pengfei added a comment. In D157297#4592851 <https://reviews.llvm.org/D157297#4592851>, @aaron.ballman wrote:
> In D157297#4590886 <https://reviews.llvm.org/D157297#4590886>, @pengfei wrote: > >> BTW, maybe @aaron.ballman knows why we don't support such syntax in C++. > > The return statement expects an expression or braced init list: > http://eel.is/c++draft/stmt.jump#general-1 but we really only need to care > about the expression form (there's no braces in sight). > Grammatically, the leading `::` will parse as a qualified-id because it > matches the production for nested-name-specifier: > http://eel.is/c++draft/expr.prim.id.qual#nt:qualified-id > That needs to be followed by an unqualified-id > (http://eel.is/c++draft/expr.prim.id.unqual#nt:unqualified-id), but the open > paren does not match any of the grammar productions, so this is a syntax > error. Thanks @aaron.ballman for the detailed explanation! I have learnt it. @lygstate maybe include Aaron's explanation in commit message? CHANGES SINCE LAST ACTION https://reviews.llvm.org/D157297/new/ https://reviews.llvm.org/D157297 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
