Semantic checking for class template declarations and

redeclarations. For example, checks that a class template
redeclaration has the same template parameters as previous
declarations.

Detangled class-template checking from ActOnTag, whose logic was
getting rather convoluted because it tried to handle C, C++, and C++
template semantics in one shot.

Made some inroads toward eliminating extraneous "declaration does not
declare anything" errors by adding an "error" type specifier.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@63973 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 52 insertions, 0 deletions

diff --git a/test/SemaTemplate/class-template-decl.cpp b/test/SemaTemplate/class-template-decl.cpp
new file mode 100644
index 0000000000..3978e1f04a
--- /dev/null
+++ b/test/SemaTemplate/class-template-decl.cpp
@@ -0,0 +1,52 @@
+// RUN: clang -fsyntax-only -verify %s
+
+template<typename T> class A;
+
+extern "C++" {
+  template<typename T> class B;
+}
+
+namespace N {
+  template<typename T> class C;
+}
+
+extern "C" {
+  template<typename T> class D; // expected-error{{templates must have C++ linkage}}
+}
+
+template<class U> class A; // expected-note{{previous template declaration is here}}\
+                           // expected-note{{previous use is here}}
+
+template<int N> class A; // expected-error{{template parameter has a different kind in template redeclaration}}
+
+template<class T> struct A; // expected-error{{use of 'A' with tag type that does not match previous declaration}}
+
+template<int N> class NonTypeTemplateParm;
+
+typedef int INT;
+
+template<INT M> class NonTypeTemplateParm; // expected-note{{previous non-type template parameter with type 'INT' is here}}
+
+template<long> class NonTypeTemplateParm; // expected-error{{template non-type parameter has a different type 'long' in template redeclaration}}
+
+template<template<typename T> class X> class TemplateTemplateParm;
+
+template<template<class> class Y> class TemplateTemplateParm; // expected-note{{previous template declaration is here}} \
+      // expected-note{{previous template template parameter is here}}
+
+template<typename> class TemplateTemplateParm; // expected-error{{template parameter has a different kind in template redeclaration}}
+
+template<template<typename T, int> class X> class TemplateTemplateParm; // expected-error{{too many template parameters in template template parameter redeclaration}}
+
+#if 0
+// FIXME: parse template declarations in these scopes, so that we can
+// complain about the one at function scope.
+class X {
+public:
+  template<typename T> class C;
+};
+
+void f() {
+  template<typename T> class X;
+}
+#endif