rjmccall added a comment. In https://reviews.llvm.org/D27163#607100, @rsmith wrote:
> In https://reviews.llvm.org/D27163#607078, @rsmith wrote: > > > A target-specific default for this, simply because there's a lot of code on > > Darwin that happens to violate this language rule, doesn't make sense to me. > > > ... but rjmccall's explanation of the problem helps. The C compatibility > argument also suggests that this should only apply to trivially-copyable > types, and perhaps only scalar types. I would agree with this. The right rule is probably whether the type is trivially-destructed. > The same issue presumably arises for `-fstrict-enums`, which is again only UB > in C++? (Also, C has rather different and much less useful TBAA rules.) > Perhaps some catch-all "I want defined behavior for things that C defines > even though I'm compiling in C++" flag would make sense here? I don't think we've seen problems from any of these. Also I don't think the TBAA rules are as different as you're suggesting, except that C++ actually tries to provide specific rules for unions (that don't match what users actually want). Repository: rL LLVM https://reviews.llvm.org/D27163 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
