Require the object type of a member access expression ("." or "->") to

be complete.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@89042 91177308-0d34-0410-b5e6-96231b3b80d8

5 files changed, 31 insertions, 9 deletions

diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td
index e1fe4dd4b6..fd544827b1 100644
--- a/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/include/clang/Basic/DiagnosticSemaKinds.td
@@ -401,7 +401,9 @@ def note_ambig_member_ref_scope : Note<
   "lookup from the current scope refers here">;
 def err_qualified_member_nonclass : Error<
   "qualified member access refers to a member in %0">;
-
+def err_incomplete_member_access : Error<
+  "member access into incomplete type %0">;
+  
 // C++ class members
 def err_storageclass_invalid_for_member : Error<
   "storage class specified for a member declaration">;
diff --git a/lib/Sema/SemaExprCXX.cpp b/lib/Sema/SemaExprCXX.cpp
index fdce0e6c2d..dd3fd2c5c1 100644
--- a/lib/Sema/SemaExprCXX.cpp
+++ b/lib/Sema/SemaExprCXX.cpp
@@ -2141,12 +2141,19 @@ Sema::ActOnStartCXXMemberReference(Scope *S, ExprArg Base, SourceLocation OpLoc,
     return move(Base);
   }
 
+  // The object type must be complete (or dependent).
+  if (!BaseType->isDependentType() &&
+      RequireCompleteType(OpLoc, BaseType, 
+                          PDiag(diag::err_incomplete_member_access)))
+    return ExprError();
+  
   // C++ [basic.lookup.classref]p2:
   //   If the id-expression in a class member access (5.2.5) is an
-  //   unqualified-id, and the type of the object expres- sion is of a class
+  //   unqualified-id, and the type of the object expression is of a class
   //   type C (or of pointer to a class type C), the unqualified-id is looked
   //   up in the scope of class C. [...]
   ObjectType = BaseType.getAsOpaquePtr();
+  
   return move(Base);
 }
 
diff --git a/lib/Sema/SemaTemplate.cpp b/lib/Sema/SemaTemplate.cpp
index 317d133954..a799ddb24b 100644
--- a/lib/Sema/SemaTemplate.cpp
+++ b/lib/Sema/SemaTemplate.cpp
@@ -130,12 +130,17 @@ TemplateNameKind Sema::isTemplateName(Scope *S,
     QualType ObjectType = QualType::getFromOpaquePtr(ObjectTypePtr);
     LookupCtx = computeDeclContext(ObjectType);
     isDependent = ObjectType->isDependentType();
+    assert((isDependent || !ObjectType->isIncompleteType()) && 
+           "Caller should have completed object type");
   } else if (SS.isSet()) {
     // This nested-name-specifier occurs after another nested-name-specifier,
     // so long into the context associated with the prior nested-name-specifier.
-
     LookupCtx = computeDeclContext(SS, EnteringContext);
     isDependent = isDependentScopeSpecifier(SS);
+    
+    // The declaration context must be complete.
+    if (LookupCtx && RequireCompleteDeclContext(SS))
+      return TNK_Non_template;
   }
 
   LookupResult Found(*this, TName, SourceLocation(), LookupOrdinaryName);
@@ -145,11 +150,6 @@ TemplateNameKind Sema::isTemplateName(Scope *S,
     // computed, which is either the type of the base of a member access
     // expression or the declaration context associated with a prior
     // nested-name-specifier.
-
-    // The declaration context must be complete.
-    if (!LookupCtx->isDependentContext() && RequireCompleteDeclContext(SS))
-      return TNK_Non_template;
-
     LookupQualifiedName(Found, LookupCtx);
 
     if (ObjectTypePtr && Found.empty()) {
diff --git a/test/SemaTemplate/class-template-spec.cpp b/test/SemaTemplate/class-template-spec.cpp
index 5bc9a6cd67..2808404b1d 100644
--- a/test/SemaTemplate/class-template-spec.cpp
+++ b/test/SemaTemplate/class-template-spec.cpp
@@ -19,7 +19,7 @@ int test_specs(A<float, float> *a1, A<float, int> *a2) {
 int test_incomplete_specs(A<double, double> *a1, 
                           A<double> *a2)
 {
-  (void)a1->x; // expected-error{{incomplete definition of type 'A<double, double>'}}
+  (void)a1->x; // expected-error{{member access into incomplete type}}
   (void)a2->x; // expected-error{{implicit instantiation of undefined template 'struct A<double, int>'}}
 }
 
diff --git a/test/SemaTemplate/member-function-template.cpp b/test/SemaTemplate/member-function-template.cpp
index 756b510e97..1d46d31e35 100644
--- a/test/SemaTemplate/member-function-template.cpp
+++ b/test/SemaTemplate/member-function-template.cpp
@@ -60,3 +60,16 @@ struct Functor {
 void test_Functor(Functor f) {
   f(1);
 }
+
+// Instantiation on ->
+template<typename T>
+struct X1 {
+  template<typename U> U& get();
+};
+
+template<typename T> struct X2; // expected-note{{here}}
+
+void test_incomplete_access(X1<int> *x1, X2<int> *x2) {
+  float &fr = x1->get<float>();
+  (void)x2->get<float>(); // expected-error{{implicit instantiation of undefined template}}
+}