xref: /llvm-project/clang/test/CXX/basic/basic.lookup/basic.lookup.argdep/p5-ex2.cpp (revision fb2c9d940ad87e6ae09e06c6915e0c925a4f87ec)
1 // RUN: rm -rf %t
2 // RUN: mkdir -p %t
3 // RUN: split-file %s %t
4 // RUN: cd %t
5 //
6 // RUN: %clang_cc1 -std=c++20 M.cpp -emit-module-interface -o M.pcm
7 // RUN: %clang_cc1 -std=c++20 N.cpp -emit-module-interface -o N.pcm \
8 // RUN:   -fmodule-file=M=M.pcm
9 // RUN: %clang_cc1 -std=c++20 Q.cpp -emit-module-interface -o Q.pcm
10 // RUN: %clang_cc1 -std=c++20 Q-impl.cpp -fsyntax-only -fmodule-file=Q=Q.pcm \
11 // RUN:   -fmodule-file=N=N.pcm -fmodule-file=M=M.pcm -verify
12 
13 //--- M.cpp
14 export module M;
15 namespace R {
16 export struct X {};
17 export void f(X);
18 } // namespace R
19 namespace S {
20 export void f(R::X, R::X);
21 }
22 
23 //--- N.cpp
24 export module N;
25 import M;
26 export R::X make();
27 namespace R {
28 static int g(X);
29 }
30 export template <typename T, typename U>
31 void apply(T t, U u) {
32   f(t, u);
33   g(t);
34 }
35 
36 //--- Q.cpp
37 export module Q;
38 
39 //--- Q-impl.cpp
40 module Q;
41 import N;
42 
43 namespace S {
44 struct Z {
45   template <typename T> operator T();
46 };
47 } // namespace S
48 void test() {
49   // OK, decltype(x) is R::X in module M
50   auto x = make();
51 
52   // error: R and R::f are not visible here
53   R::f(x); // expected-error {{no type named 'f' in namespace 'R'}}
54 
55   f(x); // Found by [basic.lookup.argdep] / p4.3
56 
57   // error: S::f in module M not considered even though S is an associated
58   // namespace, since the entity Z is in a different module from f.
59   f(x, S::Z()); // expected-error {{no matching function for call to 'f'}}
60   // expected-note@M.cpp:4 {{candidate function not viable: requires 1 argument, but 2 were provided}}
61 
62   // error: S::f is visible in instantiation context, but  R::g has internal
63   // linkage and cannot be used outside N.cpp
64   apply(x, S::Z()); // expected-error@N.cpp:10 {{use of undeclared identifier 'g'}}
65                     // expected-note@-1 {{requested here}}
66 }
67