[Bug libstdc++/113159] More robust std::sort for silly comparator functions
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113159 --- Comment #8 from Jonathan Wakely --- I haven't seen a proof that libstdc++'s std::sort can't be made more robust without losing performance. Maybe cheap range checks can be done conditionally when _GLIBCXX_ASSERTIONS is defined, or maybe they'll be cheap enough to do unconditionally. Some work is needed to see what's feasible, but there's no reason to just close the request as INVALID.
[Bug libstdc++/113159] More robust std::sort for silly comparator functions
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113159 --- Comment #7 from Xi Ruoyao --- Generally I hate the idea to punish innocent programs (making them slower) just to satisfy buggy programs. If it's due to Hyrum's rule then fine, but here Hyrum rule does not apply.
[Bug libstdc++/113159] More robust std::sort for silly comparator functions
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113159 Florian Weimer changed: What|Removed |Added CC||fw at gcc dot gnu.org --- Comment #6 from Florian Weimer --- We'll likely revert most of the qsort changes for glibc 2.39 because the new implementation is both slower and has a significant backwards compatibility impact.
[Bug libstdc++/113159] More robust std::sort for silly comparator functions
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113159 --- Comment #5 from Andrew Pinski --- (In reply to Jan Engelhardt from comment #4) > >And in upcoming Glibc-2.39 there will be a major reimplementation of qsort > > Even so, a recent commit strongly suggests that sticking to array bounds > remains important: So IIRC the reasoning is because of bugs in older (current as of a month ago even) versions of LLVM which crashes on a comparison with itself. Basically broken comparison functions are forcing workarounds really. Note GCC uses its own sort function due which is designed to detect the brokeness of comparison functions even; see PR 109187, PR 90282, PR 87281, PR 84345, etc.
[Bug libstdc++/113159] More robust std::sort for silly comparator functions
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113159 Jan Engelhardt changed: What|Removed |Added CC||fweimer at redhat dot com --- Comment #4 from Jan Engelhardt --- >And in upcoming Glibc-2.39 there will be a major reimplementation of qsort Even so, a recent commit strongly suggests that sticking to array bounds remains important: commit b9390ba93676c4b1e87e218af5e7e4bb596312ac Author: Florian Weimer Date: Mon Dec 4 06:35:56 2023 +0100 stdlib: Fix array bounds protection in insertion sort phase of qsort
[Bug libstdc++/113159] More robust std::sort for silly comparator functions
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113159 Alexander Monakov changed: What|Removed |Added CC||amonakov at gcc dot gnu.org --- Comment #3 from Alexander Monakov --- Can you outline what would merge criteria for such an enhancement look like? If it comes at a cost of increased code complexity and runtime overhead, what sacrifice is acceptable in the name of increased robustness?
[Bug libstdc++/113159] More robust std::sort for silly comparator functions
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113159 Jonathan Wakely changed: What|Removed |Added Last reconfirmed||2023-12-28 Ever confirmed|0 |1 Resolution|INVALID |--- Status|RESOLVED|NEW --- Comment #2 from Jonathan Wakely --- I disagree, it's a perfectly valid wish. But somebody needs to work on it, or nothing will happen and it will just stay open forever.
[Bug libstdc++/113159] More robust std::sort for silly comparator functions
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113159 Xi Ruoyao changed: What|Removed |Added Resolution|--- |INVALID Status|UNCONFIRMED |RESOLVED CC||xry111 at gcc dot gnu.org --- Comment #1 from Xi Ruoyao --- Glibc qsort had been slower than std::sort. And in upcoming Glibc-2.39 there will be a major reimplementation of qsort, now it's unclear if it will still keep the behavior you want. Anyway this shouldn't be something we should rely on. Thus I don't think this is valid.
[Bug libstdc++/113159] More robust std::sort for silly comparator functions
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113159 Jonathan Wakely changed: What|Removed |Added Severity|normal |enhancement
