[clang] 44c3a63 - PR45063: Fix crash on invalid processing an elaborated class template-id

[Richard Smith via cfe-commits]

Author: Richard Smith
Date: 2020-03-13T18:53:49-07:00
New Revision: 44c3a63c74dddeef17e424ec76bd90c8582d8a3c

URL: https://github.com/llvm/llvm-project/commit/44c3a63c74dddeef17e424ec76bd90c8582d8a3c
DIFF: https://github.com/llvm/llvm-project/commit/44c3a63c74dddeef17e424ec76bd90c8582d8a3c.diff

LOG: PR45063: Fix crash on invalid processing an elaborated class template-id
with an invalid scope specifier.

Added: 
    

Modified: 
    clang/lib/Sema/SemaTemplate.cpp
    clang/test/Parser/cxx-template-decl.cpp

Removed: 
    


################################################################################
diff  --git a/clang/lib/Sema/SemaTemplate.cpp b/clang/lib/Sema/SemaTemplate.cpp
index f7568e3b62b7..4923d0a6dad2 100755
--- a/clang/lib/Sema/SemaTemplate.cpp
+++ b/clang/lib/Sema/SemaTemplate.cpp
@@ -3814,6 +3814,9 @@ TypeResult Sema::ActOnTagTemplateIdType(TagUseKind TUK,
                                         SourceLocation LAngleLoc,
                                         ASTTemplateArgsPtr TemplateArgsIn,
                                         SourceLocation RAngleLoc) {
+  if (SS.isInvalid())
+    return TypeResult(true);
+
   TemplateName Template = TemplateD.get();
 
   // Translate the parser's template argument list in our AST format.

diff  --git a/clang/test/Parser/cxx-template-decl.cpp b/clang/test/Parser/cxx-template-decl.cpp
index cb8a93fdecb1..3d7a3dc14f4c 100644
--- a/clang/test/Parser/cxx-template-decl.cpp
+++ b/clang/test/Parser/cxx-template-decl.cpp
@@ -269,3 +269,7 @@ namespace AnnotateAfterInvalidTemplateId {
 
   void f() { A<0, 0>::f(); } // expected-error {{ambiguous partial specializations}}
 }
+
+namespace PR45063 {
+  template<class=class a::template b<>> struct X {}; // expected-error {{undeclared identifier 'a'}}
+}