clang/test/Modules/template-function-specialization.cpp

   1 // RUN: rm -fr %t
   2 // RUN: mkdir %t
   3 // RUN: split-file %s %t
   4 //
   5 // RUN: %clang_cc1 -std=c++20 -emit-module-interface %t/foo.cppm -o %t/foo.pcm
   6 // RUN: %clang_cc1 -std=c++20 -fprebuilt-module-path=%t %t/Use.cpp -verify -fsyntax-only
   7
   8 // RUN: %clang_cc1 -std=c++20 -emit-reduced-module-interface %t/foo.cppm -o %t/foo.pcm
   9 // RUN: %clang_cc1 -std=c++20 -fprebuilt-module-path=%t %t/Use.cpp -verify -fsyntax-only -DREDUCED
  10
  11 //--- foo.cppm
  12 module;
  13 # 3 __FILE__ 1 // use the next physical line number here (and below)
  14 template <typename T>
  15 void foo() {
  16 }
  17
  18 template <>
  19 void foo<int>() {
  20 }
  21
  22 template <typename T>
  23 void foo2() {
  24 }
  25
  26 template <>
  27 void foo2<int>() {
  28 }
  29
  30 template <typename T>
  31 void foo3() {
  32 }
  33
  34 template <>
  35 void foo3<int>();
  36
  37 export module foo;
  38 export using ::foo;
  39 export using ::foo3;
  40
  41 export template <typename T>
  42 void foo4() {
  43 }
  44
  45 export template <>
  46 void foo4<int>() {
  47 }
  48
  49 //--- Use.cpp
  50 import foo;
  51 void use() {
  52   foo<short>();
  53   foo<int>();
  54 #ifdef REDUCED
  55   // In reduced BMI, the foo2 template function is optimized out.
  56   foo2<short>(); // expected-error {{use of undeclared identifier 'foo2'}}
  57   foo2<int>();   // expected-error {{use of undeclared identifier 'foo2'}}
  58 #else
  59   foo2<short>(); // expected-error {{missing '#include'; 'foo2' must be declared before it is used}}
  60                  // expected-note@* {{declaration here is not visible}}
  61   foo2<int>();   // expected-error {{missing '#include'; 'foo2' must be declared before it is used}}
  62                  // expected-note@* {{declaration here is not visible}}
  63 #endif
  64   foo3<short>();
  65   foo3<int>();
  66
  67   foo4<short>();
  68   foo4<int>();
  69 }