From f35cbc2c3e82656bbbd8a433cbcf47aa623721b3 Mon Sep 17 00:00:00 2001
From: Dan Katz <katzdm@gmail.com>
Date: Wed, 12 Feb 2025 15:55:43 -0500
Subject: [PATCH] Fix segfault.

---
 clang/lib/AST/ExprConstantMeta.cpp | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/clang/lib/AST/ExprConstantMeta.cpp b/clang/lib/AST/ExprConstantMeta.cpp
index 7133162ac1ed..225d8a7bdc79 100644
--- a/clang/lib/AST/ExprConstantMeta.cpp
+++ b/clang/lib/AST/ExprConstantMeta.cpp
@@ -2789,6 +2789,10 @@ bool substitute(APValue &Result, ASTContext &C, MetaActions &Meta,
   if (!Meta.CheckTemplateArgumentList(TDecl, ExpandedTArgs, false,
                                       Args[0]->getExprLoc()))
     return true;
+  for (const auto &TArg : ExpandedTArgs)
+    if (TArg.getKind() == TemplateArgument::Expression &&
+        TArg.getAsExpr()->containsErrors())
+      return true;
 
   if (auto *CTD = dyn_cast<ClassTemplateDecl>(TDecl)) {
     void *InsertPos;