[clang] 96295a1 - [Clang] Fix a crash when forming a type from an indexed TTP. (#222326)

[via cfe-commits]

Author: Corentin Jabot
Date: 2026-09-10T09:36:09+02:00
New Revision: 96295a1412f9afbee9d4a3c2701e83f5a529a9cc

URL: https://github.com/llvm/llvm-project/commit/96295a1412f9afbee9d4a3c2701e83f5a529a9cc
DIFF: https://github.com/llvm/llvm-project/commit/96295a1412f9afbee9d4a3c2701e83f5a529a9cc.diff

LOG: [Clang] Fix a crash when forming a type from an indexed TTP. (#222326)

Unreported 24 issue so no release note.

Added: 
    

Modified: 
    clang/lib/Parse/ParseExpr.cpp
    clang/test/SemaCXX/cxx2d-pack-indexing-template.cpp

Removed: 
    


################################################################################
diff  --git a/clang/lib/Parse/ParseExpr.cpp b/clang/lib/Parse/ParseExpr.cpp
index fd6b290d9b673..ef89b77d0a997 100644
--- a/clang/lib/Parse/ParseExpr.cpp
+++ b/clang/lib/Parse/ParseExpr.cpp
@@ -905,7 +905,7 @@ Parser::ParseCastExpression(CastParseKind ParseKind, bool isAddressOfOperand,
         if (TryAnnotateTypeOrScopeToken())
           return ExprError();
         if (Tok.isOneOf(tok::annot_cxxscope, tok::annot_pack_indexing_type,
-                        tok::annot_template_id))
+                        tok::annot_template_id, tok::annot_typename))
           return ParseCastExpression(ParseKind, isAddressOfOperand,
                                      CorrectionBehavior, isVectorLiteral,
                                      NotPrimaryExpression);

diff  --git a/clang/test/SemaCXX/cxx2d-pack-indexing-template.cpp b/clang/test/SemaCXX/cxx2d-pack-indexing-template.cpp
index 0298be66b1a86..f1d9b1b8ce3d0 100644
--- a/clang/test/SemaCXX/cxx2d-pack-indexing-template.cpp
+++ b/clang/test/SemaCXX/cxx2d-pack-indexing-template.cpp
@@ -105,6 +105,18 @@ auto ctad() {
   return x;
 }
 static_assert(__is_same(decltype(ctad<Deduce>()), Deduce<int>));
+
+template <template <class> class... TT>
+auto ctad_paren() {
+  return TT...[0](42);
+}
+static_assert(__is_same(decltype(ctad_paren<Deduce>()), Deduce<int>));
+
+template <template <class> class... TT>
+auto ctad_braced() {
+  return TT...[1]{42};
+}
+static_assert(__is_same(decltype(ctad_braced<A, Deduce>()), Deduce<int>));
 }
 
 namespace deduction_guides {