EricWF added inline comments.
================ Comment at: lib/CodeGen/CGExprAgg.cpp:1002 + return EmitFinalDestCopy( + E->getType(), CGF.MakeNaturalAlignAddrLValue(Select, E->getType())); +} ---------------- EricWF wrote: > rjmccall wrote: > > Is there something in Sema actually validating that the comparison types is > > trivially copyable? Because EmitFinalDestCopy does not work on non-trivial > > types. > > > > Also, are we certain that we're allowed to do a copy from an actual global > > variable here instead of potentially a constexpr evaluation of the variable > > reference? And if we are doing a copy, are we registering ODR-uses of all > > the variables in Sema? > > > > I don't think you should worry about trying to generate a select between > > the "actual" comparison result values. At least not yet. > There is nothing is Sema validating that these comparison types are trivially > copyable, and according to the standard they don't need to be. > I assumed we only ended up in `CGExprAgg` if the types were trivially > copyable. But I'll look into implementing this for non-trivially copyable > comparison types (although we'll probably never actually encounter them). > > > Also, are we certain that we're allowed to do a copy from an actual global > > variable here instead of potentially a constexpr evaluation of the variable > > reference? > > I'm not sure exactly what this means. How would I observe the difference? > > >And if we are doing a copy, are we registering ODR-uses of all the variables > >in Sema? > > Probably not. I'll double check that. > > > I don't think you should worry about trying to generate a select between > > the "actual" comparison result values. At least not yet. > > I'm not sure exactly what you mean by this. To follow up: >> And if we are doing a copy, are we registering ODR-uses of all the variables >> in Sema? > > Probably not. I'll double check that. We do mark the potential result variables as ODR-used when we first check them when building builtin and defaulted comparison operators. >> I don't think you should worry about trying to generate a select between the >> "actual" comparison result values. At least not yet. > > I'm not sure exactly what you mean by this. Sorry, I see what you mean. You're talking about the comment. Richard asked me to leave that TODO there. https://reviews.llvm.org/D45476 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
