1 // RUN: %clang_cc1 -fsyntax-only -verify -Wno-unused-value -std=c++20 %s
2
3 namespace std {
4 typedef decltype(sizeof(int)) size_t;
5
6 template <typename E>
7 struct initializer_list {
8 const E *p;
9 size_t n;
initializer_liststd::initializer_list10 initializer_list(const E *p, size_t n) : p(p), n(n) {}
11 };
12
13 // Classes to use to reproduce the exact scenario present in #62925.
14 template<class T, class Y>
15 class pair {
16 public:
pair(T f,Y s)17 pair(T f, Y s) {}
18 };
19
20 template<class T, class Y>
21 class map {
22 public:
map(std::initializer_list<pair<T,Y>>)23 map(std::initializer_list<pair<T, Y>>) {}
map(std::initializer_list<pair<T,Y>>,int a)24 map(std::initializer_list<pair<T, Y>>, int a) {}
25 };
26
27 } // namespace std
28
29 // This is the almost the exact code that was in issue #62925.
testOneLevelNesting()30 void testOneLevelNesting() {
31 std::map mOk = {std::pair{5, 'a'}, {6, 'b'}, {7, 'c'}};
32
33 // Verify that narrowing conversion is disabled in the first level of nesting.
34 std::map mNarrow = {std::pair{5, 'a'}, {6.0f, 'b'}, {7, 'c'}}; // expected-error {{type 'float' cannot be narrowed to 'int' in initializer list}} // expected-note {{insert an explicit cast to silence this issue}}
35 }
36
testMultipleLevelNesting()37 void testMultipleLevelNesting() {
38 std::map aOk = {{std::pair{5, 'c'}, {5, 'c'}}, 5};
39
40 // Verify that narrowing conversion is disabled when it is not in a nested
41 // in another std::initializer_list, but it happens in the most outer one.
42 std::map aNarrowNested = {{std::pair{5, 'c'}, {5.0f, 'c'}}, 5}; // expected-error {{type 'float' cannot be narrowed to 'int' in initializer list}} // expected-note {{insert an explicit cast to silence this issue}}
43
44 // Verify that narrowing conversion is disabled in the first level of nesting.
45 std::map aNarrow = {{std::pair{5, 'c'}, {5, 'c'}}, 5.0f}; // expected-error {{type 'float' cannot be narrowed to 'int' in initializer list}} // expected-note {{insert an explicit cast to silence this issue}}
46 }
47