Remove libc-modules.h from the tree and auto-generate it from
soversions.i and the list of modules in the built-modules variable
defined in Makeconfig. Macros generated have increasing numbered
values, with built-modules having lower values starting from 1,
following which a separator value LIBS_BEGIN is added and then finally
the library names from soversions.i are appended to the list. This
allows us to conveniently differentiate between the versioned
libraries and other built modules, which is needed in errno.h and
netdb.h to decide whether to use an internal symbol or an external
one.
Verified that generated code remains unchanged on x86_64.
* Makeconfig (built-modules): List non-library modules to be
built.
(module-cppflags): Include libc-modules.h for
everything except shlib-versions.v.i.
(CPPFLAGS): Use it.
(before-compile): Add libc-modules.h.
($(common-objpfx)libc-modules.h,
$(common-objpfx)libc-modules.stmp): New targets.
(common-generated): Add libc-modules.h and libc-modules.stmp.
($(common-objpfx)Versions.v.i): Depend on libc-modules.h.
* include/libc-symbols.h: Don't include libc-modules.h.
* include/libc-modules.h: Remove file.
* scripts/gen-libc-modules.awk: New script to generate
libc-modules.h.
* sysdeps/unix/Makefile ($(common-objpfx)sysd-syscalls):
Depend on libc-modules.stmp.
The current scheme to identify which module a translation unit is
built in depends on defining multiple macros IS_IN_* and also defining
NOT_IN_libc if we're building a non-libc module. In addition, there
is an IN_LIB macro that does effectively the same thing, but for
different modules (notably the systemtap probes). This macro scheme
unifies both ideas to use just one macro IN_MODULE and assign it a
value depending on the module it is being built into. If the module
is not defined, it defaults to MODULE_libc.
Patches that follow will replace uses of IS_IN_* variables with the
IS_IN() macro. libc-symbols.h has been converted already to give an
example of how such a transition will look.
Verified that there are no relevant binary changes. One source change
that will crop up repeatedly is that of nscd_stat, since it uses the
build timestamp as a constant in its logic.
* Makeconfig (in-module): Get value of libof set for the
translation unit.
(CPPFLAGS): Use $(in-module).
* Makerules: Don't suffix routine names for nonlib.
* include/libc-modules.h: New file.
* include/libc-symbols.h: Include libc-modules.h
(IS_IN): New macro to replace IS_IN_* macros.
* elf/Makefile: Set libof-* for each routine.
* elf/rtld-Rules: Likewise.
* extra-modules.mk: Likewise.
* iconv/Makefile: Likewise.
* iconvdata/Makefile: Likewise.
* locale/Makefile: Likewise.
* malloc/Makefile: Likewise.
* nss/Makefile: Likewise.
* sysdeps/gnu/Makefile: Likewise.
* sysdeps/ieee754/ldbl-opt/Makefile: Likewise.
* sysdeps/unix/sysv/linux/Makefile: Likewise.
* sysdeps/s390/s390-64/Makefile: Likewise.
* nscd/Makefile: Set libof-* for each routine. Set CFLAGS and
CPPFLAGS for nscd instead of nonlib.
This patch makes the installed signal.h declare __sigpause only when
necessary (when a macro definition of sigpause makes use of
__sigpause), rather than unconditionally. This fixes false positives
in the linknamespace tests by making it visible to those tests that no
use of ISO C functionality will actually bring in the definition of
__sigpause and so bring in the other symbols defined in the same
object. There is no bug filed in Bugzilla because this is fixing
false positives rather than any user-visible bug.
Tested for x86_64 (testsuite, and that installed stripped shared
libraries are unchanged by this patch).
* signal/signal.h (__sigpause): Only declare if [__USE_XOPEN &&
!__GNUC__].
* include/signal.h (__sigpause): Move declaration above call to
libc_hidden_proto.
* conform/Makefile (test-xfail-ISO/signal.h/linknamespace): Remove
variable.
(test-xfail-ISO99/signal.h/linknamespace): Likewise.
(test-xfail-ISO11/signal.h/linknamespace): Likewise.
This patch fixes the build of C mempcpy and stpcpy by disabling the
redirection to __mempcpy and __stpcpy asm names if
NO_MEMPCPY_STPCPY_REDIRECT is defined, and defining that macro in the
relevant source files.
Tested for powerpc32 that the build is fixed.
* include/string.h [NO_MEMPCPY_STPCPY_REDIRECT] (mempcpy): Do not
redeclare with asm name.
[NO_MEMPCPY_STPCPY_REDIRECT] (stpcpy): Likewise.
* string/mempcpy.c (NO_MEMPCPY_STPCPY_REDIRECT): Define before
including <string.h>.
* string/stpcpy.c (NO_MEMPCPY_STPCPY_REDIRECT): Likewise.
* sysdeps/powerpc/powerpc32/power4/multiarch/mempcpy.c
[!NOT_IN_libc] (NO_MEMPCPY_STPCPY_REDIRECT): Likewise.
* sysdeps/powerpc/powerpc64/multiarch/mempcpy.c
[!NOT_IN_libc] (NO_MEMPCPY_STPCPY_REDIRECT): Likewise.
* sysdeps/powerpc/powerpc64/multiarch/stpcpy.c
[SHARED && !NOT_IN_libc] (NO_MEMPCPY_STPCPY_REDIRECT): Likewise.
Locale code, brought in by ISO C functions, calls memmem, which is not
an ISO C function. This isn't an ISO C conformance bug, because all
mem* names are reserved, but glibc practice is not to rely on that
reservation (thus, memmem is only declared in string.h if __USE_GNU
even though ISO C would allow it to be declared unconditionally, for
example). This patch changes that code to use __memmem.
Note: there are uses of memmem elsewhere in glibc that I didn't
change, although it may turn out some of those also need to use
__memmem.
Tested for x86_64 (testsuite, and that disassembly of installed shared
libraries is unchanged by this patch).
[BZ #17585]
* string/memmem.c [!_LIBC] (__memmem): Define to memmem.
(memmem): Rename to __memmem and define as weak alias of
__memmem. Use libc_hidden_weak.
(__memmem): Use libc_hidden_def.
* include/string.h (__memmem): Declare. Use libc_hidden_proto.
* locale/findlocale.c (valid_locale_name): Use __memmem instead of
memmem.
__get_nprocs is called from malloc code, but calls fgets_unlocked,
which is not an ISO C or POSIX function. This patch fixes it to call
a new __fgets_unlocked name instead.
Note: there are various other uses of fgets_unlocked in glibc's
libraries, and I haven't yet investigated which others might also be
problematic (called directly or indirectly from standard functions)
and so need to change to use __fgets_unlocked.
Tested for x86_64 (testsuite, and that disassembly of installed shared
libraries is unchanged by the patch).
[BZ #17582]
* libio/iofgets.c [weak_alias && !_IO_MTSAFE_IO]
(__fgets_unlocked): Add alias of _IO_fgets. Use libc_hidden_def.
* libio/iofgets_u.c (fgets_unlocked): Rename to __fgets_unlocked
and define as weak alias of __fgets_unlocked. Use
libc_hidden_weak.
(__fgets_unlocked): Use libc_hidden_def.
* include/stdio.h (__fgets_unlocked): Declare. Use
libc_hidden_proto.
* sysdeps/unix/sysv/linux/getsysstats.c (phys_pages_info): Use
__fgets_unlocked instead of fgets_unlocked.
* sysdeps/unix/sysv/linux/alpha/getsysstats.c
(GET_NPROCS_CONF_PARSER): Likewise.
* sysdeps/unix/sysv/linux/sparc/getsysstats.c
(GET_NPROCS_CONF_PARSER): Likewise.
__printf_fp calls wmemset, but that is not an ISO C90 function. This
patch fixes it to call a new __wmemset name instead (with wmemset
being a weak alias).
Tested for x86_64 (testsuite, and that disassembly of installed shared
libraries is unchanged by the patch).
[BZ #17574]
* wcsmbs/wmemset.c (wmemset): Rename to __wmemset and define as
weak alias of __wmemset. Use libc_hidden_weak.
(__wmemset): Use libc_hidden_def.
* include/wchar.h (__wmemset): Declare. Use libc_hidden_proto.
* stdio-common/printf_fp.c (___printf_fp): Call __wmemset instead
of wmemset.
Various glibc functions call __stpcpy and __mempcpy for namespace
reasons instead of plain stpcpy and mempcpy. But __stpcpy and
__mempcpy are macros that call __builtin_stpcpy and __builtin_mempcpy,
and unless GCC optimizes the calls, they end up calling the C
functions stpcpy and mempcpy.
For calls from within shared libc, libc_hidden_builtin_proto ensures
that calls to those C functions are in turn mapped to call __GI_stpcpy
and __GI_mempcpy. However, for static libc, and for calls from shared
libraries other than libc, the ELF symbols stpcpy and mempcpy end up
getting called, breaking the ISO C namespace (in the case of stpcpy)
or glibc conventions about not relying on the "future library
directions" reservations (in the case of mempcpy).
This patch fixes this by adding declarations of these functions to
include/string.h, under an appropriate condition, with __asm__ used to
change the assembler name used for calls (the mempcpy case was
previously discussed, and the approach for the fix is as I suggested
in <https://sourceware.org/ml/libc-alpha/2013-02/msg00063.html>).
Tested for x86_64 with the testsuite; also checked that dcigettext.o
(an example previously noted of undesired calls to stpcpy and mempcpy)
now calls __stpcpy and __mempcpy instead, as do non-libc shared
libraries (__stpcpy and __mempcpy were already exported from shared
libc). Disassembly of installed shared libraries isn't easy to
compare because of reordered PLT entries resulting from the change in
functions called (libnsl, libnss_compat, libnss_dns, libnss_files,
libnss_hesiod, libnss_nis, libnss_nisplus, libpthread, librt all have
such changes).
[BZ #17573]
* include/string.h [NOT_IN_libc || !SHARED] (mempcpy): Declare
with asm name __mempcpy.
[NOT_IN_libc || !SHARED] (stpcpy): Declare with asm name __stpcpy.
qsort_r is defined in the same file as qsort, but is not an ISO C
function, so should be a weak alias for __qsort_r. The uses in
getaddrinfo should also call __qsort_r, since getaddrinfo is a POSIX
function and qsort_r isn't. This patch implements this. Because nscd
uses the getaddrinfo sources outside libc, as do the tst-rfc3484
tests, a #define of __qsort_r to qsort_r is added there alongside the
similar defines for other libc-internal symbols used in getaddrinfo.
Tested for x86_64 (testsuite, and that disassembly of installed shared
libraries is unchanged by the patch).
[BZ #17571]
* stdlib/msort.c (qsort_r): Rename to __qsort_r and define as weak
alias of __qsort_r.
(qsort): Call __qsort_r instead of qsort_r.
* include/stdlib.h (qsort_r): Do not call libc_hidden_proto.
(__qsort_r): Declare. Call libc_hidden_proto.
* sysdeps/posix/getaddrinfo.c (getaddrinfo): Call __qsort_r
instead of qsort_r.
* nscd/gai.c (__qsort_r): Define to qsort_r.
* posix/tst-rfc3484.c (__qsort_r): Likewise.
* posix/tst-rfc3484-2.c (__qsort_r): Likewise.
* posix/tst-rfc3484-3.c (__qsort_r): Likewise.
__getcwd is called from dcigettext.o (brought in by various ISO C
functionality), but calls rewinddir, which is not an ISO C function.
This patch makes __getcwd call __rewinddir instead and makes rewinddir
a weak alias for __rewinddir.
Since getcwd.c is shared with gnulib (albeit not merged in either
direction for a long time, and omitted from gnulib's
config/srclist.txt list of shared files) I put in a #ifndef _LIBC
define of __rewinddir to rewinddir, although a future merged version
of getcwd could end up looking significantly different.
Tested for x86_64 (testsuite, and that disassembly of installed shared
libraries is unchanged by this patch).
[BZ #17584]
* dirent/rewinddir.c (rewinddir): Rename to __rewinddir and define
as weak alias of __rewinddir. Don't use libc_hidden_def.
(__rewinddir): Use libc_hidden_def.
* sysdeps/mach/hurd/rewinddir.c: Rename to __rewinddir and define
as weak alias of __rewinddir. Don't use libc_hidden_def.
(__rewinddir): Use libc_hidden_def.
* sysdeps/posix/rewinddir.c: Rename to __rewinddir and define as
weak alias of __rewinddir. Don't use libc_hidden_def.
(__rewinddir): Use libc_hidden_def.
* include/dirent.h (rewinddir): Don't use libc_hidden_proto.
(__rewinddir): Use libc_hidden_proto.
* sysdeps/posix/getcwd.c [!_LIBC] (__rewinddir): Define to
rewinddir.
(__getcwd): Use __rewinddir instead of rewinddir.
tzfile.c is brought in by various ISO C functions, but calls fileno,
fread_unlocked and ftello, which are not ISO C functions. This patch
adds names __fileno, __fread_unlocked and __ftello for those
functions, making tzfile.c use those new names.
Note: there are various uses of fileno elsewhere in glibc that I
didn't change, although it may turn out that some of those also need
to use __fileno.
Tested for x86_64 with the glibc testsuite. Changed line numbers in
tzfile.c cause changes in assertions, and for some reason this ends up
with different instruction choice and register allocation, affecting
the size of __tzfile_read and so making comparison of disassembly for
libc.so problematic.
[BZ #17583]
* libio/fileno.c (fileno): Rename to __fileno and define as weak
alias of __fileno. Use libc_hidden_weak.
(__fileno): Use libc_hidden_def.
[weak_alias] (fileno_unlocked): Define as weak alias of __fileno.
* libio/ftello.c (ftello): Rename to __ftello and define as weak
alias of __ftello.
[__OFF_T_MATCHES_OFF64_T] (ftello64): Define as weak alias of
__ftello.
* libio/iofread.c [weak_alias && !_IO_MTSAFE_IO]
(__fread_unlocked): Define as strong alias of _IO_fread. Use
libc_hidden_def.
(fread_unlocked): Don't use libc_hidden_ver.
* libio/iofread_u.c (fread_unlocked): Rename to __fread_unlocked
and define as weak alias of __fread_unlocked. Don't use
libc_hidden_def.
(__fread_unlocked): Use libc_hidden_def.
* include/stdio.h (__fileno): Declare. Use libc_hidden_proto.
(ftello): Don't use libc_hidden_proto.
(__ftello): Declare. Use libc_hidden_proto.
(fread_unlocked): Don't use libc_hidden_proto.
(__fread_unlocked): Declare. Use libc_hidden_proto.
* time/tzfile.c (__tzfile_read): Use __fileno, __fread_unlocked
and __ftello instead of fileno, fread_unlocked and ftello.
Continuing the removal of unused __libc_* function names, this patch
removes the __libc_waitpid name.
Tested for x86_64 (testsuite, and that disassembly of installed shared
libraries is unchanged by the patch; __waitpid, which is exported from
shared libc, changes from weak to strong on some configurations, which
is of no significance).
* include/sys/wait.h (__libc_waitpid): Remove declaration.
* posix/waitpid.c (__libc_waitpid): Rename to __waitpid.
(__waitpid): Don't define as alias. Use libc_hidden_def not
libc_hidden_weak.
(waitpid): Define as alias of __waitpid.
* sysdeps/unix/bsd/waitpid.c (__libc_waitpid): Rename to
__waitpid.
(__waitpid): Don't define as alias. Use libc_hidden_def not
libc_hidden_weak.
(waitpid): Define as alias of __waitpid.
* sysdeps/unix/sysv/linux/i386/syscalls.list (waitpid): Remove
__libc_waitpid alias.
* sysdeps/unix/sysv/linux/m68k/syscalls.list (waitpid): Likewise.
* sysdeps/unix/sysv/linux/powerpc/syscalls.list (waitpid):
Likewise.
* sysdeps/unix/sysv/linux/sh/syscalls.list (waitpid): Likewise.
* sysdeps/unix/sysv/linux/sparc/syscalls.list (waitpid): Likewise.
* sysdeps/unix/sysv/linux/tile/waitpid.S (__libc_waitpid): Remove
alias.
* sysdeps/unix/sysv/linux/waitpid.c (__libc_waitpid): Rename to
__waitpid.
(__waitpid): Don't define as alias. Use libc_hidden_def not
libc_hidden_weak.
(waitpid): Define as alias of __waitpid.
Completing the removal of the obsolete INTDEF / INTUSE mechanism, this
patch removes the final use - that for _dl_starting_up - replacing it
by rtld_hidden_def / rtld_hidden_proto. Having removed the last use,
the mechanism itself is also removed.
Tested for x86_64 that installed stripped shared libraries are
unchanged by the patch. (This is not much of a test since this
variable is only defined and used in the !HAVE_INLINED_SYSCALLS case.)
[BZ #14132]
* include/libc-symbols.h (INTUSE): Remove macro.
(INTDEF): Likewise.
(INTVARDEF): Likewise.
(_INTVARDEF): Likewise.
(INTDEF2): Likewise.
(INTVARDEF2): Likewise.
* elf/rtld.c [!HAVE_INLINED_SYSCALLS] (_dl_starting_up): Use
rtld_hidden_def instead of INTVARDEF.
* sysdeps/generic/ldsodefs.h [IS_IN_rtld]
(_dl_starting_up_internal): Remove declaration.
(_dl_starting_up): Use rtld_hidden_proto.
* elf/dl-init.c [!HAVE_INLINED_SYSCALLS] (_dl_starting_up): Remove
declaration.
[!HAVE_INLINED_SYSCALLS] (_dl_starting_up_internal): Likewise.
(_dl_init) [!HAVE_INLINED_SYSCALLS]: Don't use INTUSE with
_dl_starting_up.
* elf/dl-writev.h (_dl_writev): Likewise.
* sysdeps/powerpc/powerpc64/dl-machine.h [!HAVE_INLINED_SYSCALLS]
(DL_STARTING_UP_DEF): Use __GI__dl_starting_up instead of
_dl_starting_up_internal.
Continuing the removal of __libc_* function names that are no longer
used anywhere, this patch removes the __libc_readv and __libc_writev
names.
Tested for x86_64 that stripped installed shared libraries are
unchanged by the patch.
* include/sys/uio.h (__libc_readv): Remove declaration.
(__libc_writev): Likewise.
* misc/readv.c (__libc_readv): Rename to __readv.
(__readv): Do not define as alias.
(readv): Define as alias of __readv.
* misc/writev.c (__libc_writev): Rename to __writev.
(__writev): Do not define as alias.
(writev): Define as alias of __writev.
* sysdeps/posix/readv.c (__libc_readv): Rename to __readv.
(__readv): Do not define as alias.
(readv): Define unconditionally as alias of __readv.
* sysdeps/posix/writev.c (__libc_writev): Rename to __writev.
(__writev): Do not define as alias.
(writev): Define unconditionally as alias of __writev.
* sysdeps/unix/syscalls.list (readv): Do not define __libc_readv
name.
(writev): Do not define __libc_writev name.
glibc has lots of __libc_* function names that no longer serve any
purpose (are not used for any calls or exported at a public symbol
version). This patch removes __libc_creat. It has the effect of
creat becoming a strong symbol instead of a weak symbol in various
cases, but that's fine; in shared libraries it doesn't matter at all,
while for static linking the only other symbol sometimes defined in
the same object is creat64, and whenever creat64 is a reserved name so
is creat.
Other such cases of unnecessary __libc_* symbols are expected to be
dealt with in separate patches over time.
Tested for x86_64 (testsuite, and that the disassembly of installed
shared libraries is unchanged by the patch).
* include/fcntl.h (__libc_creat): Remove declaration.
* io/creat.c (__libc_creat): Rename to creat.
(creat): Do not define as alias.
* sysdeps/unix/sysv/linux/alpha/creat.c (creat64): Define as alias
of creat instead of __libc_creat.
* sysdeps/unix/sysv/linux/generic/creat.c (__libc_creat): Rename
to creat.
(creat): Do not define as alias.
[__WORDSIZE == 64] (creat64): Define as alias of creat instead of
__libc_creat.
* sysdeps/unix/sysv/linux/syscalls.list (creat): Do not define
__libc_creat name.
* sysdeps/unix/sysv/linux/wordsize-64/syscalls.list (creat):
Likewise.
Continuing the removal of the obsolete INTDEF / INTVARDEF / INTUSE
mechanism, this patch replaces its use for __libc_enable_secure with
the use of rtld_hidden_data_def and rtld_hidden_proto.
Tested for x86_64 that installed stripped shared libraries are
unchanged by the patch.
[BZ #14132]
* elf/dl-sysdep.c (__libc_enable_secure): Use rtld_hidden_data_def
instead of INTVARDEF.
(_dl_sysdep_start): Do not use INTUSE with __libc_enable_secure.
* sysdeps/mach/hurd/dl-sysdep.c (__libc_enable_secure): Use
rtld_hidden_data_def instead of INTVARDEF.
(_dl_sysdep_start): Do not use INTUSE with __libc_enable_secure.
* elf/dl-deps.c (expand_dst): Likewise.
* elf/dl-load.c (_dl_dst_count): Likewise.
(_dl_dst_substitute): Likewise.
(decompose_rpath): Likewise.
(_dl_init_paths): Likewise.
(open_path): Likewise.
(_dl_map_object): Likewise.
* elf/rtld.c (dl_main): Likewise.
(process_dl_audit): Likewise.
(process_envvars): Likewise.
* include/unistd.h [IS_IN_rtld] (__libc_enable_secure_internal):
Remove declaration.
(__libc_enable_secure): Use rtld_hidden_proto.
This patch removes use of the obsolete INTDEF/INTUSE mechanism for
__cxa_atexit, replacing it with libc_hidden_def/libc_hidden_proto.
Tested for x86_64 that installed stripped shared libraries are
unchanged by the patch.
[BZ #14132]
* stdlib/cxa_atexit.c (__cxa_atexit): Use libc_hidden_def instead
of INTDEF.
* include/stdlib.h (__cxa_atexit_internal): Remove declaration.
(__cxa_atexit): Use libc_hidden_proto.
[!NOT_IN_libc] (__cxa_atexit): Remove macro definition.
This patch removes some stray (unused) *_internal aliases, and
function prototypes with no corresponding definitions at all, at least
some of which were missed in previous INTDEF / INTUSE removal.
Not removed in this patch: __canonicalize_directory_name_internal,
noticed in the course of preparing this patch, isn't an alias, but an
actual function in sysdeps/mach/hurd/getcwd.c - apparently unused,
however.
Tested for x86_64 that installed stripped shared libraries are
unchanged by this patch.
[BZ #14132]
* include/wctype.h [!_ISOMAC] (__iswalpha_l_internal): Remove
declaration.
[!_ISOMAC] (__iswdigit_l_internal): Likewise.
[!_ISOMAC] (__iswspace_l_internal): Likewise.
[!_ISOMAC] (__iswxdigit_l_internal): Likewise.
[!_ISOMAC] (__iswctype_internal): Likewise.
* stdio-common/siglist.c (_sys_siglist_internal): Remove alias.
* sysdeps/unix/syscalls.list (chown): Remove __chown_internal
alias.
(fcntl): Remove __fcntl_internal alias.
* sysdeps/unix/sysv/linux/hppa/syscalls.list (connect): Remove
__connect_internal alias.
* sysdeps/unix/sysv/linux/sparc/sparc64/syscalls.list (connect):
Likewise.
Fixes -Wundef warnings for MBSTATE_T and HAVE_STRING_H. The
HAVE_STRING_H bit is a merge from the gnulib fnmatch.c and the
MBSTATE_T fix has been posted to gnulib for inclusion.
This patch cleans up for __ASSUME_ATFCTS now always being true for the
supported Linux kernel versions by removing conditional code in
sysdeps/unix/sysv/linux. Several fchownat.c files that were only
present because of differences in the fallback syscalls used
(depending on the architecture-specific names of chown-related
syscalls for 32-bit uids) are removed. Files that looks like they
could be replaced by syscalls.list entries have the standard "Consider
moving to syscalls.list." comment (see bug 14138) added. Conditionals
on the relevant __NR_* syscall numbers being defined are also removed,
since my analysis indicated that the relevant syscalls are always
defined for all relevant kernel versions using any affected file.
Much of the removed fallback code had unbounded stack allocations, so
this reduces the number of cases to consider for anyone reviewing uses
of alloca and VLAs in glibc.
There remain tests of __ASSUME_ATFCTS in io/openat.c (to determine
whether to define __have_atfcts) and sysdeps/posix/getcwd.c (which
also uses __have_atfcts); thus, the definition of __ASSUME_ATFCTS
remains in kernel-features.h. The logical condition relevant there is
whether openat64_not_cancel_3 is known to work. Hurd doesn't use this
version of getcwd at all, so the conditionals in getcwd.c are always
true in glibc. However, this code is also used in gnulib. So the
best way to deal with the conditionals there may be for gnulib people
to deal with merging all relevant changes in both directions between
the glibc and gnulib versions of this file, at the end of which the
openat conditionals should be in whatever form is best for gnulib, and
hardcoded in the _LIBC case to having openat supported.
Tested by comparing before-and-after disassembly of installed
(stripped) shared libraries, on x86_64 and x86. On x86 the patch made
no change to the disassembly; on x86_64, the only changes were in
readlinkat, where formerly the return value from the readlinkat
syscall was stored in an int variable before being converted to
ssize_t for the return, and now the return value is returned directly
without truncation to int. I think it's clearly correct not to
truncate the return value (although I also think the truncation would
not have been a user-visible bug because the kernel would never have
returned a value it could have affected).
* include/fcntl.h (__atfct_seterrno): Remove prototype.
(__atfct_seterrno_2): Likewise.
* sysdeps/unix/sysv/linux/alpha/dl-fxstatat64.c: Do not include
<kernel-features.h>.
(__ASSUME_ATFCTS): Do not undefine and redefine.
* sysdeps/unix/sysv/linux/alpha/fxstatat.c [__ASSUME_ATFCTS]
(__have_atfcts): Remove conditional definition.
(__fxstatat([__NR_fstatat64]: Make code unconditional.
(__fxstatat) [!__ASSUME_ATFCTS]: Remove conditional code and code
unreachable if [__ASSUME_ATFCTS].
* sysdeps/unix/sysv/linux/dl-fxstatat64.c (__ASSUME_ATFCTS): Do
not undefine and redefine.
* sysdeps/unix/sysv/linux/faccessat.c: Do not include
<kernel-features.h>.
(faccessat) [__NR_faccessat]: Make code unconditional.
(faccessat) [!__ASSUME_ATFCTS]: Remove conditional code.
* sysdeps/unix/sysv/linux/fchmodat.c: Do not include
<kernel-features.h>.
(fchmodat) [__NR_fchmodat]: Make code unconditional.
(fchmodat) [!__ASSUME_ATFCTS]: Remove conditional code.
* sysdeps/unix/sysv/linux/fchownat.c: Do not include
<kernel-features.h>.
(fchownat) [__NR_fchownat]: Make code unconditional.
(fchownat) [!__ASSUME_ATFCTS]: Remove conditional code.
* sysdeps/unix/sysv/linux/futimesat.c: Do not include
<kernel-features.h>.
(futimesat) [__NR_futimesat]: Make code unconditional.
(futimesat) [!__ASSUME_ATFCTS]: Remove conditional code.
* sysdeps/unix/sysv/linux/fxstatat.c: Do not include
<kernel-features.h>.
(__fxstatat) [__NR_newfstatat]: Make code unconditional.
(__fxstatat) [!__ASSUME_ATFCTS]: Remove conditional code.
* sysdeps/unix/sysv/linux/fxstatat64.c: Do not include
<kernel-features.h>.
(__fxstatat64) [__NR_fstatat64]: Make code unconditional.
(__fxstatat64) [!__ASSUME_ATFCTS]: Remove conditional code.
* sysdeps/unix/sysv/linux/i386/fchownat.c: Remove file.
* sysdeps/unix/sysv/linux/i386/fxstatat.c: Do not include
<kernel-features.h>.
(__fxstatat) [__NR_fstatat64]: Make code unconditional.
(__fxstatat) [!__ASSUME_ATFCTS]: Remove conditional code.
* sysdeps/unix/sysv/linux/linkat.c: Do not include
<kernel-features.h>.
(linkat) [__NR_linkat]: Make code unconditional.
(linkat) [!__ASSUME_ATFCTS]: Remove conditional code.
* sysdeps/unix/sysv/linux/m68k/fchownat.c: Remove file.
* sysdeps/unix/sysv/linux/mips/mips64/fxstatat64.c: Do not include
<kernel-features.h>.
(__fxstatat64) [__NR_newfstatat]: Make code unconditional.
(__fxstatat64) [!__ASSUME_ATFCTS]: Remove conditional code.
* sysdeps/unix/sysv/linux/mkdirat.c: Do not include
<kernel-features.h>.
(mkdirat) [__NR_mkdirat]: Make code unconditional.
(mkdirat) [!__ASSUME_ATFCTS]: Remove conditional code.
* sysdeps/unix/sysv/linux/openat.c: Do not include
<kernel-features.h>.
[!__ASSUME_ATFCTS] (__atfct_seterrno): Remove function.
[!__ASSUME_ATFCTS] (__have_atfcts): Remove variable.
(OPENAT_NOT_CANCEL) [__NR_openat]: Make code unconditional.
(OPENAT_NOT_CANCEL) [!__ASSUME_ATFCTS]: Remove conditional code.
* sysdeps/unix/sysv/linux/powerpc/fchownat.c: Remove file.
* sysdeps/unix/sysv/linux/readlinkat.c: Do not include
<kernel-features.h>.
(readlinkat) [__NR_readlinkat]: Make code unconditional.
(readlinkat) [!__ASSUME_ATFCTS]: Remove conditional code. Return
result of INLINE_SYSCALL directly, not via int variable.
* sysdeps/unix/sysv/linux/renameat.c: Do not include
<kernel-features.h>.
[!__ASSUME_ATFCTS] (__atfct_seterrno_2): Remove function.
(renameat) [__NR_renameat]: Make code unconditional.
(renameat) [!__ASSUME_ATFCTS]: Remove conditional code.
* sysdeps/unix/sysv/linux/s390/s390-32/fchownat.c: Remove file.
* sysdeps/unix/sysv/linux/sh/fchownat.c: Remove file.
* sysdeps/unix/sysv/linux/sparc/sparc32/fchownat.c: Remove file.
* sysdeps/unix/sysv/linux/sparc/sparc64/dl-fxstatat64.c
(__ASSUME_ATFCTS): Do not undefine and redefine.
* sysdeps/unix/sysv/linux/symlinkat.c: Do not include
<kernel-features.h>.
(symlinkat) [__NR_symlinkat]: Make code unconditional.
(symlinkat) [!__ASSUME_ATFCTS]: Remove conditional code.
* sysdeps/unix/sysv/linux/unlinkat.c: Do not include
<kernel-features.h>.
(unlinkat) [__NR_unlinkat]: Make code unconditional.
(unlinkat) [!__ASSUME_ATFCTS]: Remove conditional code.
* sysdeps/unix/sysv/linux/wordsize-64/dl-fxstatat64.c
(__ASSUME_ATFCTS): Do not undefine and redefine.
* sysdeps/unix/sysv/linux/wordsize-64/fxstatat.c: Do not include
<kernel-features.h>.
(__fxstatat) [__NR_newfstatat]: Make code unconditional.
(__fxstatat) [!__ASSUME_ATFCTS]: Remove conditional code.
* sysdeps/unix/sysv/linux/xmknodat.c: Do not include
<kernel-features.h>.
(__xmknodat) [__NR_mknodat]: Make code unconditional.
(__xmknodat) [!__ASSUME_ATFCTS]: Remove conditional code.
Source packages that need to support both 2.19 and
2.20 will need to decide to use _BSD_SOURCE and
_SVID_SOURCE vs. _DEFAULT_SOURCE.
The difficulty in making that decision is that
__GLIBC_MINOR__ is itself defined in features.h,
but you want to set the feature test macros before
including features.h.
Therefore to ease the transition we should disable
the warning if _DEFAULT_SOURCE is also defined.
https://sourceware.org/ml/libc-alpha/2014-02/msg00666.htmlhttps://sourceware.org/glibc/wiki/Release/2.20#Packaging_Changes
This is a minimal patch to remove _BSD_SOURCE and _SVID_SOURCE from
the documented user API, making them into aliases for _DEFAULT_SOURCE
with a #warning given, but keeping most of the features.h logic using
those macros and all the exising __USE_* conditionals, on the basis
that all the consequent cleanups will go in followup patches.
Tested x86_64.
* include/features.h: Update comment documenting feature test
macros.
[_BSD_SOURCE || _SVID_SOURCE]: Give #warning. Define
_DEFAULT_SOURCE.
* manual/creature.texi (_BSD_SOURCE): Remove documentation.
(_SVID_SOURCE): Likewise.
(_DEFAULT_SOURCE): Update description of default features.
(Feature Test Macros): Don't mention _SVID_SOURCE in conjunction
with _GNU_SOURCE.
* manual/filesys.texi (__ftw_func_t): Do not refer to _BSD_SOURCE.
(S_ISVTX): Likewise.
* manual/math.texi (Mathematical Constants): Likewise.
* manual/signal.texi (Interrupted Primitives): Likewise.
* manual/startup.texi (putenv): Do not refer to _SVID_SOURCE.
* math/test-matherr.c (_SVID_SOURCE): Do not define.
* sysvipc/sys/ipc.h [__USE_SVID && !__USE_XOPEN && __GNUC__ >= 2]:
Don't refer to _SVID_SOURCE in warning text.
Add a comment pointing to the SystemTap wiki page that documents the
format of the arguments. Also add a pointer to the SystemTap and
gdb sources which seem to be the best place to get the architecture
specific details.
ChangeLog:
2014-02-11 Will Newton <will.newton@linaro.org>
* include/stap-probe.h: Add comment about probe argument
format.
This patch adds a feature test macro _DEFAULT_SOURCE to enable the
default set of header declarations.
The intention is: if _DEFAULT_SOURCE is not used there is no change to
the set of __USE_* macros glibc defines; if it's used on its own, and
without compiler options such as -std=c99 that define __STRICT_ANSI__,
again, there is no change; if it's used together with the macros it
approximately (i.e., apart from __USE_POSIX_IMPLICITLY) implies
(-D_BSD_SOURCE -D_SVID_SOURCE -D_POSIX_C_SOURCE=200809L), again, there
is no change. Otherwise, it causes the relevant features to be
enabled, even if __STRICT_ANSI__, or another feature test macro, would
cause them to be disabled.
This macro deliberately bundles the POSIX.1-2008 (non-X/Open)
functionality with the BSD/SVID/"misc" functionality, rather than
defining a macro that gives just the latter, as many of the header
cleanups resulting from removing _BSD_SOURCE and _SVID_SOURCE support
are only possible when BSD/SVID/"misc" is always bundled with
POSIX.1-2008.
Tested x86_64.
* include/features.h: Update comment documenting feature test
macros. Mention _DEFAULT_SOURCE in comment.
[_GNU_SOURCE] (_DEFAULT_SOURCE): Undefine and redefine.
[_DEFAULT_SOURCE]: Undefine and redefine _DEFAULT_SOURCE,
_BSD_SOURCE and _SVID_SOURCE.
[!__STRICT_ANSI__ && !_ISOC99_SOURCE && !_POSIX_SOURCE &&
!_POSIX_C_SOURCE && !_XOPEN_SOURCE && !_BSD_SOURCE &&
!_SVID_SOURCE]: Likewise.
[_DEFAULT_SOURCE && !_POSIX_SOURCE && !_POSIX_C_SOURCE]
(__USE_POSIX_IMPLICITLY): Define.
[_DEFAULT_SOURCE && !_POSIX_SOURCE && !_POSIX_C_SOURCE]
(_POSIX_SOURCE): Undefine and redefine.
[_DEFAULT_SOURCE && !_POSIX_SOURCE && !_POSIX_C_SOURCE]
(_POSIX_C_SOURCE): Likewise.
* manual/creature.texi (_DEFAULT_SOURCE): Document.
(Feature Test Macros): Update documentation of default features.
Joseph pointed out in the bug report (and in an earlier thread) that
systemtap probes cause build time warnings like the following:
../sysdeps/ieee754/dbl-64/e_atan2.c:602:4: warning: the address of
'p' will always evaluate as 'true' [-Waddress]
due to the fact that we're now passing non-weak variables to
LIBC_PROBE in the libm probes. This happens only on configurations
that do not enable systemtap. The macro definition of LIBC_PROBE in
this case only acts as a sanity checker to ensure that the number
parameters passed to LIBC_PROBE is equal to the argument count
parameter passed before it. This can be done in a much simpler manner
by just adding a macro definition for each number of arguments. I am
assuming here that we don't really want to bother with supporting
LIBC_PROBE with an indeterminate number of arguments and if there is a
need for a probe to have more data than what is currently supported (4
arguments), one could simply add an additional macro here.
