clang/test/CXX/basic/basic.lookup/basic.lookup.argdep/p5-ex2.cpp

   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 {{declaration of 'R' must be imported from module 'N' before it is required}}
  54   // expected-note@N.cpp:4 {{declaration here is not visible}}
  55   // expected-error@-2 {{no type named 'f' in namespace 'R'}}
  56
  57   f(x); // Found by [basic.lookup.argdep] / p4.3
  58
  59   // error: S::f in module M not considered even though S is an associated
  60   // namespace, since the entity Z is in a different module from f.
  61   f(x, S::Z()); // expected-error {{no matching function for call to 'f'}}
  62   // expected-note@M.cpp:4 {{candidate function not viable: requires 1 argument, but 2 were provided}}
  63
  64   // error: S::f is visible in instantiation context, but  R::g has internal
  65   // linkage and cannot be used outside N.cpp
  66   apply(x, S::Z()); // expected-error@N.cpp:10 {{no matching function for call to 'g'}}
  67                     // expected-note@-1 {{in instantiation of function template specialization 'apply<R::X, S::Z>' requested here}}
  68 }