We only need to enable GCS tests on AArch64 targets, however previously
the configure checks for GCS support in compiler and linker were added
for all targets which was not efficient.
To enable tests for GCS we need 4 things to be true:
- Compiler supports GCS branch protection.
- Test compiler supports GCS branch protection.
- Linker supports GCS marking of binaries.
- The CRT objects provided by the toolchain have GCS marking.
To check for the latter, we add new macro to aclocal.m4 that allows to
grep output from readelf.
We check all four and then put the result in one make variable to
simplify checks in makefiles.
Reviewed-by: Wilco Dijkstra <Wilco.Dijkstra@arm.com>
Although binutils has supported --no-undefined-version for a long timei
(319416359200 back in 2002), --undefined-version was only added more
recently (27fb6a1a7fcd on 2.40).
Reviewed-by: Sam James <sam@gentoo.org>
The check was initially used to define HAVE_BUILTIN_REDIRECTION, which
enables or not libc_hidden_builtin_proto support. It was later removed
with 3ce1f29594, making the feature
mandatory. The configure check was kept as a transition knob.
Current minimum gcc/linker always supports this, as well as clang with
some extra care. Also, missing hidden_proto/hidden_def support is
already flagged in the check-localplt test.
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
The 53807741fb added a configure check
for 64-bit atomic operations that were not previously enabled on some
32-bit ABIs.
However, the NPTL semaphore code casts a sem_t to a new_sem and issues
a 64-bit atomic operation for __HAVE_64B_ATOMICS. Since sem_t has
32-bit alignment on 32-bit architectures, this prevents the use of
64-bit atomics even if the ABI supports them.
Assume 64-bit atomic support from __WORDSIZE, which maps to how glibc
defines it before the broken change. Also rename __HAVE_64B_ATOMICS
to USE_64B_ATOMICS to define better the flag meaning.
Checked on x86_64-linux-gnu and i686-linux-gnu.
Reviewed-by: Wilco Dijkstra <Wilco.Dijkstra@arm.com>
clang might generate an abort call when cleanup functions (set by
__attribute__ ((cleanup)) calls functions not marked as nothrow.
The hurd already provides abort for the loader at
sysdeps/mach/hurd/dl-sysdep.c, and adding it rtld-stubbed-symbols
triggers duplicate symbols.
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
Some symbols that might be auto-generated by the compiler are redefined
to internal alias (for instance mempcpy to __mempcpy). However, if fortify
is enabled, the fortify wrapper is define before the alias re-defined and
clang warns attribute declaration must precede definition.
Use an asm alias if compiler does not support it, instead of an
attribute.
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
Now that atomic builtins are used by default, we can rely on the
compiler to define when to use 64-bit atomic operations.
It allows the use of 64-bit atomic operations on some 32-bit ABIs where
they were not previously enabled due to missing pre-processor handling:
hppa, mips64n32, s390, and sparcv9.
Co-authored-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Reviewed-by: Uros Bizjak <ubizjak@gmail.com>
Reviewed-by: Wilco Dijkstra <Wilco.Dijkstra@arm.com>
The configure check always fail with clang:
conftest.c:5:58: error: expected string literal as argument of 'alias' attribute
5 | extern __typeof (__foo) foo __attribute__ ((weak, alias (__foo)));
| ^
conftest.c:6:58: error: expected string literal as argument of 'alias' attribute
6 | extern __typeof (__foo) bar __attribute__ ((weak, alias (foo)));
| ^
Reviewed-by: Sam James <sam@gentoo.org>
LIBC_TRY_TEST_CC_OPTION is defined with LIBC_TRY_CC_OPTION:
dnl Test a compiler option or options with an empty input file.
dnl LIBC_TRY_CC_OPTION([options], [action-if-true], [action-if-false])
AC_DEFUN([LIBC_TRY_CC_OPTION],
[AS_IF([AC_TRY_COMMAND([${CC-cc} $1 -xc /dev/null -S -o /dev/null])],
[$2], [$3])])
which passes -S to compiler. Unlike gcc, when -c is also passed to clang
20, we get
configure:7838: clang -c -Werror -fsemantic-interposition -xc /dev/null -S -o /dev/null
clang: error: argument unused during compilation: '-c' [-Werror,-Wunused-command-line-argument]
Don't pass -c to LIBC_TRY_TEST_CC_OPTION since -c isn't needed.
This fixes BZ #33318.
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Reviewed-by: Sam James <sam@gentoo.org>
Since have-mamx-tile is for TEST_CC only as shown in
sysdeps/x86_64/configure.ac:
LIBC_CONFIG_VAR([have-mamx-tile], [$libc_cv_test_x86_have_amx_tile])
remove test-have-mamx-tile from Makefile.in.
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Reviewed-by: Sam James <sam@gentoo.org>
Don't use -Wfree-labels/-Wmissing-parameter-name for "make check" if
they are unsupported by TEST_CC.
This fixes BZ #33310.
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Reviewed-by: Collin Funk <collin.funk1@gmail.com>
Clang's -Wimplicit-fallthrough warning, which flags unannotated
fall-through in switch statements, does not recognize specific comments
like /* FALLTHROUGH */ for suppressing the warning, unlike GCC. Since
fall through comments are used extensively in glibc, disable
-Wimplicit-fallthrough when clang is in use.
This fixes BZ #33312.
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Reviewed-by: Collin Funk <collin.funk1@gmail.com>
And add extra checks to enable for binutils 2.45 and if the architecture
explicitly enables it. When SFrame is disabled, all the related code
is also not enabled for backtrace() and _dl_find_object(), so SFrame
backtracking is not used even if the binary has the SFrame segment.
This patch also adds some other related fixes:
* Fixed an issue with AC_CHECK_PROG_VER, where the READELF_SFRAME
usage prevented specifying a different readelf through READELF
environment variable at configure time.
* Add an extra arch-specific internal definition,
libc_cv_support_sframe, to disable --enable-sframe on architectures
that have binutils but not glibc support (s390x).
* Renamed the tests without the .sframe segment and move the
tst-backtrace1 from pthread to debug.
* Use the built compiler strip to remove the .sframe segment,
instead of the system one (which might not support SFrame).
Checked on x86_64-linux-gnu and aarch64-linux-gnu.
Reviewed-by: Sam James <sam@gentoo.org>
Enable SFrame stack track information. The --enable-sframe option
allows the glibc build to compile with SFrame stack track
information. Thus, enabling glibc's backtrace to work within glibc.
Signed-off-by: Claudiu Zissulescu <claudiu.zissulescu-ianculescu@oracle.com>
Reviewed-by: DJ Delorie <dj@redhat.com>
Reviewed-by: Sam James <sam@gentoo.org>
Compiler generates the following instruction sequence for dynamic TLS
access:
leal tls_var@tlsgd(,%ebx,1), %eax
call ___tls_get_addr@PLT
CALL instruction is transparent to compiler which assumes all registers,
except for EFLAGS, AX, CX, and DX, are unchanged after CALL. But
___tls_get_addr is a normal function which doesn't preserve any vector
registers.
1. Rename the generic __tls_get_addr function to ___tls_get_addr_internal.
2. Change ___tls_get_addr to a wrapper function with implementations for
FNSAVE, FXSAVE, XSAVE and XSAVEC to save and restore all vector registers.
3. dl-tlsdesc-dynamic.h has:
_dl_tlsdesc_dynamic:
/* Like all TLS resolvers, preserve call-clobbered registers.
We need two scratch regs anyway. */
subl $32, %esp
cfi_adjust_cfa_offset (32)
It is wrong to use
movl %ebx, -28(%esp)
movl %esp, %ebx
cfi_def_cfa_register(%ebx)
...
mov %ebx, %esp
cfi_def_cfa_register(%esp)
movl -28(%esp), %ebx
to preserve EBX on stack. Fix it with:
movl %ebx, 28(%esp)
movl %esp, %ebx
cfi_def_cfa_register(%ebx)
...
mov %ebx, %esp
cfi_def_cfa_register(%esp)
movl 28(%esp), %ebx
4. Update _dl_tlsdesc_dynamic to call ___tls_get_addr_internal directly.
5. Add have-test-mtls-traditional to compile tst-tls23-mod.c with
traditional TLS variant to verify the fix.
6. Define DL_RUNTIME_RESOLVE_REALIGN_STACK in sysdeps/x86/sysdep.h.
This fixes BZ #32996.
Co-Authored-By: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
The recent commit 27b96e069a raises the minimum
GCC version to 12.1 which was released in 2022.
The current minimum bintuils version 2.25 was released end of 2014. This patch
now raises the minimum binutils version to 2.39 which was also released in 2022.
The hint for ARC is not needed anymore.
In sysdeps/[alpha|hppa|csky]/configure.ac, PIE is unsupported with this comment:
PIE builds fail on binutils 2.37 and earlier, see:
https://sourceware.org/bugzilla/show_bug.cgi?id=28672
This patch keeps PIE unsupported and let the machine maintainers test and
enable it later.
In sysdeps/arm/configure.ac, there is a check whether TPOFF relocs with addends
are assembled correctly, which is known to be broken in binutils 2.24 and 2.25.
See: https://sourceware.org/bugzilla/show_bug.cgi?id=18383
This patch keeps the check as is and let the machine maintainers check if it
still required.
According to Florian Weimer:
Having at least binutils 2.38 will allow us to assume that this linker
bug is fixed:
Bug 28743 - -z relro creats holes in the process image on GNU/Linux
<https://sourceware.org/bugzilla/show_bug.cgi?id=28743>
Reviewed-by: Florian Weimer <fweimer@redhat.com>
Add a configure check to detect bootstrapping builds that do not
have libgcc_s.
Fixes commit 3e2be87832 ("support: Link
links-dso-program-c against libgcc_s").
Reviewed-by: Sam James <sam@gentoo.org>
BFD ld recognizes all -no-* options (with a single leading dash)
unconditionally.
Fixes commit a2bd5008a9
("Pass -Wl,--no-error-execstack for tests where -Wl,-z,execstack
is used [PR32717]").
The BZ #32763 tests fail to build for MicroBlaze (which defines
MAX_OFILE_ALIGNMENT to (32768*8) in GCC, so __attribute__ ((aligned
(65536))) is unsupported). Add a configure-time check to enable BZ #32763
tests only if __attribute__ ((aligned (65536))) is supported.
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Reviewed-by: Sam James <sam@gentoo.org>
When GNU Binutils is configured with --enable-error-execstack=yes, a handful
of our tests which rely on -Wl,-z,execstack fail. Pass --Wl,--no-error-execstack
to override the behaviour and get a warning instead.
Bug: https://sourceware.org/PR32717
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
- Add check that linker supports -z gcs=...
- Add checks that main and test compiler support
-mbranch-protection=gcs
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Clear libc_cv_cc_wimplicit_fallthrough if -Wimplicit-fallthrough isn't
supported. Tested with GCC 6.4.1 on x86-64.
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Reviewed-by: Sam James <sam@gentoo.org>
Since have-mtls-descriptor is only used for glibc testing, rename it to
have-test-mtls-descriptor. Also enable tst-gnu2-tls2-amx only if
$(have-test-mtls-descriptor) == gnu2.
Tested with GCC 14 and Clang 19/18/17 on x86-64.
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Reviewed-by: Sam James <sam@gentoo.org>
Change configure output for C++ Compiler from
...
checking -finput-charset=ascii in testing... -finput-charset=ascii
checking -finput-charset=ascii in testing... -finput-charset=ascii
...
to
...
checking -finput-charset=ascii in testing... -finput-charset=ascii
checking g++ -finput-charset=ascii in testing... -finput-charset=ascii
...
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Reviewed-by: Sam James <sam@gentoo.org>
Add a configure check for -Wno-fortify-source to suppress Clang warnings
on string/tester.c, like:
tester.c:385:10: error: 'strncat' size argument is too large; destination buffer has size 50, but size argument is 99 [-Werror,-Wfortify-source]
385 | check (strncat (one, "lmn", 99) == one, 1); /* Returned value. */
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Reviewed-by: Sam James <sam@gentoo.org>
Check if TEST_CC supports -Wno-restrict before using it to avoid Clang
error:
error: unknown warning option '-Wno-restrict' [-Werror,-Wunknown-warning-option]
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Reviewed-by: Sam James <sam@gentoo.org>
tst-dlopen-nodelete-reloc requires STB_GNU_UNIQUE support so that NODELETE
is propagated by do_lookup_unique. Enable it only if TEST_CXX supports
STB_GNU_UNIQUE,
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Reviewed-by: Sam James <sam@gentoo.org>
Check PDE load address with non-empty text section:
.globl _start
_start:
.globl __start
.byte 0
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Reviewed-by: Sam James <sam@gentoo.org>
Compiler may default to -fno-semantic-interposition. But some elf test
modules must be compiled with -fsemantic-interposition to function properly.
Add a TEST_CC check for -fsemantic-interposition and use it on elf test
modules. This fixed
FAIL: elf/tst-dlclose-lazy
FAIL: elf/tst-pie1
FAIL: elf/tst-plt-rewrite1
FAIL: elf/unload4
when Clang 19 is used to test glibc.
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Reviewed-by: Sam James <sam@gentoo.org>
Add include/libc-misc.h to provide miscellaneous definitions for both
glibc build and test:
1. Move inhibit_stack_protector to libc-misc.h and add Clang support.
2. Add test_inhibit_stack_protector for glibc testing.
3. Move inhibit_loop_to_libcall to libc-misc.h.
4. Add test_cc_inhibit_loop_to_libcall to handle TEST_CC != CC and
replace inhibit_loop_to_libcall with test_cc_inhibit_loop_to_libcall
in glibc tests.
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Co-Authored-By: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Reviewed-by: Sam James <sam@gentoo.org>
Clang doesn't support -ffloat-store:
clang: error: optimization flag '-ffloat-store' is not supported [-Werror,-Wignored-optimization-argument]
Define test-config-cflags-float-store for -ffloat-store and use it in
math/Makefile for testing.
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Reviewed-by: Sam James <sam@gentoo.org>
Since trampoline is required to test execstack, enable execstack tests
only if compiler supports trampoline.
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Reviewed-by: Sam James <sam@gentoo.org>
Check if -finput-charset=ascii is supported before using it in
check-installed-headers.sh.
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>
Since the C++ compiler is also used to compile links-dso-program.cc in
libsupport, use TEST_CXX to get C++ headers for testing, but don't use
TEST_CXX as CXX for build.
Tested for m68k-linux-gnu-coldfire build and native build on x86-64.
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Reviewed-by: Sam James <sam@gentoo.org>
Since the C++ compiler is used only for testing, use TEST_CXX as the C++
compiler if available. If C++ link test fails, clear both CXX and
TEST_CXX so that the C++ compiler isn't used for glibc build nor test.
Tested for m68k-linux-gnu-coldfire build and native build on x86-64.
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Reviewed-by: Sam James <sam@gentoo.org>
Support testing glibc build with a different C compiler or a different
C++ compiler with
$ ../glibc-VERSION/configure TEST_CC="gcc-6.4.1" TEST_CXX="g++-6.4.1"
1. Add LIBC_TRY_CC_AND_TEST_CC_OPTION, LIBC_TRY_CC_AND_TEST_CC_COMMAND
and LIBC_TRY_CC_AND_TEST_LINK to test both CC and TEST_CC.
2. Add check and xcheck targets to Makefile.in and override build compiler
options with ones from TEST_CC and TEST_CXX.
Tested on Fedora 41/x86-64:
1. Building with GCC 14.2.1 and testing with GCC 6.4.1 and GCC 11.2.1.
2. Building with GCC 15 and testing with GCC 6.4.1.
Support for GCC versions older than GCC 6.2 may need to change the test
sources. Other targets may need to update configure.ac under sysdeps and
modify Makefile.in to override target build compiler options.
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Reviewed-by: Sam James <sam@gentoo.org>
Remove
AC_SUBST(libc_cv_mtls_descriptor)
since there is no @libc_cv_mtls_descriptor@ and there is
LIBC_CONFIG_VAR([have-mtls-descriptor], [$libc_cv_mtls_descriptor])
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Reviewed-by: Sam James <sam@gentoo.org>
For a static PIE with non-zero load address, its PT_DYNAMIC segment
entries contain the relocated values for the load address in static PIE.
Since static PIE usually doesn't have PT_PHDR segment, use p_vaddr of
the PT_LOAD segment with offset == 0 as the load address in static PIE
and adjust the entries of PT_DYNAMIC segment in static PIE by properly
setting the l_addr field for static PIE. This fixes BZ #31799.
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
Even though building glibc with 64 bit time_t flags is not supported,
and the usual way is to patch the build system to avoid it; some
systems do enable it by default, and it increases the requirements
to build glibc in such cases (it also does not help newcomers when
trying to build glibc).
The conform namespace and linknamespace tests also do not expect
that flag to be set by default, so disable it as well.
Checked with a build/check for major ABI and some (i386, arm,
mipsel, hppa) with a toolchain that has LFS flags by default.
Reviewed-by: DJ Delorie <dj@redhat.com>
Even though building glibc with LFS flags is not supported, and the
the usual way is to patch the build system to avoid it [1]; some system
do enable it by default, and it increases the requirements to build
glibc in such cases (it also does not help newcomers when trying
to build glibc).
The conform namespace and linknamespace tests also do not expect
that flag to be set by default, so disable it as well.
Checked with a build/check for major ABI and some (i386, arm,
mipsel, hppa) with a toolchain that has LFS flags by default.
[1] https://sourceware.org/bugzilla/show_bug.cgi?id=31624
Reviewed-by: DJ Delorie <dj@redhat.com>
Yury Khrustalev
Adhemerval Zanella
Wilco Dijkstra
H.J. Lu
Sam James
Claudiu Zissulescu
Florian Weimer
Stefan Liebler
Dmitry Chestnykh