]
Rename uimaxabs to umaxabs (bug 33325)
The C2y function uimaxabs has been renamed to umaxabs. Implement this
change in glibc, keeping a compat symbol under the old name, copying
the test to test the new name and changing the old test to test the
compat symbol. Jakub has done the corresponding change to the
built-in function in GCC.
The current implementation precision shows the following accuracy, on
three ranges ([-DBL_MAX,5], [-5,5], [5,DBL_MAX]) with 10e9 uniform
randomly generated numbers for each range (first column is the
accuracy in ULP, with '0' being correctly rounded, second is the
number of samples with the corresponding precision):
The CORE-MATH implementation is correctly rounded for any rounding mode.
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) shows:
The current implementation precision shows the following accuracy, on
three rangeis ([-DBL_MIN, -4.2], [-4.2, 4.2], [4.2, DBL_MAX]) with
10e9 uniform randomly generated numbers for each range (first column
is the accuracy in ULP, with '0' being correctly rounded, second is the
number of samples with the corresponding precision):
The CORE-MATH implementation is correctly rounded for any rounding mode.
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) shows:
The current implementation precision shows the following accuracy, on
one range ([-20,20]) with 10e9 uniform randomly generated numbers for
each range (first column is the accuracy in ULP, with '0' being
correctly rounded, second is the number of samples with the
corresponding precision):
The CORE-MATH implementation is correctly rounded for any rounding mode.
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) shows:
The current implementation precision shows the following accuracy, on
one range ([-1,1]) with 10e9 uniform randomly generated numbers for
each range (first column is the accuracy in ULP, with '0' being
correctly rounded, second is the number of samples with the
corresponding precision):
The CORE-MATH implementation is correctly rounded for any rounding mode.
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) shows:
The internal data definitions are moved to s_atanh_data.c.
It helps on ABIs that build the implementation multiple times for
ifunc optimizations, like x86_64.
The current implementation precision shows the following accuracy, on
one range ([-1,1]) with 10e9 uniform randomly generated numbers for
each range (first column is the accuracy in ULP, with '0' being
correctly rounded, second is the number of samples with the
corresponding precision):
The CORE-MATH implementation is correctly rounded for any rounding mode.
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) shows:
The current implementation precision shows the following accuracy, on
tthree different ranges ([-DBL_MAX, -10], [-10,10], and [10, DBL_MAX))
with 10e9 uniform randomly generated numbers for each range (first
column is the accuracy in ULP, with '0' being correctly rounded, second
is the number of samples with the corresponding precision):
The CORE-MATH implementation is correctly rounded for any rounding mode.
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) shows:
The current implementation precision shows the following accuracy, on
two different ranges ([1,21) and [21, DBL_MAX)) with 10e9 uniform
randomly generated numbers (first column is the accuracy in ULP, with
'0' being correctly rounded, second is the number of samples with the
corresponding precision):
The CORE-MATH implementation is correctly rounded for any rounding mode.
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) shows:
litenglong [Fri, 17 Oct 2025 01:45:41 +0000 (09:45 +0800)]
x86: Disable AVX Fast Unaligned Load on Hygon 1/2/3
- Performance testing revealed significant memcpy performance degradation
when bit_arch_AVX_Fast_Unaligned_Load is enabled on Hygon 3.
- Hygon confirmed AVX performance issues in certain memory functions.
- Glibc benchmarks show SSE outperforms AVX for
memcpy/memmove/memset/strcmp/strcpy/strlen and so on.
- Hardware differences primarily in floating-point operations don't justify
AVX usage for memory operations.
Reviewed-by: gaoxiang <gaoxiang@kylinos.cn> Signed-off-by: litenglong <litenglong@kylinos.cn> Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
Dev Jain [Fri, 24 Oct 2025 16:52:21 +0000 (16:52 +0000)]
malloc: fix large tcache code to check for exact size match
The tcache is used for allocation only if an exact match is found. In the
large tcache code added in commit cbfd7988107b, we currently extract a
chunk of size greater than or equal to the size we need, but don't check
strict equality. This patch fixes that behaviour.
Paul Zimmermann [Tue, 14 Oct 2025 07:58:20 +0000 (09:58 +0200)]
various fixes detected with -Wdouble-promotion
Changes with respect to v1:
- added comment in e_j1f.c to explain the use of float is enough Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
H.J. Lu [Tue, 21 Oct 2025 23:29:03 +0000 (07:29 +0800)]
plot_strings.py: Replace np.complex with complex
Replace np.complex with complex to fix numpy error:
AttributeError: module 'numpy' has no attribute 'complex'.
`np.complex` was a deprecated alias for the builtin `complex`. To avoid this error in existing code, use `complex` by itself. Doing this will not modify any behavior and is safe. If you specifically wanted the numpy scalar type, use `np.complex128` here.
The aliases was originally deprecated in NumPy 1.20; for more details and guidance see the original release note at:
https://numpy.org/devdocs/release/1.20.0-notes.html#deprecations
Signed-off-by: H.J. Lu <hjl.tools@gmail.com> Reviewed-by: Collin Funk <collin.funk1@gmail.com>
DJ Delorie [Thu, 28 Aug 2025 20:30:30 +0000 (16:30 -0400)]
malloc: avoid need for tcache == NULL checks
Avoid needing to check for tcache == NULL by initializing it
to a dummy read-only tcache structure. This dummy is all zeros,
so logically it is both full (when you want to put) and empty (when
you want to get). Also, there are two dummies, one used for
"not yet initialized" and one for "tunables say we shouldn't have
a tcache".
The net result is twofold:
1. Checks for tcache == NULL may be removed from the fast path.
Whether this makes the fast path faster when tcache is
disabled is TBD, but the normal case is tcache enabled.
2. no memory for tcache is allocated if tunables disable caching.
Simplify powl computation for small integral y [BZ #33411]
The powl implementation for x86_64 ends up multiplying X once more than
necessary and then throwing away that result. This results in an
overflow flag being set in cases where there is no overflow.
Simplify the relevant portion by special casing the -3 to 3 range and
simply multiplying repetitively.
rtime.c:96:36: error: variable 'thetime' is uninitialized when passed as a const pointer argument here
[-Werror,-Wuninitialized-const-pointer]
96 | res = __sendto (s, (char *) &thetime, sizeof (thetime), 0,
| ^~~~~~~
For SOCK_DGRAM the sendto sends an uninitialized value.
To use the fabs function to the used type, instead of the double
variant. it fixes a build issue with clang:
./s_compoundn_template.c:64:14: error: absolute value function 'fabs' given an argument of type 'const long double' but has parameter of type 'double' which may cause truncation of value [-Werror,-Wabsolute-value]
64 | FLOAT pd = fabs (*(const FLOAT *) p);
| ^
./s_compoundn_template.c:64:14: note: use function 'fabsl' instead
64 | FLOAT pd = fabs (*(const FLOAT *) p);
| ^~~~
| fabsl
Recent clang version optimizes some loops contructions to strlen [1],
which might generate function calls when self-relocation is not
already done (on tunable parsing). Use an out-of-line function
with __attribute_optimization_barrier__ to avoid this.
And although NAME_IFUNC is and alias for NAME, clang still emits
an 'unused function 'name_ifunc' [-Werror,-Wunused-function]'
warning. The static is used to avoid name pollution on static
linkage.
stdio: Fix -Wtautological-constant-out-of-range-compare on clang
clang emits an error while building vfprintf-internal for default
case:
error: result of comparison of constant 255 with expression of type
'char' is always true
[-Werror,-Wtautological-constant-out-of-range-compare]
if (spec <= UCHAR_MAX
The test is indeed not required for default non-wide build.
On ABIs with defined 'char' was unsigned type, clang fails to build
support_process_state.c with:
support_process_state.c:70:21: error: result of comparison of constant -1 with expression of type 'char' is always false [-Werror,-Wtautological-constant-out-of-range-compare]
70 | if (cur_state == -1)
| ~~~~~~~~~ ^ ~~
1 error generated.
math: Suppress clang -Wincompatible-library-redeclaration on s_llround
Clang issues:
../sysdeps/ieee754/dbl-64/s_llround.c:83:30: error: incompatible
redeclaration of library function 'lround'
[-Werror,-Wincompatible-library-redeclaration]
libm_alias_double (__lround, lround)
^
../sysdeps/ieee754/dbl-64/s_llround.c:83:30: note: 'lround' is a builtin
with type 'long (double)'
../sysdeps/ieee754/dbl-64/e_lgamma_r.c:234:29: error: absolute value function 'fabsf'
given an argument of type 'double' but has parameter of type 'float' which may cause \
truncation of value [-Werror,-Wabsolute-value]
It should not matter because the value is 0.0, but using fabs is
simpler than adding a warning suppresion.
math: Suppress clang -Wabsolute-value warning on math_check_force_underflow
clang warns:
../sysdeps/x86/fpu/powl_helper.c:233:3: error: absolute value function
'__builtin_fabsf' given an argument of type 'typeof (res)' (aka 'long
double') but has parameter of type 'float' which may cause truncation of
value [-Werror,-Wabsolute-value]
math_check_force_underflow (res);
^
./math-underflow.h:45:11: note: expanded from macro
'math_check_force_underflow'
if (fabs_tg (force_underflow_tmp) \
^
./math-underflow.h:27:20: note: expanded from macro 'fabs_tg'
#define fabs_tg(x) __MATH_TG ((x), (__typeof (x)) __builtin_fabs, (x))
^
../math/math.h:899:16: note: expanded from macro '__MATH_TG'
float: FUNC ## f ARGS, \
^
<scratch space>:73:1: note: expanded from here
__builtin_fabsf
^
It simplifies the code a bit and avoid the clang warning:
./config.h:12:2: error: #include_next in file found relative to primary
source file or found by absolute path; will search from start of include
path [-Werror,-Winclude-next-absolute-path]
#include_next <config.h>
^
sunrpc: Suppress clang -Wgnu-variable-sized-type-not-at-end warning on struct cmessage
clang issues:
svc_unix.c:318:18: error: field 'cmsg' with variable sized type 'struct cmsghdr' not at the end of a struct or class is a GNU extension [-Werror,-Wgnu-variable-sized-type-not-at-end]
318 | struct cmsghdr cmsg;
| ^
The __msgread explicitly expects that 'struct ucred' is after the 'cmsg',
so suppress the warning.