clang/test/SemaCXX/compare-function-pointer.cpp

   1 // RUN: %clang_cc1 -fsyntax-only -std=c++20 -verify %s
   2
   3 using fp0_t = void (*)();
   4 using fp1_t = int (*)();
   5
   6 extern fp0_t a, b;
   7 extern fp1_t c;
   8
   9 bool eq0 = a == b;
  10 bool ne0 = a != b;
  11 bool lt0 = a < b;   // expected-warning {{ordered comparison of function pointers ('fp0_t' (aka 'void (*)()') and 'fp0_t')}}
  12 bool le0 = a <= b;  // expected-warning {{ordered comparison of function pointers}}
  13 bool gt0 = a > b;   // expected-warning {{ordered comparison of function pointers}}
  14 bool ge0 = a >= b;  // expected-warning {{ordered comparison of function pointers}}
  15 auto tw0 = a <=> b; // expected-error {{ordered comparison of function pointers}}
  16
  17 bool eq1 = a == c;  // expected-error {{comparison of distinct pointer types}}
  18 bool ne1 = a != c;  // expected-error {{comparison of distinct pointer types}}
  19 bool lt1 = a < c;   // expected-warning {{ordered comparison of function pointers ('fp0_t' (aka 'void (*)()') and 'fp1_t' (aka 'int (*)()'))}}
  20                     // expected-error@-1 {{comparison of distinct pointer types}}
  21 bool le1 = a <= c;  // expected-warning {{ordered comparison of function pointers}}
  22                     // expected-error@-1 {{comparison of distinct pointer types}}
  23 bool gt1 = a > c;   // expected-warning {{ordered comparison of function pointers}}
  24                     // expected-error@-1 {{comparison of distinct pointer types}}
  25 bool ge1 = a >= c;  // expected-warning {{ordered comparison of function pointers}}
  26                     // expected-error@-1 {{comparison of distinct pointer types}}
  27 auto tw1 = a <=> c; // expected-error {{ordered comparison of function pointers}}