1 // RUN: %clang_cc1 -std=c++2a -emit-pch %s -o %t
2 // RUN: %clang_cc1 -std=c++2a -include-pch %t -verify %s
3 
4 // expected-no-diagnostics
5 
6 #ifndef HEADER
7 #define HEADER
8 
9 auto l1 = []<int I>() constexpr -> int {
10     return I;
11 };
12 
13 auto l2 = []<auto I>() constexpr -> decltype(I) {
14     return I;
15 };
16 
17 auto l3 = []<class T>(auto i) constexpr -> T {
18   return T(i);
19 };
20 
21 auto l4 = []<template<class> class T, class U>(T<U>, auto i) constexpr -> U {
22   return U(i);
23 };
24 
25 #else /*included pch*/
26 
27 static_assert(l1.operator()<5>() == 5);
28 static_assert(l1.operator()<6>() == 6);
29 
30 static_assert(l2.operator()<7>() == 7);
31 static_assert(l2.operator()<nullptr>() == nullptr);
32 
33 static_assert(l3.operator()<int>(8.4) == 8);
34 static_assert(l3.operator()<int>(9.9) == 9);
35 
36 template<typename T>
37 struct DummyTemplate { };
38 
39 static_assert(l4(DummyTemplate<float>(), 12) == 12.0);
40 static_assert(l4(DummyTemplate<int>(), 19.8) == 19);
41 
42 #endif // HEADER
43