Fix http://stackoverflow.com/questions/13521163

Don't require that, during template deduction, a template specialization type
as a function parameter has at least as many template arguments as one used in
a function argument (not even if the argument has been resolved to an exact
type); the additional parameters might be provided by default template
arguments in the template. We don't need this check, since we now implement
[temp.deduct.call]p4 with an additional check after deduction.

llvm-svn: 169475

1 files changed, 13 insertions, 0 deletions

diff --git a/clang/test/CXX/temp/temp.fct.spec/temp.deduct/temp.deduct.type/p9-0x.cpp b/clang/test/CXX/temp/temp.fct.spec/temp.deduct/temp.deduct.type/p9-0x.cpp
index 7774b5c77fa..d7989e305f0 100644
--- a/clang/test/CXX/temp/temp.fct.spec/temp.deduct/temp.deduct.type/p9-0x.cpp
+++ b/clang/test/CXX/temp/temp.fct.spec/temp.deduct/temp.deduct.type/p9-0x.cpp
@@ -53,3 +53,16 @@ namespace DeduceNonTypeTemplateArgsInArray {
                      tuple<unsigned_c<1>, unsigned_c<2>, unsigned_c<3>>
                      >::value? 1 : -1];
 }
+
+namespace DeduceWithDefaultArgs {
+  template<template<typename...> class Container> void f(Container<int>); // expected-note {{substitution failure [with Container = X]}}
+  template<typename, typename = int> struct X {};
+  void g() {
+    // OK, use default argument for the second template parameter.
+    f(X<int>{});
+    f(X<int, int>{});
+
+    // Not OK.
+    f(X<int, double>{}); // expected-error {{no matching function for call to 'f'}}
+  }
+}