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2017-08-31elf: Remove internal_function attributeFlorian Weimer
2017-08-31gmon: Remove internal_function attributeFlorian Weimer
2017-08-31dlfcn: Remove internal_function attributeFlorian Weimer
2017-08-31resolv: Remove internal_function attributeFlorian Weimer
2017-08-31dirent: Remove internal_function attributeFlorian Weimer
2017-08-31Linux getcwd: Remove internal_function attributeFlorian Weimer
2017-08-31time: Remove the internal_function attributeFlorian Weimer
2017-08-31iconv, intl, locale, wcsmbs: Remove internal_functionFlorian Weimer
Also adjust parts of the time subdirectory.
2017-08-31aio: Remove internal_function function attributeFlorian Weimer
2017-08-31misc: Remove internal_function function attributeFlorian Weimer
2017-08-31NSS: Remove internal_function function attributeFlorian Weimer
2017-08-31malloc: Remove the internal_function attributeFlorian Weimer
2017-08-31sunrpc: Remove internal_function attributeFlorian Weimer
2017-08-31malloc: Resolve compilation failure in NDEBUG modeFlorian Weimer
In _int_free, the locked variable is not used if NDEBUG is defined.
2017-08-31Place $(elf-objpfx)sofini.os last [BZ #22051]H.J. Lu
Since sofini.os terminates .eh_frame section, it should be placed last. [BZ #22051] * Makerules (build-module-helper-objlist): Filter out $(elf-objpfx)sofini.os. (build-shlib-objlist): Append $(elf-objpfx)sofini.os if it is needed.
2017-08-31libio: Assume _LIBC, weak_alias, errno, (__set_)errno &c are definedFlorian Weimer
Do not define _POSIX_SOURCE.
2017-08-31malloc: Change top_check return type to voidFlorian Weimer
After commit ec2c1fcefb200c6cb7e09553f3c6af8815013d83, (malloc: Abort on heap corruption, without a backtrace), the function always returns 0.
2017-08-31Fix decimal point and thousands separator in es_CU locale to agree with CLDR.Mike FABIAN
[BZ #15332] * locales/es_CU (LC_MONETARY): use “,” for mon_decimal_point and “.” for mon_thousands_sep (to agree with CLDR) * locales/es_CU (LC_NUMERIC): Likewise.
2017-08-31Remove redundant data in li_BE which is identical to the data in li_NLAkhilesh Kumar
[BZ #22044] * locales/li_BE (LC_TIME): copy "li_NL".
2017-08-30Fix mcontext_t sigcontext namespace (bug 21457).Joseph Myers
This patch completes the ucontext.h namespace fixes by fixing issues related to the use of struct sigcontext as mcontext_t, and inclusion of <bits/sigcontext.h> even when struct sigcontext is not so used. Inclusion of <bits/sigcontext.h> by <sys/ucontext.h> is removed; the way to get the sigcontext structure is by including <signal.h> (in a context where __USE_MISC is defined); the sysdeps/generic version of sys/ucontext.h keeps the inclusion by necessity, with a comment about how this is not namespace-clean, but the only configuration that used it, MicroBlaze, gets its own version of the header in this patch. Where mcontext_t was typedefed to struct sigcontext, the contents of struct sigcontext are inserted (with appropriate namespace handling to prefix fields with __ when __USE_MISC is not defined); review should check that this has been done correctly in each case, whether the definition of struct sigcontext comes from glibc headers or from the Linux kernel. This changes C++ name mangling on affected architectures (which do not include x86_64/x86). Tested for x86_64, and with build-many-glibcs.py. 2017-08-14 Joseph Myers <joseph@codesourcery.com> [BZ #21457] * sysdeps/arm/sys/ucontext.h: Do not include <bits/sigcontext.h>. * sysdeps/generic/sys/ucontext.h: Add comment about use of struct sigcontext and namespace requirements. * sysdeps/i386/sys/ucontext.h: Do not include <bits/sigcontext.h>. * sysdeps/m68k/sys/ucontext.h: Likewise. * sysdeps/mips/sys/ucontext.h: Likewise. Include <bits/types.h>. * sysdeps/unix/sysv/linux/aarch64/sys/ucontext.h: Do not include <bits/sigcontext.h>. (__ctx): Define earlier. (mcontext_t): Define structure contents rather than using struct sigcontext. * sysdeps/unix/sysv/linux/aarch64/ucontext_i.sym (oEXTENSION): Use __glibc_reserved1 instead of __reserved. * sysdeps/unix/sysv/linux/alpha/sys/ucontext.h: Do not include <bits/sigcontext.h>. (__ctx): Define earlier. (mcontext_t): Define structure contents rather than using struct sigcontext. * sysdeps/unix/sysv/linux/alpha/ucontext-offsets.sym: Use mcontext_t instead of struct sigcontext. * sysdeps/unix/sysv/linux/arm/sys/ucontext.h: Do not include <bits/sigcontext.h>. (__ctx): Define earlier. (mcontext_t): Define structure contents rather than using struct sigcontext. * sysdeps/unix/sysv/linux/hppa/sys/ucontext.h: Do not include <bits/sigcontext.h>. (__ctx): Define earlier. (mcontext_t): Define structure contents rather than using struct sigcontext. * sysdeps/unix/sysv/linux/ia64/makecontext.c (__makecontext): Use mcontext_t instead of struct sigcontext. * sysdeps/unix/sysv/linux/ia64/sigcontext-offsets.sym: Use mcontext_t instead of struct sigcontext. * sysdeps/unix/sysv/linux/ia64/sys/ucontext.h: Do not include <bits/sigcontext.h>. (__ctx): New macro. (struct __ia64_fpreg_mcontext): New type. (mcontext_t): Define structure contents rather than using struct sigcontext. (_SC_GR0_OFFSET): Use mcontext_t instead of struct sigcontext. (uc_sigmask): Define using __ctx. (uc_stack): Likewise. * sysdeps/unix/sysv/linux/ia64/sys/procfs.h: Include <bits/sigcontext.h>. * sysdeps/unix/sysv/linux/ia64/sys/ptrace.h: Likewise. * sysdeps/unix/sysv/linux/m68k/sys/ucontext.h: Do not include <bits/sigcontext.h>. * sysdeps/unix/sysv/linux/microblaze/sys/ucontext.h: New file. * sysdeps/unix/sysv/linux/mips/sys/ucontext.h: Do not include <bits/sigcontext.h>. * sysdeps/unix/sysv/linux/nios2/sys/ucontext.h: Do not include <bits/sigcontext.h>. * sysdeps/unix/sysv/linux/powerpc/sys/ucontext.h: Do not include <bits/sigcontext.h>. * sysdeps/unix/sysv/linux/s390/sys/ucontext.h: Do not include <bits/sigcontext.h>. * sysdeps/unix/sysv/linux/sh/sys/ucontext.h: Do not include <bits/sigcontext.h>. * sysdeps/unix/sysv/linux/sparc/sys/ucontext.h: Do not include <bits/sigcontext.h>. * sysdeps/unix/sysv/linux/tile/sys/ucontext.h: Do not include <bits/sigcontext.h>. (__ctx): Define earlier. (mcontext_t): Define structure contents rather than using struct sigcontext. * sysdeps/unix/sysv/linux/x86/sys/ucontext.h: Do not include <bits/sigcontext.h>. Include <bits/types.h>. * conform/Makefile (test-xfail-XPG42/signal.h/conform): Remove. (test-xfail-XPG42/sys/wait.h/conform): Likewise. (test-xfail-XPG42/ucontext.h/conform): Likewise. (test-xfail-UNIX98/signal.h/conform): Likewise. (test-xfail-UNIX98/sys/wait.h/conform): Likewise. (test-xfail-UNIX98/ucontext.h/conform): Likewise. (test-xfail-XOPEN2K/signal.h/conform): Likewise. (test-xfail-XOPEN2K/sys/wait.h/conform): Likewise. (test-xfail-XOPEN2K/ucontext.h/conform): Likewise. (test-xfail-POSIX2008/signal.h/conform): Likewise. (test-xfail-POSIX2008/sys/wait.h/conform): Likewise. (test-xfail-XOPEN2K8/signal.h/conform): Likewise. (test-xfail-XOPEN2K8/sys/wait.h/conform): Likewise.
2017-08-30dynarray: Set errno on overflow-induced allocation failureFlorian Weimer
This allows the caller to return directly on such an error, with an appropriate errno value.
2017-08-30malloc: Remove corrupt arena flagFlorian Weimer
This is no longer needed because we now abort immediately once heap corruption is detected.
2017-08-30malloc: Remove check_action variable [BZ #21754]Florian Weimer
Clean up calls to malloc_printerr and trim its argument list. This also removes a few bits of work done before calling malloc_printerr (such as unlocking operations). The tunable/environment variable still enables the lightweight additional malloc checking, but mallopt (M_CHECK_ACTION) no longer has any effect.
2017-08-30aarch64: Fix tst-makecontext3 in ILP32 mode.Steve Ellcey
* sysdeps/unix/sysv/linux/aarch64/makecontext.c (__makecontext): Use pointer to uint64_t instead of long int for sp.
2017-08-30malloc: Abort on heap corruption, without a backtrace [BZ #21754]Florian Weimer
The stack trace printing caused deadlocks and has been itself been targeted by code execution exploits.
2017-08-30Do not scale NPTL tests with available number of CPUsFlorian Weimer
On very large multi-processor systems, creating hundreds of threads runs into a test time out. The tests do not seem to benefit from massive over-scheduling.
2017-08-30Use “.” in thousands_sep in the ca_ES localeMike FABIAN
[BZ #16148] * locales/ca_ES (LC_NUMERIC): Use “.” in thousands_sep. And make it more readable by using ASCII.
2017-08-30Add country_name for mni_INMike FABIAN
[BZ #22022] * locales/mni_IN (LC_ADDRESS): Add country_name.
2017-08-30Fix abbreviated weeks and months for Somali to agree with CLDRAkhilesh Kumar
[BZ #22038] * locales/so_DJ (LC_TIME): Fix abday, abmon and make t_fmt in the comment agree with the value of t_fmt. * locales/so_ET (LC_TIME): Fix abday (From Axa to Axd) * locales/so_KE (LC_TIME): Fix abday (From Axa to Axd) * locales/so_SO (LC_TIME): Fix abday (From Axa to Axd)
2017-08-29Update hanzi collation by strokeWei-Lun Chao
[BZ #21951] * locales/cns11643_stroke: Update hanzi collation by stroke (Add license declaration, use strokes by component).
2017-08-29Fix m68k bits/math-inline.h macro namespace (bug 22035).Joseph Myers
As shown by build bot failures <https://sourceware.org/ml/libc-testresults/2017-q3/msg00349.html> the m68k bits/mathinline.h is not namespace-clean: it fails to compile if the user has defined macros f or l before it is included, because of expansions of those arguments to __inline_functions. This patch changes the __inline_functions definitions to take not the suffix but a macro that concatenates it with the function name, to avoid the spurious macro expansions. Tested for m68k with build-many-glibcs.py. [BZ #22035] * sysdeps/m68k/m680x0/fpu/bits/mathinline.h (__inline_functions): Define to take a second argument that is a macro that concatentates a suffix, not the suffix itself. (__CONCAT_d): New macro. (__CONCAT_f): Likewise. (__CONCAT_l): Likewise.
2017-08-292017-08-29 Paul Pluzhnikov <ppluzhnikov@google.com>Paul Pluzhnikov
* stdlib/tst-atexit-common.c (do_test): Test handler inheritance by child.
2017-08-29MIPS/o32: Fix internal_syscall5/6/7Adhemerval Zanella
Fix a commit cc25c8b4c119 ("New pthread rwlock that is more scalable.") regression and prevent uncontrolled stack space usage from happening when a 5-, 6- or 7-argument syscall wrapper is placed in a loop. The cause of the problem is the use of `alloca' in regular MIPS/Linux wrappers to force the use of the frame pointer register in any function using one or more of these wrappers. Using the frame pointer register is required so as not to break frame unwinding as the the stack pointer is lowered within the inline asm used by these wrappers to make room for the stack arguments, which 5-, 6- and 7-argument syscalls use with the o32 ABI. The regular MIPS/Linux wrappers are macros however, expanded inline, and stack allocations made with `alloca' are not discarded until the return of the function they are made in. Consequently if called in a loop, then virtual memory is wasted, and if the loop goes through enough iterations, then ultimately available memory can get exhausted causing the program to crash. Address the issue by replacing the inline code with standalone assembly functions, which rely on the compiler arranging syscall arguments according to the o32 function calling convention, which MIPS/Linux syscalls also use, except for the syscall number passed and the error flag returned. This way there is no need to fiddle with the stack pointer anymore and all that has to be handled in the new standalone functions is the special handling of the syscall number and the error flag. Redirect 5-, 6- or 7-argument MIPS16/Linux syscall wrappers to these new functions as well, so as to avoid an unnecessary double call the existing wrappers would cause with the new arrangement. [BZ #21956] * sysdeps/unix/sysv/linux/mips/mips32/mips16/Makefile [subdir = misc] (sysdep_routines): Remove `mips16-syscall5', `mips16-syscall6' and `mips16-syscall7'. (CFLAGS-mips16-syscall5.c, CFLAGS-mips16-syscall6.c) (CFLAGS-mips16-syscall7.c): Remove. * sysdeps/unix/sysv/linux/mips/mips32/mips16/Versions (libc): Remove `__mips16_syscall5', `__mips16_syscall6' and `__mips16_syscall7'. * sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall0.c (__mips16_syscall0): Rename `__mips16_syscall_return' to `__mips_syscall_return'. * sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall1.c (__mips16_syscall1): Likewise. * sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall2.c (__mips16_syscall2): Likewise. * sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall3.c (__mips16_syscall3): Likewise. * sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall4.c (__mips16_syscall4): Likewise. * sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall5.c: Remove. * sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall6.c: Remove. * sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall7.c: Remove. * sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall.h (__mips16_syscall5): Expand to `__mips_syscall5' rather than `__mips16_syscall5'. Remove prototype. (__mips16_syscall6): Expand to `__mips_syscall6' rather than `__mips16_syscall6'. Remove prototype. (__mips16_syscall7): Expand to `__mips_syscall7' rather than `__mips16_syscall7'. Remove prototype. (__nomips16, __mips16_syscall_return): Move to... * sysdeps/unix/sysv/linux/mips/mips32/sysdep.h (__nomips16, __mips_syscall_return): ... here. [__mips16] (INTERNAL_SYSCALL_NCS): Rename `__mips16_syscall_return' to `__mips_syscall_return'. [__mips16] (INTERNAL_SYSCALL_MIPS16): Pass `number' to `internal_syscall##nr'. [!__mips16] (INTERNAL_SYSCALL): Pass `SYS_ify (name)' to `internal_syscall##nr'. (FORCE_FRAME_POINTER): Remove. (__mips_syscall5): New prototype. (internal_syscall5): Rewrite to call `__mips_syscall5'. (__mips_syscall6): New prototype. (internal_syscall6): Rewrite to call `__mips_syscall6'. (__mips_syscall7): New prototype. (internal_syscall7): Rewrite to call `__mips_syscall7'. * sysdeps/unix/sysv/linux/mips/mips32/mips-syscall5.S: New file. * sysdeps/unix/sysv/linux/mips/mips32/mips-syscall6.S: New file. * sysdeps/unix/sysv/linux/mips/mips32/mips-syscall7.S: New file. * sysdeps/unix/sysv/linux/mips/mips32/Makefile [subdir = misc] (sysdep_routines): Add libc-do-syscall. * sysdeps/unix/sysv/linux/mips/mips32/Versions (libc): Add `__mips_syscall5', `__mips_syscall6' and `__mips_syscall7'.
2017-08-29ia64: Fix thread stack allocation permission set (BZ #21672)Adhemerval Zanella
This patch fixes ia64 failures on thread exit by madvise the required area taking in consideration its disjoing stacks (NEED_SEPARATE_REGISTER_STACK). Also the snippet that setup the madvise call to advertise kernel the area won't be used anymore in near future is reallocated in allocatestack.c (for consistency to put all stack management function in one place). Checked on x86_64-linux-gnu and i686-linux-gnu for sanity (since it is not expected code changes for architecture that do not define NEED_SEPARATE_REGISTER_STACK) and also got a report that it fixes ia64-linux-gnu failures from Sergei Trofimovich <slyfox@gentoo.org>. [BZ #21672] * nptl/allocatestack.c [_STACK_GROWS_DOWN] (setup_stack_prot): Set to use !NEED_SEPARATE_REGISTER_STACK as well. (advise_stack_range): New function. * nptl/pthread_create.c (START_THREAD_DEFN): Move logic to mark stack non required to advise_stack_range at allocatestack.c
2017-08-29[AArch64] Fix procfs.h not to expose stdint.h typesSzabolcs Nagy
Commit 39e7a5a66828a60008543db5f03f46dc7081668b added stdint.h to sys/procfs.h, but it is included into signal.h by default and there is code that does not expect stdint.h to be visible there, so use __uint64_t instead of uint64_t.
2017-08-29iconv_open: Fix heap corruption on gconv_init failure [BZ #22026]Florian Weimer
Also mangle the __end_fct function pointer on the error handling path.
2017-08-29iconv: Mangle __btowc_fct even without __init_fct [BZ #22025]Florian Weimer
2017-08-29Fix bits/math-finite.h _MSUF_ expansion namespace (bug 22028).Joseph Myers
The current bits/math-finite.h approach to defining functions for different types, involving math.h defining _MSUF_ and _MSUFTO_ for the function suffixes involved, is not namespace-clean if one of those suffixes (f, l, f128) is defined as a macro by the user before math.h is included; too many levels of macro expansion occur. Instead, those suffixes should appear directly in the expansion of the macro using ## so they don't get expanded even if defined as macros by the user (that is, math.h should be defining __REDIRFROM_X and __REDIRTO_X directly to use those suffixes rather than suffixes being passed as an argument by macro callers). This patch makes that change. Tested for x86_64. [BZ #22028] * math/math.h [__FINITE_MATH_ONLY__ && __FINITE_MATH_ONLY__ > 0] (_MSUF_): Remove macro. [__FINITE_MATH_ONLY__ && __FINITE_MATH_ONLY__ > 0] (_MSUFTO_): Likewise. [__FINITE_MATH_ONLY__ && __FINITE_MATH_ONLY__ > 0] (__REDIRFROM_X): New macro. [__FINITE_MATH_ONLY__ && __FINITE_MATH_ONLY__ > 0] (__REDIRTO_X): Likewise. * math/bits/math-finite.h (__REDIRFROM_X): Remove macro. (__REDIRTO_X): Likewise. (__MATH_REDIRCALL): Do not pass _MSUF_ or _MSUFTO_ macro arguments. (__MATH_REDIRCALL_2): Likewise. (__MATH_REDIRCALL_INTERNAL): Likewise. (__REDIRFROM (lgamma, , _MSUF_)): Likewise. (__REDIRFROM (gamma, , _MSUF_)): Likweise. (__REDIRFROM (__gamma, _r_finite, _MSUF_)): Likewise. (__REDIRFROM (tgamma, , _MSUF_)): Likewise. * math/test-finite-macros.c: New file. * math/Makefile (tests): Add test-finite-macros. (CFLAGS-test-finite-macros.c): New variable.
2017-08-29gconv: Consistently mangle NULL function pointers [BZ #22025]Patsy Franklin
Not mangling NULL pointers is not safe because with very low probability, a non-NULL function pointer can turn into a NULL pointer after mangling.
2017-08-29Use “,” as mon_decimal_point for ru_RU and os_RU locales (follow CLDR)Mike FABIAN
[BZ #13805] * locales/ru_RU (LC_MONETARY): Use “,” for mon_decimal_point (to agree with CLDR). * locales/ru_RU (LC_NUMERIC): Write mon_decimal_point in ASCII for readability. * locales/os_RU (LC_MONETARY): Copy from ru_RU, makes it agree with CLDR.
2017-08-29Add locale for mfe_MUAkhilesh Kumar
Add locale for “Morisyen” which is also called “Mauritian Creole” and is spoken in Mauritius. [BZ #21971] * localedata/SUPPORTED: Add mfe_MU/UTF-8. * localedata/locales/mfe_MU: New File. [BZ #21971] * locale/iso-639.def: add Morisyen.
2017-08-29Use NFC for the strings in “day”, “yesstr”, and “nostr” in the ↵Mike FABIAN
sgs_LT locale * locales/sgs_LT (LC_TIME): Use NFC for the strings in “day”. * locales/sgs_LT (LC_MESSAGES): Use NFC for “yesstr” and “nostr”.
2017-08-28Provide a C++ version of iszero that does not use __MATH_TG (bug 21930)Gabriel F. T. Gomes
When signaling nans are enabled (with -fsignaling-nans), the C++ version of iszero uses the fpclassify macro, which is defined with __MATH_TG. However, when support for float128 is available, __MATH_TG uses the builtin __builtin_types_compatible_p, which is only available in C mode. This patch refactors the C++ version of iszero so that it uses function overloading to select between the floating-point types, instead of relying on fpclassify and __MATH_TG. Tested for powerpc64le, s390x, x86_64, and with build-many-glibcs.py. [BZ #21930] * math/math.h [defined __cplusplus && defined __SUPPORT_SNAN__] (iszero): New C++ implementation that does not use fpclassify/__MATH_TG/__builtin_types_compatible_p, when signaling nans are enabled, since __builtin_types_compatible_p is a C-only feature. * math/test-math-iszero.cc: When __HAVE_DISTINCT_FLOAT128 is defined, include ieee754_float128.h for access to the union and member ieee854_float128.ieee. [__HAVE_DISTINCT_FLOAT128] (do_test): Call check_float128. [__HAVE_DISTINCT_FLOAT128] (check_float128): New function. * sysdeps/powerpc/powerpc64le/Makefile [subdir == math] (CXXFLAGS-test-math-iszero.cc): Add -mfloat128 to the build options of test-math-zero on powerpc64le.
2017-08-28Fix country_name in zu_ZA to agree with CLDRAkhilesh Kumar
[BZ #21959] * locales/zu_ZA (LC_ADDRESS): Fix country name to agree with CLDR.
2017-08-28x86_64 __redirect_ieee754_expf: Change double to floatH.J. Lu
__redirect_ieee754_expf has type float, not double. * sysdeps/x86_64/fpu/multiarch/e_expf.c (__redirect_ieee754_expf): Change double to float.
2017-08-28Simplify math-svid-compat code.Joseph Myers
Now there are no more assembly wrappers using _LIB_VERSION or __kernel_standard, the math-svid-compat code can be slighly simplified. math-svid-compat.h no longer needs __ASSEMBLER__ conditionals, and the _LIB_VERSION variable no longer needs to be built for static libm, since all references are now in C code that includes math-svid-compat.h and so gets the macro definition of _LIB_VERSION to _POSIX_ outside the compat case. This patch makes those cleanups. Tested for x86_64, and with build-many-glibcs.py. * math/math-svid-compat.h [!__ASSEMBLER__]: Make code unconditional. * sysdeps/ieee754/s_lib_version.c [!defined SHARED]: Remove conditional code; define contents only for [LIBM_SVID_COMPAT].
2017-08-28Remove abi-*-options compiler flagsFlorian Weimer
These options are no longer needed since commit 2dba5ce7b8115d6a2789bf279892263621088e74 (<bits/syscall.h>: Use an arch-independent system call list on Linux).
2017-08-28hurd: Remove duplicate symbol versionSamuel Thibault
* hurd/Versions (GLIBC_2.4): Remove __stack_chk_fail. * mach/Versions (GLIBC_2.4): Remove __stack_chk_fail.
2017-08-28hurd: Fix typoSamuel Thibault
* hurd/Versions: Fix typo. * mach/Versions: Fix typo.
2017-08-28<bits/syscall.h>: Use an arch-independent system call list on LinuxFlorian Weimer
This commit changes the way the list of SYS_* system call macros is created on Linux. glibc now contains a list of all known system calls, and the generated <bits/syscall.h> file defines the SYS_ macro only if the correspnding __NR_ macro is defined by the kernel headers. As a result, glibc does not have to be rebuilt to pick up system calls if the glibc sources already know about them. This means that glibc can be built with older kernel headers, and if the installed kernel headers are upgraded afterwards, additional SYS_ macros become available as long as glibc has a record for those system calls.