On Mon, Nov 27, 2017 at 5:58 PM, Jeff Law <l...@redhat.com> wrote: > On 11/27/2017 02:22 AM, Dominik Inführ wrote: >> Thanks for all the reviews! I’ve revised the patch, the operator_delete_flag >> is now stored in tree_decl_with_vis (there already seem to be some >> FUNCTION_DECL-flags in there). I’ve also added the option -fallocation-dce >> to disable this optimization. It bootstraps and no regressions on aarch64 >> and x86_64. >> >> The problem with this patch is what Marc noticed: it omits too many >> allocations. The C++ standard seems to only allow to omit "replaceable >> global allocation functions (18.6.1.1, 18.6.1.2)”. So e.g. no class-specific >> or user-defined allocations. I am not sure what’s the best way to implement >> this. Just checking the function declarations might not be enough and seems >> more like a hack. The better way seems to introduce a __builtin_operator_new >> like Marc mentioned. In which way would you implement this? Could you please >> give me some pointers here to look at? > Just a nit. Make sure to mention BZ 23383 in your ChangeLog entry. > Like this: > > c++/23383 > * tree-core.h (blah blah): What changed. > > > Jakub and Richi probably have a better understanding of the builtin > mechanisms than I do. I'll leave it for them to comment on how best to > proceed there.
I don't see why a builtin is necessary, can the FE not see which one is the global allocation function? Anyways, there are no FE specific builtins, traditionally FEs have used special keywords - you might want to search for RID_BUILTIN_LAUNDER for example. Richard. > jeff
