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Comparing libev/Changes (file contents):
Revision 1.176 by root, Mon Mar 29 12:40:57 2010 UTC vs.
Revision 1.368 by root, Thu Jul 30 00:59:36 2020 UTC

1Revision history for libev, a high-performance and full-featured event loop. 1Revision history for libev, a high-performance and full-featured event loop.
2 2
3TODO: ABI??? API????? Changes??? 3TODO: for next ABI/API change, consider moving EV__IOFDSSET into io->fd instead and provide a getter.
4TODO: win32 write() to socket for signal handling 4TODO: document EV_TSTAMP_T
5TODO: poll asert 5
6 - due to a logic bug, timerfd availability did not always translate
7 into fewer wakeups - libev is now more aggressive in using
8 longer sleeps, even when timerfd is not in use.
9
104.33 Wed Mar 18 13:22:29 CET 2020
11 - no changes w.r.t. 4.32.
12
134.32 (EV only)
14 - the 4.31 timerfd code wrongly changed the priority of the signal
15 fd watcher, which is usually harmless unless signal fds are
16 also used (found via cpan tester service).
17 - the documentation wrongly claimed that user may modify fd and events
18 members in io watchers when the watcher was stopped
19 (found by b_jonas).
20 - new ev_io_modify mutator which changes only the events member,
21 which can be faster. also added ev::io::set (int events) method
22 to ev++.h.
23 - officially allow a zero events mask for io watchers. this should
24 work with older libev versions as well but was not officially
25 allowed before.
26 - do not wake up every minute when timerfd is used to detect timejumps.
27 - do not wake up every minute when periodics are disabled and we have
28 a monotonic clock.
29 - support a lot more "uncommon" compile time configurations,
30 such as ev_embed enabled but ev_timer disabled.
31 - use a start/stop wrapper class to reduce code duplication in
32 ev++.h and make it needlessly more c++-y.
33 - the linux aio backend is no longer compiled in by default.
34 - update to libecb version 0x00010008.
35
364.31 Fri Dec 20 21:58:29 CET 2019
37 - handle backends with minimum wait time a bit better by not
38 waiting in the presence of already-expired timers
39 (behaviour reported by Felipe Gasper).
40 - new feature: use timerfd to detect timejumps quickly,
41 can be disabled with the new EVFLAG_NOTIMERFD loop flag.
42 - document EV_USE_SIGNALFD feature macro.
43
444.30 (EV only)
45 - change non-autoconf test for __kernel_rwf_t by testing
46 LINUX_VERSION_CODE, the most direct test I could find.
47 - fix a bug in the io_uring backend that polled the wrong
48 backend fd, causing it to not work in many cases.
49
504.29 (EV only)
51 - add io uring autoconf and non-autoconf detection.
52 - disable io_uring when some header files are too old.
53
544.28 (EV only)
55 - linuxaio backend resulted in random memory corruption
56 when loop is forked.
57 - linuxaio backend might have tried to cancel an iocb
58 multiple times (was unable to trigger this).
59 - linuxaio backend now employs a generation counter to
60 avoid handling spurious events from cancelled requests.
61 - io_cancel can return EINTR, deal with it. also, assume
62 io_submit also returns EINTR.
63 - fix some other minor bugs in linuxaio backend.
64 - ev_tstamp type can now be overriden by defining EV_TSTAMP_T.
65 - cleanup: replace expect_true/false and noinline by their
66 libecb counterparts.
67 - move syscall infrastructure from ev_linuxaio.c to ev.c.
68 - prepare io_uring integration.
69 - tweak ev_floor.
70 - epoll, poll, win32 Sleep and other places that use millisecond
71 reslution now all try to round up times.
72 - solaris port backend didn't compile.
73 - abstract time constants into their macros, for more flexibility.
74
754.27 Thu Jun 27 22:43:44 CEST 2019
76 - linux aio backend almost completely rewritten to work around its
77 limitations.
78 - linux aio backend now requires linux 4.19+.
79 - epoll backend now mandatory for linux aio backend.
80 - fail assertions more aggressively on invalid fd's detected
81 in the event loop, do not just silently fd_kill in case of
82 user error.
83 - ev_io_start/ev_io_stop now verify the watcher fd using
84 a syscall when EV_VERIFY is 2 or higher.
85
864.26 (EV only)
87 - update to libecb 0x00010006.
88 - new experimental linux aio backend (linux 4.18+).
89 - removed redundant 0-ptr check in ev_once.
90 - updated/extended ev_set_allocator documentation.
91 - replaced EMPTY2 macro by array_needsize_noinit.
92 - minor code cleanups.
93 - epoll backend now uses epoll_create1 also after fork.
94
954.25 Fri Dec 21 07:49:20 CET 2018
96 - INCOMPATIBLE CHANGE: EV_THROW was renamed to EV_NOEXCEPT
97 (EV_THROW still provided) and now uses noexcept on C++11 or newer.
98 - move the darwin select workaround higher in ev.c, as newer versions of
99 darwin managed to break their broken select even more.
100 - ANDROID => __ANDROID__ (reported by enh@google.com).
101 - disable epoll_create1 on android because it has broken header files
102 and google is unwilling to fix them (reported by enh@google.com).
103 - avoid a minor compilation warning on win32.
104 - c++: remove deprecated dynamic throw() specifications.
105 - c++: improve the (unsupported) bad_loop exception class.
106 - backport perl ev_periodic example to C, untested.
107 - update libecb, biggets change is to include a memory fence
108 in ECB_MEMORY_FENCE_RELEASE on x86/amd64.
109 - minor autoconf/automake modernisation.
110
1114.24 Wed Dec 28 05:19:55 CET 2016
112 - bump version to 4.24, as the release tarball inexplicably
113 didn't have the right version in ev.h, even though the cvs-tagged
114 version did have the right one (reported by Ales Teska).
115
1164.23 Wed Nov 16 18:23:41 CET 2016
117 - move some declarations at the beginning to help certain retarded
118 microsoft compilers, even though their documentation claims
119 otherwise (reported by Ruslan Osmanov).
120
1214.22 Sun Dec 20 22:11:50 CET 2015
122 - when epoll detects unremovable fds in the fd set, rebuild
123 only the epoll descriptor, not the signal pipe, to avoid
124 SIGPIPE in ev_async_send. This doesn't solve it on fork,
125 so document what needs to be done in ev_loop_fork
126 (analyzed by Benjamin Mahler).
127 - remove superfluous sys/timeb.h include on win32
128 (analyzed by Jason Madden).
129 - updated libecb.
130
1314.20 Sat Jun 20 13:01:43 CEST 2015
132 - prefer noexcept over throw () with C++ 11.
133 - update ecb.h due to incompatibilities with c11.
134 - fix a potential aliasing issue when reading and writing
135 watcher callbacks.
136
1374.19 Thu Sep 25 08:18:25 CEST 2014
138 - ev.h wasn't valid C++ anymore, which tripped compilers other than
139 clang, msvc or gcc (analyzed by Raphael 'kena' Poss). Unfortunately,
140 C++ doesn't support typedefs for function pointers fully, so the affected
141 declarations have to spell out the types each time.
142 - when not using autoconf, tighten the check for clock_gettime and related
143 functionality.
144
1454.18 Fri Sep 5 17:55:26 CEST 2014
146 - events on files were not always generated properly with the
147 epoll backend (testcase by Assaf Inbal).
148 - mark event pipe fd as cloexec after a fork (analyzed by Sami Farin).
149 - (ecb) support m68k, m88k and sh (patch by Miod Vallat).
150 - use a reasonable fallback for EV_NSIG instead of erroring out
151 when we can't detect the signal set size.
152 - in the absence of autoconf, do not use the clock syscall
153 on glibc >= 2.17 (avoids the syscall AND -lrt on systems
154 doing clock_gettime in userspace).
155 - ensure extern "C" function pointers are used for externally-visible
156 loop callbacks (not watcher callbacks yet).
157 - (ecb) work around memory barriers and volatile apparently both being
158 broken in visual studio 2008 and later (analysed and patch by Nicolas Noble).
159
1604.15 Fri Mar 1 12:04:50 CET 2013
161 - destroying a non-default loop would stop the global waitpid
162 watcher (Denis Bilenko).
163 - queueing pending watchers of higher priority from a watcher now invokes
164 them in a timely fashion (reported by Denis Bilenko).
165 - add throw() to all libev functions that cannot throw exceptions, for
166 further code size decrease when compiling for C++.
167 - add throw () to callbacks that must not throw exceptions (allocator,
168 syserr, loop acquire/release, periodic reschedule cbs).
169 - fix event_base_loop return code, add event_get_callback, event_base_new,
170 event_base_get_method calls to improve libevent 1.x emulation and add
171 some libevent 2.x functionality (based on a patch by Jeff Davey).
172 - add more memory fences to fix a bug reported by Jeff Davey. Better
173 be overfenced than underprotected.
174 - ev_run now returns a boolean status (true meaning watchers are
175 still active).
176 - ev_once: undef EV_ERROR in ev_kqueue.c, to avoid clashing with
177 libev's EV_ERROR (reported by 191919).
178 - (ecb) add memory fence support for xlC (Darin McBride).
179 - (ecb) add memory fence support for gcc-mips (Anton Kirilov).
180 - (ecb) add memory fence support for gcc-alpha (Christian Weisgerber).
181 - work around some kernels losing file descriptors by leaking
182 the kqueue descriptor in the child.
183 - work around linux inotify not reporting IN_ATTRIB changes for directories
184 in many cases.
185 - include sys/syscall.h instead of plain syscall.h.
186 - check for io watcher loops in ev_verify, check for the most
187 common reported usage bug in ev_io_start.
188 - choose socket vs. WSASocket at compiletime using EV_USE_WSASOCKET.
189 - always use WSASend/WSARecv directly on windows, hoping that this
190 works in all cases (unlike read/write/send/recv...).
191 - try to detect signals around a fork faster (test program by
192 Denis Bilenko).
193 - work around recent glibc versions that leak memory in realloc.
194 - rename ev::embed::set to ev::embed::set_embed to avoid clashing
195 the watcher base set (loop) method.
196 - rewrite the async/signal pipe logic to always keep a valid fd, which
197 simplifies (and hopefully correctifies :) the race checking
198 on fork, at the cost of one extra fd.
199 - add fat, msdos, jffs2, ramfs, ntfs and btrfs to the list of
200 inotify-supporting filesystems.
201 - move orig_CFLAGS assignment to after AC_INIT, as newer autoconf
202 versions ignore it before
203 (https://bugzilla.redhat.com/show_bug.cgi?id=908096).
204 - add some untested android support.
205 - enum expressions must be of type int (reported by Juan Pablo L).
206
2074.11 Sat Feb 4 19:52:39 CET 2012
208 - INCOMPATIBLE CHANGE: ev_timer_again now clears the pending status, as
209 was documented already, but not implemented in the repeating case.
210 - new compiletime symbols: EV_NO_SMP and EV_NO_THREADS.
211 - fix a race where the workaround against the epoll fork bugs
212 caused signals to not be handled anymore.
213 - correct backend_fudge for most backends, and implement a windows
214 specific workaround to avoid looping because we call both
215 select and Sleep, both with different time resolutions.
216 - document range and guarantees of ev_sleep.
217 - document reasonable ranges for periodics interval and offset.
218 - rename backend_fudge to backend_mintime to avoid future confusion :)
219 - change the default periodic reschedule function to hopefully be more
220 exact and correct even in corner cases or in the far future.
221 - do not rely on -lm anymore: use it when available but use our
222 own floor () if it is missing. This should make it easier to embed,
223 as no external libraries are required.
224 - strategically import macros from libecb and mark rarely-used functions
225 as cache-cold (saving almost 2k code size on typical amd64 setups).
226 - add Symbols.ev and Symbols.event files, that were missing.
227 - fix backend_mintime value for epoll (was 1/1024, is 1/1000 now).
228 - fix #3 "be smart about timeouts" to not "deadlock" when
229 timeout == now, also improve the section overall.
230 - avoid "AVOIDING FINISHING BEFORE RETURNING" idiom.
231 - support new EV_API_STATIC mode to make all libev symbols
232 static.
233 - supply default CFLAGS of -g -O3 with gcc when original CFLAGS
234 were empty.
235
2364.04 Wed Feb 16 09:01:51 CET 2011
237 - fix two problems in the native win32 backend, where reuse of fd's
238 with different underlying handles caused handles not to be removed
239 or added to the select set (analyzed and tested by Bert Belder).
240 - do no rely on ceil() in ev_e?poll.c.
241 - backport libev to HP-UX versions before 11 v3.
242 - configure did not detect nanosleep and clock_gettime properly when
243 they are available in the libc (as opposed to -lrt).
244
2454.03 Tue Jan 11 14:37:25 CET 2011
246 - officially support polling files with all backends.
247 - support files, /dev/zero etc. the same way as select in the epoll
248 backend, by generating events on our own.
249 - ports backend: work around solaris bug 6874410 and many related ones
250 (EINTR, maybe more), with no performance loss (note that the solaris
251 bug report is actually wrong, reality is far more bizarre and broken
252 than that).
253 - define EV_READ/EV_WRITE as macros in event.h, as some programs use
254 #ifdef to test for them.
255 - new (experimental) function: ev_feed_signal.
256 - new (to become default) EVFLAG_NOSIGMASK flag.
257 - new EVBACKEND_MASK symbol.
258 - updated COMMON IDIOMS SECTION.
259
2604.01 Fri Nov 5 21:51:29 CET 2010
261 - automake fucked it up, apparently, --add-missing -f is not quite enough
262 to make it update its files, so 4.00 didn't install ev++.h and
263 event.h on make install. grrr.
264 - ev_loop(count|depth) didn't return anything (Robin Haberkorn).
265 - change EV_UNDEF to 0xffffffff to silence some overzealous compilers.
266 - use "(libev) " prefix for all libev error messages now.
267
2684.00 Mon Oct 25 12:32:12 CEST 2010
6 - "PORTING FROM LIBEV 3.X TO 4.X" (in ev.pod) is recommended reading. 269 - "PORTING FROM LIBEV 3.X TO 4.X" (in ev.pod) is recommended reading.
7 - ev_embed_stop did not correctly stop the watcher (very good 270 - ev_embed_stop did not correctly stop the watcher (very good
8 testcase by Vladimir Timofeev). 271 testcase by Vladimir Timofeev).
272 - ev_run will now always update the current loop time - it erroneously
273 didn't when idle watchers were active, causing timers not to fire.
274 - fix a bug where a timeout of zero caused the timer not to fire
275 in the libevent emulation (testcase by Péter Szabó).
9 - applied win32 fixes by Michael Lenaghan (also James Mansion). 276 - applied win32 fixes by Michael Lenaghan (also James Mansion).
10 - replace EV_MINIMAL by EV_FEATURES. 277 - replace EV_MINIMAL by EV_FEATURES.
278 - prefer EPOLL_CTL_ADD over EPOLL_CTL_MOD in some more cases, as it
279 seems the former is *much* faster than the latter.
280 - linux kernel version detection (for inotify bug workarounds)
281 did not work properly.
282 - reduce the number of spurious wake-ups with the ports backend.
11 - remove dependency on sys/queue.h on freebsd (patch by Vanilla Hsu). 283 - remove dependency on sys/queue.h on freebsd (patch by Vanilla Hsu).
284 - do async init within ev_async_start, not ev_async_set, which avoids
285 an API quirk where the set function must be called in the C++ API
286 even when there is nothing to set.
12 - add (undocumented) EV_ENABLE when adding events with kqueue, 287 - add (undocumented) EV_ENABLE when adding events with kqueue,
13 this might help with OS X, which seems to need it despite documenting 288 this might help with OS X, which seems to need it despite documenting
14 not to need it (helpfully pointed out by Tilghman Lesher). 289 not to need it (helpfully pointed out by Tilghman Lesher).
15 - do not use poll by default on freebsd, it's broken (what isn't 290 - do not use poll by default on freebsd, it's broken (what isn't
16 on freebsd...). 291 on freebsd...).
292 - allow to embed epoll on kernels >= 2.6.32.
17 - configure now prepends -O3, not appends it, so one can still 293 - configure now prepends -O3, not appends it, so one can still
18 override it. 294 override it.
295 - ev.pod: greatly expanded the portability section, added a porting
296 section, a description of watcher states and made lots of minor fixes.
19 - disable poll backend on AIX, the poll header spams the namespace 297 - disable poll backend on AIX, the poll header spams the namespace
20 and it's not worth working around dead platforms (reported 298 and it's not worth working around dead platforms (reported
21 and analyzed by Aivars Kalvans). 299 and analyzed by Aivars Kalvans).
22 - improve header file compatibility of the standalone eventfd code 300 - improve header file compatibility of the standalone eventfd code
23 in an obscure case. 301 in an obscure case.
… …
26 no sscanf dependency). 304 no sscanf dependency).
27 - new EV_CHILD_ENABLE and EV_SIGNAL_ENABLE configurable settings. 305 - new EV_CHILD_ENABLE and EV_SIGNAL_ENABLE configurable settings.
28 - update libev.m4 HAVE_CLOCK_SYSCALL test for newer glibcs. 306 - update libev.m4 HAVE_CLOCK_SYSCALL test for newer glibcs.
29 - add section on accept() problems to the manpage. 307 - add section on accept() problems to the manpage.
30 - rename EV_TIMEOUT to EV_TIMER. 308 - rename EV_TIMEOUT to EV_TIMER.
31 - rename ev_loop_count/depth/verify. 309 - rename ev_loop_count/depth/verify/loop/unloop.
310 - remove ev_default_destroy and ev_default_fork.
32 - switch to two-digit minor version. 311 - switch to two-digit minor version.
312 - work around an apparent gentoo compiler bug.
313 - define _DARWIN_UNLIMITED_SELECT. just so.
314 - use enum instead of #define for most constants.
315 - improve compatibility to older C++ compilers.
316 - (experimental) ev_run/ev_default_loop/ev_break/ev_loop_new have now
317 default arguments when compiled as C++.
318 - enable automake dependency tracking.
319 - ev_loop_new no longer leaks memory when loop creation failed.
320 - new ev_cleanup watcher type.
33 321
343.9 Thu Dec 31 07:59:59 CET 2009 3223.9 Thu Dec 31 07:59:59 CET 2009
35 - signalfd is no longer used by default and has to be requested 323 - signalfd is no longer used by default and has to be requested
36 explicitly - this means that easy to catch bugs become hard to 324 explicitly - this means that easy to catch bugs become hard to
37 catch race conditions, but the users have spoken. 325 catch race conditions, but the users have spoken.
38 - point out the unspecified signal mask in the documentation, and 326 - point out the unspecified signal mask in the documentation, and
39 that this is a race condition regardless of EV_SIGNALFD. 327 that this is a race condition regardless of EV_SIGNALFD.
40 - backport inotify code to C89. 328 - backport inotify code to C89.
41 - inotify file descriptors could leak into child processes. 329 - inotify file descriptors could leak into child processes.
42 - ev_stat watchers could keep an errornous extra ref on the loop, 330 - ev_stat watchers could keep an erroneous extra ref on the loop,
43 preventing exit when unregistering all watchers (testcases 331 preventing exit when unregistering all watchers (testcases
44 provided by ry@tinyclouds.org). 332 provided by ry@tinyclouds.org).
45 - implement EV_WIN32_HANDLE_TO_FD and EV_WIN32_CLOSE_FD configuration 333 - implement EV_WIN32_HANDLE_TO_FD and EV_WIN32_CLOSE_FD configuration
46 symbols to make it easier for apps to do their own fd management. 334 symbols to make it easier for apps to do their own fd management.
47 - support EV_IDLE_ENABLE being disabled in ev++.h 335 - support EV_IDLE_ENABLE being disabled in ev++.h
… …
53 - changed minimum glibc requirement from glibc 2.9 to 2.7, for 341 - changed minimum glibc requirement from glibc 2.9 to 2.7, for
54 signalfd. 342 signalfd.
55 - add missing string.h include (Denis F. Latypoff). 343 - add missing string.h include (Denis F. Latypoff).
56 - only replace ev_stat.prev when we detect an actual difference, 344 - only replace ev_stat.prev when we detect an actual difference,
57 so prev is (almost) always different to attr. this might 345 so prev is (almost) always different to attr. this might
58 have caused the probems with 04_stat.t. 346 have caused the problems with 04_stat.t.
59 - add ev::timer->remaining () method to C++ API. 347 - add ev::timer->remaining () method to C++ API.
60 348
613.8 Sun Aug 9 14:30:45 CEST 2009 3493.8 Sun Aug 9 14:30:45 CEST 2009
62 - incompatible change: do not necessarily reset signal handler 350 - incompatible change: do not necessarily reset signal handler
63 to SIG_DFL when a sighandler is stopped. 351 to SIG_DFL when a sighandler is stopped.
64 - ev_default_destroy did not properly free or zero some members, 352 - ev_default_destroy did not properly free or zero some members,
65 potentially causing crashes and memory corruption on repated 353 potentially causing crashes and memory corruption on repeated
66 ev_default_destroy/ev_default_loop calls. 354 ev_default_destroy/ev_default_loop calls.
67 - take advantage of signalfd on GNU/Linux systems. 355 - take advantage of signalfd on GNU/Linux systems.
68 - document that the signal mask might be in an unspecified 356 - document that the signal mask might be in an unspecified
69 state when using libev's signal handling. 357 state when using libev's signal handling.
70 - take advantage of some GNU/Linux calls to set cloexec/nonblock 358 - take advantage of some GNU/Linux calls to set cloexec/nonblock
… …
105 - correctly zero the idx values for arrays, so destroying and 393 - correctly zero the idx values for arrays, so destroying and
106 reinitialising the default loop actually works (patch by 394 reinitialising the default loop actually works (patch by
107 Malek Hadj-Ali). 395 Malek Hadj-Ali).
108 - implement ev_suspend and ev_resume. 396 - implement ev_suspend and ev_resume.
109 - new EV_CUSTOM revents flag for use by applications. 397 - new EV_CUSTOM revents flag for use by applications.
110 - add documentation section about priorites. 398 - add documentation section about priorities.
111 - add a glossary to the dcoumentation. 399 - add a glossary to the documentation.
112 - extend the ev_fork description slightly. 400 - extend the ev_fork description slightly.
113 - optimize a jump out of call_pending. 401 - optimize a jump out of call_pending.
114 402
1153.53 Sun Feb 15 02:38:20 CET 2009 4033.53 Sun Feb 15 02:38:20 CET 2009
116 - fix a bug in event pipe creation on win32 that would cause a 404 - fix a bug in event pipe creation on win32 that would cause a
… …
192 do similar changes for event.c. 480 do similar changes for event.c.
193 481
1943.45 Tue Oct 21 21:59:26 CEST 2008 4823.45 Tue Oct 21 21:59:26 CEST 2008
195 - disable inotify usage on linux <2.6.25, as it is broken 483 - disable inotify usage on linux <2.6.25, as it is broken
196 (reported by Yoann Vandoorselaere). 484 (reported by Yoann Vandoorselaere).
197 - ev_stat errornously would try to add inotify watchers 485 - ev_stat erroneously would try to add inotify watchers
198 even when inotify wasn't available (this should only 486 even when inotify wasn't available (this should only
199 have a performance impact). 487 have a performance impact).
200 - ev_once now passes both timeout and io to the callback if both 488 - ev_once now passes both timeout and io to the callback if both
201 occur concurrently, instead of giving timeouts precedence. 489 occur concurrently, instead of giving timeouts precedence.
202 - disable EV_USE_INOTIFY when sys/inotify.h is too old. 490 - disable EV_USE_INOTIFY when sys/inotify.h is too old.
… …
270 - enable inlining with gcc versions 2 and 3. 558 - enable inlining with gcc versions 2 and 3.
271 - work around broken poll implementations potentially 559 - work around broken poll implementations potentially
272 not clearing revents field in ev_poll (Brandon Black) 560 not clearing revents field in ev_poll (Brandon Black)
273 (no such systems are known at this time). 561 (no such systems are known at this time).
274 - work around a bug in realloc on openbsd and darwin, 562 - work around a bug in realloc on openbsd and darwin,
275 also makes the errornous valgrind complaints 563 also makes the erroneous valgrind complaints
276 go away (noted by various people). 564 go away (noted by various people).
277 - fix ev_async_pending, add c++ wrapper for ev_async 565 - fix ev_async_pending, add c++ wrapper for ev_async
278 (based on patch sent by Johannes Deisenhofer. 566 (based on patch sent by Johannes Deisenhofer).
279 - add sensible set method to ev::embed. 567 - add sensible set method to ev::embed.
280 - made integer constants type int in ev.h. 568 - made integer constants type int in ev.h.
281 569
2823.2 Wed Apr 2 17:11:19 CEST 2008 5703.2 Wed Apr 2 17:11:19 CEST 2008
283 - fix a 64 bit overflow issue in the select backend, 571 - fix a 64 bit overflow issue in the select backend,

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