Add more testing for the properties of explicit specialization.

Also, eliminate a redundant diagnostic by marking a variable declared
with incomplete type as an invalid declaration.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@83553 91177308-0d34-0410-b5e6-96231b3b80d8

4 files changed, 136 insertions, 0 deletions

diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index 9163aba9f5..fa6d623ae3 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -3454,6 +3454,8 @@ void Sema::ActOnUninitializedDecl(DeclPtrTy dcl,
             
             FinalizeVarWithDestructor(Var, InitType);
           }
+        } else {
+          Var->setInvalidDecl();
         }
       }
     }
diff --git a/test/CXX/temp/temp.spec/temp.expl.spec/p3.cpp b/test/CXX/temp/temp.spec/temp.expl.spec/p3.cpp
new file mode 100644
index 0000000000..2bd1400fae
--- /dev/null
+++ b/test/CXX/temp/temp.spec/temp.expl.spec/p3.cpp
@@ -0,0 +1,14 @@
+// RUN: clang-cc -fsyntax-only -verify %s
+
+namespace N {
+  template<class T> class X;
+}
+
+// FIXME: this diagnostic is terrible (PR3844).
+template<> class X<int> { /* ... */ };	// expected-error {{unqualified-id}}
+
+namespace N {
+  
+template<> class X<char*> { /* ... */ };	// OK: X is a template
+  
+}
\ No newline at end of file
diff --git a/test/CXX/temp/temp.spec/temp.expl.spec/p4.cpp b/test/CXX/temp/temp.spec/temp.expl.spec/p4.cpp
new file mode 100644
index 0000000000..a09cccd1fd
--- /dev/null
+++ b/test/CXX/temp/temp.spec/temp.expl.spec/p4.cpp
@@ -0,0 +1,59 @@
+// RUN: clang-cc -fsyntax-only -verify %s
+
+struct IntHolder { // expected-note{{here}}
+  IntHolder(int);
+};
+
+template<typename T, typename U>
+struct X { // expected-note{{here}}
+  void f() { 
+    T t; // expected-error{{no matching}}
+  }
+
+  void g() { }
+  
+  struct Inner { 
+    T value; 
+  };
+  
+  static T value;
+};
+
+template<typename T, typename U>
+T X<T, U>::value; // expected-error{{no matching constructor}}
+
+IntHolder &test_X_IntHolderInt(X<IntHolder, int> xih) {
+  xih.g(); // okay
+  xih.f(); // expected-note{{instantiation}}
+  
+  // FIXME: diagnostic here has incorrect reason (PR5154)
+  X<IntHolder, int>::Inner inner; // expected-error{{implicit default}}
+  
+  return X<IntHolder, int>::value; // expected-note{{instantiation}}
+}
+
+// Explicitly specialize the members of X<IntHolder, long> to not cause
+// problems with instantiation.
+template<>
+void X<IntHolder, long>::f() { }
+
+template<>
+struct X<IntHolder, long>::Inner {
+  Inner() : value(17) { }
+  IntHolder value;
+};
+
+template<>
+IntHolder X<IntHolder, long>::value = 17;
+
+IntHolder &test_X_IntHolderInt(X<IntHolder, long> xih) {
+  xih.g(); // okay
+  xih.f(); // okay, uses specialization
+  
+  X<IntHolder, long>::Inner inner; // okay, uses specialization
+  
+  return X<IntHolder, long>::value; // okay, uses specialization
+}
+
+template<>
+X<IntHolder, long>::X() { } // expected-error{{instantiated member}}
diff --git a/test/CXX/temp/temp.spec/temp.expl.spec/p5.cpp b/test/CXX/temp/temp.spec/temp.expl.spec/p5.cpp
new file mode 100644
index 0000000000..58682c786f
--- /dev/null
+++ b/test/CXX/temp/temp.spec/temp.expl.spec/p5.cpp
@@ -0,0 +1,61 @@
+// RUN: clang-cc -fsyntax-only -verify %s
+
+struct IntHolder {
+  IntHolder(int);
+};
+
+template<typename T, typename U>
+struct X {
+  void f() { 
+    T t;
+  }
+  
+  void g() { }
+  
+  struct Inner { 
+    T value; 
+  };
+  
+  static T value;
+};
+
+template<typename T, typename U>
+T X<T, U>::value;
+
+// Explicitly specialize the members of X<IntHolder, long> to not cause
+// problems with instantiation, but only provide declarations (not definitions).
+template<>
+void X<IntHolder, long>::f();
+
+template<>
+struct X<IntHolder, long>::Inner; // expected-note{{forward declaration}}
+
+template<>
+IntHolder X<IntHolder, long>::value;
+
+IntHolder &test_X_IntHolderInt(X<IntHolder, long> xih) {
+  xih.g(); // okay
+  xih.f(); // okay, uses specialization
+  
+  X<IntHolder, long>::Inner inner; // expected-error {{incomplete}}
+  
+  return X<IntHolder, long>::value; // okay, uses specialization
+}
+
+
+template<class T> struct A {
+  void f(T) { /* ... */ }
+};
+
+template<> struct A<int> { 
+  void f(int);
+};
+
+void h() {
+  A<int> a; 
+  a.f(16); // A<int>::f must be defined somewhere
+}
+
+// explicit specialization syntax not used for a member of 
+// explicitly specialized class template specialization 
+void A<int>::f(int) { /* ... */ }