Fix an edge case in the template differ with default arguments.

In the test case one type is coming from a typedef with no default arg, the
other has the default arg. Taking the default arg from the typedef crashes, so
always use the real template paramter declaration. PR17510.

llvm-svn: 192202

1 files changed, 17 insertions, 1 deletions

diff --git a/clang/test/Misc/diag-template-diffing.cpp b/clang/test/Misc/diag-template-diffing.cpp
index 722ce98ecff..46807070c7c 100644
--- a/clang/test/Misc/diag-template-diffing.cpp
+++ b/clang/test/Misc/diag-template-diffing.cpp
@@ -1051,8 +1051,24 @@ namespace DependentInt {
   }
 }
 
+namespace PR17510 {
+class Atom;
+
+template <typename T> class allocator;
+template <typename T, typename A> class vector;
+
+typedef vector<const Atom *, allocator<const Atom *> > AtomVector;
+
+template <typename T, typename A = allocator<const Atom *> > class vector {};
+
+void foo() {
+  vector<Atom *> v;
+  AtomVector v2(v);
+  // CHECK-ELIDE-NOTREE: no known conversion from 'vector<class PR17510::Atom *, [...]>' to 'const vector<const class PR17510::Atom *, [...]>'
+}
+}
+
 // CHECK-ELIDE-NOTREE: {{[0-9]*}} errors generated.
 // CHECK-NOELIDE-NOTREE: {{[0-9]*}} errors generated.
 // CHECK-ELIDE-TREE: {{[0-9]*}} errors generated.
 // CHECK-NOELIDE-TREE: {{[0-9]*}} errors generated.
-