clang/test/Modules/string-literal-uniqueness.cpp

   1 // RUN: rm -rf %t
   2 // RUN: mkdir -p %t
   3 // RUN: split-file %s %t
   4
   5 // RUN: %clang_cc1 -std=c++20 -emit-module-interface %t/a.cpp \
   6 // RUN:  -o %t/A.pcm
   7
   8 // RUN: %clang_cc1 -std=c++20 -emit-module-interface %t/b.cpp \
   9 // RUN:  -fmodule-file=A=%t/A.pcm -o %t/B.pcm
  10
  11 // RUN: %clang_cc1 -std=c++20 -emit-module-interface %t/c.cpp \
  12 // RUN:  -fmodule-file=A=%t/A.pcm -o %t/C.pcm
  13
  14 // RUN: %clang_cc1 -std=c++20 -verify %t/main.cpp \
  15 // RUN:  -fmodule-file=A=%t/A.pcm \
  16 // RUN:  -fmodule-file=B=%t/B.pcm \
  17 // RUN:  -fmodule-file=C=%t/C.pcm
  18
  19 // expected-no-diagnostics
  20
  21 //--- a.cpp
  22
  23 export module A;
  24 export consteval const char *hello() { return "hello"; }
  25 export constexpr const char *helloA0 = hello();
  26 export constexpr const char *helloA1 = helloA0;
  27 export constexpr const char *helloA2 = hello();
  28
  29 //--- b.cpp
  30
  31 export module B;
  32 import A;
  33 export constexpr const char *helloB1 = helloA0;
  34 export constexpr const char *helloB2 = hello();
  35
  36 //--- c.cpp
  37
  38 export module C;
  39 import A;
  40 export constexpr const char *helloC1 = helloA1;
  41 export constexpr const char *helloC2 = hello();
  42
  43 //--- main.cpp
  44
  45 import A;
  46 import B;
  47 import C;
  48
  49 // These are valid: they refer to the same evaluation of the same constant.
  50 static_assert(helloA0 == helloA1);
  51 static_assert(helloA0 == helloB1);
  52 static_assert(helloA0 == helloC1);
  53
  54 // These refer to distinct evaluations, and so may or may not be equal.
  55 static_assert(helloA1 == helloA2); // expected-error {{}} expected-note {{unspecified value}}
  56 static_assert(helloA1 == helloB2); // expected-error {{}} expected-note {{unspecified value}}
  57 static_assert(helloA1 == helloC2); // expected-error {{}} expected-note {{unspecified value}}
  58 static_assert(helloA2 == helloB2); // expected-error {{}} expected-note {{unspecified value}}
  59 static_assert(helloA2 == helloC2); // expected-error {{}} expected-note {{unspecified value}}
  60 static_assert(helloB2 == helloC2); // expected-error {{}} expected-note {{unspecified value}}