[Clang][C++26] Implement Pack Indexing (P2662R3). (#72644)

Implements https://isocpp.org/files/papers/P2662R3.pdf

The feature is exposed as an extension in older language modes.
Mangling is not yet supported and that is something we will have to do before release.

1 files changed, 10 insertions, 0 deletions

diff --git a/clang/lib/AST/ASTStructuralEquivalence.cpp b/clang/lib/AST/ASTStructuralEquivalence.cpp
index be7a850a..a7ddf6d 100644
--- a/clang/lib/AST/ASTStructuralEquivalence.cpp
+++ b/clang/lib/AST/ASTStructuralEquivalence.cpp
@@ -1292,6 +1292,16 @@ static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
       return false;
     break;
 
+  case Type::PackIndexing:
+    if (!IsStructurallyEquivalent(Context,
+                                  cast<PackIndexingType>(T1)->getPattern(),
+                                  cast<PackIndexingType>(T2)->getPattern()))
+      if (!IsStructurallyEquivalent(Context,
+                                    cast<PackIndexingType>(T1)->getIndexExpr(),
+                                    cast<PackIndexingType>(T2)->getIndexExpr()))
+        return false;
+    break;
+
   case Type::ObjCInterface: {
     const auto *Iface1 = cast<ObjCInterfaceType>(T1);
     const auto *Iface2 = cast<ObjCInterfaceType>(T2);