[PATCH 2/3] libstdc++: Optimize __uninitialized_default using memset

Hi, not sure whether I've missed some conditional that would exclude this case, but your change seems to incorrectly handle trivial types that have a non-zero bit pattern of value-initialized object, e.g. pointer to member. Regards, Maciej Cencora

Re: [PATCH 2/3] libstdc++: Optimize __uninitialized_default using memset

han Wakely wrote: > > > > On Thu, 27 Jun 2024 at 13:40, Maciej Cencora wrote: > > > > > > Hi, > > > > > > not sure whether I've missed some conditional that would exclude this > case, but your change seems to incorrectly handle trivial ty

Re: [PATCH 2/3] libstdc++: Optimize __uninitialized_default using memset

I think going the bit_cast way would be the best because it enables the optimization for many more classes including common wrappers like optional, variant, pair, tuple and std::array. Regards, Maciej Cencora czw., 27 cze 2024 o 14:57 Maciej Cencora napisał(a): > You could include some of

Re: [PATCH 2/3] libstdc++: Optimize __uninitialized_default using memset

timized out. I guess the best option would be to introduce in C++ language a new compiler-backed type trait like: std::zero_initialized_object_has_all_zeros_object_representation. Regards, Maciej pt., 28 cze 2024 o 00:25 Jonathan Wakely napisał(a): > On Thu, 27 Jun 2024 at 14:27, Maciej Cen

Re: [WIP RFC] libstdc++: add module std

idden friends. Another thing - P2465r3 mentions only lerp, byte and related ops as special w.r.t skipping export from global namespace in std.compat, but for some reason Microsoft's impl treats 3-arg hypot as special as well. Regards, Maciej Cencora

RE: [PATCH 2/2] libstdc++: Implement for C++26 (P3370R1)

Hi, two issues: 1) #include is missing in std.compat.cc.in 2) does the updated std.compat module actually work? When I experimented with implementing the std module in gcc, I couldn't #include standard headers, after they were imported via std module (since GMF merging isn't implemented yet), i.

RE: [PATCH v2] libstdc++: Implement C++26 features (P2546R5)

Hi, unless I missed it, updates of std and std.compat modules are missing. Regards, Maciej

Re: [PATCH] c++, libstdc++: Implement C++26 P2830R10 - Constexpr Type Ordering

Hi, update of std module is missing. Regards, Maciej

[committed] libstdc++: Fix uses of non-reserved names in headers

Hi, instead of uglyfing all the libstdc++ code wouldn't it be simpler to just ignore all non-reserved macro expansions (+ some special ones like assert) inside system headers on compiler level? Regards, Maciej

Re: [committed] libstdc++: Simplify variant access functions

Hi, variant getter can be implemented in C++17 without using "recursive" calls, but by generating a list of member pointers and applying them with fold expression. Here's an example: https://godbolt.org/z/3vcKjWjPG Regards, Maciej

[PATCH] tree: Fix up tree_code_{length,type}

Hi, you can emulate C++17 inline variables in C++11 with either of the two ways: 1) via a template helper template struct Helper { static constexpr unsigned value[4] = {1, 2, 3, 4}; }; template constexpr unsigned Helper::value[4]; static constexpr auto& arr = Helper<>::value; 2) extern c