A recent change to libio/tst-ftell-active-handler.c (postdating my
last check for warnings on x86) introduced a format warning from a
long int variable used with a %zu format. This patch fixes it by
using %ld for the format to match the variable.
Tested for x86.
* libio/tst-ftell-active-handler.c (do_ftruncate_test): Use %ld
format for long int variable.
On 'do_ftell_test' the code:
365 if (test_modes[i].fd_mode != O_WRONLY)
366 {
367 char tmpbuf[data_len];
368
369 rewind (fp);
370
371 while (fgets_func (tmpbuf, sizeof (tmpbuf), fp) && !feof (fp));
The 'data_len' is calculated with wsclen and allocated as 'char'. The
subsequent fgetws will then try to write at most 'data_len' wchar_t
in a buffer with just data_len 'char'. This patch fixes it by
allocating the tmpbuf using 'wchar_t' * data_len bytes.
POSIX allows applications to switch file handles when a read results
in an end of file. Unset the cached offset at this point so that it
is queried again.
The test case fails to truncate the file when a file is intended to be
opened in w or w+ mode. Add O_TRUNC to fix this. The test still
succeeds with this change.
Currently we seek to end of file if there are unflushed writes or the
stream is in write mode, to get the current offset for writing in
append mode, which is the end of file. The latter case (i.e. stream
is in write mode, but no unflushed writes) is unnecessary since it
will only happen when the stream has just been flushed, in which case
the recorded offset ought to be reliable.
Removing that case lets ftell give the correct offset when it follows
an ftruncate. The latter truncates the file, but does not change the
file position, due to which it is permissible to call ftell without an
intervening fseek call.
Tested on x86_64 to verify that the added test case fails without the
patch and succeeds with it, and that there are no additional
regressions due to it.
[BZ #17647]
* libio/fileops.c (do_ftell): Seek only when there are
unflushed writes.
* libio/wfileops.c (do_ftell_wide): Likewise.
* libio/tst-ftell-active-handler.c (do_ftruncate_test): New
test case.
(do_one_test): Call it.
This patch fixes a warning "variable 'wc' set but not used" in
libio/bug-ungetwc1.c.
The test didn't verify much about the results of the functions it
called. This patch makes it check the result of getwc (thereby fixing
the warning), check end of file does not arrive too late in the getwc
loop, and check EOF is no longer set after ungetwc.
Tested for x86_64.
* libio/bug-ungetwc1.c (do_test): Verify results of getwc and
feof.
This patch fixes "set but not used" warnings in the tests
libio/bug-rewind.c and libio/bug-rewind2.c by checking the return
values from fwscanf and making the tests fail if those values aren't
as expected.
Tested for x86_64.
* libio/bug-rewind.c (do_test): Check fwscanf return values.
* libio/bug-rewind2.c (do_test): Likewise.
__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.
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.
The check for only __GNUC_STDC_INLINE__ and __GNUC_GNU_INLINE__ may
not be sufficient since those flags were added during initial support
for C99 inlining semantics. There is also a problem with always
defining __extern_inline and __extern_always_inline, since it enables
inline wrapper functions even when GNU inlining semantics are not
guaranteed. This, along with the possibility of such wrappers using
redirection (btowc for example) could result in compiler generating an
infinitely recusrive call to the function.
In fact it was such a recursion that led to this code being written
the way it was; see:
https://bugzilla.redhat.com/show_bug.cgi?id=186410
The initial change was to fix bugs 14530 and 13741, but they can be
resolved by checking if __fortify_function and/or
__extern_always_inline are defined, as it has been done in this patch.
In addition, I have audited uses of __extern_always_inline to make
sure that none of the uses result in compilation errors.
There is however a regression in this patch for llvm, since it reverts
the llvm expectation that __GNUC_STDC_INLINE__ or __GNUC_GNU_INLINE__
definition imply proper extern inline semantics.
2014-09-16 Siddhesh Poyarekar <siddhesh@redhat.com>
Jakub Jelinek <jakub@redhat.com>
[BZ #17266]
* libio/stdio.h: Check definition of __fortify_function
instead of __extern_always_inline to include bits/stdio2.h.
* math/bits/math-finite.h [__USE_XOPEN || __USE_ISOC99]: Also
check if __extern_always_inline is defined.
[__USE_MISC || __USE_XOPEN]: Likewise.
[__USE_ISOC99] Likewise.
* misc/sys/cdefs.h (__fortify_function): Define only if
__extern_always_inline is defined.
[!__cplusplus || __GNUC_PREREQ (4,3)]: Revert to defining
__extern_always_inline and __extern_inline only for g++-4.3
and newer or a compatible gcc.
Prior to the 2.20 release, the function was just changed to fail
unconditionally, in commit a1a6a401ab.
This commit removes the function completely, including gconv bits
which depend on it.
This changes the gconv ABI, which is not a public interface.
Various glibc build / install / test code has C locale settings that
are redundant with LC_ALL=C.
LC_ALL takes precedence over LANG, so anywhere that sets LC_ALL=C
(explicitly, or through it being in the default environment for
running tests) does not need to set LANG=C. LC_ALL=C also takes
precedence over LANGUAGE, since
2001-01-02 Ulrich Drepper <drepper@redhat.com>
* intl/dcigettext.c (guess_category_value): Rewrite so that LANGUAGE
value is ignored if the selected locale is the C locale.
* intl/tst-gettext.c: Set locale for above change.
* intl/tst-translit.c: Likewise.
and so settings of LANGUAGE=C are also redundant when LC_ALL=C is
set. One test also had LC_ALL=C in its -ENV setting, although it's
part of the default environment used for tests.
This patch removes the redundant settings. It removes a suggestion in
install.texi of setting LANGUAGE=C LC_ALL=C for "make install"; the
Makefile.in target "install" already sets LC_ALL_C so there's no need
for the user to set it (and nor should there be any need for the user
to set it).
If some build machine tool used by "make install" uses a version of
libintl predating that 2001 change, and the user has LANGUAGE set, the
removal of LANGUAGE=C from the Makefile.in "install" rule could in
principle affect the user's installation. However, I don't think we
need to be concerned about pre-2001 build tools.
Tested x86_64.
* Makefile (install): Don't set LANGUAGE.
* Makefile.in (install): Likewise.
* assert/Makefile (test-assert-ENV): Remove variable.
(test-assert-perr-ENV): Likewise.
* elf/Makefile (neededtest4-ENV): Likewise.
* iconvdata/Makefile ($(inst_gconvdir)/gconv-modules)
[$(cross-compiling) = no]: Don't set LANGUAGE.
* io/ftwtest-sh (LANG): Remove variable.
* libio/Makefile (tst-widetext-ENV): Likewise.
* manual/install.texi (Running make install): Don't refer to
environment settings for make install.
* INSTALL: Regenerated.
* nptl/tst-tls6.sh: Don't set LANG.
* posix/globtest.sh (LANG): Remove variable.
* string/Makefile (tester-ENV): Likewise.
(inl-tester-ENV): Likewise.
(noinl-tester-ENV): Likewise.
* sysdeps/s390/s390-64/Makefile ($(inst_gconvdir)/gconv-modules)
[$(cross-compiling) = no]: Don't set LANGUAGE.
* timezone/Makefile (build-testdata): Use $(built-program-cmd)
without explicit environment settings.
localedata/ChangeLog:
* tst-fmon.sh: Don't set LANGUAGE.
* tst-locale.sh: Likewise.
Tests run using the default $(make-test-out) automatically get
GCONV_PATH and LC_ALL set, whether or not those environment variables
are actually needed for the individual test. However, they do not get
LOCPATH set, meaning that a large number of tests have -ENV settings
just to set LOCPATH.
This patch moves LOCPATH into the default environment used for all
tests, on the principle that like GCONV_PATH any settings needed to
use files associated with the newly built library, rather than any old
installed files, are appropriate to use by default.
A further motivation is that various tests using .sh files also set
some combination of LC_ALL, GCONV_PATH and LOCPATH. Preferably .sh
files should also use the default environment with any additions
required for the individual test. Now, it was suggested in
<https://sourceware.org/ml/libc-alpha/2014-05/msg00715.html> that
various Makefile variables used in testing should be derived by
composing the -before-env and -after-env variables used when explicit
environment settings are required. With such a change, it's also
natural for those variables to include the default settings (via some
intermediate makefile variable also used in make-test-out).
Because some .sh files only set variables that correspond to the
default settings, or a subset thereof, and this applies to more of the
.sh files once LOCPATH is in the default settings, doing so reduces
the size of a revised version of
<https://sourceware.org/ml/libc-alpha/2014-05/msg00596.html>: scripts
only needing the (expanded) default settings will not need to receive
the separate -before-env and -after-env variables, only the single
variable they do at present. So moving LOCPATH into the default
settings can reduce churn caused by subsequent patches.
Tested x86_64 and x86.
* Rules (make-test-out): Include
LOCPATH=$(common-objpfx)localedata in default environment.
* debug/Makefile (tst-chk1-ENV): Remove variable.
(tst-chk2-ENV): Likewise.
(tst-chk3-ENV): Likewise.
(tst-chk4-ENV): Likewise.
(tst-chk5-ENV): Likewise.
(tst-chk6-ENV): Likewise.
(tst-lfschk1-ENV): Likewise.
(tst-lfschk2-ENV): Likewise.
(tst-lfschk3-ENV): Likewise.
(tst-lfschk4-ENV): Likewise.
(tst-lfschk5-ENV): Likewise.
(tst-lfschk6-ENV): Likewise.
* iconvdata/Makefile (bug-iconv6-ENV): Likewise.
(tst-iconv7-ENV): Likewise.
* intl/Makefile (LOCPATH-ENV): Likewise.
(tst-codeset-ENV): Likewise.
(tst-gettext3-ENV): Likewise.
(tst-gettext5-ENV): Likewise.
* libio/Makefile (tst-widetext-ENV): Don't set LOCPATH.
(tst-fopenloc-ENV): Likewise.
(tst-fgetws-ENV): Remove variable.
(tst-ungetwc1-ENV): Likewise.
(tst-ungetwc2-ENV): Likewise.
(bug-ungetwc2-ENV): Likewise.
(tst-swscanf-ENV): Likewise.
(bug-ftell-ENV): Likewise.
(tst-fgetwc-ENV): Likewise.
(tst-fseek-ENV): Likewise.
(tst-ftell-partial-wide-ENV): Likewise.
(tst-ftell-active-handler-ENV): Likewise.
(tst-ftell-append-ENV): Likewise.
* posix/Makefile (tst-fnmatch-ENV): Likewise.
(tst-regexloc-ENV): Likewise.
(bug-regex1-ENV): Likewise.
(tst-regex-ENV): Likewise.
(tst-regex2-ENV): Likewise.
(bug-regex5-ENV): Likewise.
(bug-regex6-ENV): Likewise.
(bug-regex17-ENV): Likewise.
(bug-regex18-ENV): Likewise.
(bug-regex19-ENV): Likewise.
(bug-regex20-ENV): Likewise.
(bug-regex22-ENV): Likewise.
(bug-regex23-ENV): Likewise.
(bug-regex25-ENV): Likewise.
(bug-regex26-ENV): Likewise.
(bug-regex30-ENV): Likewise.
(bug-regex32-ENV): Likewise.
(bug-regex33-ENV): Likewise.
(bug-regex34-ENV): Likewise.
(bug-regex35-ENV): Likewise.
(tst-rxspencer-ENV): Likewise.
(tst-rxspencer-no-utf8-ENV): Likewise.
* stdio-common/Makefile (tst-sprintf-ENV): Likewise.
(tst-sscanf-ENV): Likewise.
(tst-swprintf-ENV): Likewise.
(tst-swscanf-ENV): Likewise.
(test-vfprintf-ENV): Likewise.
(scanf13-ENV): Likewise.
(bug14-ENV): Likewise.
(tst-grouping-ENV): Likewise.
* stdlib/Makefile (tst-strtod-ENV): Likewise.
(tst-strtod3-ENV): Likewise.
(tst-strtod4-ENV): Likewise.
(tst-strtod5-ENV): Likewise.
(testmb2-ENV): Likewise./
* string/Makefile (tst-strxfrm-ENV): Likewise.
(tst-strxfrm2-ENV): Likewise.
(bug-strcoll1-ENV): Likewise.
(test-strcasecmp-ENV): Likewise.
(test-strncasecmp-ENV): Likewise.
* time/Makefile (tst-strptime-ENV): Likewise.
(tst-ftime_l-ENV): Likewise.
* wcsmbs/Makefile (tst-btowc-ENV): Likewise.
(tst-mbrtowc-ENV): Likewise.
(tst-wcrtomb-ENV): Likewise.
(tst-mbrtowc2-ENV): Likewise.
(tst-c16c32-1-ENV): Likewise.
(tst-mbsnrtowcs-ENV): Likewise.
localedata/ChangeLog:
* Makefile (TEST_MBWC_ENV): Remove variable.
(tst_iswalnum-ENV): Likewise.
(tst_iswalpha-ENV): Likewise.
(tst_iswcntrl-ENV): Likewise.
(tst_iswctype-ENV): Likewise.
(tst_iswdigit-ENV): Likewise.
(tst_iswgraph-ENV): Likewise.
(tst_iswlower-ENV): Likewise.
(tst_iswprint-ENV): Likewise.
(tst_iswpunct-ENV): Likewise.
(tst_iswspace-ENV): Likewise.
(tst_iswupper-ENV): Likewise.
(tst_iswxdigit-ENV): Likewise.
(tst_mblen-ENV): Likewise.
(tst_mbrlen-ENV): Likewise.
(tst_mbrtowc-ENV): Likewise.
(tst_mbsrtowcs-ENV): Likewise.
(tst_mbstowcs-ENV): Likewise.
(tst_mbtowc-ENV): Likewise.
(tst_strcoll-ENV): Likewise.
(tst_strfmon-ENV): Likewise.
(tst_strxfrm-ENV): Likewise.
(tst_swscanf-ENV): Likewise.
(tst_towctrans-ENV): Likewise.
(tst_towlower-ENV): Likewise.
(tst_towupper-ENV): Likewise.
(tst_wcrtomb-ENV): Likewise.
(tst_wcscat-ENV): Likewise.
(tst_wcschr-ENV): Likewise.
(tst_wcscmp-ENV): Likewise.
(tst_wcscoll-ENV): Likewise.
(tst_wcscpy-ENV): Likewise.
(tst_wcscspn-ENV): Likewise.
(tst_wcslen-ENV): Likewise.
(tst_wcsncat-ENV): Likewise.
(tst_wcsncmp-ENV): Likewise.
(tst_wcsncpy-ENV): Likewise.
(tst_wcspbrk-ENV): Likewise.
(tst_wcsrtombs-ENV): Likewise.
(tst_wcsspn-ENV): Likewise.
(tst_wcsstr-ENV): Likewise.
(tst_wcstod-ENV): Likewise.
(tst_wcstok-ENV): Likewise.
(tst_wcstombs-ENV): Likewise.
(tst_wcswidth-ENV): Likewise.
(tst_wcsxfrm-ENV): Likewise.
(tst_wctob-ENV): Likewise.
(tst_wctomb-ENV): Likewise.
(tst_wctrans-ENV): Likewise.
(tst_wctype-ENV): Likewise.
(tst_wcwidth-ENV): Likewise.
(tst-digits-ENV): Likewise.
(tst-mbswcs6-ENV): Likewise.
(tst-xlocale1-ENV): Likewise.
(tst-xlocale2-ENV): Likewise.
(tst-strfmon1-ENV): Likewise.
(tst-strptime-ENV): Likewise.
(tst-setlocale-ENV): Don't set LOCPATH.
(bug-iconv-trans-ENV): Remove variable.
(tst-sscanf-ENV): Likewise.
(tst-leaks-ENV): Don't set LOCPATH.
(bug-setlocale1-ENV): Remove variable.
(bug-setlocale1-static-ENV): Likewise.
(tst-setlocale2-ENV): Likewise.
The offset computation in write mode uses the fact that _IO_read_end
is kept in sync with the external file offset. This however is not
true when O_APPEND is in effect since switching to write mode ought to
send the external file offset to the end of file without making the
necessary adjustment to _IO_read_end.
Hence in append mode, offset computation when writing should only
consider the effect of unflushed writes, i.e. from _IO_write_base to
_IO_write_ptr.
The wiki has a detailed document that describes the rationale for
offsets returned by ftell in various conditions:
https://sourceware.org/glibc/wiki/File%20offsets%20in%20a%20stdio%20stream%20and%20ftell
ChangeLog:
2014-03-17 Will Newton <will.newton@linaro.org>
* libio/genops.c: Check whether
_IO_JUMPS_OFFSET is defined with #ifdef rather
than #if.
* libio/libioP.h: Likewise.
* stdio-common/vfprintf.c: Likewise.
fdopen should only be allowed to change the offset in the file it
attaches to if it is setting O_APPEND. If O_APPEND is already set, it
should not change the state of the handle.
The ftell implementation was made conservative to ensure that
incorrectly cached offsets never affect it. However, this causes
problems for append mode when a file stream is rewound. Additionally,
the 'clever' trick of using stat to get position for append mode files
caused more problems than it solved and broke old behavior. I have
described the various problems that it caused and then finally the
solution.
For a and a+ mode files, rewinding the stream should result in ftell
returning 0 as the offset, but the stat() trick caused it to
(incorrectly) always return the end of file. Now I couldn't find
anything in POSIX that specifies the stream position after rewind()
for a file opened in 'a' mode, but for 'a+' mode it should be set to
0. For 'a' mode too, it probably makes sense to keep it set to 0 in
the interest of retaining old behavior.
The initial file position for append mode files is implementation
defined, so the implementation could either retain the current file
position or move the position to the end of file. The earlier ftell
implementation would move the offset to end of file for append-only
mode, but retain the old offset for a+ mode. It would also cache the
offset (this detail is important). My patch broke this and would set
the initial position to end of file for both append modes, thus
breaking old behavior. I was ignorant enough to write an incorrect
test case for it too.
The Change:
I have now brought back the behavior of seeking to end of file for
append-only streams, but with a slight difference. I don't cache the
offset though, since we would want ftell to query the current file
position through lseek while the stream is not active. Since the
offset is moved to the end of file, we can rely on the file position
reported by lseek and we don't need to resort to the stat() nonsense.
Finally, the cache is always reliable, except when there are unflished
writes in an append mode stream (i.e. both a and a+). In the latter
case, it is safe to just do an lseek to SEEK_END. The value can be
safely cached too, since the file handle is already active at this
point. Incidentally, this is the only state change we affect in the
file handle (apart from taking locks of course).
I have also updated the test case to correct my impression of the
initial file position for a+ streams to the initial behavior. I have
verified that this does not break any existing tests in the testsuite
and also passes with the new tests.
The test functions used a variable ret to store failure codes for
individual tests, but the variable was incorrectly used to record
other failure codes too, resulting in overwriting of the tests status.
This is now fixed by making sure that the ret variable is used only
for recording test failures.
* libio/tst-ftell-active-handler.c (do_ftell_test): Don't mix
up test status with function return status.
(do_write_test): Likewise.
(do_append_test): Likewise.
This patch is a revised and updated version of
<https://sourceware.org/ml/libc-alpha/2014-01/msg00196.html>.
In order to generate overall summaries of the results of all tests in
the glibc testsuite, we need to identify and concatenate the files
with the results of individual tests.
Tomas Dohnalek's patch used $(common-objpfx)*/*.test-result for this.
However, the normal glibc approach is explicit enumeration of the
expected set of files with a given property, rather than all files
matching some pattern like that. Furthermore, we would like to be
able to mark tests as UNRESOLVED if the file with their results is for
some reason missing, and in future we would like to be able to mark
tests as UNSUPPORTED if they are disabled for a particular
configuration (rather than simply having them missing from the list of
tests as at present). Such handling of tests that were not run or did
not record results requires an explicit enumeration of tests.
For the tests following the default makefile rules, $(tests) (and
$(xtests)) provides such an enumeration. Others, however, are added
directly as dependencies of the "tests" and "xtests" makefile
targets. This patch changes the makefiles to put them in variables
tests-special and xtests-special, with appropriate dependencies on the
tests listed there then being added centrally.
Those variables are used in Rules and so need to be set before Rules
is included in a subdirectory makefile, which is often earlier in the
makefile than the dependencies were present before. We previously
discussed the question of where to include Rules; see the question at
<https://sourceware.org/ml/libc-alpha/2012-11/msg00798.html>, and a
discussion in
<https://sourceware.org/ml/libc-alpha/2013-01/msg00337.html> of why
Rules is included early rather than late in subdirectory makefiles.
It was necessary to avoid an indirection through the check-abi target
and get the check-abi-* targets for individual libraries into the
tests-special variable. The intl/ test $(objpfx)tst-gettext.out,
previously built only because of dependencies from other tests, was
also added to tests-special for the same reason.
The entries in tests-special are the full makefile targets, complete
with $(objpfx) and .out. If a future change causes tests to be named
consistently with a .out suffix, this can be changed to include just
the path relative to $(objpfx), without .out.
Tested x86_64, including that the same set of files is generated in
the build directory by a build and testsuite run both before and after
the patch (except for changes to the
elf/tst-null-argv.debug.out.<number> file name), and a build with
run-built-tests=no to verify there aren't any more obvious instances
of the issue Marcus Shawcroft reported with a previous version in
<https://sourceware.org/ml/libc-alpha/2014-01/msg00462.html>.
* Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
(tests): Depend on $(tests-special).
* Makerules (check-abi-list): New variable.
(check-abi): Depend on $(check-abi-list).
[$(subdir) = elf] (tests-special): Add
$(objpfx)check-abi-libc.out.
[$(build-shared) = yes && subdir] (tests-special): Add
$(check-abi-list).
[$(build-shared) = yes && subdir] (tests): Do not depend on
check-abi.
* Rules (tests): Depend on $(tests-special).
(xtests): Depend on $(xtests-special).
* catgets/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* conform/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* elf/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* grp/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* iconv/Makefile (xtests): Change dependencies to ....
(xtests-special): ... additions to this variable.
* iconvdata/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* intl/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable. Also add
$(objpfx)tst-gettext.out.
* io/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* libio/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* malloc/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* misc/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* nptl/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* nptl_db/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* posix/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
(xtests): Change dependencies to ....
(xtests-special): ... additions to this variable.
* resolv/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
(xtests): Change dependencies to ....
(xtests-special): ... additions to this variable.
* stdio-common/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
(do-tst-unbputc): Remove target.
(do-tst-printf): Likewise.
* stdlib/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* string/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* sysdeps/x86/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
localedata:
* Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
The cached offset is reliable to use in ftell when the stream handle
is active. We can consider a stream as being active when there is
unflushed data. However, even in this case, we can use the cached
offset only when the stream is not being written to in a+ mode,
because this case may have unflushed data and a stale offset; the
previous read could have sent it off somewhere other than the end of
the file.
There were a couple of adjustments necessary to get this to work.
Firstly, fdopen now ceases to use _IO_attach_fd because it sets the
offset cache to the current file position. This is not correct
because there could be changes to the file descriptor before the
stream handle is activated, which would not get reflected.
A similar offset caching action is done in _IO_fwide, claiming that
wide streams have 'problems' with the file offsets. There don't seem
to be any obvious problems with not having the offset cache available,
other than that it will have to be queried in a subsequent
read/write/seek. I have removed this as well.
The testsuite passes successfully with these changes on x86_64.
ftell semantics are distinct from fseek(SEEK_CUR) especially when it
is called on a file handler that is not yet active. Due to this
caveat, much care needs to be taken while modifying the handler data
and hence, this first iteration on separating out ftell focusses on
maintaining handler data integrity at all times while it figures out
the current stream offset. The result is that it makes a syscall for
every offset request.
There is scope for optimizing this by caching offsets when we know
that the handler is active. A simple way to find out is when the
buffers have data. It is not so simple to find this out when the
buffer is empty without adding some kind of flag.
In <https://sourceware.org/ml/libc-alpha/2014-01/msg00196.html> I
noted it was necessary to add includes of Makeconfig early in various
subdirectory makefiles for the tests-special variable settings added
by that patch to be conditional on configuration information. No-one
commented on the general question there of whether Makeconfig should
always be included immediately after the definition of subdir.
This patch implements that early inclusion of Makeconfig in each
directory (which is a lot easier than consistent placement of includes
of Rules). Includes are added if needed, or moved up if already
present. Subdirectory "all:" targets are removed, since Makeconfig
provides one.
There is potential for further cleanups I haven't done. Rules and
Makerules have code such as
ifneq "$(findstring env,$(origin headers))" ""
headers :=
endif
to override to empty any value of various variables that came from the
environment. I think there is a case for Makeconfig setting all the
subdirectory variables (other than subdir) to empty to ensure no
outside value is going to take effect if a subdirectory fails to
define a variable. (A list of such variables, possibly out of date
and incomplete, is in manual/maint.texi.) Rules and Makerules would
give errors if Makeconfig hadn't already been included, instead of
including it themselves. The special code to override values coming
from the environment would then be obsolete and could be removed.
Tested x86_64, including that installed binaries are identical before
and after the patch.
* argp/Makefile: Include Makeconfig immediately after defining
subdir.
* assert/Makefile: Likewise.
* benchtests/Makefile: Likewise.
* catgets/Makefile: Likewise.
* conform/Makefile: Likewise.
* crypt/Makefile: Likewise.
* csu/Makefile: Likewise.
(all): Remove target.
* ctype/Makefile: Include Makeconfig immediately after defining
subdir.
* debug/Makefile: Likewise.
* dirent/Makefile: Likewise.
* dlfcn/Makefile: Likewise.
* gmon/Makefile: Likewise.
* gnulib/Makefile: Likewise.
* grp/Makefile: Likewise.
* gshadow/Makefile: Likewise.
* hesiod/Makefile: Likewise.
* hurd/Makefile: Likewise.
(all): Remove target.
* iconvdata/Makefile: Include Makeconfig immediately after
defining subdir.
* inet/Makefile: Likewise.
* intl/Makefile: Likewise.
* io/Makefile: Likewise.
* libio/Makefile: Likewise.
(all): Remove target.
* locale/Makefile: Include Makeconfig immediately after defining
subdir.
* login/Makefile: Likewise.
* mach/Makefile: Likewise.
(all): Remove target.
* malloc/Makefile: Include Makeconfig immediately after defining
subdir.
(all): Remove target.
* manual/Makefile: Include Makeconfig immediately after defining
subdir.
* math/Makefile: Likewise.
* misc/Makefile: Likewise.
* nis/Makefile: Likewise.
* nss/Makefile: Likewise.
* po/Makefile: Likewise.
(all): Remove target.
* posix/Makefile: Include Makeconfig immediately after defining
subdir.
* pwd/Makefile: Likewise.
* resolv/Makefile: Likewise.
* resource/Makefile: Likewise.
* rt/Makefile: Likewise.
* setjmp/Makefile: Likewise.
* shadow/Makefile: Likewise.
* signal/Makefile: Likewise.
* socket/Makefile: Likewise.
* soft-fp/Makefile: Likewise.
* stdio-common/Makefile: Likewise.
* stdlib/Makefile: Likewise.
* streams/Makefile: Likewise.
* string/Makefile: Likewise.
* sunrpc/Makefile: Likewise.
(all): Remove target.
* sysvipc/Makefile: Include Makeconfig immediately after defining
subdir.
* termios/Makefile: Likewise.
* time/Makefile: Likewise.
* timezone/Makefile: Likewise.
(all): Remove target.
* wcsmbs/Makefile: Include Makeconfig immediately after defining
subdir.
* wctype/Makefile: Likewise.
libidn/ChangeLog:
* Makefile: Include Makeconfig immediately after defining subdir.
localedata/ChangeLog:
* Makefile: Include Makeconfig immediately after defining subdir.
(all): Remove target.
nptl/ChangeLog:
* Makefile: Include Makeconfig immediately after defining subdir.
nptl_db/ChangeLog:
* Makefile: Include Makeconfig immediately after defining subdir.
Most glibc tests that use mtrace to verify that there were no memory
leaks from the glibc facilities used in a given test depend on the
.out file of the previous test so that the mtrace test runs mtrace and
nothing else.
Two, however, have a single target combining mtrace with something
else. In the case of libio/tst-fopenloc.check, the test both compares
the output with an expected baseline and runs mtrace. In the case of
posix/tst-rxspencer-mem, the test is run (with different command line
from the main run) and then mtrace is run, from the same makefile
target.
This patch splits both of these tests up to use separate makefile
targets for each thing tested; in the tst-rxspencer case, a file
tst-rxspencer-no-utf8.c is created that just includes tst-rxspencer.c,
as is usual for tests where the same code gets tested in different
compile-time or runtime configurations.
Adding $(evaluate-test) to test commands, as in
<https://sourceware.org/ml/libc-alpha/2014-01/msg00194.html>, will no
longer need to insert && between multiple commands, as all tests will
either have just a single command or already use &&.
Tested x86_64.
* libio/Makefile ($(objpfx)tst-fopenloc.check): Split into
separate $(objpfx)tst-fopenloc-cmp.out and
$(objpfx)tst-fopenloc-mem.out targets.
(tests): Update dependencies.
* posix/Makefile (tests variable): Add tst-rxspencer-no-utf8.
(generated): Change tst-rxspencer-mem and tst-rxspencer.mtrace to
tst-rxspencer-no-utf8-mem and tst-rxspencer-no-utf8.mtrace.
(tst-rxspencer-no-utf8-ARGS): New variable.
(tst-rxspencer-no-utf8-ENV): Likewise.
(tests target): Depend on $(objpfx)tst-rxspencer-no-utf8-mem
instead of $(objpfx)tst-rxspencer-mem.
($(objpfx)tst-rxspencer-mem): Change target to
$(objpfx)tst-rxspencer-no-utf8-mem. Depend on
$(objpfx)tst-rxspencer-no-utf8.out instead of running test program.
* posix/tst-rxspencer-no-utf8.c: New file.
This patch cleans up cases of __USE_MISC that are trivially redundant
after the recent substitution of __USE_MISC for __USE_BSD and
__USE_SVID: either in constructs such as "defined __USE_MISC ||
defined __USE_MISC", or else (in the bits/mman.h case) a conditional
on __USE_MISC nested inside another __USE_MISC conditional. (The
cleanups remaining after this patch are still quite large, but it
seems a reasonable piece to separate out.)
Tested x86_64.
* bits/mman.h [__USE_MISC]: Remove redundant conditionals.
* ctype/ctype.h [__USE_MISC]: Likewise.
* dirent/dirent.h [__USE_MISC]: Likewise.
* grp/grp.h [__USE_MISC]: Likewise.
* io/fcntl.h [__USE_MISC]: Likewise.
* io/sys/stat.h [__USE_MISC]: Likewise.
* libio/stdio.h [__USE_MISC]: Likewise.
* posix/unistd.h [__USE_MISC]: Likewise.
* pwd/pwd.h [__USE_MISC]: Likewise.
* stdlib.h [__USE_MISC]: Likewise.
* string/bits/string2.h [__USE_MISC]: Likewise.
* string/string.h [__USE_MISC]: Likewise.
* time/time.h [__USE_MISC]: Likewise.
ftell tries to avoid flushing the buffer when it is in write mode by
converting the wide char data and placing it into the binary buffer.
If the output buffer space is full and there is data to write, the
code reverts to flushing the buffer. This breaks when there is space
in the buffer but it is not enough to convert the next character in
the wide data buffer, due to which __codecvt_do_out returns a
__codecvt_partial status. In this case, ftell keeps running in an
infinite loop.
The fix here is to detect the __codecvt_partial status in addition to
checking if the buffer is full. I have also added a test case that
demonstrates the infinite loop.
Partially revert commits 2b766585f9 and
de2fd463b1, which were intended to fix BZ#11741
but caused another, likely worse bug, namely that fwrite() and fputs() could,
in an error path, read data beyond the end of the specified buffer, and
potentially even write this data to the file.
Fix BZ#11741 properly by checking the return value from _IO_padn() in
stdio-common/vfprintf.c.
Fixes 15381.
Using wide character function is on byte oriented memstream is undefined
behaviour. This behaviour was masked by not initializing wide struct
info. We now initialize it to cause a predictable crash.
In BZ #12724, partial support for POSIX 2008 fclose behavior was added.
Since it isn't entirely conforming to the spec, some applications are
known to be breaking in this intermediate state. So revert the partial
support until we can get things fully implemented.
This reverts commit fcabc0f8b1.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
[BZ #14543]
Set the internal buffer state correctly whenever the external buffer
state is modified by fseek by either computing the current
_IO_read_ptr/end for the internal buffer based on the new _IO_read_ptr
in the external buffer or converting the content read into the
external buffer, up to the extent of the requested fseek offset.
[BZ #11959]
* libio/stdio.h (fwrite, fwrite_unlocked): Remove __wur.
It is not necessarily an error to ignore fwrite's return
value. One can reliably use ferror to test for errors after
the fact.
fopen should set the FD_CLOEXEC flag if requested evenif the kernel does
not support an aotmic operation.
freopen should reuse the file descriptor for the stream. This is
especially important for calls to change the standard streams (stin,
stdout, stderr).
* libio/wfileops.c (_IO_wfile_underflow): Fix handling of
incomplete characters at end of input buffer.
* libio/Makefile (tests): Add tst-fgetwc.
* libio/tst-fgetwc.c: New file.
* libio/tst-fgetwc.input: New file.
* libio/fmemopen.c: Implement binary mode. In this mode no NUL
byte gets added to writes and seeks from the end use the length of
the buffer and not the currently terminating NUL byte.
file descriptors with close-on-exec set.
(exec_comm_child): Fix the case where the write end of the pipe is
STDOUT_FILENO already. In case it is, clear close-on-exec.
* time/tzset.c (tzset_internal): Break TZ string parsing out into
__tzset_parse_tz and updating of daylight, timezone, tzname into
update_vars.
(__tz_compute): Renamed from tz_compute. Take additional parameters.
(__tz_convert): Updating of tm_isdst, tm_zone, and tm_gmtoff now
happens in __tz_compute.
* time/tzfile.c (__tzfile_read): Also read TZ string.
(find_transition): Fold into __tzfile_compute.
(__tzfile_compute): For times beyond the last transition try to
use the TZ string.
* timezone/tst-timezone.c: Information in daylight and tzname does
change for Asia/Tokyo timezone with more concrete information.
Remove the test.
* include/stdio.h: Add libc_hidden_proto for ftello.
* libio/ftello.c: Add libc_hidden_def.
with __warning__/__error__ attributes.
(__warnattr): Define.
* stdlib/bits/stdlib.h (__realpath_chk_warn, __ptsname_r_chk_warn,
__mbstowcs_chk_warn, __wcstombs_chk_warn): New aliases with
__warnattr.
(realpath, ptsname_r, mbstowcs, wcstombs): Call __*_chk_warn instead
of __*_chk if compile time detectable overflow is found.
* libio/bits/stdio2.h (__fgets_chk_warn, __fread_chk_warn,
__fgets_unlocked_chk_warn, __fread_unlocked_chk_warn): New aliases
with __warnattr.
(fgets, fread, fgets_unlocked, fread_unlocked): Call __*_chk_warn
instead of __*_chk if compile time detectable overflow is found.
(__gets_alias): Rename to...
(__gets_warn): ... this. Add __warnattr.
(gets): Call __gets_warn instead of __gets_alias.
* socket/bits/socket2.h (__recv_chk_warn, __recvfrom_chk_warn): New
aliases with __warnattr.
(recv, recvfrom): Call __*_chk_warn instead of __*_chk if compile
time detectable overflow is found.
* posix/bits/unistd.h (__read_chk_warn, __pread_chk_warn,
__pread64_chk_warn, __readlink_chk_warn, __readlinkat_chk_warn,
__getcwd_chk_warn, __confstr_chk_warn, __getgroups_chk_warn,
__ttyname_r_chk_warn, __getlogin_r_chk_warn, __gethostname_chk_warn,
__getdomainname_chk_warn): New aliases with __warnattr.
(read, pread, pread64, readlink, readlinkat, getcwd, confstr,
getgroups, ttyname_r, getlogin_r, gethostname, getdomainname): Call
__*_chk_warn instead of __*_chk if compile time detectable overflow
is found.
(__getgroups_chk): Rename argument to __listlen from listlen.
(__getwd_alias): Rename to...
(__getwd_warn): ... this. Add __warnattr.
(getwd): Call __getwd_warn instead of __getwd_alias.
* wcsmbs/bits/wchar2.h (__wmemcpy_chk_warn, __wmemmove_chk_warn,
__wmempcpy_chk_warn, __wmemset_chk_warn, __wcsncpy_chk_warn,
__wcpncpy_chk_warn, __fgetws_chk_warn, __fgetws_unlocked_chk_warn,
__mbsrtowcs_chk_warn, __wcsrtombs_chk_warn, __mbsnrtowcs_chk_warn,
__wcsnrtombs_chk_warn): New aliases with __warnattr.
(wmemcpy, wmemmove, wmempcpy, wmemset, mbsrtowcs, wcsrtombs,
mbsnrtowcs, wcsnrtombs): Call __*_chk_warn instead of __*_chk if
compile time detectable overflow is found.
(wcsncpy, wcpncpy): Likewise. For constant __n fix check whether
to use __*_chk or not.
(fgetws, fgetws_unlocked): Divide __bos by sizeof (wchar_t), both
in comparisons which function should be called and in __*_chk*
arguments. Call __*_chk_warn instead of __*_chk if compile time
detectable overflow is found.
(swprintf, vswprintf): Divide __bos by sizeof (wchar_t) in
__*_chk argument.
* debug/tst-chk1.c (do_test): Add a few more tests.
* misc/bits/syslog.h (syslog): When __va_arg_pack is defined,
implement as __extern_always_inline function.
(vsyslog): Define as __extern_always_inline function unconditionally.
* libio/bits/stdio2.h (sprintf, snprintf, printf, fprintf):
When __va_arg_pack is defined, implement as __extern_always_inline
functions.
(vsprintf, vsnprintf, vprintf, vfprintf): Define as
__extern_always_inline functions unconditionally.
* libio/bits/stdio.h (vprintf): Ifdef out the inline when
bits/stdio2.h will be included.
* wcsmbs/bits/wchar2.h (__swprintf_alias): New redirect.
(swprintf, wprintf, fwprintf): When __va_arg_pack is defined,
implement as __extern_always_inline functions.
(vswprintf, vwprintf, vfwprintf): Define as
__extern_always_inline functions unconditionally.
* debug/tst-chk1.c (do_test): Enable remaining tests for C++.
2007-09-03 Jakub Jelinek <jakub@redhat.com>
* misc/sys/cdefs.h (__extern_inline, __extern_always_inline): Only
define in C++ for GCC 4.3+, in C++ always use __gnu_inline__
attribute.
* include/features.h (__USE_EXTERN_INLINES): Define only when
__extern_inline is defined.
* stdlib/stdlib.h: Include bits/stdlib.h when __extern_always_inline
is defined instead of when not __cplusplus.
* misc/sys/syslog.h: Include bits/syslog.h when __extern_always_inline
is defined instead of when not __cplusplus.
* socket/sys/socket.h: Include bits/socket2.h when
__extern_always_inline is defined instead of when not __cplusplus.
* libio/stdio.h: Include bits/stdio2.h when __extern_always_inline
is defined instead of when not __cplusplus.
* posix/unistd.h: Include bits/unistd.h when __extern_always_inline
is defined instead of when not __cplusplus.
* string/string.h: Include bits/string3.h when __extern_always_inline
is defined instead of when not __cplusplus.
* wcsmbs/wchar.h: Include bits/wchar2.h when __extern_always_inline
is defined instead of when not __cplusplus.
(btowc, wctob): Don't guard the inlines with ifndef __cplusplus.
* io/fcntl.h: Don't include bits/fcntl2.h if __extern_always_inline
is not defined.
* misc/bits/syslog-ldbl.h: Guard *_chk stuff with
defined __extern_always_inline instead of !defined __cplusplus.
* libio/bits/stdio-ldbl.h: Likewise.
* wcsmbs/bits/wchar-ldbl.h: Likewise.
* misc/bits/syslog.h (syslog): Don't define for C++.
(vsyslog): Use __extern_always_inline function for C++ instead of
a macro.
* libio/bits/stdio.h (__STDIO_INLINE): Define to __extern_inline
whenever that macro is defined.
(vprintf): Don't provide the inline for C++.
(fread_unlocked, fwrite_unlocked): Don't define the macros for C++.
* libio/bits/stdio2.h (sprintf, snprintf, printf, fprintf): Don't
define the macros for C++.
(vsprintf, vsnprintf, vprintf, vfprintf): Define as
__extern_always_inline functions for C++.
* io/sys/stat.h (stat, lstat, fstat, fstatat, mknod, mknodat,
stat64, lstat64, fstat64, fstatat64): Don't define if not
__USE_EXTERN_INLINES.
* wcsmbs/bits/wchar2.h: Fix #error message.
(swprintf, wprintf, fwprintf): Don't define the macros for C++.
(vswprintf, vwprintf, vfwprintf): Define using
__extern_always_inline functions for C++.
* string/bits/string3.h: Don't #undef macros if __cplusplus.
(memcpy, memmove, mempcpy, memset, bcopy, bzero, strcpy, stpcpy,
strncpy, strcat, strncat): Define as __extern_always_inline
functions instead of macros for C++.
* math/bits/cmathcalls.h: Guard __extern_inline routines with
defined __extern_inline.
* sysdeps/alpha/fpu/bits/mathinline.h (__MATH_INLINE): Define
to __extern_inline whenever that macro is defined.
* sysdeps/ia64/fpu/bits/mathinline.h (__MATH_INLINE): Likewise.
* sysdeps/i386/fpu/bits/mathinline.h (__MATH_INLINE): Likewise.
* sysdeps/i386/i486/bits/string.h (__STRING_INLINE): Likewise.
* sysdeps/s390/bits/string.h (__STRING_INLINE): Likewise.
* sysdeps/s390/fpu/bits/mathinline.h (__MATH_INLINE): Likewise.
* sysdeps/powerpc/fpu/bits/mathinline.h (__MATH_INLINE): Likewise.
* sysdeps/x86_64/fpu/bits/mathinline.h (__MATH_INLINE): Likewise.
* sysdeps/sparc/fpu/bits/mathinline.h (__MATH_INLINE): Likewise.
* sysdeps/unix/sysv/linux/sys/sysmacros.h (gnu_dev_major,
gnu_dev_minor, gnu_dev_makedev): Remove __extern_inline from
prototypes. Only provide __extern_inline routines if
__USE_EXTERN_INLINES.
* debug/Makefile: Add rules to build and run tst-{,lfs}chk{4,5,6}
tests.
* debug/tst-chk1.c (do_prepare, do_test): Allow compilation as C++.
For now avoid some *printf tests in C++. Skip all testing
if __USE_FORTIFY_LEVEL is defined, but __extern_always_inline macro
is not.
* debug/tst-chk4.cc: New file.
* debug/tst-chk5.cc: New file.
* debug/tst-chk6.cc: New file.
* debug/tst-lfschk4.cc: New file.
* debug/tst-lfschk5.cc: New file.
* debug/tst-lfschk6.cc: New file.
* include/wchar.h (__vfwprintf_chk, __vswprintf_chk): Avoid
prototypes in C++.
* include/stdio.h (__sprintf_chk, __snprintf_chk, __vsprintf_chk,
__vsnprintf_chk, __printf_chk, __fprintf_chk, __vprintf_chk,
__vfprintf_chk, __fgets_unlocked_chk, __fgets_chk): Likewise.
* iconv/gconv_cache.c (__gconv_lookup_cache): Return __GCONV_NULCONV
if from and to charsets are the same.
* iconv/gconv_db.c (__gconv_find_transform): Likewise.
* intl/dcigettext.c (_nl_find_msg): Return NULL even if __gconv_open
returns __GCONV_NOCONV, but not for __GCONV_NULCONV.
2007-07-17 Jakub Jelinek <jakub@redhat.com>
* wcsmbs/wchar.h: Only define wint_t if __need_wint_t.
Don't define wint_t when __need_mbstate_t unless it
is necessary.
(__mbstate_t): Use __WINT_TYPE__ rather than wint_t
in the typedef if possible.
* wctype/wctype.h (wint_t): Define by including
wchar.h with __need_wint_t instead of including stddef.h
with __need_wint_t and as fallback definining it ourselves.
* iconv/gconv.h (__need_wint_t): Define before including
wchar.h.
* sysdeps/gnu/_G_config.h: Don't include gconv.h if not _LIBC
or _GLIBCPP_USE_WCHAR_T.
(__need_wchar_t): Don't define
if not _LIBC or _GLIBCPP_USE_WCHAR_T.
(__need_wint_t): Don't define before including stddef.h,
define before including wchar.h only if _LIBC or
_GLIBCPP_USE_WCHAR_T.
(_G_iconv_t): Don't define if not _LIBC or _GLIBCPP_USE_WCHAR_T.
* sysdeps/mach/hurd/_G_config.h: Likewise.
* sysdeps/generic/_G_config.h: Likewise.
* libio/libio.h (__wunderflow, __wuflow, __woverflow): Only
prototype if _LIBC or _GLIBCPP_USE_WCHAR_T.
(_IO_getwc_unlocked, _IO_putwc_unlocked): Only define
if _LIBC or _GLIBCPP_USE_WCHAR_T.
in loop to look for conversion specifier to avoid testing of
wrong errno value.
* stdio-common/Makefile (tests): Add bug18, bug18a, bug19, bug19a.
* stdio-common/bug18a.c: New file.
* stdio-common/bug19.c: New file.
* stdio-common/bug19a.c: New file.
