Improve diagnostics and error recovery for template name lookup.

For 'x::template y', consistently give a "no member named 'y' in 'x'"
diagnostic if there is no such member, and give a 'template keyword not
followed by a template' name error if there is such a member but it's not a
template. In the latter case, add a note pointing at the non-template.

Don't suggest inserting a 'template' keyword in 'X::Y<' if X is dependent
if the lookup of X::Y was actually not a dependent lookup and found only
non-templates.

llvm-svn: 332076

1 files changed, 31 insertions, 4 deletions

diff --git a/clang/test/SemaTemplate/typo-dependent-name.cpp b/clang/test/SemaTemplate/typo-dependent-name.cpp
index 78cedd0c98c..0231740f6c2 100644
--- a/clang/test/SemaTemplate/typo-dependent-name.cpp
+++ b/clang/test/SemaTemplate/typo-dependent-name.cpp
@@ -1,18 +1,45 @@
 // RUN: %clang_cc1 -fsyntax-only -verify %s
-// expected-no-diagnostics
+
+using nullptr_t = decltype(nullptr);
 
 template<typename T>
 struct Base {
   T inner;
 };
 
+int z;
+
 template<typename T>
-struct X {
-  template<typename U>
+struct X : Base<T> {
+  static int z;
+
+  template<int U>
   struct Inner {
   };
 
   bool f(T other) {
-    return this->inner < other;
+    // A pair of comparisons; 'inner' is a dependent name so can't be assumed
+    // to be a template.
+    return this->inner < other > ::z;
   }
 };
+
+void use_x(X<int> x) { x.f(0); }
+
+template<typename T>
+struct Y {
+  static int z;
+
+  template<int U>
+  struct Inner : Y { // expected-note {{declared here}}
+  };
+
+  bool f(T other) {
+    // We can determine that 'inner' does not exist at parse time, so can
+    // perform typo correction in this case.
+    return this->inner<other>::z; // expected-error {{no template named 'inner' in 'Y<T>'; did you mean 'Inner'?}}
+  }
+};
+
+struct Q { constexpr operator int() { return 0; } };
+void use_y(Y<Q> x) { x.f(Q()); }