aaron.ballman added a comment. In D125919#3554233 <https://reviews.llvm.org/D125919#3554233>, @rjmccall wrote:
> In D125919#3554195 <https://reviews.llvm.org/D125919#3554195>, @aaron.ballman > wrote: > >> However, I reverted the changes in this patch in >> c745f2ce6c03bc6d1e59cac69cc15923d4400191 >> <https://reviews.llvm.org/rGc745f2ce6c03bc6d1e59cac69cc15923d4400191> as I >> don't think they're correct. I've got some open questions on the WG14 >> reflectors regarding this function type rewriting exercise, but I think my >> dropping of the `_Atomic` qualifier is likely wrong in this patch and the >> fact that we're losing source fidelity in the AST is definitely an issue. >> The subject of https://github.com/llvm/llvm-project/issues/39595 was the >> behavior of the `_Atomic` specifier in a `_Generic` selection; when I >> realized we don't fully implement DR423, I mistakenly connected the issue >> with the DR. But now that I no longer think the `_Atomic` qualifier should >> be dropped as I was doing, these changes really don't address the issue in >> `_Generic`. > > The source fidelity issue seems like it could be solved with `AdjustedType`. > What's the issue with `_Generic`? We get this wrong: _Atomic int f(void); int main(void) { _Generic(f(), int: 0); // Error, no matching association } The controlling expression has to undergo lvalue conversion, which drops the `_Atomic` qualifier per C2x 6.3.2.1p2, so we should match the only association rather than error. We do perform the lvalue conversion: https://github.com/llvm/llvm-project/blob/main/clang/lib/Sema/SemaExpr.cpp#L1650 but for whatever reason, we're not matching its type to the association type. Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D125919/new/ https://reviews.llvm.org/D125919 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
