hubert.reinterpretcast added inline comments. ================ Comment at: lib/Sema/SemaExpr.cpp:1169 @@ +1168,3 @@ + if (LHSElemType == S.Context.Float128Ty && + RHSElemType == S.Context.LongDoubleTy) + return true; ---------------- nemanjai wrote: > hubert.reinterpretcast wrote: > > I do not believe that the width of `long double` is sufficiently > > established to be the same as that of `__float128` in this context. > This would certainly cause any attempts to convert between some different > implementation of **`long double` **(i.e. the Intel 80-bit type). I believe > that this behaviour is desired in all cases where **`long double`** and > **`double`** have a different representation. Namely, we do not currently > have any support for converting between **`fp128`** and anything that has > precision >= **`double`** that is not actually **`double`**. > > What I propose to do here and in other locations where we diagnose > conversions between the two types is that the check is: > - One type is `__float128` > - The other is `long double` > - The representation of `long double` is not `llvm::APFloat::IEEEdouble` > > Basically in this function, the early exit path would be: > - representations are the same or > - representation of `long double` is `llvm::APFloat::IEEEdouble` This really sounds like a property of the target. The situation described in D15120#inline-141210 is similar.
I would not want to do a virtual function call without early exits here. So, perhaps the `TargetInfo` should be queried only at the point where we would otherwise return `true`. I can't say that I like the name of this function now. Perhaps `unsupportedTypeConversion`? Repository: rL LLVM http://reviews.llvm.org/D15120 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
