50fdd7df82
Add coverage to demonstrate why including the type of template parameters is necessary to disambiguate function template specializations. Test courtesy of Richard Smith
107 lines
3.0 KiB
C++
107 lines
3.0 KiB
C++
// RUN: %clang_cc1 -std=c++1z -ast-print %s > %t
|
|
// RUN: FileCheck < %t %s -check-prefix=CHECK1
|
|
// RUN: FileCheck < %t %s -check-prefix=CHECK2
|
|
// RUN: %clang_cc1 -std=c++1z -ast-dump %s | FileCheck --check-prefix=DUMP %s
|
|
|
|
template <int X, typename Y, int Z = 5>
|
|
struct foo {
|
|
int constant;
|
|
foo() {}
|
|
Y getSum() { return Y(X + Z); }
|
|
};
|
|
|
|
template <int A, typename B>
|
|
B bar() {
|
|
return B(A);
|
|
}
|
|
|
|
void baz() {
|
|
int x = bar<5, int>();
|
|
int y = foo<5, int>().getSum();
|
|
double z = foo<2, double, 3>().getSum();
|
|
}
|
|
|
|
// Template definition - foo
|
|
// CHECK1: template <int X, typename Y, int Z = 5> struct foo {
|
|
// CHECK2: template <int X, typename Y, int Z = 5> struct foo {
|
|
|
|
// Template instantiation - foo
|
|
// Since the order of instantiation may vary during runs, run FileCheck twice
|
|
// to make sure each instantiation is in the correct spot.
|
|
// CHECK1: template<> struct foo<5, int, 5> {
|
|
// CHECK2: template<> struct foo<2, double, 3> {
|
|
|
|
// Template definition - bar
|
|
// CHECK1: template <int A, typename B> B bar()
|
|
// CHECK2: template <int A, typename B> B bar()
|
|
|
|
// Template instantiation - bar
|
|
// CHECK1: template<> int bar<5, int>()
|
|
// CHECK2: template<> int bar<5, int>()
|
|
|
|
// CHECK1-LABEL: template <typename ...T> struct A {
|
|
// CHECK1-NEXT: template <T ...x[3]> struct B {
|
|
template <typename ...T> struct A {
|
|
template <T ...x[3]> struct B {};
|
|
};
|
|
|
|
// CHECK1-LABEL: template <typename ...T> void f(T ...[3]) {
|
|
// CHECK1-NEXT: A<T[3]...> a;
|
|
template <typename ...T> void f(T ...[3]) {
|
|
A<T[3]...> a;
|
|
}
|
|
|
|
namespace test2 {
|
|
void func(int);
|
|
void func(float);
|
|
template<typename T>
|
|
void tmpl() {
|
|
func(T());
|
|
}
|
|
|
|
// DUMP: UnresolvedLookupExpr {{.*}} <col:3> '<overloaded function type>' lvalue (ADL) = 'func'
|
|
}
|
|
|
|
namespace test3 {
|
|
template<typename T> struct A {};
|
|
template<typename T> A(T) -> A<int>;
|
|
// CHECK1: template <typename T> A(T) -> A<int>;
|
|
}
|
|
|
|
namespace test4 {
|
|
template <unsigned X, auto A>
|
|
struct foo {
|
|
static void fn();
|
|
};
|
|
|
|
// Prints using an "integral" template argument. Test that this correctly
|
|
// includes the type for the auto argument and omits it for the fixed
|
|
// type/unsigned argument (see
|
|
// TemplateParameterList::shouldIncludeTypeForArgument)
|
|
// CHECK1: {{^ }}template<> struct foo<0, 0L> {
|
|
// CHECK1: {{^ }}void test(){{ }}{
|
|
// CHECK1: {{^ }}foo<0, 0 + 0L>::fn();
|
|
void test() {
|
|
foo<0, 0 + 0L>::fn();
|
|
}
|
|
|
|
// Prints using an "expression" template argument. This renders based on the way
|
|
// the user wrote the arguments (including that + expression) - so it's not
|
|
// powered by the shouldIncludeTypeForArgument functionality.
|
|
// Not sure if this it's intentional that these two specializations are rendered
|
|
// differently in this way.
|
|
// CHECK1: {{^ }}template<> struct foo<1, 0 + 0L> {
|
|
template struct foo<1, 0 + 0L>;
|
|
}
|
|
|
|
namespace test5 {
|
|
template<long> void f() {}
|
|
void (*p)() = f<0>;
|
|
template<unsigned = 0> void f() {}
|
|
void (*q)() = f<>;
|
|
// Not perfect - this code in the dump would be ambiguous, but it's the best we
|
|
// can do to differentiate these two implicit specializations.
|
|
// CHECK1: template<> void f<0L>()
|
|
// CHECK1: template<> void f<0U>()
|
|
}
|