From f19de1ce44b9c7ffdeb388d6fe2fa8a1d0288f64 Mon Sep 17 00:00:00 2001
From: John McCall <rjmccall@apple.com>
Date: Wed, 14 Apr 2010 01:27:20 +0000
Subject: [PATCH] Mark a function declaration invalid if any of its parameter
 declarations are invalid.  Prevents a crash-on-invalid during template
 instantiation. I... really don't understand how this wasn't already present.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@101203 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Sema/SemaDecl.cpp                    |  3 +++
 test/SemaTemplate/instantiate-method.cpp | 10 ++++++++++
 2 files changed, 13 insertions(+)

diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index ab61487b68..a2d0e18728 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -3098,6 +3098,9 @@ Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC,
         assert(Param->getDeclContext() != NewFD && "Was set before ?");
         Param->setDeclContext(NewFD);
         Params.push_back(Param);
+
+        if (Param->isInvalidDecl())
+          NewFD->setInvalidDecl();
       }
     }
 
diff --git a/test/SemaTemplate/instantiate-method.cpp b/test/SemaTemplate/instantiate-method.cpp
index 635d839b2b..3ef07d356d 100644
--- a/test/SemaTemplate/instantiate-method.cpp
+++ b/test/SemaTemplate/instantiate-method.cpp
@@ -117,3 +117,13 @@ struct X3 {
 
 
 template struct X3<double>;
+
+// Don't try to instantiate this, it's invalid.
+namespace test1 {
+  template <class T> class A {};
+  template <class T> class B {
+    void foo(A<test1::Undeclared> &a) // expected-error {{no member named 'Undeclared' in namespace 'test1'}}
+    {}
+  };
+  template class B<int>;
+}
-- 
2.40.0