> Il 29/12/2016 13:03, Thiago Macieira ha scritto: > > How is it ia win for std::vector to achieve next year what QVector has done > > for the past 7 or 8? > > Because with std::vector it has been possible for the last 16 years (by > using a custom allocator), _and_ this behaviour has been well-defined by > a Standard (unlike QVector, whose behaviour has always been undocumented > / implementation defined, and possibly changed between Qt 3/4/5 and > maybe will change again in Qt 6).
What is the logic of the C++ standard to introduce a new keyword (alignas) and have default containers ignoring them?... >From my POV, QVector succeeds where the standard std::vector fails. Yes, using a custom allocator is possible. But this another case where Qt succeeds in its philosohphy of easing programming. I just wish the Qt behaviour could be officialy documented. That was my original query, actually. >In C++17 std::vector (well, std::allocator) must honour overly-aligned types: > http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0035r4.html You might be right about that (hopefully), but the quoted document mentions operator new with a new alignment capability, but container allocators are not mentionned (AFAICS) Philippe _______________________________________________ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
