File: invalid-requirement-requires-expr.cpp

package info (click to toggle)
llvm-toolchain-17 1%3A17.0.6-22
  • links: PTS, VCS
  • area: main
  • in suites: forky, sid, trixie
  • size: 1,799,624 kB
  • sloc: cpp: 6,428,607; ansic: 1,383,196; asm: 793,408; python: 223,504; objc: 75,364; f90: 60,502; lisp: 33,869; pascal: 15,282; sh: 9,684; perl: 7,453; ml: 4,937; awk: 3,523; makefile: 2,889; javascript: 2,149; xml: 888; fortran: 619; cs: 573
file content (27 lines) | stat: -rw-r--r-- 953 bytes parent folder | download | duplicates (13) 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
 
// RUN: %clang -fsyntax-only -std=c++2a -Xclang -verify -ftemplate-depth=5 -ftemplate-backtrace-limit=4 %s

// RequiresExpr contains invalid requirement. (Eg. Highly recurisive template).
template<int x>
struct A { static constexpr bool far(); };
class B {
    bool data_member;
    friend struct A<1>;
};

template<>
constexpr bool A<0>::far() { return true; }

template<int x>
constexpr bool A<x>::far() {
    return requires(B b) {
      b.data_member;
      requires A<x-1>::far(); // #Invalid
      // expected-error@#Invalid {{recursive template instantiation exceeded maximum depth}}
      // expected-note@#Invalid {{in instantiation}}
      // expected-note@#Invalid 2 {{while}}
      // expected-note@#Invalid {{contexts in backtrace}}
      // expected-note@#Invalid {{increase recursive template instantiation depth}}
    };
}
static_assert(A<1>::far());
static_assert(!A<6>::far()); // expected-note {{in instantiation of member function}}