EricWF added inline comments.
================ Comment at: include/exception:85 +#if defined(_LIBCPP_ABI_MICROSOFT) +#include <vcruntime_exception.h> ---------------- smeenai wrote: > What's the rationale for relying on Microsoft's exception implementation > rather than libc++'s? `vcruntime_new.h` brings in `vcruntime_exception.h` which defines all of the `exception` symbols as inline. We have no choice but to cede to them. ================ Comment at: include/new:96 +#if defined(_LIBCPP_ABI_MICROSOFT) +#include <new.h> +#endif ---------------- smeenai wrote: > `new.h` will pull in `new` unless you define certain macros. Is that > desirable? That's not how I read the `new.h` header. In MSVC 2015 `new.h` pulls in `vcruntime_new.h` but it also declares `std::new_handler` and `std::set_new_handler`. `<new>` actually avoid declaring certain things if `new.h` has already been included. `std::get_new_handler` is the only function declared in `<new>` that is not declared in `<new.h>`, however using this function also requires linking to the MSVC C++ STL which we can't do. It's not a great situation to be in, but I don't see how to avoid it. ================ Comment at: include/new:138 +typedef void (*new_handler)(); +_LIBCPP_FUNC_VIS new_handler set_new_handler(new_handler) _NOEXCEPT; ---------------- smeenai wrote: > Again, why defer these to Microsoft's STL? In particular, `set_new_handler` > and `get_new_handler` seem to be part of `msvcprt`, which means we would take > a runtime dependency on Microsoft's C++ library, which doesn't seem great. > > These functions should map pretty well to `_query_new_handler` and > `_set_new_handler` (apart from the different function pointer signature, > which can be thunked around), right? We have to assume these declarations/definitions have already been included via a user including `new.h`, so we can't redefine them. `std::set_new_handler` seem to actually be a part of the CRT startup files, so we can't avoid using it (AFAIK). > These functions should map pretty well to _query_new_handler and > _set_new_handler Those functions take/return entirely different function types. So IDK how to turn the function pointer returned from `_query_new_handler` into an entirely different function type and return it from `get_new_handler`, at least not in a meaningful way. ================ Comment at: include/new:177 +#if !defined(_LIBCPP_ABI_MICROSOFT) + ---------------- smeenai wrote: > Might be helpful to have a comment explaining why we wanna defer these to > msvcrt on Windows? > > Also, VS 2015 doesn't seem to have the sized and aligned allocation and > deallocation functions. I haven't checked 2017. You're right that `VS 2015` doesn't have aligned `new/delete`. However until we can correctly implement `get_new_handler` we won't be able to correctly implement the additional aligned `new/delete` overloads. https://reviews.llvm.org/D28785 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
