[PATCH] D126907: Deferred Concept Instantiation Implementation Take 2

[Matheus Izvekov via Phabricator via cfe-commits]

mizvekov added inline comments.


================
Comment at: clang/lib/Sema/SemaConcept.cpp:513-534
+  llvm::Optional<MultiLevelTemplateArgumentList> MLTAL =
+      SetupConstraintCheckingTemplateArgumentsAndScope(
+          const_cast<FunctionDecl *>(FD), {}, Scope);
+
   Qualifiers ThisQuals;
   CXXRecordDecl *Record = nullptr;
   if (auto *Method = dyn_cast<CXXMethodDecl>(FD)) {
----------------
mizvekov wrote:
> Unchecked access to MLTAL (Optional).
> 
> Following reduction reproduces a crash here: `-cc1 -std=c++20 -fsyntax-only -ferror-limit 19`.
> ```
> template a b < ;
> template c e ag < ;
> ah) ;
> am = ;
> template <class... ap> class aq {
>   aq(ap...; __attribute__) auto aj() requires(am)
> }
> f() {                  [;                  aq d;                  d.aj
> ```
By the way, disregard that repro, it needs another patch that is not in master.

The unchecked access still does look suspicious though.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D126907/new/

https://reviews.llvm.org/D126907