template<class> struct Base { };

struct Derived : Base<void> { };

template<template<typename> class TT, typename T>
void func (TT<T>) { }

int main () {
  func (Derived { });
}


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main.cpp: In function 'int main()':
main.cpp:9:20: error: no matching function for call to 'func(Derived)'
   func (Derived { });
                    ^
main.cpp:9:20: note: candidate is:
main.cpp:6:6: note: template<template<class> class TT, class T> void func(TT<T>)
 void func (TT<T>) { }
      ^
main.cpp:6:6: note:   template argument deduction/substitution failed:
main.cpp:9:20: note:   can't deduce a template for 'TT<T>' from non-template type 'Derived'
   func (Derived { });

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gcc rejects the snippet which is a violation of [temp.deduct.call]/4 (`clang` and `msvc` accepts the code).

`TT<T>` is a `simple-template-id` and the standard says that if a derived type is passed to such context it should be deduced to a suitable base of that passed type. 

Correct behavior is that the deduced template parameters for `func (Derived {})` should be `TT = Base, T = void`.