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From: "jengelh at inai dot de" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug libstdc++/113159] New: More robust std::sort for silly comparator functions Date: Wed, 27 Dec 2023 23:04:20 +0000 [thread overview] Message-ID: <bug-113159-4@http.gcc.gnu.org/bugzilla/> (raw) https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113159 Bug ID: 113159 Summary: More robust std::sort for silly comparator functions Product: gcc Version: 14.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: libstdc++ Assignee: unassigned at gcc dot gnu.org Reporter: jengelh at inai dot de Target Milestone: --- Type: enhancement Version: 13.2.1 20231130 [revision 741743c028dc00f27b9c8b1d5211c1f602f2fddd] (SUSE Linux) x86_64 Input: #include <algorithm> #include <cstdlib> #include <vector> int main() { std::vector<int> v(256); sort(v.begin(), v.end(), [](int a, int b) -> bool { return rand() & 1; }); // alternatively, { return true; } // // -D_GLIBCXX_DEBUG can diagnose obviously-broken cases like // {return true;}, but won't necessarily for // rand()&1 at all times. } Observed output: <SIGSEGV> Expected output: Though I recognize this is undefined behavior, I would love to see the implementation not run into an out-of-bounds access. glibc's qsort for example stays within the array bounds even if given a buggy comparator like that.
next reply other threads:[~2023-12-27 23:04 UTC|newest] Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top 2023-12-27 23:04 jengelh at inai dot de [this message] 2023-12-28 1:16 ` [Bug libstdc++/113159] " redi at gcc dot gnu.org 2023-12-28 8:46 ` xry111 at gcc dot gnu.org 2023-12-28 18:34 ` redi at gcc dot gnu.org 2023-12-28 18:42 ` amonakov at gcc dot gnu.org 2023-12-29 0:23 ` jengelh at inai dot de 2023-12-29 0:33 ` pinskia at gcc dot gnu.org 2023-12-29 7:56 ` fw at gcc dot gnu.org 2024-01-03 1:41 ` xry111 at gcc dot gnu.org 2024-01-03 11:09 ` redi at gcc dot gnu.org
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