rjmccall added a comment. In D80925#2066915 <https://reviews.llvm.org/D80925#2066915>, @ABataev wrote:
> In D80925#2066728 <https://reviews.llvm.org/D80925#2066728>, @rjmccall wrote: > > > Narrowly this seems to fix the immediate problem, but I feel like we're in > > trouble if tentative parsing is changing the semantic context in ways that > > persist. In particular, I'm concerned that we could end up tentatively > > parsing an ODR use as part of an expression and then completely discarding > > it, causing Sema to think that there's an ODR use later because it never > > sees an L2R conversion (because the expression is not actually used). > > Probably the most architectural thing would be for tentative expression > > parsing to push a possibly-unevaluated context, and then when we claim an > > expression annotation token we can do the retroactive work necessary to > > make it an expression in the proper context. We already have most of the > > logic to support that because of C99 `sizeof`, which is usually not > > evaluated but can be in the narrow circumstance of a VLA. > > > > If we do decide to solve this more narrowly, then we should audit our use > > of the tentative-parsing queries to make sure that we're pushing contexts > > consistently, and we should leave comments in places like this to make sure > > that maintainers understand the subtleties. > > > So, you suggest to not create annot_primary_expr during tentative parsing and > revert parsing completely, right? Not creating the annotation doesn't help if we're still making Sema calls. Also, I assume we're making the annotation token intentionally, probably to avoid re-doing the lookup. But I do think we could recognize that we're doing this, push an unevaluated context in tentative parsing, and then call `TransformToPotentiallyEvaluated` when we see the token in expression parsing. Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D80925/new/ https://reviews.llvm.org/D80925 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
