Copy regex-related files back from Gnulib, to fix a problem with
static checking of regex calls noted by Martin Sebor. This merges the
following changes:
* New macro __attribute_nonnull__ in misc/sys/cdefs.h, for use later
when copying other files back from Gnulib.
* Use __GNULIB_CDEFS instead of __GLIBC__ when deciding
whether to include bits/wordsize.h etc.
* Avoid duplicate entries in epsilon closure table.
* New regex.h macro _REGEX_NELTS to let regexec say that its pmatch
arg should contain nmatch elts. Use that for regexec, instead of
__attr_access (which is incorrect).
* New regex.h macro _Attr_access_ which is like __attr_access except
portable to non-glibc platforms.
* Add some DEBUG_ASSERTs to pacify gcc -fanalyzer and to catch
recently-fixed performance bugs if they recur.
* Add Gnulib-specific stuff to port the dynarray- and lock-using parts
of regex code to non-glibc platforms.
* Fix glibc bug 11053.
* Avoid some undefined behavior when popping an empty fail stack.
(cherry picked from commit 0b5ca7c3e5)
I used these shell commands:
../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright
(cd ../glibc && git commit -am"[this commit message]")
and then ignored the output, which consisted lines saying "FOO: warning:
copyright statement not found" for each of 6694 files FOO.
I then removed trailing white space from benchtests/bench-pthread-locks.c
and iconvdata/tst-iconv-big5-hkscs-to-2ucs4.c, to work around this
diagnostic from Savannah:
remote: *** pre-commit check failed ...
remote: *** error: lines with trailing whitespace found
remote: error: hook declined to update refs/heads/master
* include/intprops.h: Sync from Gnulib. This improves
performance of INT_MULTIPLY_WRAPV on recent GCC, which affects
glibc only in the support library.
[BZ #23603][BZ #16346]
This fixes some obscure problems with integer overflow.
Although it looks scary, it is almost all a byte-for-byte copy
from Gnulib, and the Gnulib code has been tested reasonably well.
* include/intprops.h: New file, copied from Gnulib.
* include/verify.h, time/mktime-internal.h:
New tiny files, simplified from Gnulib.
* time/mktime.c: Copy from Gnulib. This has the following changes:
Do not include config.h if DEBUG_MKTIME is nonzero.
Include stdbool.h, intprops.h, verify.h.
Include string.h only if needed.
Include stdlib.h on MS-Windows.
Include mktime-internal.h.
(DEBUG_MKTIME): Default to 0, and simplify later uses.
(NEED_MKTIME_INTERNAL, NEED_MKTIME_WINDOWS)
(NEED_MKTIME_WORKING): Give default values to pacify -Wundef,
which glibc uses. Default NEED_MKTIME_WORKING to DEBUG_MKTIME, to
simplify later conditionals; default the others to zero. Use
these conditionals to express only the code needed on the current
platform. In uses of these conditionals, explicitly spell out how
_LIBC affects things, so it’s easier to review from a glibc
viewpoint.
(WRAPV): Remove; no longer needed now that we have
systematic overflow checking.
(my_tzset, __tzset) [!_LIBC]: New function and macro, to better
compartmentalize tzset issues. Move system-dependent tzsettish
code here from mktime.
(verify): Remove; now done by verify.h. All uses changed.
(long_int): Use a more-conservative definition, to avoid
integer overflow.
(SHR): Remove, replacing with ...
(shr): New function, which means we needn’t worry about side
effects in args, and conversion analysis is simpler.
(TYPE_IS_INTEGER, TYPE_TWOS_COMPLEMENT, TYPE_SIGNED, TYPE_MINIMUM)
(TYPE_MAXIMUM, TIME_T_MIN, TIME_T_MAX, TIME_T_MIDPOINT)
(time_t_avg, time_t_add_ok): Remove.
(mktime_min, mktime_max): New constants.
(leapyear, isdst_differ): Use bool for booleans.
(ydhms_diff, guess_time_tm, ranged_convert, __mktime_internal):
Use long_int, not time_t, for mktime differences.
(long_int_avg): New function, replacing time_t_avg.
INT_ADD_WRAPV replaces time_t_add_ok.
(guess_time_tm): 6th arg is now long_int, not time_t const *.
All uses changed.
(convert_time): New function.
(ranged_convert): Use it.
(__mktime_internal): Last arg now points to mktime_offset_t, not
time_t. All uses changed. This is a no-op on glibc, where
mktime_offset_t is always time_t. Use int, not time_t, for UTC
offset guess. Directly check for integer overflow instead of
using a heuristic that works only 99.9...% of the time.
Access *OFFSET only once, to avoid an unlikely race if the
compiler delays a load and if this cascades into a signed integer
overflow.
(mktime): Move tzsettish code to my_tzset, and move
localtime_offset to within mktime so that it doesn’t
need a separate ifdef.
(main) [DEBUG_MKTIME]: Speed up by using localtime_r
instead of localtime.
* time/timegm.c: Copy from Gnulib. This has the following changes:
Include mktime-internal.h.
[!_LIBC]: Include config.h and time.h. Do not include
timegm.h or time_r.h. Make __mktime_internal a macro,
and include mktime-internal.h to get its declaration.
(timegm): Temporary is now mktime_offset_t, not time_t.
This affects only Gnulib.
