aboutsummaryrefslogtreecommitdiff
path: root/include/libc-symbols.h
AgeCommit message (Collapse)Author
2022-05-13Add declare_object_symbol_alias for assembly codes (BZ #28128)H.J. Lu
There are 2 problems in: #define declare_symbol_alias(symbol, original, type, size) \ declare_symbol_alias_1 (symbol, original, type, size) #ifdef __ASSEMBLER__ # define declare_symbol_alias_1(symbol, original, type, size) \ strong_alias (original, symbol); \ .type C_SYMBOL_NAME (symbol), %##type; \ .size C_SYMBOL_NAME (symbol), size 1. .type and .size are substituted by arguments. 2. %##type is expanded to "% type" due to the GCC bug: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101613 But assembler doesn't support "% type". Workaround BZ #28128 by 1. Don't define declare_symbol_alias for assembly codes. 2. Define declare_object_symbol_alias for assembly codes. Reviewed-by: Fangrui Song <maskray@google.com>
2022-01-01Update copyright dates with scripts/update-copyrightsPaul Eggert
I used these shell commands: ../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright (cd ../glibc && git commit -am"[this commit message]") and then ignored the output, which consisted lines saying "FOO: warning: copyright statement not found" for each of 7061 files FOO. I then removed trailing white space from math/tgmath.h, support/tst-support-open-dev-null-range.c, and sysdeps/x86_64/multiarch/strlen-vec.S, to work around the following obscure pre-commit check failure diagnostics from Savannah. I don't know why I run into these diagnostics whereas others evidently do not. remote: *** 912-#endif remote: *** 913: remote: *** 914- remote: *** error: lines with trailing whitespace found ... remote: *** error: sysdeps/unix/sysv/linux/statx_cp.c: trailing lines
2021-07-07nss_files: Move into libcFlorian Weimer
This is the first step towards fixing bug 27959. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2021-04-16Set the retain attribute on _elf_set_element if CC supports [BZ #27492]Fangrui Song
So that text_set_element/data_set_element/bss_set_element defined variables will be retained by the linker. Note: 'used' and 'retain' are orthogonal: 'used' makes sure the variable will not be optimized out; 'retain' prevents section garbage collection if the linker support SHF_GNU_RETAIN. GNU ld 2.37 and LLD 13 will support -z start-stop-gc which allow C identifier name sections to be GCed even if there are live __start_/__stop_ references. Without the change, there are some static linking problems, e.g. _IO_cleanup (libio/genops.c) may be discarded by ld --gc-sections, so stdout is not flushed on exit. Note: GCC may warning 'retain' attribute ignored while __has_attribute(retain) is 1 (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99587). Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
2021-03-25Support for multiple versions in versioned_symbol, compat_symbolFlorian Weimer
This essentially folds compat_symbol_unique functionality into compat_symbol. This change eliminates the need for intermediate aliases for defining multiple symbol versions, for both compat_symbol and versioned_symbol. Some binutils versions do not suport multiple versions per symbol on some targets, so aliases are automatically introduced, similar to what compat_symbol_unique did. To reduce symbol table sizes, a configure check is added to avoid these aliases if they are not needed. The new mechanism works with data symbols as well as function symbols, due to the way an assembler-level redirect is used. It is not compatible with weak symbols for old binutils versions, which is why the definition of __malloc_initialize_hook had to be changed. This is not a loss of functionality because weak symbols do not matter to dynamic linking. The placeholder symbol needs repeating in nptl/libpthread-compat.c now that compat_symbol is used, but that seems more obvious than introducing yet another macro. A subtle difference was that compat_symbol_unique made the symbol global automatically. compat_symbol does not do this, so static had to be removed from the definition of __libpthread_version_placeholder. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2021-03-25Change how the symbol_version_reference macro is definedFlorian Weimer
A subsequent change will require including <config.h> for defining symbol_version_reference. <libc-symbol.h> should not include <config.h> for _ISOMAC, so it cannot define symbol_version_reference anymore, but symbol_version_reference is needed <shlib-compat.h> even for _ISOMAC. Moving the definition of symbol_version_reference to a separate file <libc-symver.h> makes it possible to use a single definition for both cases. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2021-03-09<shlib-compat.h>: Support compat_symbol_reference for _ISOMACFlorian Weimer
This is helpful for testing compat symbols in cases where _ISOMAC is activated implicitly due to -DMODULE_NAME=testsuite and cannot be disabled easily.
2021-01-27Revert "Make libc symbols hidden in static PIE" [BZ #27237]Szabolcs Nagy
This reverts commit 2682695e5c7acf1e60dd3b5c3a14d4e82416262c. Fixes bug 27237. That commit turned out to be too intrusive affecting crt files, test system and benchmark files. They should not be affected, but the build system does not set the MODULE_NAME and LIBC_NONSHARED reliably.
2021-01-21Make libc symbols hidden in static PIESzabolcs Nagy
Hidden visibility can avoid indirections and RELATIVE relocs in static PIE libc. The check should use IS_IN_LIB instead of IS_IN(libc) since all symbols are defined locally in static PIE and the optimization is useful in all libraries not just libc. However the test system links objects from libcrypt.a into dynamic linked test binaries where hidden visibility does not work. I think mixing static and shared libc components in the same binary should not be supported usage, but to be safe only use hidden in libc.a. On some targets (i386) this optimization cannot be applied because hidden visibility PIE ifunc functions don't work, so it is gated by NO_HIDDEN_EXTERN_FUNC_IN_PIE. From -static-pie linked 'int main(){}' this shaves off 71 relative relocs on aarch64 and reduces code size by about 2k. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2021-01-02Update copyright dates with scripts/update-copyrightsPaul Eggert
I used these shell commands: ../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright (cd ../glibc && git commit -am"[this commit message]") and then ignored the output, which consisted lines saying "FOO: warning: copyright statement not found" for each of 6694 files FOO. I then removed trailing white space from benchtests/bench-pthread-locks.c and iconvdata/tst-iconv-big5-hkscs-to-2ucs4.c, to work around this diagnostic from Savannah: remote: *** pre-commit check failed ... remote: *** error: lines with trailing whitespace found remote: error: hook declined to update refs/heads/master
2020-12-16Mark __libc_freeres_fn as used [BZ #27002]H.J. Lu
GCC 11 with commit 6fbec038f7a7ddf29f074943611b53210d17c40c Author: H.J. Lu <hjl.tools@gmail.com> Date: Mon Feb 3 11:55:43 2020 -0800 Use SHF_GNU_RETAIN to preserve symbol definitions places used symbols in SECTION_RETAIN sections if assembler supports it. Mark __libc_freeres_fn as used to avoid gconv_dl.c: In function 'free_mem': gconv_dl.c:191:1: error: 'do_release_all' without 'used' attribute and 'free_mem' with 'used' attribute are placed in a section with the same name [-Werror=attributes] 191 | do_release_all (void *nodep) | ^~~~~~~~~~~~~~ In file included from <command-line>: gconv_dl.c:202:18: note: 'free_mem' was declared here 202 | libc_freeres_fn (free_mem) | ^~~~~~~~ ./../include/libc-symbols.h:316:15: note: in definition of macro 'libc_freeres_fn' 316 | static void name (void) | ^~~~ cc1: all warnings being treated as errors
2020-12-04symbols: Add defines for libanl's libanl_hidden_{def|proto}Lukasz Majewski
The __gai_suspend_time64, which supports 64 bit time on ports with __WORDSIZE == 32 && __TIMESIZE != 64, shall be exported from libanl (the same library from which original gai_suspend is exported). Up till now there were no defines for this library. This commit adds them.
2020-11-11hurd: keep only required PLTs in ld.soSamuel Thibault
We need NO_RTLD_HIDDEN because of the need for PLT calls in ld.so. See Roland's comment in https://sourceware.org/bugzilla/show_bug.cgi?id=15605 "in the Hurd it's crucial that calls like __mmap be the libc ones instead of the rtld-local ones after the bootstrap phase, when the dynamic linker is being used for dlopen and the like." We used to just avoid all hidden use in the rtld ; this commit switches to keeping only those that should use PLT calls, i.e. essentially those defined in sysdeps/mach/hurd/dl-sysdep.c: __assert_fail __assert_perror_fail __*stat64 _exit This fixes a few startup issues, notably the call to __tunable_get_val that is made before PLTs are set up.
2020-07-13Remove --enable-obsolete-rpc configure flagPetr Vorel
Sun RPC was removed from glibc. This includes rpcgen program, librpcsvc, and Sun RPC headers. Also test for bug #20790 was removed (test for rpcgen). Backward compatibility for old programs is kept only for architectures and ABIs that have been added in or before version 2.28. libtirpc is mature enough, librpcsvc and rpcgen are provided in rpcsvc-proto project. NOTE: libnsl code depends on Sun RPC (installed libnsl headers use installed Sun RPC headers), thus --enable-obsolete-rpc was a dependency for --enable-obsolete-nsl (removed in a previous commit). The arc ABI list file has to be updated because the port was added with the sunrpc symbols Tested-by: Carlos O'Donell <carlos@redhat.com> Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2020-07-08Remove --enable-obsolete-nsl configure flagPetr Vorel
this means that *always* libnsl is only built as shared library for backward compatibility and the NSS modules libnss_nis and libnss_nisplus are not built at all, libnsl's headers aren't installed. This compatibility is kept only for architectures and ABIs that have been added in or before version 2.28. Replacement implementations based on TIRPC, which additionally support IPv6, are available from <https://github.com/thkukuk/>. This change does not affect libnss_compat which does not depended on libnsl since 2.27 and thus can be used without NIS. libnsl code depends on Sun RPC, e.g. on --enable-obsolete-rpc (installed libnsl headers use installed Sun RPC headers), which will be removed in the following commit.
2020-05-20<libc-symbols.h>: Add libpthread hidden alias supportFlorian Weimer
Reviewed-by: Carlos O'Donell <carlos@redhat.com> Tested-by: Carlos O'Donell <carlos@redhat.com>
2020-03-25ldbl-128ibm-compat: PLT redirects for using ldbl redirects internallyPaul E. Murphy
Tweak the PLT bypass magic when building glibc with long double redirects. This is made more difficult by the fact we only get one chance to redirect functions. This happens via the public headers. There are roughly three classes of redirect we need to attend to today: 1. Simple redirects, redirected via cdef macro overrides and and new libc_hidden_ldbl_proto macro. 2. Internal usage of internal API, e.g __snprintf, which has no direct analogue. This is bypassed directly on case-by- case basis. 3. Double redirects, e.g sscanf and related. These require a heavier handed approach of macro renaming to existing symbols. Most simple redirects are handled via 1. Ideally, the libc_* macro would live in libc-symbols.h, but in practice the macros needed for it to do anything useful live in cdefs.h, so they are defined in the local override. Notably, the internal name of the asprintf generated for ieee ldbl redirects is renamed to work with internal prefixed usage. This resolves the local plt usage introduced when building glibc with ldbl == ieee128 on ppc64le. Reviewed-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>
2020-02-25nss_nis: Use NSS_DECLARE_MODULE_FUNCTIONSFlorian Weimer
This commit removes the minor optimization based on strong aliases because it loses type safety.
2020-02-15ld.so: Do not export free/calloc/malloc/realloc functions [BZ #25486]Florian Weimer
Exporting functions and relying on symbol interposition from libc.so makes the choice of implementation dependent on DT_NEEDED order, which is not what some compiler drivers expect. This commit replaces one magic mechanism (symbol interposition) with another one (preprocessor-/compiler-based redirection). This makes the hand-over from the minimal malloc to the full malloc more explicit. Removing the ABI symbols is backwards-compatible because libc.so is always in scope, and the dynamic loader will find the malloc-related symbols there since commit f0b2132b35248c1f4a80f62a2c38cddcc802aa8c ("ld.so: Support moving versioned symbols between sonames [BZ #24741]"). Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2020-01-01Update copyright dates with scripts/update-copyrights.Joseph Myers
2019-09-07Prefer https to http for gnu.org and fsf.org URLsPaul Eggert
Also, change sources.redhat.com to sourceware.org. This patch was automatically generated by running the following shell script, which uses GNU sed, and which avoids modifying files imported from upstream: sed -ri ' s,(http|ftp)(://(.*\.)?(gnu|fsf|sourceware)\.org($|[^.]|\.[^a-z])),https\2,g s,(http|ftp)(://(.*\.)?)sources\.redhat\.com($|[^.]|\.[^a-z]),https\2sourceware.org\4,g ' \ $(find $(git ls-files) -prune -type f \ ! -name '*.po' \ ! -name 'ChangeLog*' \ ! -path COPYING ! -path COPYING.LIB \ ! -path manual/fdl-1.3.texi ! -path manual/lgpl-2.1.texi \ ! -path manual/texinfo.tex ! -path scripts/config.guess \ ! -path scripts/config.sub ! -path scripts/install-sh \ ! -path scripts/mkinstalldirs ! -path scripts/move-if-change \ ! -path INSTALL ! -path locale/programs/charmap-kw.h \ ! -path po/libc.pot ! -path sysdeps/gnu/errlist.c \ ! '(' -name configure \ -execdir test -f configure.ac -o -f configure.in ';' ')' \ ! '(' -name preconfigure \ -execdir test -f preconfigure.ac ';' ')' \ -print) and then by running 'make dist-prepare' to regenerate files built from the altered files, and then executing the following to cleanup: chmod a+x sysdeps/unix/sysv/linux/riscv/configure # Omit irrelevant whitespace and comment-only changes, # perhaps from a slightly-different Autoconf version. git checkout -f \ sysdeps/csky/configure \ sysdeps/hppa/configure \ sysdeps/riscv/configure \ sysdeps/unix/sysv/linux/csky/configure # Omit changes that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/powerpc/powerpc64/ppc-mcount.S: trailing lines git checkout -f \ sysdeps/powerpc/powerpc64/ppc-mcount.S \ sysdeps/unix/sysv/linux/s390/s390-64/syscall.S # Omit change that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S: last line does not end in newline git checkout -f sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S
2019-01-01Update copyright dates with scripts/update-copyrights.Joseph Myers
* All files with FSF copyright notices: Update copyright dates using scripts/update-copyrights. * locale/programs/charmap-kw.h: Regenerated. * locale/programs/locfile-kw.h: Likewise.
2018-11-13Add hidden_tls_def macros, fix powerpc-soft build with GCC 9.Joseph Myers
Soft-float powerpc fails to build with current GCC mainline because of use of libc_hidden_data_def for TLS variables, resulting in a non-TLS alias being defined, to which the tls_model attribute is now copied, resulting in a warning about it being ignored. The problem here appears to be the non-TLS alias. This patch adds a hidden_tls_def macro family, corresponding to the hidden_tls_proto macros, to define TLS aliases properly in such a case, and uses it for those powerpc soft-float variables. Tested with build-many-glibcs.py compilers build for powerpc-linux-gnu soft-float. Also tested for x86_64. * include/libc-symbols.h [SHARED && !NO_HIDDEN && !__ASSEMBLER__] (__hidden_ver2): New macro. Use old definition of __hidden_ver1 with additional parameter thread. [SHARED && !NO_HIDDEN && !__ASSEMBLER__] (__hidden_ver1): Define in terms of __hidden_ver2. (hidden_tls_def): New macro. (libc_hidden_tls_def): Likewise. (rtld_hidden_tls_def): Likewise. (libm_hidden_tls_def): Likewise. (libmvec_hidden_tls_def): Likewise. (libresolv_hidden_tls_def): Likewise. (librt_hidden_tls_def): Likewise. (libdl_hidden_tls_def): Likewise. (libnss_files_hidden_tls_def): Likewise. (libnsl_hidden_tls_def): Likewise. (libnss_nisplus_hidden_tls_def): Likewise. (libutil_hidden_tls_def): Likewise. (libutil_hidden_tls_def): Likweise. * sysdeps/powerpc/nofpu/sim-full.c (__sim_exceptions_thread): Use libc_hidden_tls_def. (__sim_disabled_exceptions_thread): Likewise. (__sim_round_mode_thread): Likewise.
2018-11-09Add support for GCC 9 attribute copy.Martin Sebor
GCC 9 has gained an enhancement to help detect attribute mismatches between alias declarations and their targets. It consists of a new warning, -Wattribute-alias, an enhancement to an existing warning, -Wmissing-attributes, and a new attribute called copy. The purpose of the warnings is to help identify either possible bugs (an alias declared with more restrictive attributes than its target promises) or optimization or diagnostic opportunities (an alias target missing some attributes that it could be declared with that might benefit analysis and code generation). The purpose of the new attribute is to easily apply (almost) the same set of attributes to one declaration as those already present on another. As expected (and intended) the enhancement triggers warnings for many alias declarations in Glibc code. This change, tested on x86_64-linux, avoids all instances of the new warnings by making use of the attribute where appropriate. To fully benefit from the enhancement Glibc will need to be compiled with -Wattribute-alias=2 and remaining warnings reviewed and dealt with (there are a couple of thousand but most should be straightforward to deal with). ChangeLog: * include/libc-symbols.h (__attribute_copy__): Define macro unless it's already defined. (_strong_alias): Use __attribute_copy__. (_weak_alias, __hidden_ver1, __hidden_nolink2): Same. * misc/sys/cdefs.h (__attribute_copy__): New macro. * sysdeps/x86_64/multiarch/memchr.c (memchr): Use __attribute_copy__. * sysdeps/x86_64/multiarch/memcmp.c (memcmp): Same. * sysdeps/x86_64/multiarch/mempcpy.c (mempcpy): Same. * sysdeps/x86_64/multiarch/memset.c (memset): Same. * sysdeps/x86_64/multiarch/stpcpy.c (stpcpy): Same. * sysdeps/x86_64/multiarch/strcat.c (strcat): Same. * sysdeps/x86_64/multiarch/strchr.c (strchr): Same. * sysdeps/x86_64/multiarch/strcmp.c (strcmp): Same. * sysdeps/x86_64/multiarch/strcpy.c (strcpy): Same. * sysdeps/x86_64/multiarch/strcspn.c (strcspn): Same. * sysdeps/x86_64/multiarch/strlen.c (strlen): Same. * sysdeps/x86_64/multiarch/strncmp.c (strncmp): Same. * sysdeps/x86_64/multiarch/strncpy.c (strncpy): Same. * sysdeps/x86_64/multiarch/strnlen.c (strnlen): Same. * sysdeps/x86_64/multiarch/strpbrk.c (strpbrk): Same. * sysdeps/x86_64/multiarch/strrchr.c (strrchr): Same. * sysdeps/x86_64/multiarch/strspn.c (strspn): Same.
2018-06-29libc: Extend __libc_freeres framework (Bug 23329).Carlos O'Donell
The __libc_freeres framework does not extend to non-libc.so objects. This causes problems in general for valgrind and mtrace detecting unfreed objects in both libdl.so and libpthread.so. This change is a pre-requisite to properly moving the malloc hooks out of malloc since such a move now requires precise accounting of all allocated data before destructors are run. This commit adds a proper hook in libc.so.6 for both libdl.so and for libpthread.so, this ensures that shm-directory.c which uses freeit () to free memory is called properly. We also remove the nptl_freeres hook and fall back to using weak-ref-and-check idiom for a loaded libpthread.so, thus making this process similar for all DSOs. Lastly we follow best practice and use explicit free calls for both libdl.so and libpthread.so instead of the generic hook process which has undefined order. Tested on x86_64 with no regressions. Signed-off-by: DJ Delorie <dj@redhat.com> Signed-off-by: Carlos O'Donell <carlos@redhat.com>
2018-01-01Update copyright dates with scripts/update-copyrights.Joseph Myers
* All files with FSF copyright notices: Update copyright dates using scripts/update-copyrights. * locale/programs/charmap-kw.h: Regenerated. * locale/programs/locfile-kw.h: Likewise.
2017-10-04Don't use hidden visibility in libc.a with PIE on i386H.J. Lu
On i386, when multi-arch is enabled, all external functions must be called via PIC PLT in PIE, which requires setting up EBX register, since they may be IFUNC functions. * config.h.in (NO_HIDDEN_EXTERN_FUNC_IN_PIE): New. * include/libc-symbols.h (__hidden_proto_hiddenattr): Add check for PIC and NO_HIDDEN_EXTERN_FUNC_IN_PIE. * sysdeps/i386/configure.ac (NO_HIDDEN_EXTERN_FUNC_IN_PIE): New AC_DEFINE if multi-arch is enabled. * sysdeps/i386/configure: Regenerated.
2017-10-03Introduce NO_RTLD_HIDDEN, make hurd use it instead of NO_HIDDENSamuel Thibault
On the Hurd, the rtld needs to see its own dumb versions of a few functions (defined in sysdeps/mach/hurd/dl-sysdep.c) overridden by libc's versions once loaded. rtld should thus not have hidden attribute for these. To achieve this, the Hurd port used to just define NO_HIDDEN, which disables it completely. For now, this changes that to disabling it for all rtld functions, for simplicity. See Roland's comment on https://sourceware.org/bugzilla/show_bug.cgi?id=15605#c5 The ld.so numbers remain at 8 .rel.plt 000000c8 00000c24 00000c24 00000c24 2**2 CONTENTS, ALLOC, LOAD, READONLY, DATA 9 .plt 000001a0 00000cf0 00000cf0 00000cf0 2**4 CONTENTS, ALLOC, LOAD, READONLY, CODE 10 .plt.got 00000010 00000e90 00000e90 00000e90 2**3 CONTENTS, ALLOC, LOAD, READONLY, CODE 18 .got.plt 00000070 0002d000 0002d000 0002c000 2**2 CONTENTS, ALLOC, LOAD, DATA which is about 3 times as much as on Linux. The libc.so numbers get divided by 3 (the remainings are mostly RPC stub calls) * include/libc-symbols.h [NO_RTLD_HIDDEN] (rtld_hidden_proto, rtld_hidden_tls_proto, rtld_hidden_def, rtld_hidden_weak, rtld_hidden_rtld_hidden_ver, data_def, rtld_hidden_data_weak, rtld_hidden_data_ver): Define to empty. * include/assert.h [IS_IN(rtld) && NO_RTLD_HIDDEN] (__assert_fail, __assert_perror_fail): Likewise. * include/dirent.h [IS_IN(rtld) && NO_RTLD_HIDDEN] (__rewinddir): Likewise. * include/libc-internal.h [IS_IN(rtld) && NO_RTLD_HIDDEN] (__profile_frequency): Likewise. * include/setjmp.h (__sigsetjmp): Likewise. * include/signal.h [IS_IN(rtld) && NO_RTLD_HIDDEN] (__sigaction, __libc_sigaction): Likewise. * include/stdlib.h [NO_RTLD_HIDDEN] (unsetenv, __strtoul_internal): Do not set hidden attribute. * include/string.h [IS_IN(rtld) && NO_RTLD_HIDDEN] (__stpcpy, __strdup, __strerror_t, __strsep_g, memchr, memcmp, memcpy, memmove, memset, rawmemchr, stpcpy, strchr, strcmp, strlen, strnlen, strsep): Likewise. * include/sys/stat.h [IS_IN(rtld) && NO_RTLD_HIDDEN] (__fxstat, __fxstat64, __lxstat, __lxstat64, __xstat, __xstat64, __fxstatat64): Likewise. * include/sys/utsname.h [IS_IN(rtld) && NO_RTLD_HIDDEN] (__uname): Likewise. * include/sysdeps/generic/_itoa.h [IS_IN(rtld) && NO_RTLD_HIDDEN] (_itoa_upper_digits, _itoa_lower_digits): Likewise. * sysdeps/mach/hurd/configure.ac (NO_HIDDEN): Do not set. (NO_RTLD_HIDDEN): Set. * sysdeps/mach/hurd/configure: Refresh. * config.h.in: Refresh.
2017-08-31libc-symbols.h: Remove definition of internal_functionFlorian Weimer
2017-08-22Fix remaining return type of ifunc resolver declarationGabriel F. T. Gomes
Since Martin Sebor's commit commit ee4e992ebe5f9712faedeefe8958b67d61eaa0f2 Author: Martin Sebor <msebor@redhat.com> Date: Tue Aug 22 09:35:23 2017 -0600 Declare ifunc resolver to return a pointer to the same type as the target function to help GCC detect incompatibilities between the two when it's enhanced to do so. builds for powerpc64le fail in the declaration of some ifunc resolvers, because the ifunc is declared with unmatching return types. One of the declarations comes from the __ifunc_resolver macro, which was patched by the aforementioned commit: /* Helper / base macros for indirect function symbols. */ #define __ifunc_resolver(type_name, name, expr, arg, init, classifier) \ classifier inhibit_stack_protector \ __typeof (type_name) *name##_ifunc (arg) \ whereas the other comes from the unpatched __ifunc macro when HAVE_GCC_IFUNC is not defined: # define __ifunc(type_name, name, expr, arg, init) \ extern __typeof (type_name) name; \ void *name##_ifunc (arg) __asm__ (#name); \ This patch changes the return type of the ifunc resolver in the __ifunc macro, so that it matches the return type of the target function, similarly to what the aforementioned commit does. Tested for powerpc64le and s390x with unpatched GCC. * include/libc-symbols.h: [!defined HAVE_GCC_IFUNC] (__ifunc): Change the return type of the ifunc resolver to match the return type of the target function.
2017-08-22Declare ifunc resolver to return a pointer to the same type as the targetMartin Sebor
function to help GCC detect incompatibilities between the two when it's enhanced to do so.
2017-08-22Add hidden visibility to internal function prototypesH.J. Lu
Add hidden visibility to internal function prototypes to allow direct access to internal functions within libc.a without using GOT when the compiler defaults to -fPIE. Size comparison of elf/ldconfig when the compiler defaults to -fPIE: On x86-64: text data bss dec hex Before: 619646 20132 5488 645266 9d892 After : 619502 20132 5488 645122 9d802 On i686: text data bss dec hex Before: 550333 10748 3060 564141 89bad After : 546453 10732 3060 560245 88c75 * include/libc-symbols.h (__hidden_proto_hiddenattr): New for building libc.a. (hidden_proto): Likewise. (hidden_tls_proto): Likewise. (__hidden_proto): Likewise. (Reapplied after the revert in df1deda60050cc8a68156cf6c81ad42363647a29.)
2017-08-21Revert "Add hidden visibility to internal function prototypes".Joseph Myers
The commit commit 568ff4296c72534e49c8d9c83c33f3a0069cccc7 Author: H.J. Lu <hjl.tools@gmail.com> Date: Mon Aug 21 05:50:38 2017 -0700 Add hidden visibility to internal function prototypes breaks the build of the testsuite for many platforms: https://sourceware.org/ml/libc-testresults/2017-q3/msg00300.html The errors are of the following form, building math/atest-exp: [...] /scratch/jmyers/glibc-bot/build/glibcs/aarch64-linux-gnu/glibc/stdlib/rshift.o: In function `__mpn_rshift': /scratch/jmyers/glibc-bot/build/glibcs/aarch64-linux-gnu/glibc-src/stdlib/rshift.c:45: undefined reference to `__assert_fail' /scratch/jmyers/glibc-bot/install/compilers/aarch64-linux-gnu/lib/gcc/aarch64-glibc-linux-gnu/7.2.1/../../../../aarch64-glibc-linux-gnu/bin/ld: /scratch/jmyers/glibc-bot/build/glibcs/aarch64-linux-gnu/glibc/math/atest-exp: hidden symbol `__assert_fail' isn't defined /scratch/jmyers/glibc-bot/install/compilers/aarch64-linux-gnu/lib/gcc/aarch64-glibc-linux-gnu/7.2.1/../../../../aarch64-glibc-linux-gnu/bin/ld: final link failed: Bad value This test is using various objects from the build of libc. Some of those objects contain references to __assert_fail. Because those references are hidden, they cannot refer to __assert_fail from libc.so. Given the tests using internal objects those symbols in libc.a can't safely be made hidden, so this patch reverts the problem commit until any alternative approach that doesn't break the build can be found.
2017-08-21Add hidden visibility to internal function prototypesH.J. Lu
Add hidden visibility to internal function prototypes to allow direct access to internal functions within libc.a without using GOT when the compiler defaults to -fPIE. Size comparison of elf/ldconfig when the compiler defaults to -fPIE: On x86-64: text data bss dec hex Before: 619646 20132 5488 645266 9d892 After : 619502 20132 5488 645122 9d802 On i686: text data bss dec hex Before: 550333 10748 3060 564141 89bad After : 546453 10732 3060 560245 88c75 * include/libc-symbols.h (__hidden_proto_hiddenattr): New for building libc.a. (hidden_proto): Likewise. (hidden_tls_proto): Likewise. (__hidden_proto): Likewise.
2017-08-21Enable hidden visibility in libc.a compiled with PIEH.J. Lu
When building libc.a with PIE, enable hidden visibility to allow direct access to definitions within libc.a without using GOT. Size comparison of elf/ldconfig when the compiler defaults to -fPIE: On x86-64: text data bss dec hex Before: 619206 20132 5488 644826 9d6da After : 619062 20132 5488 644682 9d64a On i686: text data bss dec hex Before: 556305 10816 3056 570177 8b341 After : 553688 10756 3056 567500 8a8cc * include/libc-symbols.h (attribute_hidden): Enable hidden visibility in libc.a compiled with PIE.
2017-08-08i386: Add <startup.h> [BZ #21913]H.J. Lu
On Linux/i386, there are 3 ways to make a system call: 1. call *%gs:SYSINFO_OFFSET. This requires TLS initialization. 2. call *_dl_sysinfo. This requires relocation of _dl_sysinfo. 3. int $0x80. This is slower than #2 and #3, but works everywhere. When an object file is compiled with PIC, #1 is prefered since it is faster than #3 and doesn't require relocation of _dl_sysinfo. For dynamic executables, ld.so initializes TLS. However, for static executables, before TLS is initialized by __libc_setup_tls, #3 should be used for system calls. This patch adds <startup.h> which defines _startup_fatal and defaults it to __libc_fatal. It replaces __libc_fatal with _startup_fatal in static executables where it is called before __libc_setup_tls is called. This header file is included in all files containing functions which are called before __libc_setup_tls is called. On Linux/i386, when PIE is enabled by default, _startup_fatal is turned into ABORT_INSTRUCTION and I386_USE_SYSENTER is defined to 0 so that "int $0x80" is used for system calls before __libc_setup_tls is called. Tested on i686 and x86-64. Without this patch, all statically-linked tests will fail on i686 when the compiler defaults to -fPIE. [BZ #21913] * csu/libc-tls.c: Include <startup.h> first. (__libc_setup_tls): Call _startup_fatal instead of __libc_fatal. * elf/dl-tunables.c: Include <startup.h> first. * include/libc-symbols.h (BUILD_PIE_DEFAULT): New. * sysdeps/generic/startup.h: New file. * sysdeps/unix/sysv/linux/i386/startup.h: Likewise. * sysdeps/unix/sysv/linux/i386/brk.c [BUILD_PIE_DEFAULT != 0] (I386_USE_SYSENTER): New. Defined to 0.
2017-05-11Suppress internal declarations for most of the testsuite.Zack Weinberg
This patch adds a new build module called 'testsuite'. IS_IN (testsuite) implies _ISOMAC, as do IS_IN_build and __cplusplus (which means several ad-hoc tests for __cplusplus can go away). libc-symbols.h now suppresses almost all of *itself* when _ISOMAC is defined; in particular, _ISOMAC mode does not get config.h automatically anymore. There are still quite a few tests that need to see internal gunk of one variety or another. For them, we now have 'tests-internal' and 'test-internal-extras'; files in this category will still be compiled with MODULE_NAME=nonlib, and everything proceeds as it always has. The bulk of this patch is moving tests from 'tests' to 'tests-internal'. There is also 'tests-static-internal', which has the same effect on files in 'tests-static', and 'modules-names-tests', which has the *inverse* effect on files in 'modules-names' (it's inverted because most of the things in modules-names are *not* tests). For both of these, the file must appear in *both* the new variable and the old one. There is also now a special case for when libc-symbols.h is included without MODULE_NAME being defined at all. (This happens during the creation of libc-modules.h, and also when preprocessing Versions files.) When this happens, IS_IN is set to be always false and _ISOMAC is *not* defined, which was the status quo, but now it's explicit. The remaining changes to C source files in this patch seemed likely to cause problems in the absence of the main change. They should be relatively self-explanatory. In a few cases I duplicated a definition from an internal header rather than move the test to tests-internal; this was a judgement call each time and I'm happy to change those however reviewers feel is more appropriate. * Makerules: New subdir configuration variables 'tests-internal' and 'test-internal-extras'. Test files in these categories will still be compiled with MODULE_NAME=nonlib. Test files in the existing categories (tests, xtests, test-srcs, test-extras) are now compiled with MODULE_NAME=testsuite. New subdir configuration variable 'modules-names-tests'. Files which are in both 'modules-names' and 'modules-names-tests' will be compiled with MODULE_NAME=testsuite instead of MODULE_NAME=extramodules. (gen-as-const-headers): Move to tests-internal. (do-tests-clean, common-mostlyclean): Support tests-internal. * Makeconfig (built-modules): Add testsuite. * Makefile: Change libof-check-installed-headers-c and libof-check-installed-headers-cxx to 'testsuite'. * Rules: Likewise. Support tests-internal. * benchtests/strcoll-inputs/filelist#en_US.UTF-8: Remove extra-modules.mk. * config.h.in: Don't check for __OPTIMIZE__ or __FAST_MATH__ here. * include/libc-symbols.h: Move definitions of _GNU_SOURCE, PASTE_NAME, PASTE_NAME1, IN_MODULE, IS_IN, and IS_IN_LIB to the very top of the file and rationalize their order. If MODULE_NAME is not defined at all, define IS_IN to always be false, and don't define _ISOMAC. If any of IS_IN (testsuite), IS_IN_build, or __cplusplus are true, define _ISOMAC and suppress everything else in this file, starting with the inclusion of config.h. Do check for inappropriate definitions of __OPTIMIZE__ and __FAST_MATH__ here, but only if _ISOMAC is not defined. Correct some out-of-date commentary. * include/math.h: If _ISOMAC is defined, undefine NO_LONG_DOUBLE and _Mlong_double_ before including math.h. * include/string.h: If _ISOMAC is defined, don't expose _STRING_ARCH_unaligned. Move a comment to a more appropriate location. * include/errno.h, include/stdio.h, include/stdlib.h, include/string.h * include/time.h, include/unistd.h, include/wchar.h: No need to check __cplusplus nor use __BEGIN_DECLS/__END_DECLS. * misc/sys/cdefs.h (__NTHNL): New macro. * sysdeps/m68k/m680x0/fpu/bits/mathinline.h (__m81_defun): Use __NTHNL to avoid errors with GCC 6. * elf/tst-env-setuid-tunables.c: Include config.h with _LIBC defined, for HAVE_TUNABLES. * inet/tst-checks-posix.c: No need to define _ISOMAC. * intl/tst-gettext2.c: Provide own definition of N_. * math/test-signgam-finite-c99.c: No need to define _ISOMAC. * math/test-signgam-main.c: No need to define _ISOMAC. * stdlib/tst-strtod.c: Convert to test-driver. Split locale_test to... * stdlib/tst-strtod1i.c: ...this new file. * stdlib/tst-strtod5.c: Convert to test-driver and add copyright notice. Split tests of __strtod_internal to... * stdlib/tst-strtod5i.c: ...this new file. * string/test-string.h: Include stdint.h. Duplicate definition of inhibit_loop_to_libcall here (from libc-symbols.h). * string/test-strstr.c: Provide dummy definition of libc_hidden_builtin_def when including strstr.c. * sysdeps/ia64/fpu/libm-symbols.h: Suppress entire file in _ISOMAC mode; no need to test __STRICT_ANSI__ nor __cplusplus as well. * sysdeps/x86_64/fpu/math-tests-arch.h: Include cpu-features.h. Don't include init-arch.h. * sysdeps/x86_64/multiarch/test-multiarch.h: Include cpu-features.h. Don't include init-arch.h. * elf/Makefile: Move tst-ptrguard1-static, tst-stackguard1-static, tst-tls1-static, tst-tls2-static, tst-tls3-static, loadtest, unload, unload2, circleload1, neededtest, neededtest2, neededtest3, neededtest4, tst-tls1, tst-tls2, tst-tls3, tst-tls6, tst-tls7, tst-tls8, tst-dlmopen2, tst-ptrguard1, tst-stackguard1, tst-_dl_addr_inside_object, and all of the ifunc tests to tests-internal. Don't add $(modules-names) to test-extras. * inet/Makefile: Move tst-inet6_scopeid_pton to tests-internal. Add tst-deadline to tests-static-internal. * malloc/Makefile: Move tst-mallocstate and tst-scratch_buffer to tests-internal. * misc/Makefile: Move tst-atomic and tst-atomic-long to tests-internal. * nptl/Makefile: Move tst-typesizes, tst-rwlock19, tst-sem11, tst-sem12, tst-sem13, tst-barrier5, tst-signal7, tst-tls3, tst-tls3-malloc, tst-tls5, tst-stackguard1, tst-sem11-static, tst-sem12-static, and tst-stackguard1-static to tests-internal. Link tests-internal with libpthread also. Don't add $(modules-names) to test-extras. * nss/Makefile: Move tst-field to tests-internal. * posix/Makefile: Move bug-regex5, bug-regex20, bug-regex33, tst-rfc3484, tst-rfc3484-2, and tst-rfc3484-3 to tests-internal. * stdlib/Makefile: Move tst-strtod1i, tst-strtod3, tst-strtod4, tst-strtod5i, tst-tls-atexit, and tst-tls-atexit-nodelete to tests-internal. * sunrpc/Makefile: Move tst-svc_register to tests-internal. * sysdeps/powerpc/Makefile: Move test-get_hwcap and test-get_hwcap-static to tests-internal. * sysdeps/unix/sysv/linux/Makefile: Move tst-setgetname to tests-internal. * sysdeps/x86_64/fpu/Makefile: Add all libmvec test modules to modules-names-tests.
2017-04-07getopt: merge _GL_UNUSED annotations from gnulibZack Weinberg
gnulib now has annotations on at least some functions to cater to compilation with -Wunused-parameter. In order to follow suit cleanly, I've added to libc-symbols.h some of the _GL_* macros that gnulib-common.m4 puts into config.h. (I don't think they belong in sys/cdefs.h, at least not without further thought.) At this point all gnulib-side changes to getopt.c have been merged. * include/libc-symbols.h: For gnulib compatibility, define _GL_UNUSED, _GL_UNUSED_LABEL, _GL_ATTRIBUTE_PURE, and _GL_ATTRIBUTE_CONST. * posix/getopt.c (_getopt_initialize): Mark argc and argv parameters with _GL_UNUSED.
2017-03-21Deprecate libnsl by default (only shared library will beThorsten Kukuk
build for backward compatibility, no linking possible) and disable building of libnss_compat, libnss_nis and libnss_nisplus, except --enable-obsolete-nsl option is given to configure. * config.h.in: Add LINK_OBSOLETE_NSL. * config.make.in: Add build-obsolete-nsl. * configure.ac: Add obsolete-nsl option. * include/libc-symbols.h: Define libnsl_hidden_nolink_def. * include/rpcsvc/yp.h: Add missing functions as libnsl_hidden_proto. * include/rpcsvc/nislib.h: Likewise. * include/rpcsvc/ypclnt.h: Likewise. * manual/install.texi: Document --enable-obsolete-nsl. * nis/Makefile: Build only libnsl by default (add build-obsolete-nsl). * nis/nis_add.c: Replace libnsl_hidden_def with libnsl_hidden_nolink_def. * nis/nis_addmember.c: Likewise. * nis/nis_call.c: Likewise. * nis/nis_clone_obj.c: Likewise. * nis/nis_defaults.c: Likeise. * nis/nis_domain_of_r.c: Likewise. * nis/nis_error.c: Likewise. * nis/nis_file.c: Likewise. * nis/nis_free.c: Likewise. * nis_local_names.c: Likewise. * nis/nis_lookup.c: Likewise. * nis/nis_modify.c: Likewise. * nis/nis_print.c: Likewise. * nis/nis_remove.c: Likewise. * nis/nis_table.c: Likewise. * nis/nis_util.c: Likewise. * nis/nis_xdr.c: Likewise. * nis/yp_xdr.c: Likewise. * nis/ypclnt.c: Likewise. * nis/ypupdate_xdr.c: Likewise. * nis/nis_checkpoint.c: Add libnsl_hidden_nolink_def to all functions. * nis/nis_clone_dir.c: Likewise. * nis/nis_clone_res.c: Likewise. * nis/nis_creategroup.c: Likewise. * nis/nis_destroygroup.c: Likewise. * nis/nis_domain_of.c: Likewise. * nis/nis_getservlist.c: Likewise. * nis/nis_ismember.c: Likewise. * nis/nis_mkdir.c: Likewise. * nis/nis_ping.c: Likewise. * nis/nis_print_group_entry.c: Likewise. * nis/nis_removemember.c: Likewise. * nis/nis_rmdir.c: Likewise. * nis/nis_server.c: Likewise. * nis/nis_subr.c: Likewise. * nis/nis_verifygroup.c: Likewise. Signed-off-by: Thorsten Kukuk <kukuk@suse.com>
2017-01-01Update copyright dates with scripts/update-copyrights.Joseph Myers
2016-12-26Do not stack-protect ifunc resolvers [BZ #7065]Nick Alcock
When dynamically linking, ifunc resolvers are called before TLS is initialized, so they cannot be safely stack-protected. We avoid disabling stack-protection on large numbers of files by using __attribute__ ((__optimize__ ("-fno-stack-protector"))) to turn it off just for the resolvers themselves. (We provide the attribute even when statically linking, because we will later use it elsewhere too.)
2016-12-08Make _REENTRANT and _THREAD_SAFE aliases for _POSIX_C_SOURCE=199506L.Zack Weinberg
For many years, the only effect of these macros has been to make unistd.h declare getlogin_r. _POSIX_C_SOURCE >= 199506L also causes this function to be declared. However, people who don't carefully read all the headers might be confused into thinking they need to define _REENTRANT for any threaded code (as was indeed the case a long time ago). Therefore, remove __USE_REENTRANT, and make _REENTRANT and _THREAD_SAFE into synonyms for _POSIX_C_SOURCE=199506L. This will only affect programs that don't select a higher conformance level some other way. For instance, -std=c89 -D_REENTRANT will see a change in visible declarations, but -std=c99 -D_POSIX_C_SOURCE=200809L -D_REENTRANT won't, and -D_REENTRANT all by itself also won't, because _DEFAULT_SOURCE implies _POSIX_C_SOURCE > 199506. * include/features.h: Remove __USE_REENTRANT. Treat _REENTRANT and _THREAD_SAFE the same as _POSIX_C_SOURCE=199506L, if a higher POSIX conformance level has not been selected by other macros. * NEWS, manual/creature.texi: Document this change. * posix/unistd.h, posix/bits/unistd.h: Don't check __USE_REENTRANT. * include/libc-symbols.h: Don't define _REENTRANT. * scripts/check-installed-headers.sh: Don't undefine _REENTRANT.
2016-10-07i386, x86: Use libc_ifunc macro for time, gettimeofday.Stefan Liebler
This patch uses the libc_ifunc_hidden macro to create already existing ifunc functions time and gettimeofday on intel. This way, the libc_hidden_def macro can be used instead of the libc_ifunc_hidden_def one which was only used here. Thus the macro is removed from libc-symbols.h. On i386, the __GI_* symbols do not target the ifunc symbol and thus the redirection construct has to be applied here. ChangeLog: * sysdeps/unix/sysv/linux/x86/gettimeofday.c (__gettimeofday): Use libc_ifunc_hidden macro. Use libc_hidden_def instead of libc_ifunc_hidden_def. * sysdeps/unix/sysv/linux/x86/time.c (time): Likewise. * sysdeps/unix/sysv/linux/i386/gettimeofday.c (__gettimeofday): Redirect ifunced function in header for using it as type of ifunc'ed function. Redefine libc_hidden_def to use fallback non ifunc'ed function for __GI_* symbol. * sysdeps/unix/sysv/linux/i386/time.c (time): Likewise. * include/libc-symbols.h (libc_ifunc_hidden_def, libc_ifunc_hidden_def1): Delete macro.
2016-10-07Use gcc attribute ifunc in libc_ifunc macro instead of inline assembly due ↵Stefan Liebler
to false debuginfo. The current s390 ifunc resolver for vector optimized functions and the common libc_ifunc macro in include/libc-symbols.h uses something like that to generate ifunc'ed functions: extern void *__resolve___strlen(unsigned long int dl_hwcap) asm (strlen); asm (".type strlen, %gnu_indirect_function"); This leads to false debug information: objdump --dwarf=info libc.so: ... <1><1e6424>: Abbrev Number: 43 (DW_TAG_subprogram) <1e6425> DW_AT_external : 1 <1e6425> DW_AT_name : (indirect string, offset: 0x1146e): __resolve___strlen <1e6429> DW_AT_decl_file : 1 <1e642a> DW_AT_decl_line : 23 <1e642b> DW_AT_linkage_name: (indirect string, offset: 0x1147a): strlen <1e642f> DW_AT_prototyped : 1 <1e642f> DW_AT_type : <0x1e4ccd> <1e6433> DW_AT_low_pc : 0x998e0 <1e643b> DW_AT_high_pc : 0x16 <1e6443> DW_AT_frame_base : 1 byte block: 9c (DW_OP_call_frame_cfa) <1e6445> DW_AT_GNU_all_call_sites: 1 <1e6445> DW_AT_sibling : <0x1e6459> <2><1e6449>: Abbrev Number: 44 (DW_TAG_formal_parameter) <1e644a> DW_AT_name : (indirect string, offset: 0x1845): dl_hwcap <1e644e> DW_AT_decl_file : 1 <1e644f> DW_AT_decl_line : 23 <1e6450> DW_AT_type : <0x1e4c8d> <1e6454> DW_AT_location : 0x122115 (location list) ... The debuginfo for the ifunc-resolver function contains the DW_AT_linkage_name field, which names the real function name "strlen". If you perform an inferior function call to strlen in lldb, then it fails due to something like that: "error: no matching function for call to 'strlen' candidate function not viable: no known conversion from 'const char [6]' to 'unsigned long' for 1st argument" The unsigned long is the dl_hwcap argument of the resolver function. The strlen function itself has no debufinfo. The s390 ifunc resolver for memset & co uses something like that: asm (".globl FUNC" ".type FUNC, @gnu_indirect_function" ".set FUNC, __resolve_FUNC"); This way the debuginfo for the ifunc-resolver function does not conain the DW_AT_linkage_name field and the real function has no debuginfo, too. Using this strategy for the vector optimized functions leads to some troubles for functions like strnlen. Here we have __strnlen and a weak alias strnlen. The __strnlen function is the ifunc function, which is realized with the asm- statement above. The weak_alias-macro can't be used here due to undefined symbol: gcc ../sysdeps/s390/multiarch/strnlen.c -c ... In file included from <command-line>:0:0: ../sysdeps/s390/multiarch/strnlen.c:28:24: error: ‘strnlen’ aliased to undefined symbol ‘__strnlen’ weak_alias (__strnlen, strnlen) ^ ./../include/libc-symbols.h:111:26: note: in definition of macro ‘_weak_alias’ extern __typeof (name) aliasname __attribute__ ((weak, alias (#name))); ^ ../sysdeps/s390/multiarch/strnlen.c:28:1: note: in expansion of macro ‘weak_alias’ weak_alias (__strnlen, strnlen) ^ make[2]: *** [build/string/strnlen.o] Error 1 As the __strnlen function is defined with asm-statements the function name __strnlen isn't known by gcc. But the weak alias can also be done with an asm statement to resolve this issue: __asm__ (".weak strnlen\n\t" ".set strnlen,__strnlen\n"); In order to use the weak_alias macro, gcc needs to know the ifunc function. The minimum gcc to build glibc is currently 4.7, which supports attribute((ifunc)). See https://gcc.gnu.org/onlinedocs/gcc-4.7.0/gcc/Function-Attributes.html. It is only supported if gcc is configured with --enable-gnu-indirect-function or gcc supports it by default for at least intel and s390x architecture. This patch uses the old behaviour if gcc support is not available. Usage of attribute ifunc is something like that: __typeof (FUNC) FUNC __attribute__ ((ifunc ("__resolve_FUNC"))); Then gcc produces the same .globl, .type, .set assembler instructions like above. And the debuginfo does not contain the DW_AT_linkage_name field and there is no debuginfo for the real function, too. But in order to get it work, there is also some extra work to do. Currently, the glibc internal symbol on s390x e.g. __GI___strnlen is not the ifunc symbol, but the fallback __strnlen_c symbol. Thus I have to omit the libc_hidden_def macro in strnlen.c (here is the ifunc function __strnlen) because it is already handled in strnlen-c.c (here is __strnlen_c). Due to libc_hidden_proto (__strnlen) in string.h, compiling fails: gcc ../sysdeps/s390/multiarch/strnlen.c -c ... In file included from <command-line>:0:0: ../sysdeps/s390/multiarch/strnlen.c:53:24: error: ‘strnlen’ aliased to undefined symbol ‘__strnlen’ weak_alias (__strnlen, strnlen) ^ ./../include/libc-symbols.h:111:26: note: in definition of macro ‘_weak_alias’ extern __typeof (name) aliasname __attribute__ ((weak, alias (#name))); ^ ../sysdeps/s390/multiarch/strnlen.c:53:1: note: in expansion of macro ‘weak_alias’ weak_alias (__strnlen, strnlen) ^ make[2]: *** [build/string/strnlen.os] Error 1 I have to redirect the prototypes for __strnlen in string.h and create a copy of the prototype for using as ifunc function: __typeof (__redirect___strnlen) __strnlen __attribute__ ((ifunc ("__resolve_strnlen"))); weak_alias (__strnlen, strnlen) This way there is no trouble with the internal __GI_* symbols. Glibc builds fine with this construct and the debuginfo is "correct". For functions without a __GI_* symbol like memccpy this redirection is not needed. This patch adjusts the common libc_ifunc and libm_ifunc macro to use gcc attribute ifunc. Due to this change, the macro users where the __GI_* symbol does not target the ifunc symbol have to be prepared with the redirection construct. Furthermore a configure check to test gcc support is added. If it is not supported, the old behaviour is used. This patch also prepares the libc_ifunc macro to be useable in s390-ifunc-macro. The s390 ifunc-resolver-functions do have an hwcaps parameter and not all resolvers need the same initialization code. The next patch in this series changes the s390 ifunc macros to use this common one. ChangeLog: * include/libc-symbols.h (__ifunc_resolver): New macro is used by __ifunc* macros. (__ifunc): New macro uses gcc attribute ifunc or inline assembly depending on HAVE_GCC_IFUNC. (libc_ifunc, libm_ifunc): Use __ifunc as base macro. (libc_ifunc_redirected, libc_ifunc_hidden, libm_ifunc_init): New macro. * sysdeps/powerpc/powerpc32/power4/fpu/multiarch/s_finite.c: Redirect ifunced function in header for using as type for ifunc function. * sysdeps/powerpc/powerpc32/power4/fpu/multiarch/s_finitef.c: Likewise. * sysdeps/powerpc/powerpc32/power4/fpu/multiarch/s_isinf.c: Likewise. * sysdeps/powerpc/powerpc32/power4/fpu/multiarch/s_isinff.c: Likewise. * sysdeps/powerpc/powerpc32/power4/fpu/multiarch/s_isnan.c: Likewise. * sysdeps/powerpc/powerpc32/power4/multiarch/memcmp.c: Likewise. * sysdeps/powerpc/powerpc32/power4/multiarch/memcpy.c: Likewise. * sysdeps/powerpc/powerpc32/power4/multiarch/memmove.c: Likewise. * sysdeps/powerpc/powerpc32/power4/multiarch/mempcpy.c: Likewise. * sysdeps/powerpc/powerpc32/power4/multiarch/memset.c: Likewise. * sysdeps/powerpc/powerpc32/power4/multiarch/rawmemchr.c: Likewise. * sysdeps/powerpc/powerpc32/power4/multiarch/strchr.c: Likewise. * sysdeps/powerpc/powerpc32/power4/multiarch/strlen.c: Likewise. * sysdeps/powerpc/powerpc32/power4/multiarch/strncmp.c: Likewise. * sysdeps/powerpc/powerpc32/power4/multiarch/strnlen.c: Likewise. * sysdeps/powerpc/powerpc64/fpu/multiarch/s_finite.c: Likewise. * sysdeps/powerpc/powerpc64/fpu/multiarch/s_finitef.c: Likewise. * sysdeps/powerpc/powerpc64/fpu/multiarch/s_isinf.c: Likewise. * sysdeps/powerpc/powerpc64/fpu/multiarch/s_isinff.c: Likewise. * sysdeps/powerpc/powerpc64/fpu/multiarch/s_isnan.c: Likewise. * sysdeps/powerpc/powerpc64/multiarch/memcmp.c: Likewise. * sysdeps/powerpc/powerpc64/multiarch/mempcpy.c: Likewise. * sysdeps/powerpc/powerpc64/multiarch/rawmemchr.c: Likewise. * sysdeps/powerpc/powerpc64/multiarch/stpncpy.c: Likewise. * sysdeps/powerpc/powerpc64/multiarch/strcat.c: Likewise. * sysdeps/powerpc/powerpc64/multiarch/strchr.c: Likewise. * sysdeps/powerpc/powerpc64/multiarch/strcmp.c: Likewise. * sysdeps/powerpc/powerpc64/multiarch/strcpy.c: Likewise. * sysdeps/powerpc/powerpc64/multiarch/strncmp.c: Likewise. * sysdeps/powerpc/powerpc64/multiarch/strncpy.c: Likewise. * sysdeps/powerpc/powerpc64/multiarch/strnlen.c: Likewise. * sysdeps/powerpc/powerpc64/multiarch/strrchr.c: Likewise. * sysdeps/powerpc/powerpc64/multiarch/strstr.c: Likewise. * sysdeps/powerpc/powerpc64/multiarch/wcschr.c: Likewise. * sysdeps/powerpc/powerpc32/power4/fpu/multiarch/s_isnanf.c: Add libc_hidden_def() and use libc_ifunc_hidden() macro instead of libc_ifunc() macro. * sysdeps/powerpc/powerpc64/fpu/multiarch/s_isnanf.c: Likewise. * sysdeps/powerpc/powerpc64/multiarch/stpcpy.c: Likewise.
2016-08-26malloc: Simplify static malloc interposition [BZ #20432]Florian Weimer
Existing interposed mallocs do not define the glibc-internal fork callbacks (and they should not), so statically interposed mallocs lead to link failures because the strong reference from fork pulls in glibc's malloc, resulting in multiple definitions of malloc-related symbols.
2016-08-02Add support for referencing specific symbol versionsFlorian Weimer
This is needed for writing tests of compat symbols.
2016-01-04Update copyright dates with scripts/update-copyrights.Joseph Myers
2015-10-19Remove .weak, .weakext configure tests.Joseph Myers
There are configure tests for assembler .weak support, and, as a fallback, for .weakext support. .weakext appears to be an ECOFF thing (although a few ELF targets support it as well). .weak has been supported by the GNU assembler for ELF targets since version 2.2, so given the requirement for ELF the configure tests are obsolete; this patch removes them. Tested for x86_64 (testsuite, and that installed shared libraries are unchanged by the patch). * configure.ac (libc_cv_asm_weak_directive): Remove configure test. (libc_cv_asm_weakext_directive): Likewise. * configure: Regenerated. * config.h.in (HAVE_ASM_WEAK_DIRECTIVE): Remove #undef. (HAVE_ASM_WEAKEXT_DIRECTIVE): Likewise. * include/libc-symbols.h [!HAVE_ASM_WEAK_DIRECTIVE && !HAVE_ASM_WEAKEXT_DIRECTIVE]: Remove #error. [HAVE_ASM_WEAKEXT_DIRECTIVE]: Remove conditional code. [!HAVE_ASM_WEAKEXT_DIRECTIVE]: Make code unconditional.
2015-10-15Remove .previous, .popsection configure tests.Joseph Myers
There is a configure test for the assembler .previous directive, and, as a fallback, for .popsection. glibc now only supports ELF. For ELF, the GNU assembler has supported .previous since version 2.2 (support added by Mon Jul 19 15:21:20 1993 Ken Raeburn (raeburn@rtl.cygnus.com) * config/obj-elf.c (obj_elf_previous): New function. (previous_section, previous_subsection): New vars. (obj_elf_section): Save current place in case DWARF code wants us to pop back to it. Handle unquoted section name as well as quoted section name. Don't crash on invalid strings. (obj_pseudo_table): Handle new pseudos "previous", "2byte", and "4byte". ). Thus this configure test is obsolete, and this patch removes it (and with it the fallback .popsection test). Tested for x86_64 and x86 (testsuite, and that installed shared libraries are unchanged by the patch). * configure.ac (libc_cv_asm_previous_directive): Remove configure test. (libc_cv_asm_popsection_directive): Likewise. * configure: Regenerated. * config.h.in (HAVE_ASM_PREVIOUS_DIRECTIVE): Remove #undef. (HAVE_ASM_POPSECTION_DIRECTIVE): Likewise. * include/libc-symbols.h [HAVE_ASM_PREVIOUS_DIRECTIVE] (__make_section_unallocated): Make definition unconditional. [HAVE_ASM_POPSECTION_DIRECTIVE] (__make_section_unallocated): Remove conditional definition. [!HAVE_ASM_PREVIOUS_DIRECTIVE && !HAVE_ASM_POPSECTION_DIRECTIVE] (__make_section_unallocated): Likewise.
2015-05-25Localplt testing for vector math library and libmvec_hidden_* macro series.Andrew Senkevich
* elf/Makefile (localplt-built-dso): libmvec added to localplt test. * include/libc-symbols.h: libmvec_hidden_* macro series added.