p5.cpp revision 745f5147e065900267c85a5568785a1991d4838f
15821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// RUN: %clang_cc1 -fsyntax-only -verify -std=c++11 -fcxx-exceptions %s 25821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 35821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)namespace StdExample { 45821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 55821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)constexpr int f(void *) { return 0; } 65821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)constexpr int f(...) { return 1; } 75821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)constexpr int g1() { return f(0); } 85821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)constexpr int g2(int n) { return f(n); } 95821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)constexpr int g3(int n) { return f(n*0); } 105821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 115821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)namespace N { 125821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) constexpr int c = 5; 132a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) constexpr int h() { return c; } 145821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 155821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)constexpr int c = 0; 165821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)constexpr int g4() { return N::h(); } 175821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 185821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)static_assert(f(0) == 0, ""); 195821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)static_assert(f('0') == 1, ""); 205821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)static_assert(g1() == 0, ""); 215821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)static_assert(g2(0) == 1, ""); 225821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)static_assert(g2(1) == 1, ""); 235821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)static_assert(g3(0) == 1, ""); 245821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)static_assert(g3(1) == 1, ""); 252a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles)static_assert(N::h() == 5, ""); 265821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)static_assert(g4() == 5, ""); 275821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 285821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 292a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles)constexpr int f(bool b) 30c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) { return b ? throw 0 : 0; } // ok 312a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles)constexpr int f() { return throw 0, 0; } // expected-error {{constexpr function never produces a constant expression}} expected-note {{subexpression}} 322a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) 33c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles)struct B { 345d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) constexpr B(int x) : i(0) { } 352a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) int i; 365821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)}; 375821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 385f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)int global; // expected-note {{declared here}} 395821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 405821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)struct D : B { 415821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) constexpr D() : B(global) { } // expected-error {{constexpr constructor never produces a constant expression}} expected-note {{read of non-const}} 425821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)}; 435821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 445821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 455821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 465821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)namespace PotentialConstant { 475821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 485821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)constexpr int Comma(int n) { return // expected-error {{constexpr function never produces a constant expression}} 495821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) (void)(n * 2), 505821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) throw 0, // expected-note {{subexpression}} 515821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 0; 525821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 53 54int ng; // expected-note 5{{here}} 55constexpr int BinaryOp1(int n) { return n + ng; } // expected-error {{never produces}} expected-note {{read}} 56constexpr int BinaryOp2(int n) { return ng + n; } // expected-error {{never produces}} expected-note {{read}} 57 58double dg; // expected-note 2{{here}} 59constexpr double BinaryOp1(double d) { return d + dg; } // expected-error {{never produces}} expected-note {{read}} 60constexpr double BinaryOp2(double d) { return dg + d; } // expected-error {{never produces}} expected-note {{read}} 61 62constexpr int Add(int a, int b, int c) { return a + b + c; } 63constexpr int FunctionArgs(int a) { return Add(a, ng, a); } // expected-error {{never produces}} expected-note {{read}} 64 65struct S { int a; int b; int c[2]; }; 66constexpr S InitList(int a) { return { a, ng }; }; // expected-error {{never produces}} expected-note {{read}} 67constexpr S InitList2(int a) { return { a, a, { ng } }; }; // expected-error {{never produces}} expected-note {{read}} 68 69constexpr S InitList3(int a) { return a ? (S){ a, a } : (S){ a, ng }; }; // ok 70 71// FIXME: Check both arms of a ?: if the conditional is a potential constant 72// expression with an unknown value, and diagnose if neither is constant. 73constexpr S InitList4(int a) { return a ? (S){ a, ng } : (S){ a, ng }; }; 74 75} 76