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* [Bug c++/62036] New: Braced-init-list issuing -Wsequence-point warning @ 2014-08-06 14:08 dacamara.cameron at gmail dot com 2014-08-06 15:06 ` [Bug c++/62036] " redi at gcc dot gnu.org ` (2 more replies) 0 siblings, 3 replies; 4+ messages in thread From: dacamara.cameron at gmail dot com @ 2014-08-06 14:08 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=62036 Bug ID: 62036 Summary: Braced-init-list issuing -Wsequence-point warning Product: gcc Version: 4.8.2 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: dacamara.cameron at gmail dot com #include <algorithm> #include <iostream> #include <iterator> #include <thread> int main() { int arr[10]; std::iota(std::begin(arr), std::end(arr), 1); using itr_t = decltype(std::begin(arr)); // the function that will display each element auto f = [] (itr_t first, itr_t last) {while (first != last) std::cout<<*(first++)<<' ';}; // we have 3 threads so we need to figure out the ranges for each thread to show int increment = std::distance(std::begin(arr), std::end(arr)) / 3; auto first = std::begin(arr); auto to = first + increment; auto last = std::end(arr); std::thread threads[3] = { std::thread{f, first, to}, std::thread{f, (first = to), (to += increment)}, std::thread{f, (first = to), last} // go to last here to account for odd array sizes }; for (auto&& t : threads) t.join(); } I'm getting the sequence point warning with this piece of code and when I execute it the thread at threads[1] prints nothing whatsoever. This should be well defined according to the standard (I'm using sec. 8.5.4.4 as reference). The fact that gcc even issues the -Wsequence-point warning is indicative that the standard isn't being followed. ^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug c++/62036] Braced-init-list issuing -Wsequence-point warning 2014-08-06 14:08 [Bug c++/62036] New: Braced-init-list issuing -Wsequence-point warning dacamara.cameron at gmail dot com @ 2014-08-06 15:06 ` redi at gcc dot gnu.org 2014-08-06 15:12 ` dacamara.cameron at gmail dot com 2014-08-06 18:36 ` dacamara.cameron at gmail dot com 2 siblings, 0 replies; 4+ messages in thread From: redi at gcc dot gnu.org @ 2014-08-06 15:06 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=62036 --- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> --- As pointed out at http://stackoverflow.com/questions/25115189/optimization-bug-regarding-gcc-stdthread#comment39095137_25115189 (where you apparently copied this code from) there's a known bug which is fixed in GCC 4.9, see PR51253 ^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug c++/62036] Braced-init-list issuing -Wsequence-point warning 2014-08-06 14:08 [Bug c++/62036] New: Braced-init-list issuing -Wsequence-point warning dacamara.cameron at gmail dot com 2014-08-06 15:06 ` [Bug c++/62036] " redi at gcc dot gnu.org @ 2014-08-06 15:12 ` dacamara.cameron at gmail dot com 2014-08-06 18:36 ` dacamara.cameron at gmail dot com 2 siblings, 0 replies; 4+ messages in thread From: dacamara.cameron at gmail dot com @ 2014-08-06 15:12 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=62036 --- Comment #2 from Cameron <dacamara.cameron at gmail dot com> --- Welp looks like my friend got to it before I did. My bad. Carry on and good work! ^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug c++/62036] Braced-init-list issuing -Wsequence-point warning 2014-08-06 14:08 [Bug c++/62036] New: Braced-init-list issuing -Wsequence-point warning dacamara.cameron at gmail dot com 2014-08-06 15:06 ` [Bug c++/62036] " redi at gcc dot gnu.org 2014-08-06 15:12 ` dacamara.cameron at gmail dot com @ 2014-08-06 18:36 ` dacamara.cameron at gmail dot com 2 siblings, 0 replies; 4+ messages in thread From: dacamara.cameron at gmail dot com @ 2014-08-06 18:36 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=62036 Cameron <dacamara.cameron at gmail dot com> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |RESOLVED Resolution|--- |DUPLICATE --- Comment #3 from Cameron <dacamara.cameron at gmail dot com> --- duplicate of bug 51253 *** This bug has been marked as a duplicate of bug 51253 *** ^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2014-08-06 18:36 UTC | newest] Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2014-08-06 14:08 [Bug c++/62036] New: Braced-init-list issuing -Wsequence-point warning dacamara.cameron at gmail dot com 2014-08-06 15:06 ` [Bug c++/62036] " redi at gcc dot gnu.org 2014-08-06 15:12 ` dacamara.cameron at gmail dot com 2014-08-06 18:36 ` dacamara.cameron at gmail dot com
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