opnsense-src/test/SemaTemplate/function-template-specialization.cpp

// RUN: clang-cc -fsyntax-only -verify %s

template<int N> void f0(int (&array)[N]);

// Simple function template specialization (using overloading)
template<> void f0(int (&array)[1]);

void test_f0() {
  int iarr1[1];
  f0(iarr1);
}

// Function template specialization where there are no matches
template<> void f0(char (&array)[1]); // expected-error{{no function template matches}}
template<> void f0<2>(int (&array)[2]) { }

// Function template specialization that requires partial ordering
template<typename T, int N> void f1(T (&array)[N]); // expected-note{{matches}}
template<int N> void f1(int (&array)[N]); // expected-note{{matches}}

template<> void f1(float (&array)[1]);
template<> void f1(int (&array)[1]);

// Function template specialization that results in an ambiguity
template<typename T> void f1(T (&array)[17]); // expected-note{{matches}}
template<> void f1(int (&array)[17]); // expected-error{{ambiguous}}

// Resolving that ambiguity with explicitly-specified template arguments.
template<int N> void f2(double (&array)[N]);
template<typename T> void f2(T (&array)[42]);

template<> void f2<double>(double (&array)[42]);
template<> void f2<42>(double (&array)[42]);

void f2<25>(double (&array)[25]); // expected-error{{specialization}}