Do not implicitly instantiate the definition of a class template specialization

that has been explicitly specialized!

We assume in various places that we can tell the template specialization kind
of a class type by looking at the declaration produced by TagType::getDecl.
That was previously not quite true: for an explicit specialization, we could
have first seen a template-id denoting the specialization (with a use that does
not trigger an implicit instantiation of the defintiion) and then seen the
first explicit specialization declaration. TagType::getDecl would previously
return an arbitrary declaration when called on a not-yet-defined class; it
now consistently returns the most recent declaration in that case.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@295118 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 11 insertions, 0 deletions

diff --git a/test/SemaTemplate/explicit-specialization-member.cpp b/test/SemaTemplate/explicit-specialization-member.cpp
index f302836c7e..4300ceb17e 100644
--- a/test/SemaTemplate/explicit-specialization-member.cpp
+++ b/test/SemaTemplate/explicit-specialization-member.cpp
@@ -57,3 +57,14 @@ template<typename T> struct Helper {
 template<typename T> void Helper<T>::func<2>() {} // expected-error {{cannot specialize a member}} \
                                                   // expected-error {{no function template matches}}
 }
+
+namespace b35070233 {
+  template <typename T> struct Cls {
+    static void f() {}
+  };
+
+  void g(Cls<int>);
+
+  template<> struct Cls<int>; // expected-note {{forward declaration}}
+  template<> void Cls<int>::f(); // expected-error {{incomplete type}}
+}