r244515 - If a variable template is inside a context with template arguments that is being instantiated, and that instantiation fails, fail our instantiation instead of crashing. Errors have already been emitted.

[Nick Lewycky via cfe-commits]

Author: nicholas
Date: Mon Aug 10 16:54:08 2015
New Revision: 244515

URL: http://llvm.org/viewvc/llvm-project?rev=244515&view=rev
Log:
If a variable template is inside a context with template arguments that is being instantiated, and that instantiation fails, fail our instantiation instead of crashing. Errors have already been emitted.

Modified:
    cfe/trunk/lib/Sema/SemaTemplateInstantiateDecl.cpp
    cfe/trunk/test/SemaCXX/cxx1y-variable-templates_in_class.cpp

Modified: cfe/trunk/lib/Sema/SemaTemplateInstantiateDecl.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaTemplateInstantiateDecl.cpp?rev=244515&r1=244514&r2=244515&view=diff
==============================================================================
--- cfe/trunk/lib/Sema/SemaTemplateInstantiateDecl.cpp (original)
+++ cfe/trunk/lib/Sema/SemaTemplateInstantiateDecl.cpp Mon Aug 10 16:54:08 2015
@@ -1143,6 +1143,7 @@ Decl *TemplateDeclInstantiator::VisitVar
   VarDecl *VarInst =
       cast_or_null<VarDecl>(VisitVarDecl(Pattern,
                                          /*InstantiatingVarTemplate=*/true));
+  if (!VarInst) return nullptr;
 
   DeclContext *DC = Owner;
 

Modified: cfe/trunk/test/SemaCXX/cxx1y-variable-templates_in_class.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/cxx1y-variable-templates_in_class.cpp?rev=244515&r1=244514&r2=244515&view=diff
==============================================================================
--- cfe/trunk/test/SemaCXX/cxx1y-variable-templates_in_class.cpp (original)
+++ cfe/trunk/test/SemaCXX/cxx1y-variable-templates_in_class.cpp Mon Aug 10 16:54:08 2015
@@ -327,3 +327,14 @@ struct S {
   static int f : I; // expected-error {{static member 'f' cannot be a bit-field}}
 };
 }
+
+namespace b20896909 {
+  // This used to crash.
+  template<typename T> struct helper {};
+  template<typename T> class A {
+    template <typename> static helper<typename T::error> x;  // expected-error {{type 'int' cannot be used prior to '::' because it has no members}}
+  };
+  void test() {
+    A<int> ai;  // expected-note {{in instantiation of}}
+  }
+}