constant-expression-cxx11.cpp revision 30ae1ed71dc99a396b7ddba9cabe9846a0c4449d
1604fb38cd943649bee579103d17ca6cda4aad144Richard Smith// RUN: %clang_cc1 -triple i686-linux -Wno-string-plus-int -fsyntax-only -fcxx-exceptions -verify -std=c++11 -pedantic %s -Wno-comment 259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithnamespace StaticAssertFoldTest { 459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithint x; 69eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(++x, "test"); // expected-error {{not an integral constant expression}} 79eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(false, "test"); // expected-error {{test}} 859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 1059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 111d238ea926bbdd04356ce475934fcd4cac654c4bRichard Smithtypedef decltype(sizeof(char)) size_t; 121d238ea926bbdd04356ce475934fcd4cac654c4bRichard Smith 131d238ea926bbdd04356ce475934fcd4cac654c4bRichard Smithtemplate<typename T> constexpr T id(const T &t) { return t; } 141d238ea926bbdd04356ce475934fcd4cac654c4bRichard Smithtemplate<typename T> constexpr T min(const T &a, const T &b) { 151d238ea926bbdd04356ce475934fcd4cac654c4bRichard Smith return a < b ? a : b; 161d238ea926bbdd04356ce475934fcd4cac654c4bRichard Smith} 171d238ea926bbdd04356ce475934fcd4cac654c4bRichard Smithtemplate<typename T> constexpr T max(const T &a, const T &b) { 181d238ea926bbdd04356ce475934fcd4cac654c4bRichard Smith return a < b ? b : a; 191d238ea926bbdd04356ce475934fcd4cac654c4bRichard Smith} 201d238ea926bbdd04356ce475934fcd4cac654c4bRichard Smithtemplate<typename T, size_t N> constexpr T *begin(T (&xs)[N]) { return xs; } 211d238ea926bbdd04356ce475934fcd4cac654c4bRichard Smithtemplate<typename T, size_t N> constexpr T *end(T (&xs)[N]) { return xs + N; } 2259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 2359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithstruct MemberZero { 24840462670ba7a6bc26265a2306b35f2f0f01f51cRichard Smith constexpr int zero() const { return 0; } 2559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith}; 2659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 2759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithnamespace DerivedToVBaseCast { 2859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 2959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith struct U { int n; }; 3059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith struct V : U { int n; }; 3159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith struct A : virtual V { int n; }; 3259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith struct Aa { int n; }; 3359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith struct B : virtual A, Aa {}; 3459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith struct C : virtual A, Aa {}; 3559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith struct D : B, C {}; 3659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 3759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith D d; 3859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr B *p = &d; 3959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr C *q = &d; 40f15fda02e9c8c82b4a716618f4010b9af8bff796Richard Smith 419eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert((void*)p != (void*)q, ""); 429eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert((A*)p == (A*)q, ""); 439eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert((Aa*)p != (Aa*)q, ""); 4459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 4559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr B &pp = d; 4659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr C &qq = d; 479eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert((void*)&pp != (void*)&qq, ""); 489eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(&(A&)pp == &(A&)qq, ""); 499eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(&(Aa&)pp != &(Aa&)qq, ""); 5059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 5159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr V *v = p; 5259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr V *w = q; 5359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr V *x = (A*)p; 549eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(v == w, ""); 559eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(v == x, ""); 5659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 579eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert((U*)&d == p, ""); 589eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert((U*)&d == q, ""); 599eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert((U*)&d == v, ""); 609eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert((U*)&d == w, ""); 619eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert((U*)&d == x, ""); 6259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 6359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith struct X {}; 6459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith struct Y1 : virtual X {}; 6559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith struct Y2 : X {}; 6659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith struct Z : Y1, Y2 {}; 6759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith Z z; 689eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert((X*)(Y1*)&z != (X*)(Y2*)&z, ""); 6959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 7059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 71f64699e8db3946e21b5f4a0421cbc58a3e439599Richard Smithnamespace ConstCast { 72f64699e8db3946e21b5f4a0421cbc58a3e439599Richard Smith 73f64699e8db3946e21b5f4a0421cbc58a3e439599Richard Smithconstexpr int n1 = 0; 74f64699e8db3946e21b5f4a0421cbc58a3e439599Richard Smithconstexpr int n2 = const_cast<int&>(n1); 75f64699e8db3946e21b5f4a0421cbc58a3e439599Richard Smithconstexpr int *n3 = const_cast<int*>(&n1); 76f64699e8db3946e21b5f4a0421cbc58a3e439599Richard Smithconstexpr int n4 = *const_cast<int*>(&n1); 77f64699e8db3946e21b5f4a0421cbc58a3e439599Richard Smithconstexpr const int * const *n5 = const_cast<const int* const*>(&n3); 78f64699e8db3946e21b5f4a0421cbc58a3e439599Richard Smithconstexpr int **n6 = const_cast<int**>(&n3); 79f64699e8db3946e21b5f4a0421cbc58a3e439599Richard Smithconstexpr int n7 = **n5; 80f64699e8db3946e21b5f4a0421cbc58a3e439599Richard Smithconstexpr int n8 = **n6; 81f64699e8db3946e21b5f4a0421cbc58a3e439599Richard Smith 82f64699e8db3946e21b5f4a0421cbc58a3e439599Richard Smith} 83f64699e8db3946e21b5f4a0421cbc58a3e439599Richard Smith 8459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithnamespace TemplateArgumentConversion { 8559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith template<int n> struct IntParam {}; 8659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 8759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith using IntParam0 = IntParam<0>; 881d238ea926bbdd04356ce475934fcd4cac654c4bRichard Smith using IntParam0 = IntParam<id(0)>; 896180245e9f63d2927b185ec251fb75aba30f1cacRichard Smith using IntParam0 = IntParam<MemberZero().zero>; // expected-error {{did you mean to call it with no arguments?}} 9059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 9159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 9259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithnamespace CaseStatements { 9359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith void f(int n) { 9459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith switch (n) { 958ef7b203332b0c8d65876a1f5e6d1db4e6f40e4bRichard Smith case MemberZero().zero: // expected-error {{did you mean to call it with no arguments?}} expected-note {{previous}} 968ef7b203332b0c8d65876a1f5e6d1db4e6f40e4bRichard Smith case id(0): // expected-error {{duplicate case value '0'}} 9759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith return; 9859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith } 9959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith } 10059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 10159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 10259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithextern int &Recurse1; 10316581335fc32abcbc6ab14eda7af38cf759664b7Richard Smithint &Recurse2 = Recurse1; // expected-note {{declared here}} 10416581335fc32abcbc6ab14eda7af38cf759664b7Richard Smithint &Recurse1 = Recurse2; 105099e7f647ccda915513f2b2ec53352dc756082d3Richard Smithconstexpr int &Recurse3 = Recurse2; // expected-error {{must be initialized by a constant expression}} expected-note {{initializer of 'Recurse2' is not a constant expression}} 106099e7f647ccda915513f2b2ec53352dc756082d3Richard Smith 107099e7f647ccda915513f2b2ec53352dc756082d3Richard Smithextern const int RecurseA; 108099e7f647ccda915513f2b2ec53352dc756082d3Richard Smithconst int RecurseB = RecurseA; // expected-note {{declared here}} 109099e7f647ccda915513f2b2ec53352dc756082d3Richard Smithconst int RecurseA = 10; 110099e7f647ccda915513f2b2ec53352dc756082d3Richard Smithconstexpr int RecurseC = RecurseB; // expected-error {{must be initialized by a constant expression}} expected-note {{initializer of 'RecurseB' is not a constant expression}} 11159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 11259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithnamespace MemberEnum { 11359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith struct WithMemberEnum { 11459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith enum E { A = 42 }; 11559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith } wme; 11659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 1179eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(wme.A == 42, ""); 11859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 11959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 12059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithnamespace DefaultArguments { 12159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 12259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconst int z = int(); 12359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int Sum(int a = 0, const int &b = 0, const int *c = &z, char d = 0) { 12459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith return a + b + *c + d; 12559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 12659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconst int four = 4; 12759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int eight = 8; 12859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr const int twentyseven = 27; 1299eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(Sum() == 0, ""); 1309eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(Sum(1) == 1, ""); 1319eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(Sum(1, four) == 5, ""); 1329eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(Sum(1, eight, &twentyseven) == 36, ""); 1339eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(Sum(1, 2, &four, eight) == 15, ""); 13459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 13559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 13659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 13759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithnamespace Ellipsis { 13859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 13959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith// Note, values passed through an ellipsis can't actually be used. 14059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int F(int a, ...) { return a; } 1419eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(F(0) == 0, ""); 1429eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(F(1, 0) == 1, ""); 1439eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(F(2, "test") == 2, ""); 1449eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(F(3, &F) == 3, ""); 1457098cbd601ad915aed22d4b5850da99359f25bf3Richard Smithint k = 0; // expected-note {{here}} 1467098cbd601ad915aed22d4b5850da99359f25bf3Richard Smithstatic_assert(F(4, k) == 3, ""); // expected-error {{constant expression}} expected-note {{read of non-const variable 'k'}} 14759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 14859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 14959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 15059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithnamespace Recursion { 15159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr int fib(int n) { return n > 1 ? fib(n-1) + fib(n-2) : n; } 1529eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(fib(11) == 89, ""); 15359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 15459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr int gcd_inner(int a, int b) { 15559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith return b == 0 ? a : gcd_inner(b, a % b); 15659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith } 15759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr int gcd(int a, int b) { 15859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith return gcd_inner(max(a, b), min(a, b)); 15959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith } 16059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 1619eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(gcd(1749237, 5628959) == 7, ""); 16259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 16359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 16459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithnamespace FunctionCast { 16559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith // When folding, we allow functions to be cast to different types. Such 16659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith // cast functions cannot be called, even if they're constexpr. 16759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr int f() { return 1; } 16859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith typedef double (*DoubleFn)(); 16959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith typedef int (*IntFn)(); 170d7c56e1114bfe7d461786903bb720d2c6efc05a1Richard Smith int a[(int)DoubleFn(f)()]; // expected-error {{variable length array}} expected-warning{{C99 feature}} 17159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith int b[(int)IntFn(f)()]; // ok 17259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 17359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 17459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithnamespace StaticMemberFunction { 17559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith struct S { 17659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith static constexpr int k = 42; 17759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith static constexpr int f(int n) { return n * k + 2; } 17859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith } s; 17959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 18059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr int n = s.f(19); 1819eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(S::f(19) == 800, ""); 1829eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(s.f(19) == 800, ""); 1839eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(n == 800, ""); 1841bf9a9e6a5bdc0de7939908855dcddf46b661800Richard Smith 1851bf9a9e6a5bdc0de7939908855dcddf46b661800Richard Smith constexpr int (*sf1)(int) = &S::f; 1861bf9a9e6a5bdc0de7939908855dcddf46b661800Richard Smith constexpr int (*sf2)(int) = &s.f; 1871bf9a9e6a5bdc0de7939908855dcddf46b661800Richard Smith constexpr const int *sk = &s.k; 18859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 18959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 19059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithnamespace ParameterScopes { 19159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 19259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith const int k = 42; 19383587db1bda97f45d2b5a4189e584e2a18be511aRichard Smith constexpr const int &ObscureTheTruth(const int &a) { return a; } 194099e7f647ccda915513f2b2ec53352dc756082d3Richard Smith constexpr const int &MaybeReturnJunk(bool b, const int a) { // expected-note 2{{declared here}} 19583587db1bda97f45d2b5a4189e584e2a18be511aRichard Smith return ObscureTheTruth(b ? a : k); 19659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith } 1979eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(MaybeReturnJunk(false, 0) == 42, ""); // ok 19883587db1bda97f45d2b5a4189e584e2a18be511aRichard Smith constexpr int a = MaybeReturnJunk(true, 0); // expected-error {{constant expression}} expected-note {{read of variable whose lifetime has ended}} 19959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 20083587db1bda97f45d2b5a4189e584e2a18be511aRichard Smith constexpr const int MaybeReturnNonstaticRef(bool b, const int a) { 20183587db1bda97f45d2b5a4189e584e2a18be511aRichard Smith return ObscureTheTruth(b ? a : k); 20259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith } 2039eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(MaybeReturnNonstaticRef(false, 0) == 42, ""); // ok 20483587db1bda97f45d2b5a4189e584e2a18be511aRichard Smith constexpr int b = MaybeReturnNonstaticRef(true, 0); // ok 20559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 20659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr int InternalReturnJunk(int n) { 20783587db1bda97f45d2b5a4189e584e2a18be511aRichard Smith return MaybeReturnJunk(true, n); // expected-note {{read of variable whose lifetime has ended}} 20859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith } 209099e7f647ccda915513f2b2ec53352dc756082d3Richard Smith constexpr int n3 = InternalReturnJunk(0); // expected-error {{must be initialized by a constant expression}} expected-note {{in call to 'InternalReturnJunk(0)'}} 21059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 21159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr int LToR(int &n) { return n; } 21259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr int GrabCallersArgument(bool which, int a, int b) { 21359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith return LToR(which ? b : a); 21459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith } 2159eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(GrabCallersArgument(false, 1, 2) == 1, ""); 2169eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(GrabCallersArgument(true, 4, 8) == 8, ""); 21759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 21859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 21959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 22059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithnamespace Pointers { 22159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 22259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr int f(int n, const int *a, const int *b, const int *c) { 22359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith return n == 0 ? 0 : *a + f(n-1, b, c, a); 22459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith } 22559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 22659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith const int x = 1, y = 10, z = 100; 2279eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(f(23, &x, &y, &z) == 788, ""); 22859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 22959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr int g(int n, int a, int b, int c) { 23059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith return f(n, &a, &b, &c); 23159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith } 2329eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(g(23, x, y, z) == 788, ""); 23359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 23459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 23559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 23659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithnamespace FunctionPointers { 23759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 23859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr int Double(int n) { return 2 * n; } 23959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr int Triple(int n) { return 3 * n; } 24059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr int Twice(int (*F)(int), int n) { return F(F(n)); } 24159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr int Quadruple(int n) { return Twice(Double, n); } 24259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr auto Select(int n) -> int (*)(int) { 24359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith return n == 2 ? &Double : n == 3 ? &Triple : n == 4 ? &Quadruple : 0; 24459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith } 245099e7f647ccda915513f2b2ec53352dc756082d3Richard Smith constexpr int Apply(int (*F)(int), int n) { return F(n); } // expected-note {{subexpression}} 24659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 2479eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(1 + Apply(Select(4), 5) + Apply(Select(3), 7) == 42, ""); 24859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 249099e7f647ccda915513f2b2ec53352dc756082d3Richard Smith constexpr int Invalid = Apply(Select(0), 0); // expected-error {{must be initialized by a constant expression}} expected-note {{in call to 'Apply(0, 0)'}} 25059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 25159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 25259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 25359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithnamespace PointerComparison { 25459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 25559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithint x, y; 2569eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(&x == &y, "false"); // expected-error {{false}} 2579eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(&x != &y, ""); 25859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr bool g1 = &x == &y; 25959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr bool g2 = &x != &y; 26059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr bool g3 = &x <= &y; // expected-error {{must be initialized by a constant expression}} 26159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr bool g4 = &x >= &y; // expected-error {{must be initialized by a constant expression}} 26259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr bool g5 = &x < &y; // expected-error {{must be initialized by a constant expression}} 26359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr bool g6 = &x > &y; // expected-error {{must be initialized by a constant expression}} 26459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 26559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithstruct S { int x, y; } s; 2669eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(&s.x == &s.y, "false"); // expected-error {{false}} 2679eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(&s.x != &s.y, ""); 2689eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(&s.x <= &s.y, ""); 2699eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(&s.x >= &s.y, "false"); // expected-error {{false}} 2709eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(&s.x < &s.y, ""); 2719eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(&s.x > &s.y, "false"); // expected-error {{false}} 2729eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith 2739eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(0 == &y, "false"); // expected-error {{false}} 2749eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(0 != &y, ""); 27559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr bool n3 = 0 <= &y; // expected-error {{must be initialized by a constant expression}} 27659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr bool n4 = 0 >= &y; // expected-error {{must be initialized by a constant expression}} 27759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr bool n5 = 0 < &y; // expected-error {{must be initialized by a constant expression}} 27859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr bool n6 = 0 > &y; // expected-error {{must be initialized by a constant expression}} 27959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 2809eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(&x == 0, "false"); // expected-error {{false}} 2819eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(&x != 0, ""); 28259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr bool n9 = &x <= 0; // expected-error {{must be initialized by a constant expression}} 28359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr bool n10 = &x >= 0; // expected-error {{must be initialized by a constant expression}} 28459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr bool n11 = &x < 0; // expected-error {{must be initialized by a constant expression}} 28559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr bool n12 = &x > 0; // expected-error {{must be initialized by a constant expression}} 28659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 2879eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(&x == &x, ""); 2889eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(&x != &x, "false"); // expected-error {{false}} 2899eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(&x <= &x, ""); 2909eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(&x >= &x, ""); 2919eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(&x < &x, "false"); // expected-error {{false}} 2929eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(&x > &x, "false"); // expected-error {{false}} 29359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 29459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr S* sptr = &s; 295099e7f647ccda915513f2b2ec53352dc756082d3Richard Smithconstexpr bool dyncast = sptr == dynamic_cast<S*>(sptr); // expected-error {{constant expression}} expected-note {{dynamic_cast}} 29659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 2972fd5983e0da447291a651a347c206aee37a1de5fRichard Smithstruct U {}; 298c216a01c96d83bd9a90e214af64913e93d39aaccRichard Smithstruct Str { 299c216a01c96d83bd9a90e214af64913e93d39aaccRichard Smith int a : dynamic_cast<S*>(sptr) == dynamic_cast<S*>(sptr); // \ 300244ee7b89a483fd3764637abdf95de2893b437d0Richard Smith expected-warning {{not an integral constant expression}} \ 3014cd9b8f7fb2cebf614e6e2bc766fad27ffd2e9deRichard Smith expected-note {{dynamic_cast is not allowed in a constant expression}} 302c216a01c96d83bd9a90e214af64913e93d39aaccRichard Smith int b : reinterpret_cast<S*>(sptr) == reinterpret_cast<S*>(sptr); // \ 303244ee7b89a483fd3764637abdf95de2893b437d0Richard Smith expected-warning {{not an integral constant expression}} \ 3044cd9b8f7fb2cebf614e6e2bc766fad27ffd2e9deRichard Smith expected-note {{reinterpret_cast is not allowed in a constant expression}} 305c216a01c96d83bd9a90e214af64913e93d39aaccRichard Smith int c : (S*)(long)(sptr) == (S*)(long)(sptr); // \ 306244ee7b89a483fd3764637abdf95de2893b437d0Richard Smith expected-warning {{not an integral constant expression}} \ 307bebf5b1bcfbf591dd3cd80c4aebd6486bb34f41cRichard Smith expected-note {{cast that performs the conversions of a reinterpret_cast is not allowed in a constant expression}} 308c216a01c96d83bd9a90e214af64913e93d39aaccRichard Smith int d : (S*)(42) == (S*)(42); // \ 309244ee7b89a483fd3764637abdf95de2893b437d0Richard Smith expected-warning {{not an integral constant expression}} \ 310bebf5b1bcfbf591dd3cd80c4aebd6486bb34f41cRichard Smith expected-note {{cast that performs the conversions of a reinterpret_cast is not allowed in a constant expression}} 311c216a01c96d83bd9a90e214af64913e93d39aaccRichard Smith int e : (Str*)(sptr) == (Str*)(sptr); // \ 312244ee7b89a483fd3764637abdf95de2893b437d0Richard Smith expected-warning {{not an integral constant expression}} \ 313bebf5b1bcfbf591dd3cd80c4aebd6486bb34f41cRichard Smith expected-note {{cast that performs the conversions of a reinterpret_cast is not allowed in a constant expression}} 3142fd5983e0da447291a651a347c206aee37a1de5fRichard Smith int f : &(U&)(*sptr) == &(U&)(*sptr); // \ 315244ee7b89a483fd3764637abdf95de2893b437d0Richard Smith expected-warning {{not an integral constant expression}} \ 316bebf5b1bcfbf591dd3cd80c4aebd6486bb34f41cRichard Smith expected-note {{cast that performs the conversions of a reinterpret_cast is not allowed in a constant expression}} 317c216a01c96d83bd9a90e214af64913e93d39aaccRichard Smith int g : (S*)(void*)(sptr) == sptr; // \ 318244ee7b89a483fd3764637abdf95de2893b437d0Richard Smith expected-warning {{not an integral constant expression}} \ 3194cd9b8f7fb2cebf614e6e2bc766fad27ffd2e9deRichard Smith expected-note {{cast from 'void *' is not allowed in a constant expression}} 320c216a01c96d83bd9a90e214af64913e93d39aaccRichard Smith}; 321c216a01c96d83bd9a90e214af64913e93d39aaccRichard Smith 32259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithextern char externalvar[]; 3239eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithconstexpr bool constaddress = (void *)externalvar == (void *)0x4000UL; // expected-error {{must be initialized by a constant expression}} 32459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr bool litaddress = "foo" == "foo"; // expected-error {{must be initialized by a constant expression}} expected-warning {{unspecified}} 3259eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(0 != "foo", ""); 32659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 32759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 32859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 32959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithnamespace MaterializeTemporary { 33059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 33159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int f(const int &r) { return r; } 33259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int n = f(1); 33359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 33459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr bool same(const int &a, const int &b) { return &a == &b; } 33559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr bool sameTemporary(const int &n) { return same(n, n); } 33659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 3379eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(n, ""); 3389eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(!same(4, 4), ""); 3399eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(same(n, n), ""); 3409eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(sameTemporary(9), ""); 34159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 34259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 34359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 34459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int strcmp_ce(const char *p, const char *q) { 34559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith return (!*p || *p != *q) ? *p - *q : strcmp_ce(p+1, q+1); 34659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 34759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 34859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithnamespace StringLiteral { 34959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 3501d238ea926bbdd04356ce475934fcd4cac654c4bRichard Smithtemplate<typename Char> 3511d238ea926bbdd04356ce475934fcd4cac654c4bRichard Smithconstexpr int MangleChars(const Char *p) { 35259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith return *p + 3 * (*p ? MangleChars(p+1) : 0); 35359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 35459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 3559eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(MangleChars("constexpr!") == 1768383, ""); 356ec789163a42a7be654ac34aadb750b508954d53cRichard Smithstatic_assert(MangleChars(u8"constexpr!") == 1768383, ""); 357ec789163a42a7be654ac34aadb750b508954d53cRichard Smithstatic_assert(MangleChars(L"constexpr!") == 1768383, ""); 3589eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(MangleChars(u"constexpr!") == 1768383, ""); 3599eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(MangleChars(U"constexpr!") == 1768383, ""); 36059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 36159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr char c0 = "nought index"[0]; 36259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr char c1 = "nice index"[10]; 3637098cbd601ad915aed22d4b5850da99359f25bf3Richard Smithconstexpr char c2 = "nasty index"[12]; // expected-error {{must be initialized by a constant expression}} expected-warning {{is past the end}} expected-note {{read of dereferenced one-past-the-end pointer}} 364b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smithconstexpr char c3 = "negative index"[-1]; // expected-error {{must be initialized by a constant expression}} expected-warning {{is before the beginning}} expected-note {{cannot refer to element -1 of array of 15 elements}} 365bebf5b1bcfbf591dd3cd80c4aebd6486bb34f41cRichard Smithconstexpr char c4 = ((char*)(int*)"no reinterpret_casts allowed")[14]; // expected-error {{must be initialized by a constant expression}} expected-note {{cast that performs the conversions of a reinterpret_cast}} 36659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 36759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr const char *p = "test" + 2; 3689eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(*p == 's', ""); 36959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 37059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr const char *max_iter(const char *a, const char *b) { 37159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith return *a < *b ? b : a; 37259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 37359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr const char *max_element(const char *a, const char *b) { 37459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith return (a+1 >= b) ? a : max_iter(a, max_element(a+1, b)); 37559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 37659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 37759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr char str[] = "the quick brown fox jumped over the lazy dog"; 37859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr const char *max = max_element(begin(str), end(str)); 3799eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(*max == 'z', ""); 3809eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(max == str + 38, ""); 38159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 3829eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(strcmp_ce("hello world", "hello world") == 0, ""); 3839eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(strcmp_ce("hello world", "hello clang") > 0, ""); 3849eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(strcmp_ce("constexpr", "test") < 0, ""); 3859eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(strcmp_ce("", " ") < 0, ""); 38659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 3877098cbd601ad915aed22d4b5850da99359f25bf3Richard Smithstruct S { 3887098cbd601ad915aed22d4b5850da99359f25bf3Richard Smith int n : "foo"[4]; // expected-error {{constant expression}} expected-note {{read of dereferenced one-past-the-end pointer is not allowed in a constant expression}} 3897098cbd601ad915aed22d4b5850da99359f25bf3Richard Smith}; 3907098cbd601ad915aed22d4b5850da99359f25bf3Richard Smith 391974c5f93d0ce4f0699a6f0a4402f6b367da495e3Richard Smithstruct T { 392974c5f93d0ce4f0699a6f0a4402f6b367da495e3Richard Smith char c[6]; 393974c5f93d0ce4f0699a6f0a4402f6b367da495e3Richard Smith constexpr T() : c{"foo"} {} 394974c5f93d0ce4f0699a6f0a4402f6b367da495e3Richard Smith}; 395974c5f93d0ce4f0699a6f0a4402f6b367da495e3Richard Smithconstexpr T t; 396974c5f93d0ce4f0699a6f0a4402f6b367da495e3Richard Smith 397974c5f93d0ce4f0699a6f0a4402f6b367da495e3Richard Smithstatic_assert(t.c[0] == 'f', ""); 398974c5f93d0ce4f0699a6f0a4402f6b367da495e3Richard Smithstatic_assert(t.c[1] == 'o', ""); 399974c5f93d0ce4f0699a6f0a4402f6b367da495e3Richard Smithstatic_assert(t.c[2] == 'o', ""); 400974c5f93d0ce4f0699a6f0a4402f6b367da495e3Richard Smithstatic_assert(t.c[3] == 0, ""); 401974c5f93d0ce4f0699a6f0a4402f6b367da495e3Richard Smithstatic_assert(t.c[4] == 0, ""); 402974c5f93d0ce4f0699a6f0a4402f6b367da495e3Richard Smithstatic_assert(t.c[5] == 0, ""); 403974c5f93d0ce4f0699a6f0a4402f6b367da495e3Richard Smithstatic_assert(t.c[6] == 0, ""); // expected-error {{constant expression}} expected-note {{one-past-the-end}} 404974c5f93d0ce4f0699a6f0a4402f6b367da495e3Richard Smith 405ec789163a42a7be654ac34aadb750b508954d53cRichard Smithstruct U { 406ec789163a42a7be654ac34aadb750b508954d53cRichard Smith wchar_t chars[6]; 407ec789163a42a7be654ac34aadb750b508954d53cRichard Smith int n; 408ec789163a42a7be654ac34aadb750b508954d53cRichard Smith} constexpr u = { { L"test" }, 0 }; 409ec789163a42a7be654ac34aadb750b508954d53cRichard Smithstatic_assert(u.chars[2] == L's', ""); 410ec789163a42a7be654ac34aadb750b508954d53cRichard Smith 411f3908f2ae111b1b12ade2524dda71c669ed6f121Richard Smithstruct V { 412f3908f2ae111b1b12ade2524dda71c669ed6f121Richard Smith char c[4]; 413f3908f2ae111b1b12ade2524dda71c669ed6f121Richard Smith constexpr V() : c("hi!") {} 414f3908f2ae111b1b12ade2524dda71c669ed6f121Richard Smith}; 415f3908f2ae111b1b12ade2524dda71c669ed6f121Richard Smithstatic_assert(V().c[1] == "i"[0], ""); 416f3908f2ae111b1b12ade2524dda71c669ed6f121Richard Smith 41730ae1ed71dc99a396b7ddba9cabe9846a0c4449dRichard Smithnamespace Parens { 41830ae1ed71dc99a396b7ddba9cabe9846a0c4449dRichard Smith constexpr unsigned char a[] = ("foo"), b[] = {"foo"}, c[] = {("foo")}, 41930ae1ed71dc99a396b7ddba9cabe9846a0c4449dRichard Smith d[4] = ("foo"), e[5] = {"foo"}, f[6] = {("foo")}; 42030ae1ed71dc99a396b7ddba9cabe9846a0c4449dRichard Smith static_assert(a[0] == 'f', ""); 42130ae1ed71dc99a396b7ddba9cabe9846a0c4449dRichard Smith static_assert(b[1] == 'o', ""); 42230ae1ed71dc99a396b7ddba9cabe9846a0c4449dRichard Smith static_assert(c[2] == 'o', ""); 42330ae1ed71dc99a396b7ddba9cabe9846a0c4449dRichard Smith static_assert(d[0] == 'f', ""); 42430ae1ed71dc99a396b7ddba9cabe9846a0c4449dRichard Smith static_assert(e[1] == 'o', ""); 42530ae1ed71dc99a396b7ddba9cabe9846a0c4449dRichard Smith static_assert(f[2] == 'o', ""); 42630ae1ed71dc99a396b7ddba9cabe9846a0c4449dRichard Smith static_assert(f[5] == 0, ""); 42730ae1ed71dc99a396b7ddba9cabe9846a0c4449dRichard Smith static_assert(f[6] == 0, ""); // expected-error {{constant expression}} expected-note {{one-past-the-end}} 42830ae1ed71dc99a396b7ddba9cabe9846a0c4449dRichard Smith} 42930ae1ed71dc99a396b7ddba9cabe9846a0c4449dRichard Smith 43059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 43159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 43259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithnamespace Array { 43359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 4341d238ea926bbdd04356ce475934fcd4cac654c4bRichard Smithtemplate<typename Iter> 4351d238ea926bbdd04356ce475934fcd4cac654c4bRichard Smithconstexpr auto Sum(Iter begin, Iter end) -> decltype(+*begin) { 43659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith return begin == end ? 0 : *begin + Sum(begin+1, end); 43759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 43859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 43959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int xs[] = { 1, 2, 3, 4, 5 }; 44059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int ys[] = { 5, 4, 3, 2, 1 }; 44159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int sum_xs = Sum(begin(xs), end(xs)); 4429eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(sum_xs == 15, ""); 44359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 44459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int ZipFoldR(int (*F)(int x, int y, int c), int n, 44559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith const int *xs, const int *ys, int c) { 446daaefc5381f9aafbb1cb6f88fb5ac6aaf34d65bfRichard Smith return n ? F( 4477098cbd601ad915aed22d4b5850da99359f25bf3Richard Smith *xs, // expected-note {{read of dereferenced one-past-the-end pointer}} 44808d6e032a2a0a8656d12b3b7b93942987bb12eb7Richard Smith *ys, 44908d6e032a2a0a8656d12b3b7b93942987bb12eb7Richard Smith ZipFoldR(F, n-1, xs+1, ys+1, c)) // \ 45008d6e032a2a0a8656d12b3b7b93942987bb12eb7Richard Smith expected-note {{in call to 'ZipFoldR(&SubMul, 2, &xs[4], &ys[4], 1)'}} \ 45108d6e032a2a0a8656d12b3b7b93942987bb12eb7Richard Smith expected-note {{in call to 'ZipFoldR(&SubMul, 1, &xs[5], &ys[5], 1)'}} 45208d6e032a2a0a8656d12b3b7b93942987bb12eb7Richard Smith : c; 45359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 45459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int MulAdd(int x, int y, int c) { return x * y + c; } 45559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int InnerProduct = ZipFoldR(MulAdd, 5, xs, ys, 0); 4569eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(InnerProduct == 35, ""); 45759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 45859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int SubMul(int x, int y, int c) { return (x - y) * c; } 45959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int DiffProd = ZipFoldR(SubMul, 2, xs+3, ys+3, 1); 4609eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(DiffProd == 8, ""); 46108d6e032a2a0a8656d12b3b7b93942987bb12eb7Richard Smithstatic_assert(ZipFoldR(SubMul, 3, xs+3, ys+3, 1), ""); // \ 46208d6e032a2a0a8656d12b3b7b93942987bb12eb7Richard Smith expected-error {{constant expression}} \ 46308d6e032a2a0a8656d12b3b7b93942987bb12eb7Richard Smith expected-note {{in call to 'ZipFoldR(&SubMul, 3, &xs[3], &ys[3], 1)'}} 46459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 46559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr const int *p = xs + 3; 46659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int xs4 = p[1]; // ok 4677098cbd601ad915aed22d4b5850da99359f25bf3Richard Smithconstexpr int xs5 = p[2]; // expected-error {{constant expression}} expected-note {{read of dereferenced one-past-the-end pointer}} 468b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smithconstexpr int xs6 = p[3]; // expected-error {{constant expression}} expected-note {{cannot refer to element 6}} 46959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int xs0 = p[-3]; // ok 470b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smithconstexpr int xs_1 = p[-4]; // expected-error {{constant expression}} expected-note {{cannot refer to element -1}} 47159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 47259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int zs[2][2][2][2] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 }; 4739eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(zs[0][0][0][0] == 1, ""); 4749eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(zs[1][1][1][1] == 16, ""); 4757098cbd601ad915aed22d4b5850da99359f25bf3Richard Smithstatic_assert(zs[0][0][0][2] == 3, ""); // expected-error {{constant expression}} expected-note {{read of dereferenced one-past-the-end pointer}} 4769eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert((&zs[0][0][0][2])[-1] == 2, ""); 4779eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(**(**(zs + 1) + 1) == 11, ""); 478b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smithstatic_assert(*(&(&(*(*&(&zs[2] - 1)[0] + 2 - 2))[2])[-1][-1] + 1) == 11, ""); // expected-error {{constant expression}} expected-note {{cannot refer to element -1 of array of 2 elements in a constant expression}} 479b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smithstatic_assert(*(&(&(*(*&(&zs[2] - 1)[0] + 2 - 2))[2])[-1][2] - 2) == 11, ""); 480b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smithconstexpr int err_zs_1_2_0_0 = zs[1][2][0][0]; // expected-error {{constant expression}} expected-note {{cannot access array element of pointer past the end}} 48159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 48208d6e032a2a0a8656d12b3b7b93942987bb12eb7Richard Smithconstexpr int fail(const int &p) { 483b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smith return (&p)[64]; // expected-note {{cannot refer to element 64 of array of 2 elements}} 48408d6e032a2a0a8656d12b3b7b93942987bb12eb7Richard Smith} 485b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smithstatic_assert(fail(*(&(&(*(*&(&zs[2] - 1)[0] + 2 - 2))[2])[-1][2] - 2)) == 11, ""); // \ 48608d6e032a2a0a8656d12b3b7b93942987bb12eb7Richard Smithexpected-error {{static_assert expression is not an integral constant expression}} \ 48708d6e032a2a0a8656d12b3b7b93942987bb12eb7Richard Smithexpected-note {{in call to 'fail(zs[1][0][1][0])'}} 48808d6e032a2a0a8656d12b3b7b93942987bb12eb7Richard Smith 489d7c56e1114bfe7d461786903bb720d2c6efc05a1Richard Smithconstexpr int arr[40] = { 1, 2, 3, [8] = 4 }; // expected-warning {{C99 feature}} 49059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int SumNonzero(const int *p) { 49159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith return *p + (*p ? SumNonzero(p+1) : 0); 49259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 49359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int CountZero(const int *p, const int *q) { 49459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith return p == q ? 0 : (*p == 0) + CountZero(p+1, q); 49559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 4969eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(SumNonzero(arr) == 6, ""); 4979eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(CountZero(arr, arr + 40) == 36, ""); 49859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 499e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithstruct ArrayElem { 500e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr ArrayElem() : n(0) {} 501e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith int n; 502840462670ba7a6bc26265a2306b35f2f0f01f51cRichard Smith constexpr int f() const { return n; } 503e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith}; 504e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithstruct ArrayRVal { 505e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr ArrayRVal() {} 506e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith ArrayElem elems[10]; 507e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith}; 5089eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(ArrayRVal().elems[3].f() == 0, ""); 509e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 510de31aa7f0ef71f5c162372e319cbc03c0924f074Richard Smithconstexpr int selfref[2][2][2] = { 511de31aa7f0ef71f5c162372e319cbc03c0924f074Richard Smith selfref[1][1][1] + 1, selfref[0][0][0] + 1, 512de31aa7f0ef71f5c162372e319cbc03c0924f074Richard Smith selfref[1][0][1] + 1, selfref[0][1][0] + 1, 513de31aa7f0ef71f5c162372e319cbc03c0924f074Richard Smith selfref[1][0][0] + 1, selfref[0][1][1] + 1 }; 514de31aa7f0ef71f5c162372e319cbc03c0924f074Richard Smithstatic_assert(selfref[0][0][0] == 1, ""); 515de31aa7f0ef71f5c162372e319cbc03c0924f074Richard Smithstatic_assert(selfref[0][0][1] == 2, ""); 516de31aa7f0ef71f5c162372e319cbc03c0924f074Richard Smithstatic_assert(selfref[0][1][0] == 1, ""); 517de31aa7f0ef71f5c162372e319cbc03c0924f074Richard Smithstatic_assert(selfref[0][1][1] == 2, ""); 518de31aa7f0ef71f5c162372e319cbc03c0924f074Richard Smithstatic_assert(selfref[1][0][0] == 1, ""); 519de31aa7f0ef71f5c162372e319cbc03c0924f074Richard Smithstatic_assert(selfref[1][0][1] == 3, ""); 520de31aa7f0ef71f5c162372e319cbc03c0924f074Richard Smithstatic_assert(selfref[1][1][0] == 0, ""); 521de31aa7f0ef71f5c162372e319cbc03c0924f074Richard Smithstatic_assert(selfref[1][1][1] == 0, ""); 522de31aa7f0ef71f5c162372e319cbc03c0924f074Richard Smith 523a4334dffde250c22c339a974a7131914fe723180Richard Smithstruct TrivialDefCtor { int n; }; 524a4334dffde250c22c339a974a7131914fe723180Richard Smithtypedef TrivialDefCtor TDCArray[2][2]; 525a4334dffde250c22c339a974a7131914fe723180Richard Smithstatic_assert(TDCArray{}[1][1].n == 0, ""); 526a4334dffde250c22c339a974a7131914fe723180Richard Smith 527a4334dffde250c22c339a974a7131914fe723180Richard Smithstruct NonAggregateTDC : TrivialDefCtor {}; 528a4334dffde250c22c339a974a7131914fe723180Richard Smithtypedef NonAggregateTDC NATDCArray[2][2]; 529a4334dffde250c22c339a974a7131914fe723180Richard Smithstatic_assert(NATDCArray{}[1][1].n == 0, ""); 530a4334dffde250c22c339a974a7131914fe723180Richard Smith 53159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 53259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 53359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithnamespace DependentValues { 53459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 53559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithstruct I { int n; typedef I V[10]; }; 53659efe266b804330f4c1f3a1b0ff783e67dd90378Richard SmithI::V x, y; 5379568f0c13a84695c5cc064e7c32412f84604cb1eRichard Smithint g(); 5381432a43e3076eec84967305bd85bace3a6e9102bRichard Smithtemplate<bool B, typename T> struct S : T { 53959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith int k; 54059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith void f() { 54159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith I::V &cells = B ? x : y; 54259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith I &i = cells[k]; 54359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith switch (i.n) {} 5441432a43e3076eec84967305bd85bace3a6e9102bRichard Smith 5459568f0c13a84695c5cc064e7c32412f84604cb1eRichard Smith // FIXME: We should be able to diagnose this. 5469568f0c13a84695c5cc064e7c32412f84604cb1eRichard Smith constexpr int n = g(); 5471432a43e3076eec84967305bd85bace3a6e9102bRichard Smith 5481432a43e3076eec84967305bd85bace3a6e9102bRichard Smith constexpr int m = this->g(); // ok, could be constexpr 54959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith } 55059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith}; 55159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 55259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 55359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 55459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithnamespace Class { 55559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 55659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithstruct A { constexpr A(int a, int b) : k(a + b) {} int k; }; 55759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int fn(const A &a) { return a.k; } 5589eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(fn(A(4,5)) == 9, ""); 55959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 56059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithstruct B { int n; int m; } constexpr b = { 0, b.n }; // expected-warning {{uninitialized}} 56159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithstruct C { 56259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr C(C *this_) : m(42), n(this_->m) {} // ok 56359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith int m, n; 56459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith}; 56559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithstruct D { 56659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith C c; 56759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr D() : c(&c) {} 56859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith}; 5699eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(D().c.n == 42, ""); 57059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 5716180245e9f63d2927b185ec251fb75aba30f1cacRichard Smithstruct E { 57283587db1bda97f45d2b5a4189e584e2a18be511aRichard Smith constexpr E() : p(&p) {} 57359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith void *p; 57459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith}; 57583587db1bda97f45d2b5a4189e584e2a18be511aRichard Smithconstexpr const E &e1 = E(); // expected-error {{constant expression}} expected-note {{reference to temporary is not a constant expression}} expected-note {{temporary created here}} 57659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith// This is a constant expression if we elide the copy constructor call, and 57759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith// is not a constant expression if we don't! But we do, so it is. 5786180245e9f63d2927b185ec251fb75aba30f1cacRichard Smithconstexpr E e2 = E(); 5796180245e9f63d2927b185ec251fb75aba30f1cacRichard Smithstatic_assert(e2.p == &e2.p, ""); 580099e7f647ccda915513f2b2ec53352dc756082d3Richard Smithconstexpr E e3; 5819eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(e3.p == &e3.p, ""); 58259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 58359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithextern const class F f; 58459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithstruct F { 58559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr F() : p(&f.p) {} 58659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith const void *p; 58759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith}; 588099e7f647ccda915513f2b2ec53352dc756082d3Richard Smithconstexpr F f; 58959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 59059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithstruct G { 59159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith struct T { 59259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr T(T *p) : u1(), u2(p) {} 59359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith union U1 { 59459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr U1() {} 59559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith int a, b = 42; 59659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith } u1; 59759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith union U2 { 59859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr U2(T *p) : c(p->u1.b) {} 59959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith int c, d; 60059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith } u2; 60159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith } t; 60259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr G() : t(&t) {} 60359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} constexpr g; 60459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 6057098cbd601ad915aed22d4b5850da99359f25bf3Richard Smithstatic_assert(g.t.u1.a == 42, ""); // expected-error {{constant expression}} expected-note {{read of member 'a' of union with active member 'b'}} 6069eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(g.t.u1.b == 42, ""); 6079eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(g.t.u2.c == 42, ""); 6087098cbd601ad915aed22d4b5850da99359f25bf3Richard Smithstatic_assert(g.t.u2.d == 42, ""); // expected-error {{constant expression}} expected-note {{read of member 'd' of union with active member 'c'}} 60959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 61059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithstruct S { 61159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith int a, b; 61259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith const S *p; 61359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith double d; 61459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith const char *q; 61559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 61659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr S(int n, const S *p) : a(5), b(n), p(p), d(n), q("hello") {} 61759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith}; 61859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 61959efe266b804330f4c1f3a1b0ff783e67dd90378Richard SmithS global(43, &global); 62059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 6219eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(S(15, &global).b == 15, ""); 62259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 62359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr bool CheckS(const S &s) { 62459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith return s.a == 5 && s.b == 27 && s.p == &global && s.d == 27. && s.q[3] == 'l'; 62559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 6269eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(CheckS(S(27, &global)), ""); 62759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 62859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithstruct Arr { 62959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith char arr[3]; 63059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr Arr() : arr{'x', 'y', 'z'} {} 63159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith}; 63259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int hash(Arr &&a) { 63359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith return a.arr[0] + a.arr[1] * 0x100 + a.arr[2] * 0x10000; 63459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 63559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int k = hash(Arr()); 6369eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(k == 0x007a7978, ""); 63759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 63859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 63959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithstruct AggregateInit { 64059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith const char &c; 64159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith int n; 64259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith double d; 64359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith int arr[5]; 64459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith void *p; 64559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith}; 64659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 64759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr AggregateInit agg1 = { "hello"[0] }; 64859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 6499eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(strcmp_ce(&agg1.c, "hello") == 0, ""); 6509eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(agg1.n == 0, ""); 6519eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(agg1.d == 0.0, ""); 652b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smithstatic_assert(agg1.arr[-1] == 0, ""); // expected-error {{constant expression}} expected-note {{cannot refer to element -1}} 6539eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(agg1.arr[0] == 0, ""); 6549eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(agg1.arr[4] == 0, ""); 6557098cbd601ad915aed22d4b5850da99359f25bf3Richard Smithstatic_assert(agg1.arr[5] == 0, ""); // expected-error {{constant expression}} expected-note {{read of dereferenced one-past-the-end}} 6569eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(agg1.p == nullptr, ""); 65759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 658fe587201feaebc69e6d18858bea85c77926b6ecfRichard Smithstatic constexpr const unsigned char uc[] = { "foo" }; 659fe587201feaebc69e6d18858bea85c77926b6ecfRichard Smithstatic_assert(uc[0] == 'f', ""); 660fe587201feaebc69e6d18858bea85c77926b6ecfRichard Smithstatic_assert(uc[3] == 0, ""); 661fe587201feaebc69e6d18858bea85c77926b6ecfRichard Smith 66259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithnamespace SimpleDerivedClass { 66359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 66459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithstruct B { 66559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr B(int n) : a(n) {} 66659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith int a; 66759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith}; 66859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithstruct D : B { 66959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr D(int n) : B(n) {} 67059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith}; 67159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr D d(3); 6729eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(d.a == 3, ""); 67359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 67459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 67559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 676e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithstruct Bottom { constexpr Bottom() {} }; 677e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithstruct Base : Bottom { 67859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr Base(int a = 42, const char *b = "test") : a(a), b(b) {} 67959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith int a; 68059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith const char *b; 68159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith}; 682e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithstruct Base2 : Bottom { 68359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr Base2(const int &r) : r(r) {} 68459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith int q = 123; 685099e7f647ccda915513f2b2ec53352dc756082d3Richard Smith const int &r; 68659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith}; 68759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithstruct Derived : Base, Base2 { 68859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr Derived() : Base(76), Base2(a) {} 68959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith int c = r + b[1]; 69059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith}; 69159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 69259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr bool operator==(const Base &a, const Base &b) { 69359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith return a.a == b.a && strcmp_ce(a.b, b.b) == 0; 69459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 69559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 69659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr Base base; 69759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr Base base2(76); 69859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr Derived derived; 6999eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(derived.a == 76, ""); 7009eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(derived.b[2] == 's', ""); 7019eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(derived.c == 76 + 'e', ""); 7029eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(derived.q == 123, ""); 7039eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(derived.r == 76, ""); 704099e7f647ccda915513f2b2ec53352dc756082d3Richard Smithstatic_assert(&derived.r == &derived.a, ""); 70559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 7069eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(!(derived == base), ""); 7079eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(derived == base2, ""); 70859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 709e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithconstexpr Bottom &bot1 = (Base&)derived; 710e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithconstexpr Bottom &bot2 = (Base2&)derived; 7119eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(&bot1 != &bot2, ""); 712e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 713e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithconstexpr Bottom *pb1 = (Base*)&derived; 714e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithconstexpr Bottom *pb2 = (Base2*)&derived; 715f15fda02e9c8c82b4a716618f4010b9af8bff796Richard Smithstatic_assert(&pb1 != &pb2, ""); 7169eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(pb1 == &bot1, ""); 7179eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(pb2 == &bot2, ""); 718e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 719b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smithconstexpr Base2 &fail = (Base2&)bot1; // expected-error {{constant expression}} expected-note {{cannot cast object of dynamic type 'const Class::Derived' to type 'Class::Base2'}} 720b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smithconstexpr Base &fail2 = (Base&)*pb2; // expected-error {{constant expression}} expected-note {{cannot cast object of dynamic type 'const Class::Derived' to type 'Class::Base'}} 721e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithconstexpr Base2 &ok2 = (Base2&)bot2; 7229eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(&ok2 == &derived, ""); 723e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 724b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smithconstexpr Base2 *pfail = (Base2*)pb1; // expected-error {{constant expression}} expected-note {{cannot cast object of dynamic type 'const Class::Derived' to type 'Class::Base2'}} 725b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smithconstexpr Base *pfail2 = (Base*)&bot2; // expected-error {{constant expression}} expected-note {{cannot cast object of dynamic type 'const Class::Derived' to type 'Class::Base'}} 726e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithconstexpr Base2 *pok2 = (Base2*)pb2; 7279eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(pok2 == &derived, ""); 7289eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(&ok2 == pok2, ""); 7299eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert((Base2*)(Derived*)(Base*)pb1 == pok2, ""); 7309eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert((Derived*)(Base*)pb1 == (Derived*)pok2, ""); 731e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 73250800fc551ac6b8a95cca662223e7f061bbd169aDavid Blaikieconstexpr Base *nullB = 42 - 6 * 7; // expected-warning {{expression which evaluates to zero treated as a null pointer constant of type 'Class::Base *const'}} 7339eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert((Bottom*)nullB == 0, ""); 7349eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert((Derived*)nullB == 0, ""); 7359eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert((void*)(Bottom*)nullB == (void*)(Derived*)nullB, ""); 73650800fc551ac6b8a95cca662223e7f061bbd169aDavid BlaikieBase * nullB2 = '\0'; // expected-warning {{expression which evaluates to zero treated as a null pointer constant of type 'Class::Base *'}} 73750800fc551ac6b8a95cca662223e7f061bbd169aDavid BlaikieBase * nullB3 = (0); 73850800fc551ac6b8a95cca662223e7f061bbd169aDavid Blaikie// We suppress the warning in unevaluated contexts to workaround some gtest 73950800fc551ac6b8a95cca662223e7f061bbd169aDavid Blaikie// behavior. Once this becomes an error this isn't a problem anymore. 74050800fc551ac6b8a95cca662223e7f061bbd169aDavid Blaikiestatic_assert(nullB == (1 - 1), ""); 74150800fc551ac6b8a95cca662223e7f061bbd169aDavid Blaikie 742e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 7437d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smithnamespace ConversionOperators { 7447d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smith 7457d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smithstruct T { 7467d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smith constexpr T(int n) : k(5*n - 3) {} 747840462670ba7a6bc26265a2306b35f2f0f01f51cRichard Smith constexpr operator int() const { return k; } 7487d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smith int k; 7497d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smith}; 7507d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smith 7517d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smithstruct S { 7527d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smith constexpr S(int n) : k(2*n + 1) {} 753840462670ba7a6bc26265a2306b35f2f0f01f51cRichard Smith constexpr operator int() const { return k; } 754840462670ba7a6bc26265a2306b35f2f0f01f51cRichard Smith constexpr operator T() const { return T(k); } 7557d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smith int k; 7567d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smith}; 7577d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smith 7587d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smithconstexpr bool check(T a, T b) { return a == b.k; } 7597d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smith 7607d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smithstatic_assert(S(5) == 11, ""); 7617d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smithstatic_assert(check(S(5), 11), ""); 7627d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smith 763e925322569cb4aad26cc62036a13e2d3daed862dRichard Smithnamespace PR14171 { 764e925322569cb4aad26cc62036a13e2d3daed862dRichard Smith 765e925322569cb4aad26cc62036a13e2d3daed862dRichard Smithstruct X { 766840462670ba7a6bc26265a2306b35f2f0f01f51cRichard Smith constexpr (operator int)() const { return 0; } 767e925322569cb4aad26cc62036a13e2d3daed862dRichard Smith}; 768e925322569cb4aad26cc62036a13e2d3daed862dRichard Smithstatic_assert(X() == 0, ""); 769e925322569cb4aad26cc62036a13e2d3daed862dRichard Smith 770e925322569cb4aad26cc62036a13e2d3daed862dRichard Smith} 771e925322569cb4aad26cc62036a13e2d3daed862dRichard Smith 7727d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smith} 7737d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smith 774e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith} 775e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 776e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithnamespace Temporaries { 777e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 778e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithstruct S { 779e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr S() {} 780840462670ba7a6bc26265a2306b35f2f0f01f51cRichard Smith constexpr int f() const; 781e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith}; 782e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithstruct T : S { 783e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr T(int n) : S(), n(n) {} 784e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith int n; 785e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith}; 786840462670ba7a6bc26265a2306b35f2f0f01f51cRichard Smithconstexpr int S::f() const { 787e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith // 'this' must be the postfix-expression in a class member access expression, 788e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith // so we can't just use 789e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith // return static_cast<T*>(this)->n; 790e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith return this->*(int(S::*))&T::n; 791e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith} 792e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith// The T temporary is implicitly cast to an S subobject, but we can recover the 793e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith// T full-object via a base-to-derived cast, or a derived-to-base-casted member 794e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith// pointer. 7959eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(T(3).f() == 3, ""); 796e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 797e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithconstexpr int f(const S &s) { 798e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith return static_cast<const T&>(s).n; 799e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith} 800e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithconstexpr int n = f(T(5)); 8019eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(f(T(5)) == 5, ""); 802e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 803f2e4cd760a5836ee8941d1b9be6b2e2c2dde23e6Richard Smithconstexpr bool b(int n) { return &n; } 804f2e4cd760a5836ee8941d1b9be6b2e2c2dde23e6Richard Smithstatic_assert(b(0), ""); 805f2e4cd760a5836ee8941d1b9be6b2e2c2dde23e6Richard Smith 80659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 80759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 80859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithnamespace Union { 80959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 81059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithunion U { 81159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith int a; 81259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith int b; 81359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith}; 81459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 815d7c56e1114bfe7d461786903bb720d2c6efc05a1Richard Smithconstexpr U u[4] = { { .a = 0 }, { .b = 1 }, { .a = 2 }, { .b = 3 } }; // expected-warning 4{{C99 feature}} 8169eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(u[0].a == 0, ""); 8177098cbd601ad915aed22d4b5850da99359f25bf3Richard Smithstatic_assert(u[0].b, ""); // expected-error {{constant expression}} expected-note {{read of member 'b' of union with active member 'a'}} 8189eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(u[1].b == 1, ""); 8197098cbd601ad915aed22d4b5850da99359f25bf3Richard Smithstatic_assert((&u[1].b)[1] == 2, ""); // expected-error {{constant expression}} expected-note {{read of dereferenced one-past-the-end pointer}} 820b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smithstatic_assert(*(&(u[1].b) + 1 + 1) == 3, ""); // expected-error {{constant expression}} expected-note {{cannot refer to element 2 of non-array object}} 8219eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert((&(u[1]) + 1 + 1)->b == 3, ""); 82259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 823ec789163a42a7be654ac34aadb750b508954d53cRichard Smithconstexpr U v = {}; 824ec789163a42a7be654ac34aadb750b508954d53cRichard Smithstatic_assert(v.a == 0, ""); 825ec789163a42a7be654ac34aadb750b508954d53cRichard Smith 826ec789163a42a7be654ac34aadb750b508954d53cRichard Smithunion Empty {}; 827ec789163a42a7be654ac34aadb750b508954d53cRichard Smithconstexpr Empty e = {}; 828ec789163a42a7be654ac34aadb750b508954d53cRichard Smith 829610a60c0e68e34db5a5247d6102e58f37510fef8Richard Smith// Make sure we handle trivial copy constructors for unions. 830610a60c0e68e34db5a5247d6102e58f37510fef8Richard Smithconstexpr U x = {42}; 831610a60c0e68e34db5a5247d6102e58f37510fef8Richard Smithconstexpr U y = x; 832610a60c0e68e34db5a5247d6102e58f37510fef8Richard Smithstatic_assert(y.a == 42, ""); 833610a60c0e68e34db5a5247d6102e58f37510fef8Richard Smithstatic_assert(y.b == 42, ""); // expected-error {{constant expression}} expected-note {{'b' of union with active member 'a'}} 834610a60c0e68e34db5a5247d6102e58f37510fef8Richard Smith 83559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 83659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 837e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithnamespace MemberPointer { 838e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith struct A { 839e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr A(int n) : n(n) {} 840e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith int n; 841840462670ba7a6bc26265a2306b35f2f0f01f51cRichard Smith constexpr int f() const { return n + 3; } 842e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith }; 843e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr A a(7); 8449eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(A(5).*&A::n == 5, ""); 8459eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert((&a)->*&A::n == 7, ""); 8469eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert((A(8).*&A::f)() == 11, ""); 8479eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(((&a)->*&A::f)() == 10, ""); 848e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 849e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith struct B : A { 850e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr B(int n, int m) : A(n), m(m) {} 851e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith int m; 852840462670ba7a6bc26265a2306b35f2f0f01f51cRichard Smith constexpr int g() const { return n + m + 1; } 853e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith }; 854e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr B b(9, 13); 8559eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(B(4, 11).*&A::n == 4, ""); 8569eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(B(4, 11).*&B::m == 11, ""); 8579eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(B(4, 11).*(int(A::*))&B::m == 11, ""); 8589eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert((&b)->*&A::n == 9, ""); 8599eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert((&b)->*&B::m == 13, ""); 8609eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert((&b)->*(int(A::*))&B::m == 13, ""); 8619eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert((B(4, 11).*&A::f)() == 7, ""); 8629eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert((B(4, 11).*&B::g)() == 16, ""); 8639eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert((B(4, 11).*(int(A::*)()const)&B::g)() == 16, ""); 8649eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(((&b)->*&A::f)() == 12, ""); 8659eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(((&b)->*&B::g)() == 23, ""); 8669eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(((&b)->*(int(A::*)()const)&B::g)() == 23, ""); 867e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 868e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith struct S { 869e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr S(int m, int n, int (S::*pf)() const, int S::*pn) : 870e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith m(m), n(n), pf(pf), pn(pn) {} 871e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr S() : m(), n(), pf(&S::f), pn(&S::n) {} 872e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 873840462670ba7a6bc26265a2306b35f2f0f01f51cRichard Smith constexpr int f() const { return this->*pn; } 874e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith virtual int g() const; 875e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 876e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith int m, n; 877e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith int (S::*pf)() const; 878e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith int S::*pn; 879e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith }; 880e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 881e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr int S::*pm = &S::m; 882e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr int S::*pn = &S::n; 883e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr int (S::*pf)() const = &S::f; 884e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr int (S::*pg)() const = &S::g; 885e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 886e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr S s(2, 5, &S::f, &S::m); 887e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 8889eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert((s.*&S::f)() == 2, ""); 8899eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert((s.*s.pf)() == 2, ""); 890e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 891b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith static_assert(pf == &S::f, ""); 892b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith static_assert(pf == s.*&S::pf, ""); 893b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith static_assert(pm == &S::m, ""); 894b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith static_assert(pm != pn, ""); 895b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith static_assert(s.pn != pn, ""); 896b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith static_assert(s.pn == pm, ""); 897b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith static_assert(pg != nullptr, ""); 898b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith static_assert(pf != nullptr, ""); 899b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith static_assert((int S::*)nullptr == nullptr, ""); 900b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith static_assert(pg == pg, ""); // expected-error {{constant expression}} expected-note {{comparison of pointer to virtual member function 'g' has unspecified value}} 901b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith static_assert(pf != pg, ""); // expected-error {{constant expression}} expected-note {{comparison of pointer to virtual member function 'g' has unspecified value}} 902b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith 903e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith template<int n> struct T : T<n-1> {}; 904e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith template<> struct T<0> { int n; }; 905e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith template<> struct T<30> : T<29> { int m; }; 906e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 907e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith T<17> t17; 908e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith T<30> t30; 909e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 910e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr int (T<10>::*deepn) = &T<0>::n; 9119eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(&(t17.*deepn) == &t17.n, ""); 912b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith static_assert(deepn == &T<2>::n, ""); 913e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 914e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr int (T<15>::*deepm) = (int(T<10>::*))&T<30>::m; 915e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr int *pbad = &(t17.*deepm); // expected-error {{constant expression}} 9169eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(&(t30.*deepm) == &t30.m, ""); 917b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith static_assert(deepm == &T<50>::m, ""); 918b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith static_assert(deepm != deepn, ""); 919e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 920e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr T<5> *p17_5 = &t17; 921e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr T<13> *p17_13 = (T<13>*)p17_5; 922b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smith constexpr T<23> *p17_23 = (T<23>*)p17_13; // expected-error {{constant expression}} expected-note {{cannot cast object of dynamic type 'T<17>' to type 'T<23>'}} 9239eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(&(p17_5->*(int(T<3>::*))deepn) == &t17.n, ""); 9249eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(&(p17_13->*deepn) == &t17.n, ""); 925e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr int *pbad2 = &(p17_13->*(int(T<9>::*))deepm); // expected-error {{constant expression}} 926e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 927e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr T<5> *p30_5 = &t30; 928e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr T<23> *p30_23 = (T<23>*)p30_5; 929e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr T<13> *p30_13 = p30_23; 9309eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(&(p30_5->*(int(T<3>::*))deepn) == &t30.n, ""); 9319eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(&(p30_13->*deepn) == &t30.n, ""); 9329eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(&(p30_23->*deepn) == &t30.n, ""); 9339eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(&(p30_5->*(int(T<2>::*))deepm) == &t30.m, ""); 9349eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(&(((T<17>*)p30_13)->*deepm) == &t30.m, ""); 9359eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(&(p30_23->*deepm) == &t30.m, ""); 936b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith 937b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith struct Base { int n; }; 938b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith template<int N> struct Mid : Base {}; 939b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith struct Derived : Mid<0>, Mid<1> {}; 940b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith static_assert(&Mid<0>::n == &Mid<1>::n, ""); 941b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith static_assert((int Derived::*)(int Mid<0>::*)&Mid<0>::n != 942b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith (int Derived::*)(int Mid<1>::*)&Mid<1>::n, ""); 943b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith static_assert(&Mid<0>::n == (int Mid<0>::*)&Base::n, ""); 944e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith} 945e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 946e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithnamespace ArrayBaseDerived { 947e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 948e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith struct Base { 949e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr Base() {} 950e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith int n = 0; 951e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith }; 952e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith struct Derived : Base { 953e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr Derived() {} 954840462670ba7a6bc26265a2306b35f2f0f01f51cRichard Smith constexpr const int *f() const { return &n; } 955e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith }; 956e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 957e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr Derived a[10]; 958e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr Derived *pd3 = const_cast<Derived*>(&a[3]); 959e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr Base *pb3 = const_cast<Derived*>(&a[3]); 9609eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(pb3 == pd3, ""); 961e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 962e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith // pb3 does not point to an array element. 963e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr Base *pb4 = pb3 + 1; // ok, one-past-the-end pointer. 964b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smith constexpr int pb4n = pb4->n; // expected-error {{constant expression}} expected-note {{cannot access field of pointer past the end}} 965b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smith constexpr Base *err_pb5 = pb3 + 2; // expected-error {{constant expression}} expected-note {{cannot refer to element 2}} expected-note {{here}} 966b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smith constexpr int err_pb5n = err_pb5->n; // expected-error {{constant expression}} expected-note {{initializer of 'err_pb5' is not a constant expression}} 967b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smith constexpr Base *err_pb2 = pb3 - 1; // expected-error {{constant expression}} expected-note {{cannot refer to element -1}} expected-note {{here}} 968b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smith constexpr int err_pb2n = err_pb2->n; // expected-error {{constant expression}} expected-note {{initializer of 'err_pb2'}} 969e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr Base *pb3a = pb4 - 1; 970e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 971e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith // pb4 does not point to a Derived. 972b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smith constexpr Derived *err_pd4 = (Derived*)pb4; // expected-error {{constant expression}} expected-note {{cannot access derived class of pointer past the end}} 973e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr Derived *pd3a = (Derived*)pb3a; 974e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr int pd3n = pd3a->n; 975e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 976e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith // pd3a still points to the Derived array. 977e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr Derived *pd6 = pd3a + 3; 9789eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(pd6 == &a[6], ""); 979e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr Derived *pd9 = pd6 + 3; 980e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr Derived *pd10 = pd6 + 4; 981e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr int pd9n = pd9->n; // ok 982b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smith constexpr int err_pd10n = pd10->n; // expected-error {{constant expression}} expected-note {{cannot access base class of pointer past the end}} 983e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr int pd0n = pd10[-10].n; 984b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smith constexpr int err_pdminus1n = pd10[-11].n; // expected-error {{constant expression}} expected-note {{cannot refer to element -1 of}} 985e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 986e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr Base *pb9 = pd9; 987e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr const int *(Base::*pfb)() const = 988e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith static_cast<const int *(Base::*)() const>(&Derived::f); 9899eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert((pb9->*pfb)() == &a[9].n, ""); 990e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith} 991e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 99259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithnamespace Complex { 99359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 99459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithclass complex { 99559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith int re, im; 99659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithpublic: 99759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr complex(int re = 0, int im = 0) : re(re), im(im) {} 99859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr complex(const complex &o) : re(o.re), im(o.im) {} 99959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr complex operator-() const { return complex(-re, -im); } 100059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith friend constexpr complex operator+(const complex &l, const complex &r) { 100159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith return complex(l.re + r.re, l.im + r.im); 100259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith } 100359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith friend constexpr complex operator-(const complex &l, const complex &r) { 100459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith return l + -r; 100559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith } 100659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith friend constexpr complex operator*(const complex &l, const complex &r) { 100759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith return complex(l.re * r.re - l.im * r.im, l.re * r.im + l.im * r.re); 100859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith } 100959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith friend constexpr bool operator==(const complex &l, const complex &r) { 101059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith return l.re == r.re && l.im == r.im; 101159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith } 101259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr bool operator!=(const complex &r) const { 101359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith return re != r.re || im != r.im; 101459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith } 101559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr int real() const { return re; } 101659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr int imag() const { return im; } 101759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith}; 101859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 101959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr complex i = complex(0, 1); 102059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr complex k = (3 + 4*i) * (6 - 4*i); 10219eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(complex(1,0).real() == 1, ""); 10229eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(complex(1,0).imag() == 0, ""); 10239eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(((complex)1).imag() == 0, ""); 10249eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(k.real() == 34, ""); 10259eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(k.imag() == 12, ""); 10269eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(k - 34 == 12*i, ""); 10279eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert((complex)1 == complex(1), ""); 10289eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert((complex)1 != complex(0, 1), ""); 10299eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(complex(1) == complex(1), ""); 10309eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(complex(1) != complex(0, 1), ""); 103159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr complex makeComplex(int re, int im) { return complex(re, im); } 10329eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(makeComplex(1,0) == complex(1), ""); 10339eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(makeComplex(1,0) != complex(0, 1), ""); 103459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 103559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithclass complex_wrap : public complex { 103659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithpublic: 103759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr complex_wrap(int re, int im = 0) : complex(re, im) {} 103859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr complex_wrap(const complex_wrap &o) : complex(o) {} 103959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith}; 104059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 10419eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert((complex_wrap)1 == complex(1), ""); 10429eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert((complex)1 != complex_wrap(0, 1), ""); 10439eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(complex(1) == complex_wrap(1), ""); 10449eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(complex_wrap(1) != complex(0, 1), ""); 104559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr complex_wrap makeComplexWrap(int re, int im) { 104659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith return complex_wrap(re, im); 104759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 10489eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(makeComplexWrap(1,0) == complex(1), ""); 10499eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(makeComplexWrap(1,0) != complex(0, 1), ""); 105059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 105159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 1052f59ff8c777379bd54137853a58c58b72fb869152Eli Friedman 1053f59ff8c777379bd54137853a58c58b72fb869152Eli Friedmannamespace PR11595 { 1054840462670ba7a6bc26265a2306b35f2f0f01f51cRichard Smith struct A { constexpr bool operator==(int x) const { return true; } }; 1055af2c7a194592401394233b7cbcdd3cfd0a7a38ddRichard Smith struct B { B(); A& x; }; 1056af2c7a194592401394233b7cbcdd3cfd0a7a38ddRichard Smith static_assert(B().x == 3, ""); // expected-error {{constant expression}} expected-note {{non-literal type 'PR11595::B' cannot be used in a constant expression}} 1057af2c7a194592401394233b7cbcdd3cfd0a7a38ddRichard Smith 1058745f5147e065900267c85a5568785a1991d4838fRichard Smith constexpr bool f(int k) { // expected-error {{constexpr function never produces a constant expression}} 1059af2c7a194592401394233b7cbcdd3cfd0a7a38ddRichard Smith return B().x == k; // expected-note {{non-literal type 'PR11595::B' cannot be used in a constant expression}} 1060af2c7a194592401394233b7cbcdd3cfd0a7a38ddRichard Smith } 1061f59ff8c777379bd54137853a58c58b72fb869152Eli Friedman} 1062bc6abe93a5d6b1305411f8b6f54c2caa686ddc69Richard Smith 1063bc6abe93a5d6b1305411f8b6f54c2caa686ddc69Richard Smithnamespace ExprWithCleanups { 1064bc6abe93a5d6b1305411f8b6f54c2caa686ddc69Richard Smith struct A { A(); ~A(); int get(); }; 1065bc6abe93a5d6b1305411f8b6f54c2caa686ddc69Richard Smith constexpr int get(bool FromA) { return FromA ? A().get() : 1; } 1066bc6abe93a5d6b1305411f8b6f54c2caa686ddc69Richard Smith constexpr int n = get(false); 1067bc6abe93a5d6b1305411f8b6f54c2caa686ddc69Richard Smith} 10687098cbd601ad915aed22d4b5850da99359f25bf3Richard Smith 10697098cbd601ad915aed22d4b5850da99359f25bf3Richard Smithnamespace Volatile { 10707098cbd601ad915aed22d4b5850da99359f25bf3Richard Smith 10717098cbd601ad915aed22d4b5850da99359f25bf3Richard Smithvolatile constexpr int n1 = 0; // expected-note {{here}} 10727098cbd601ad915aed22d4b5850da99359f25bf3Richard Smithvolatile const int n2 = 0; // expected-note {{here}} 10737098cbd601ad915aed22d4b5850da99359f25bf3Richard Smithint n3 = 37; // expected-note {{declared here}} 10747098cbd601ad915aed22d4b5850da99359f25bf3Richard Smith 10759ec7197796a2730d54ae7f632553b5311b2ba3b5Richard Smithconstexpr int m1 = n1; // expected-error {{constant expression}} expected-note {{read of volatile-qualified type 'const volatile int'}} 10769ec7197796a2730d54ae7f632553b5311b2ba3b5Richard Smithconstexpr int m2 = n2; // expected-error {{constant expression}} expected-note {{read of volatile-qualified type 'const volatile int'}} 10779ec7197796a2730d54ae7f632553b5311b2ba3b5Richard Smithconstexpr int m1b = const_cast<const int&>(n1); // expected-error {{constant expression}} expected-note {{read of volatile object 'n1'}} 10789ec7197796a2730d54ae7f632553b5311b2ba3b5Richard Smithconstexpr int m2b = const_cast<const int&>(n2); // expected-error {{constant expression}} expected-note {{read of volatile object 'n2'}} 10797098cbd601ad915aed22d4b5850da99359f25bf3Richard Smith 10807098cbd601ad915aed22d4b5850da99359f25bf3Richard Smithstruct T { int n; }; 10817098cbd601ad915aed22d4b5850da99359f25bf3Richard Smithconst T t = { 42 }; // expected-note {{declared here}} 10827098cbd601ad915aed22d4b5850da99359f25bf3Richard Smith 10837098cbd601ad915aed22d4b5850da99359f25bf3Richard Smithconstexpr int f(volatile int &&r) { 10849ec7197796a2730d54ae7f632553b5311b2ba3b5Richard Smith return r; // expected-note {{read of volatile-qualified type 'volatile int'}} 10859ec7197796a2730d54ae7f632553b5311b2ba3b5Richard Smith} 10869ec7197796a2730d54ae7f632553b5311b2ba3b5Richard Smithconstexpr int g(volatile int &&r) { 10879ec7197796a2730d54ae7f632553b5311b2ba3b5Richard Smith return const_cast<int&>(r); // expected-note {{read of volatile temporary is not allowed in a constant expression}} 10887098cbd601ad915aed22d4b5850da99359f25bf3Richard Smith} 10897098cbd601ad915aed22d4b5850da99359f25bf3Richard Smithstruct S { 10909ec7197796a2730d54ae7f632553b5311b2ba3b5Richard Smith int j : f(0); // expected-error {{constant expression}} expected-note {{in call to 'f(0)'}} 10919ec7197796a2730d54ae7f632553b5311b2ba3b5Richard Smith int k : g(0); // expected-error {{constant expression}} expected-note {{temporary created here}} expected-note {{in call to 'g(0)'}} 10927098cbd601ad915aed22d4b5850da99359f25bf3Richard Smith int l : n3; // expected-error {{constant expression}} expected-note {{read of non-const variable}} 10937098cbd601ad915aed22d4b5850da99359f25bf3Richard Smith int m : t.n; // expected-error {{constant expression}} expected-note {{read of non-constexpr variable}} 10947098cbd601ad915aed22d4b5850da99359f25bf3Richard Smith}; 10957098cbd601ad915aed22d4b5850da99359f25bf3Richard Smith 10967098cbd601ad915aed22d4b5850da99359f25bf3Richard Smith} 1097dd4b350143c26c030a482f091908a2e077503411Richard Smith 1098dd4b350143c26c030a482f091908a2e077503411Richard Smithnamespace ExternConstexpr { 1099dd4b350143c26c030a482f091908a2e077503411Richard Smith extern constexpr int n = 0; 1100dd4b350143c26c030a482f091908a2e077503411Richard Smith extern constexpr int m; // expected-error {{constexpr variable declaration must be a definition}} 1101dd4b350143c26c030a482f091908a2e077503411Richard Smith void f() { 1102dd4b350143c26c030a482f091908a2e077503411Richard Smith extern constexpr int i; // expected-error {{constexpr variable declaration must be a definition}} 1103dd4b350143c26c030a482f091908a2e077503411Richard Smith constexpr int j = 0; 1104dd4b350143c26c030a482f091908a2e077503411Richard Smith constexpr int k; // expected-error {{default initialization of an object of const type}} 1105dd4b350143c26c030a482f091908a2e077503411Richard Smith } 1106dd4b350143c26c030a482f091908a2e077503411Richard Smith} 11077ead5c7b6fd48cf549e55b4db499c26ecf88ae75Eli Friedman 11087ead5c7b6fd48cf549e55b4db499c26ecf88ae75Eli Friedmannamespace ComplexConstexpr { 11097ead5c7b6fd48cf549e55b4db499c26ecf88ae75Eli Friedman constexpr _Complex float test1 = {}; 11107ead5c7b6fd48cf549e55b4db499c26ecf88ae75Eli Friedman constexpr _Complex float test2 = {1}; 11117ead5c7b6fd48cf549e55b4db499c26ecf88ae75Eli Friedman constexpr _Complex double test3 = {1,2}; 11127ead5c7b6fd48cf549e55b4db499c26ecf88ae75Eli Friedman constexpr _Complex int test4 = {4}; 11137ead5c7b6fd48cf549e55b4db499c26ecf88ae75Eli Friedman constexpr _Complex int test5 = 4; 11147ead5c7b6fd48cf549e55b4db499c26ecf88ae75Eli Friedman constexpr _Complex int test6 = {5,6}; 1115f6c17a439f3320ac620639a3ee66dbdabb93810cEli Friedman typedef _Complex float fcomplex; 1116f6c17a439f3320ac620639a3ee66dbdabb93810cEli Friedman constexpr fcomplex test7 = fcomplex(); 111786024013d4c3728122c58fa07a2a67e6c15837efRichard Smith 111886024013d4c3728122c58fa07a2a67e6c15837efRichard Smith constexpr const double &t2r = __real test3; 111986024013d4c3728122c58fa07a2a67e6c15837efRichard Smith constexpr const double &t2i = __imag test3; 112086024013d4c3728122c58fa07a2a67e6c15837efRichard Smith static_assert(&t2r + 1 == &t2i, ""); 112186024013d4c3728122c58fa07a2a67e6c15837efRichard Smith static_assert(t2r == 1.0, ""); 112286024013d4c3728122c58fa07a2a67e6c15837efRichard Smith static_assert(t2i == 2.0, ""); 112386024013d4c3728122c58fa07a2a67e6c15837efRichard Smith constexpr const double *t2p = &t2r; 112486024013d4c3728122c58fa07a2a67e6c15837efRichard Smith static_assert(t2p[-1] == 0.0, ""); // expected-error {{constant expr}} expected-note {{cannot refer to element -1 of array of 2 elements}} 112586024013d4c3728122c58fa07a2a67e6c15837efRichard Smith static_assert(t2p[0] == 1.0, ""); 112686024013d4c3728122c58fa07a2a67e6c15837efRichard Smith static_assert(t2p[1] == 2.0, ""); 112786024013d4c3728122c58fa07a2a67e6c15837efRichard Smith static_assert(t2p[2] == 0.0, ""); // expected-error {{constant expr}} expected-note {{one-past-the-end pointer}} 112886024013d4c3728122c58fa07a2a67e6c15837efRichard Smith static_assert(t2p[3] == 0.0, ""); // expected-error {{constant expr}} expected-note {{cannot refer to element 3 of array of 2 elements}} 112986024013d4c3728122c58fa07a2a67e6c15837efRichard Smith constexpr _Complex float *p = 0; 113086024013d4c3728122c58fa07a2a67e6c15837efRichard Smith constexpr float pr = __real *p; // expected-error {{constant expr}} expected-note {{cannot access real component of null}} 113186024013d4c3728122c58fa07a2a67e6c15837efRichard Smith constexpr float pi = __imag *p; // expected-error {{constant expr}} expected-note {{cannot access imaginary component of null}} 113286024013d4c3728122c58fa07a2a67e6c15837efRichard Smith constexpr const _Complex double *q = &test3 + 1; 113386024013d4c3728122c58fa07a2a67e6c15837efRichard Smith constexpr double qr = __real *q; // expected-error {{constant expr}} expected-note {{cannot access real component of pointer past the end}} 113486024013d4c3728122c58fa07a2a67e6c15837efRichard Smith constexpr double qi = __imag *q; // expected-error {{constant expr}} expected-note {{cannot access imaginary component of pointer past the end}} 113586024013d4c3728122c58fa07a2a67e6c15837efRichard Smith 113686024013d4c3728122c58fa07a2a67e6c15837efRichard Smith static_assert(__real test6 == 5, ""); 113786024013d4c3728122c58fa07a2a67e6c15837efRichard Smith static_assert(__imag test6 == 6, ""); 113886024013d4c3728122c58fa07a2a67e6c15837efRichard Smith static_assert(&__imag test6 == &__real test6 + 1, ""); 11397ead5c7b6fd48cf549e55b4db499c26ecf88ae75Eli Friedman} 11406b3014b07c40a6ed8b0c8ed63950df02eeb82c28Eli Friedman 11416b3014b07c40a6ed8b0c8ed63950df02eeb82c28Eli Friedmannamespace InstantiateCaseStmt { 11426b3014b07c40a6ed8b0c8ed63950df02eeb82c28Eli Friedman template<int x> constexpr int f() { return x; } 11436b3014b07c40a6ed8b0c8ed63950df02eeb82c28Eli Friedman template<int x> int g(int c) { switch(c) { case f<x>(): return 1; } return 0; } 11446b3014b07c40a6ed8b0c8ed63950df02eeb82c28Eli Friedman int gg(int c) { return g<4>(c); } 11456b3014b07c40a6ed8b0c8ed63950df02eeb82c28Eli Friedman} 1146495f42a32610c03591b49cd06ac09c5408742f86Richard Smith 1147495f42a32610c03591b49cd06ac09c5408742f86Richard Smithnamespace ConvertedConstantExpr { 1148495f42a32610c03591b49cd06ac09c5408742f86Richard Smith extern int &m; 1149495f42a32610c03591b49cd06ac09c5408742f86Richard Smith extern int &n; 1150495f42a32610c03591b49cd06ac09c5408742f86Richard Smith 1151495f42a32610c03591b49cd06ac09c5408742f86Richard Smith constexpr int k = 4; 1152495f42a32610c03591b49cd06ac09c5408742f86Richard Smith int &m = const_cast<int&>(k); 1153495f42a32610c03591b49cd06ac09c5408742f86Richard Smith 1154495f42a32610c03591b49cd06ac09c5408742f86Richard Smith // If we have nothing more interesting to say, ensure we don't produce a 1155495f42a32610c03591b49cd06ac09c5408742f86Richard Smith // useless note and instead just point to the non-constant subexpression. 1156495f42a32610c03591b49cd06ac09c5408742f86Richard Smith enum class E { 1157495f42a32610c03591b49cd06ac09c5408742f86Richard Smith em = m, 1158495f42a32610c03591b49cd06ac09c5408742f86Richard Smith en = n, // expected-error {{not a constant expression}} 1159495f42a32610c03591b49cd06ac09c5408742f86Richard Smith eo = (m + 1160495f42a32610c03591b49cd06ac09c5408742f86Richard Smith n // expected-error {{not a constant expression}} 1161495f42a32610c03591b49cd06ac09c5408742f86Richard Smith ), 1162495f42a32610c03591b49cd06ac09c5408742f86Richard Smith eq = reinterpret_cast<int>((int*)0) // expected-error {{not a constant expression}} expected-note {{reinterpret_cast}} 1163495f42a32610c03591b49cd06ac09c5408742f86Richard Smith }; 1164495f42a32610c03591b49cd06ac09c5408742f86Richard Smith} 1165d9b02e726262e4009dda830998bb934172ac0020Richard Smith 1166d9b02e726262e4009dda830998bb934172ac0020Richard Smithnamespace IndirectField { 1167d9b02e726262e4009dda830998bb934172ac0020Richard Smith struct S { 1168d9b02e726262e4009dda830998bb934172ac0020Richard Smith struct { // expected-warning {{GNU extension}} 1169f2705196d83a162665d4350bf3bb464972974ee3Richard Smith union { // expected-warning {{declared in an anonymous struct}} 1170f2705196d83a162665d4350bf3bb464972974ee3Richard Smith struct { // expected-warning {{GNU extension}} expected-warning {{declared in an anonymous union}} 1171d9b02e726262e4009dda830998bb934172ac0020Richard Smith int a; 1172d9b02e726262e4009dda830998bb934172ac0020Richard Smith int b; 1173d9b02e726262e4009dda830998bb934172ac0020Richard Smith }; 1174d9b02e726262e4009dda830998bb934172ac0020Richard Smith int c; 1175d9b02e726262e4009dda830998bb934172ac0020Richard Smith }; 1176d9b02e726262e4009dda830998bb934172ac0020Richard Smith int d; 1177d9b02e726262e4009dda830998bb934172ac0020Richard Smith }; 1178d9b02e726262e4009dda830998bb934172ac0020Richard Smith union { 1179d9b02e726262e4009dda830998bb934172ac0020Richard Smith int e; 1180d9b02e726262e4009dda830998bb934172ac0020Richard Smith int f; 1181d9b02e726262e4009dda830998bb934172ac0020Richard Smith }; 1182d9b02e726262e4009dda830998bb934172ac0020Richard Smith constexpr S(int a, int b, int d, int e) : a(a), b(b), d(d), e(e) {} 1183d9b02e726262e4009dda830998bb934172ac0020Richard Smith constexpr S(int c, int d, int f) : c(c), d(d), f(f) {} 1184d9b02e726262e4009dda830998bb934172ac0020Richard Smith }; 1185d9b02e726262e4009dda830998bb934172ac0020Richard Smith 1186d9b02e726262e4009dda830998bb934172ac0020Richard Smith constexpr S s1(1, 2, 3, 4); 1187d9b02e726262e4009dda830998bb934172ac0020Richard Smith constexpr S s2(5, 6, 7); 1188d9b02e726262e4009dda830998bb934172ac0020Richard Smith 1189d9b02e726262e4009dda830998bb934172ac0020Richard Smith // FIXME: The diagnostics here do a very poor job of explaining which unnamed 1190d9b02e726262e4009dda830998bb934172ac0020Richard Smith // member is active and which is requested. 1191d9b02e726262e4009dda830998bb934172ac0020Richard Smith static_assert(s1.a == 1, ""); 1192d9b02e726262e4009dda830998bb934172ac0020Richard Smith static_assert(s1.b == 2, ""); 1193d9b02e726262e4009dda830998bb934172ac0020Richard Smith static_assert(s1.c == 0, ""); // expected-error {{constant expression}} expected-note {{union with active member}} 1194d9b02e726262e4009dda830998bb934172ac0020Richard Smith static_assert(s1.d == 3, ""); 1195d9b02e726262e4009dda830998bb934172ac0020Richard Smith static_assert(s1.e == 4, ""); 1196d9b02e726262e4009dda830998bb934172ac0020Richard Smith static_assert(s1.f == 0, ""); // expected-error {{constant expression}} expected-note {{union with active member}} 1197d9b02e726262e4009dda830998bb934172ac0020Richard Smith 1198d9b02e726262e4009dda830998bb934172ac0020Richard Smith static_assert(s2.a == 0, ""); // expected-error {{constant expression}} expected-note {{union with active member}} 1199d9b02e726262e4009dda830998bb934172ac0020Richard Smith static_assert(s2.b == 0, ""); // expected-error {{constant expression}} expected-note {{union with active member}} 1200d9b02e726262e4009dda830998bb934172ac0020Richard Smith static_assert(s2.c == 5, ""); 1201d9b02e726262e4009dda830998bb934172ac0020Richard Smith static_assert(s2.d == 6, ""); 1202d9b02e726262e4009dda830998bb934172ac0020Richard Smith static_assert(s2.e == 0, ""); // expected-error {{constant expression}} expected-note {{union with active member}} 1203d9b02e726262e4009dda830998bb934172ac0020Richard Smith static_assert(s2.f == 7, ""); 1204d9b02e726262e4009dda830998bb934172ac0020Richard Smith} 1205f15fda02e9c8c82b4a716618f4010b9af8bff796Richard Smith 1206b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith// DR1405: don't allow reading mutable members in constant expressions. 1207b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smithnamespace MutableMembers { 1208b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith struct MM { 1209b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith mutable int n; // expected-note 3{{declared here}} 1210b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith } constexpr mm = { 4 }; 1211b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith constexpr int mmn = mm.n; // expected-error {{constant expression}} expected-note {{read of mutable member 'n' is not allowed in a constant expression}} 1212b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith int x = (mm.n = 1, 3); 1213b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith constexpr int mmn2 = mm.n; // expected-error {{constant expression}} expected-note {{read of mutable member 'n' is not allowed in a constant expression}} 1214b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith 1215b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith // Here's one reason why allowing this would be a disaster... 1216b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith template<int n> struct Id { int k = n; }; 1217b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith int f() { 1218b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith constexpr MM m = { 0 }; 1219b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith ++m.n; 1220b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith return Id<m.n>().k; // expected-error {{not a constant expression}} expected-note {{read of mutable member 'n' is not allowed in a constant expression}} 1221b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith } 1222b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith 1223b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith struct A { int n; }; 1224b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith struct B { mutable A a; }; // expected-note {{here}} 1225b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith struct C { B b; }; 1226b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith constexpr C c[3] = {}; 1227b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith constexpr int k = c[1].b.a.n; // expected-error {{constant expression}} expected-note {{mutable}} 1228b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith} 1229b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith 1230f15fda02e9c8c82b4a716618f4010b9af8bff796Richard Smithnamespace Fold { 1231f15fda02e9c8c82b4a716618f4010b9af8bff796Richard Smith 1232f15fda02e9c8c82b4a716618f4010b9af8bff796Richard Smith // This macro forces its argument to be constant-folded, even if it's not 1233f15fda02e9c8c82b4a716618f4010b9af8bff796Richard Smith // otherwise a constant expression. 1234f15fda02e9c8c82b4a716618f4010b9af8bff796Richard Smith #define fold(x) (__builtin_constant_p(x) ? (x) : (x)) 1235f15fda02e9c8c82b4a716618f4010b9af8bff796Richard Smith 1236f15fda02e9c8c82b4a716618f4010b9af8bff796Richard Smith constexpr int n = (int)(char*)123; // expected-error {{constant expression}} expected-note {{reinterpret_cast}} 1237f15fda02e9c8c82b4a716618f4010b9af8bff796Richard Smith constexpr int m = fold((int)(char*)123); // ok 1238f15fda02e9c8c82b4a716618f4010b9af8bff796Richard Smith static_assert(m == 123, ""); 1239f15fda02e9c8c82b4a716618f4010b9af8bff796Richard Smith 1240f15fda02e9c8c82b4a716618f4010b9af8bff796Richard Smith #undef fold 1241f15fda02e9c8c82b4a716618f4010b9af8bff796Richard Smith 1242f15fda02e9c8c82b4a716618f4010b9af8bff796Richard Smith} 124383587db1bda97f45d2b5a4189e584e2a18be511aRichard Smith 124483587db1bda97f45d2b5a4189e584e2a18be511aRichard Smithnamespace DR1454 { 124583587db1bda97f45d2b5a4189e584e2a18be511aRichard Smith 124683587db1bda97f45d2b5a4189e584e2a18be511aRichard Smithconstexpr const int &f(const int &n) { return n; } 124783587db1bda97f45d2b5a4189e584e2a18be511aRichard Smithconstexpr int k1 = f(0); // ok 124883587db1bda97f45d2b5a4189e584e2a18be511aRichard Smith 124983587db1bda97f45d2b5a4189e584e2a18be511aRichard Smithstruct Wrap { 125083587db1bda97f45d2b5a4189e584e2a18be511aRichard Smith const int &value; 125183587db1bda97f45d2b5a4189e584e2a18be511aRichard Smith}; 125283587db1bda97f45d2b5a4189e584e2a18be511aRichard Smithconstexpr const Wrap &g(const Wrap &w) { return w; } 125383587db1bda97f45d2b5a4189e584e2a18be511aRichard Smithconstexpr int k2 = g({0}).value; // ok 125483587db1bda97f45d2b5a4189e584e2a18be511aRichard Smith 125583587db1bda97f45d2b5a4189e584e2a18be511aRichard Smithconstexpr const int &i = 0; // expected-error {{constant expression}} expected-note {{temporary}} expected-note 2{{here}} 125683587db1bda97f45d2b5a4189e584e2a18be511aRichard Smithconstexpr const int j = i; // expected-error {{constant expression}} expected-note {{initializer of 'i' is not a constant expression}} 125783587db1bda97f45d2b5a4189e584e2a18be511aRichard Smith 125883587db1bda97f45d2b5a4189e584e2a18be511aRichard Smith} 125974e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith 126074e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smithnamespace RecursiveOpaqueExpr { 126174e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith template<typename Iter> 126274e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith constexpr auto LastNonzero(Iter p, Iter q) -> decltype(+*p) { 126374e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith return p != q ? (LastNonzero(p+1, q) ?: *p) : 0; // expected-warning {{GNU}} 126474e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith } 126574e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith 126674e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith constexpr int arr1[] = { 1, 0, 0, 3, 0, 2, 0, 4, 0, 0 }; 126774e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith static_assert(LastNonzero(begin(arr1), end(arr1)) == 4, ""); 126874e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith 126974e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith constexpr int arr2[] = { 1, 0, 0, 3, 0, 2, 0, 4, 0, 5 }; 127074e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith static_assert(LastNonzero(begin(arr2), end(arr2)) == 5, ""); 1271e92b1f4917bfb669a09d220dc979fc3676df4da8Richard Smith 1272e92b1f4917bfb669a09d220dc979fc3676df4da8Richard Smith constexpr int arr3[] = { 1273e92b1f4917bfb669a09d220dc979fc3676df4da8Richard Smith 1, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 1274e92b1f4917bfb669a09d220dc979fc3676df4da8Richard Smith 1, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 1275e92b1f4917bfb669a09d220dc979fc3676df4da8Richard Smith 1, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 1276e92b1f4917bfb669a09d220dc979fc3676df4da8Richard Smith 1, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 1277e92b1f4917bfb669a09d220dc979fc3676df4da8Richard Smith 1, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 1278e92b1f4917bfb669a09d220dc979fc3676df4da8Richard Smith 1, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 1279e92b1f4917bfb669a09d220dc979fc3676df4da8Richard Smith 1, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 1280e92b1f4917bfb669a09d220dc979fc3676df4da8Richard Smith 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }; 1281e92b1f4917bfb669a09d220dc979fc3676df4da8Richard Smith static_assert(LastNonzero(begin(arr3), end(arr3)) == 2, ""); 128274e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith} 128374e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith 128474e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smithnamespace VLASizeof { 128574e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith 128674e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith void f(int k) { 128774e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith int arr[k]; // expected-warning {{C99}} 128874e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith constexpr int n = 1 + 128974e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith sizeof(arr) // expected-error {{constant expression}} 129074e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith * 3; 129174e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith } 129274e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith} 1293b78ae9716576399145786b93f687943f8b197170Richard Smith 1294b78ae9716576399145786b93f687943f8b197170Richard Smithnamespace CompoundLiteral { 1295b78ae9716576399145786b93f687943f8b197170Richard Smith // FIXME: 1296b78ae9716576399145786b93f687943f8b197170Richard Smith // We don't model the semantics of this correctly: the compound literal is 1297b78ae9716576399145786b93f687943f8b197170Richard Smith // represented as a prvalue in the AST, but actually behaves like an lvalue. 1298b78ae9716576399145786b93f687943f8b197170Richard Smith // We treat the compound literal as a temporary and refuse to produce a 1299b78ae9716576399145786b93f687943f8b197170Richard Smith // pointer to it. This is OK: we're not required to treat this as a constant 1300b78ae9716576399145786b93f687943f8b197170Richard Smith // in C++, and in C we model compound literals as lvalues. 1301b78ae9716576399145786b93f687943f8b197170Richard Smith constexpr int *p = (int*)(int[1]){0}; // expected-warning {{C99}} expected-error {{constant expression}} expected-note 2{{temporary}} 1302b78ae9716576399145786b93f687943f8b197170Richard Smith} 13034b1f684416980ef6f1a7cb9e6af9c4fa4a164617Richard Smith 13044b1f684416980ef6f1a7cb9e6af9c4fa4a164617Richard Smithnamespace Vector { 13054b1f684416980ef6f1a7cb9e6af9c4fa4a164617Richard Smith typedef int __attribute__((vector_size(16))) VI4; 13064b1f684416980ef6f1a7cb9e6af9c4fa4a164617Richard Smith constexpr VI4 f(int n) { 13074b1f684416980ef6f1a7cb9e6af9c4fa4a164617Richard Smith return VI4 { n * 3, n + 4, n - 5, n / 6 }; 13084b1f684416980ef6f1a7cb9e6af9c4fa4a164617Richard Smith } 13094b1f684416980ef6f1a7cb9e6af9c4fa4a164617Richard Smith constexpr auto v1 = f(10); 13104b1f684416980ef6f1a7cb9e6af9c4fa4a164617Richard Smith 13114b1f684416980ef6f1a7cb9e6af9c4fa4a164617Richard Smith typedef double __attribute__((vector_size(32))) VD4; 13124b1f684416980ef6f1a7cb9e6af9c4fa4a164617Richard Smith constexpr VD4 g(int n) { 13134b1f684416980ef6f1a7cb9e6af9c4fa4a164617Richard Smith return (VD4) { n / 2.0, n + 1.5, n - 5.4, n * 0.9 }; // expected-warning {{C99}} 13144b1f684416980ef6f1a7cb9e6af9c4fa4a164617Richard Smith } 13154b1f684416980ef6f1a7cb9e6af9c4fa4a164617Richard Smith constexpr auto v2 = g(4); 13164b1f684416980ef6f1a7cb9e6af9c4fa4a164617Richard Smith} 13178d59deec807ed53efcd07855199cdc9c979f447fJohn McCall 13188d59deec807ed53efcd07855199cdc9c979f447fJohn McCall// PR12626, redux 13198d59deec807ed53efcd07855199cdc9c979f447fJohn McCallnamespace InvalidClasses { 13208d59deec807ed53efcd07855199cdc9c979f447fJohn McCall void test0() { 13218d59deec807ed53efcd07855199cdc9c979f447fJohn McCall struct X; // expected-note {{forward declaration}} 13228d59deec807ed53efcd07855199cdc9c979f447fJohn McCall struct Y { bool b; X x; }; // expected-error {{field has incomplete type}} 13238d59deec807ed53efcd07855199cdc9c979f447fJohn McCall Y y; 13248d59deec807ed53efcd07855199cdc9c979f447fJohn McCall auto& b = y.b; 13258d59deec807ed53efcd07855199cdc9c979f447fJohn McCall } 13268d59deec807ed53efcd07855199cdc9c979f447fJohn McCall} 1327dbbecccb8431bb4545fc01c6401abc4253667360Richard Smith 1328a10b97898ee6339c3110e6ca33f178ff52f05238Richard Smithnamespace NamespaceAlias { 1329a10b97898ee6339c3110e6ca33f178ff52f05238Richard Smith constexpr int f() { 1330a10b97898ee6339c3110e6ca33f178ff52f05238Richard Smith namespace NS = NamespaceAlias; // expected-warning {{use of this statement in a constexpr function is a C++1y extension}} 1331a10b97898ee6339c3110e6ca33f178ff52f05238Richard Smith return &NS::f != nullptr; 1332a10b97898ee6339c3110e6ca33f178ff52f05238Richard Smith } 1333a10b97898ee6339c3110e6ca33f178ff52f05238Richard Smith} 1334a10b97898ee6339c3110e6ca33f178ff52f05238Richard Smith 1335622da859b816036290b7e6f046521e4dea388361Richard Smith// Constructors can be implicitly constexpr, even for a non-literal type. 1336622da859b816036290b7e6f046521e4dea388361Richard Smithnamespace ImplicitConstexpr { 1337622da859b816036290b7e6f046521e4dea388361Richard Smith struct Q { Q() = default; Q(const Q&) = default; Q(Q&&) = default; ~Q(); }; // expected-note 3{{here}} 1338604fb38cd943649bee579103d17ca6cda4aad144Richard Smith struct R { constexpr R() noexcept; constexpr R(const R&) noexcept; constexpr R(R&&) noexcept; ~R() noexcept; }; 1339622da859b816036290b7e6f046521e4dea388361Richard Smith struct S { R r; }; // expected-note 3{{here}} 1340604fb38cd943649bee579103d17ca6cda4aad144Richard Smith struct T { T(const T&) noexcept; T(T &&) noexcept; ~T() noexcept; }; 1341622da859b816036290b7e6f046521e4dea388361Richard Smith struct U { T t; }; // expected-note 3{{here}} 1342622da859b816036290b7e6f046521e4dea388361Richard Smith static_assert(!__is_literal_type(Q), ""); 1343622da859b816036290b7e6f046521e4dea388361Richard Smith static_assert(!__is_literal_type(R), ""); 1344622da859b816036290b7e6f046521e4dea388361Richard Smith static_assert(!__is_literal_type(S), ""); 1345622da859b816036290b7e6f046521e4dea388361Richard Smith static_assert(!__is_literal_type(T), ""); 1346622da859b816036290b7e6f046521e4dea388361Richard Smith static_assert(!__is_literal_type(U), ""); 1347622da859b816036290b7e6f046521e4dea388361Richard Smith struct Test { 1348622da859b816036290b7e6f046521e4dea388361Richard Smith friend Q::Q() noexcept; // expected-error {{follows constexpr}} 1349622da859b816036290b7e6f046521e4dea388361Richard Smith friend Q::Q(Q&&) noexcept; // expected-error {{follows constexpr}} 1350622da859b816036290b7e6f046521e4dea388361Richard Smith friend Q::Q(const Q&) noexcept; // expected-error {{follows constexpr}} 1351622da859b816036290b7e6f046521e4dea388361Richard Smith friend S::S() noexcept; // expected-error {{follows constexpr}} 1352622da859b816036290b7e6f046521e4dea388361Richard Smith friend S::S(S&&) noexcept; // expected-error {{follows constexpr}} 1353622da859b816036290b7e6f046521e4dea388361Richard Smith friend S::S(const S&) noexcept; // expected-error {{follows constexpr}} 1354622da859b816036290b7e6f046521e4dea388361Richard Smith friend constexpr U::U() noexcept; // expected-error {{follows non-constexpr}} 1355622da859b816036290b7e6f046521e4dea388361Richard Smith friend constexpr U::U(U&&) noexcept; // expected-error {{follows non-constexpr}} 1356622da859b816036290b7e6f046521e4dea388361Richard Smith friend constexpr U::U(const U&) noexcept; // expected-error {{follows non-constexpr}} 1357622da859b816036290b7e6f046521e4dea388361Richard Smith }; 1358622da859b816036290b7e6f046521e4dea388361Richard Smith} 1359622da859b816036290b7e6f046521e4dea388361Richard Smith 1360dbbecccb8431bb4545fc01c6401abc4253667360Richard Smith// Indirectly test that an implicit lvalue to xvalue conversion performed for 1361dbbecccb8431bb4545fc01c6401abc4253667360Richard Smith// an NRVO move operation isn't implemented as CK_LValueToRValue. 1362dbbecccb8431bb4545fc01c6401abc4253667360Richard Smithnamespace PR12826 { 1363dbbecccb8431bb4545fc01c6401abc4253667360Richard Smith struct Foo {}; 1364dbbecccb8431bb4545fc01c6401abc4253667360Richard Smith constexpr Foo id(Foo x) { return x; } 1365dbbecccb8431bb4545fc01c6401abc4253667360Richard Smith constexpr Foo res(id(Foo())); 1366dbbecccb8431bb4545fc01c6401abc4253667360Richard Smith} 1367f4bb8d06c4f1665f89a9e9ddd61f2a2d26904da0Richard Smith 1368f4bb8d06c4f1665f89a9e9ddd61f2a2d26904da0Richard Smithnamespace PR13273 { 1369f4bb8d06c4f1665f89a9e9ddd61f2a2d26904da0Richard Smith struct U { 1370f4bb8d06c4f1665f89a9e9ddd61f2a2d26904da0Richard Smith int t; 1371f4bb8d06c4f1665f89a9e9ddd61f2a2d26904da0Richard Smith U() = default; 1372f4bb8d06c4f1665f89a9e9ddd61f2a2d26904da0Richard Smith }; 1373f4bb8d06c4f1665f89a9e9ddd61f2a2d26904da0Richard Smith 1374f4bb8d06c4f1665f89a9e9ddd61f2a2d26904da0Richard Smith struct S : U { 1375f4bb8d06c4f1665f89a9e9ddd61f2a2d26904da0Richard Smith S() = default; 1376f4bb8d06c4f1665f89a9e9ddd61f2a2d26904da0Richard Smith }; 1377f4bb8d06c4f1665f89a9e9ddd61f2a2d26904da0Richard Smith 1378f4bb8d06c4f1665f89a9e9ddd61f2a2d26904da0Richard Smith // S's default constructor isn't constexpr, because U's default constructor 1379f4bb8d06c4f1665f89a9e9ddd61f2a2d26904da0Richard Smith // doesn't initialize 't', but it's trivial, so value-initialization doesn't 1380f4bb8d06c4f1665f89a9e9ddd61f2a2d26904da0Richard Smith // actually call it. 1381f4bb8d06c4f1665f89a9e9ddd61f2a2d26904da0Richard Smith static_assert(S{}.t == 0, ""); 1382f4bb8d06c4f1665f89a9e9ddd61f2a2d26904da0Richard Smith} 138320599392a99956eaac4cf351a0935574090cb6c3Richard Smith 138420599392a99956eaac4cf351a0935574090cb6c3Richard Smithnamespace PR12670 { 138520599392a99956eaac4cf351a0935574090cb6c3Richard Smith struct S { 138620599392a99956eaac4cf351a0935574090cb6c3Richard Smith constexpr S(int a0) : m(a0) {} 138720599392a99956eaac4cf351a0935574090cb6c3Richard Smith constexpr S() : m(6) {} 138820599392a99956eaac4cf351a0935574090cb6c3Richard Smith int m; 138920599392a99956eaac4cf351a0935574090cb6c3Richard Smith }; 139020599392a99956eaac4cf351a0935574090cb6c3Richard Smith constexpr S x[3] = { {4}, 5 }; 139120599392a99956eaac4cf351a0935574090cb6c3Richard Smith static_assert(x[0].m == 4, ""); 139220599392a99956eaac4cf351a0935574090cb6c3Richard Smith static_assert(x[1].m == 5, ""); 139320599392a99956eaac4cf351a0935574090cb6c3Richard Smith static_assert(x[2].m == 6, ""); 139420599392a99956eaac4cf351a0935574090cb6c3Richard Smith} 1395604fb38cd943649bee579103d17ca6cda4aad144Richard Smith 1396604fb38cd943649bee579103d17ca6cda4aad144Richard Smith// Indirectly test that an implicit lvalue-to-rvalue conversion is performed 1397604fb38cd943649bee579103d17ca6cda4aad144Richard Smith// when a conditional operator has one argument of type void and where the other 1398604fb38cd943649bee579103d17ca6cda4aad144Richard Smith// is a glvalue of class type. 1399604fb38cd943649bee579103d17ca6cda4aad144Richard Smithnamespace ConditionalLValToRVal { 1400604fb38cd943649bee579103d17ca6cda4aad144Richard Smith struct A { 1401604fb38cd943649bee579103d17ca6cda4aad144Richard Smith constexpr A(int a) : v(a) {} 1402604fb38cd943649bee579103d17ca6cda4aad144Richard Smith int v; 1403604fb38cd943649bee579103d17ca6cda4aad144Richard Smith }; 1404604fb38cd943649bee579103d17ca6cda4aad144Richard Smith 1405604fb38cd943649bee579103d17ca6cda4aad144Richard Smith constexpr A f(const A &a) { 1406604fb38cd943649bee579103d17ca6cda4aad144Richard Smith return a.v == 0 ? throw a : a; 1407604fb38cd943649bee579103d17ca6cda4aad144Richard Smith } 1408604fb38cd943649bee579103d17ca6cda4aad144Richard Smith 1409604fb38cd943649bee579103d17ca6cda4aad144Richard Smith constexpr A a(4); 1410604fb38cd943649bee579103d17ca6cda4aad144Richard Smith static_assert(f(a).v == 4, ""); 1411604fb38cd943649bee579103d17ca6cda4aad144Richard Smith} 141229f431b3e310ae6bd367dccf5a2794ad1cac9592Hans Wennborg 141329f431b3e310ae6bd367dccf5a2794ad1cac9592Hans Wennborgnamespace TLS { 141429f431b3e310ae6bd367dccf5a2794ad1cac9592Hans Wennborg __thread int n; 141548def65d1cfbd020c5d4a7e542a00d63808c6060Hans Wennborg int m; 141648def65d1cfbd020c5d4a7e542a00d63808c6060Hans Wennborg 141748def65d1cfbd020c5d4a7e542a00d63808c6060Hans Wennborg constexpr bool b = &n == &n; 141848def65d1cfbd020c5d4a7e542a00d63808c6060Hans Wennborg 141948def65d1cfbd020c5d4a7e542a00d63808c6060Hans Wennborg constexpr int *p = &n; // expected-error{{constexpr variable 'p' must be initialized by a constant expression}} 142048def65d1cfbd020c5d4a7e542a00d63808c6060Hans Wennborg 142148def65d1cfbd020c5d4a7e542a00d63808c6060Hans Wennborg constexpr int *f() { return &n; } 142248def65d1cfbd020c5d4a7e542a00d63808c6060Hans Wennborg constexpr int *q = f(); // expected-error{{constexpr variable 'q' must be initialized by a constant expression}} 142348def65d1cfbd020c5d4a7e542a00d63808c6060Hans Wennborg constexpr bool c = f() == f(); 142448def65d1cfbd020c5d4a7e542a00d63808c6060Hans Wennborg 142548def65d1cfbd020c5d4a7e542a00d63808c6060Hans Wennborg constexpr int *g() { return &m; } 142648def65d1cfbd020c5d4a7e542a00d63808c6060Hans Wennborg constexpr int *r = g(); 142729f431b3e310ae6bd367dccf5a2794ad1cac9592Hans Wennborg} 142801cad02220180b9646525295f502c00c64a172d0Richard Smith 142901cad02220180b9646525295f502c00c64a172d0Richard Smithnamespace Void { 143001cad02220180b9646525295f502c00c64a172d0Richard Smith constexpr void f() { return; } // expected-error{{constexpr function's return type 'void' is not a literal type}} 143101cad02220180b9646525295f502c00c64a172d0Richard Smith 143201cad02220180b9646525295f502c00c64a172d0Richard Smith void assert_failed(const char *msg, const char *file, int line); // expected-note {{declared here}} 143301cad02220180b9646525295f502c00c64a172d0Richard Smith#define ASSERT(expr) ((expr) ? static_cast<void>(0) : assert_failed(#expr, __FILE__, __LINE__)) 143401cad02220180b9646525295f502c00c64a172d0Richard Smith template<typename T, size_t S> 143501cad02220180b9646525295f502c00c64a172d0Richard Smith constexpr T get(T (&a)[S], size_t k) { 143601cad02220180b9646525295f502c00c64a172d0Richard Smith return ASSERT(k > 0 && k < S), a[k]; // expected-note{{non-constexpr function 'assert_failed'}} 143701cad02220180b9646525295f502c00c64a172d0Richard Smith } 143801cad02220180b9646525295f502c00c64a172d0Richard Smith#undef ASSERT 143901cad02220180b9646525295f502c00c64a172d0Richard Smith template int get(int (&a)[4], size_t); 144001cad02220180b9646525295f502c00c64a172d0Richard Smith constexpr int arr[] = { 4, 1, 2, 3, 4 }; 144101cad02220180b9646525295f502c00c64a172d0Richard Smith static_assert(get(arr, 1) == 1, ""); 144201cad02220180b9646525295f502c00c64a172d0Richard Smith static_assert(get(arr, 4) == 4, ""); 144301cad02220180b9646525295f502c00c64a172d0Richard Smith static_assert(get(arr, 0) == 4, ""); // expected-error{{not an integral constant expression}} \ 144401cad02220180b9646525295f502c00c64a172d0Richard Smith // expected-note{{in call to 'get(arr, 0)'}} 144501cad02220180b9646525295f502c00c64a172d0Richard Smith} 14469be36ab27b874b404099650e0c29bc92f3c7662dRichard Smith 14479be36ab27b874b404099650e0c29bc92f3c7662dRichard Smithnamespace std { struct type_info; } 14489be36ab27b874b404099650e0c29bc92f3c7662dRichard Smith 14499be36ab27b874b404099650e0c29bc92f3c7662dRichard Smithnamespace TypeId { 14509be36ab27b874b404099650e0c29bc92f3c7662dRichard Smith struct A { virtual ~A(); }; 14519be36ab27b874b404099650e0c29bc92f3c7662dRichard Smith A f(); 14529be36ab27b874b404099650e0c29bc92f3c7662dRichard Smith A &g(); 14539be36ab27b874b404099650e0c29bc92f3c7662dRichard Smith constexpr auto &x = typeid(f()); 14549be36ab27b874b404099650e0c29bc92f3c7662dRichard Smith constexpr auto &y = typeid(g()); // expected-error{{constant expression}} \ 14559be36ab27b874b404099650e0c29bc92f3c7662dRichard Smith // expected-note{{typeid applied to expression of polymorphic type 'TypeId::A' is not allowed in a constant expression}} 14569be36ab27b874b404099650e0c29bc92f3c7662dRichard Smith} 14579568f0c13a84695c5cc064e7c32412f84604cb1eRichard Smith 14589568f0c13a84695c5cc064e7c32412f84604cb1eRichard Smithnamespace PR14203 { 14599568f0c13a84695c5cc064e7c32412f84604cb1eRichard Smith struct duration { 14609568f0c13a84695c5cc064e7c32412f84604cb1eRichard Smith constexpr duration() {} 14619568f0c13a84695c5cc064e7c32412f84604cb1eRichard Smith constexpr operator int() const { return 0; } 14629568f0c13a84695c5cc064e7c32412f84604cb1eRichard Smith }; 14639568f0c13a84695c5cc064e7c32412f84604cb1eRichard Smith template<typename T> void f() { 14649568f0c13a84695c5cc064e7c32412f84604cb1eRichard Smith // If we want to evaluate this at the point of the template definition, we 14659568f0c13a84695c5cc064e7c32412f84604cb1eRichard Smith // need to trigger the implicit definition of the move constructor at that 14669568f0c13a84695c5cc064e7c32412f84604cb1eRichard Smith // point. 14679568f0c13a84695c5cc064e7c32412f84604cb1eRichard Smith // FIXME: C++ does not permit us to implicitly define it at the appropriate 14689568f0c13a84695c5cc064e7c32412f84604cb1eRichard Smith // times, since it is only allowed to be implicitly defined when it is 14699568f0c13a84695c5cc064e7c32412f84604cb1eRichard Smith // odr-used. 14709568f0c13a84695c5cc064e7c32412f84604cb1eRichard Smith constexpr duration d = duration(); 14719568f0c13a84695c5cc064e7c32412f84604cb1eRichard Smith } 14729568f0c13a84695c5cc064e7c32412f84604cb1eRichard Smith // FIXME: It's unclear whether this is valid. On the one hand, we're not 14739568f0c13a84695c5cc064e7c32412f84604cb1eRichard Smith // allowed to generate a move constructor. On the other hand, if we did, 1474ce2661f9ccb85de1aacaa7c3ea414a757f5986f6Richard Smith // this would be a constant expression. For now, we generate a move 1475ce2661f9ccb85de1aacaa7c3ea414a757f5986f6Richard Smith // constructor here. 1476ce2661f9ccb85de1aacaa7c3ea414a757f5986f6Richard Smith int n = sizeof(short{duration(duration())}); 14779568f0c13a84695c5cc064e7c32412f84604cb1eRichard Smith} 147899ad35921aa6c1b200b6432c066961f930fce1e1Richard Smith 147999ad35921aa6c1b200b6432c066961f930fce1e1Richard Smithnamespace ArrayEltInit { 148099ad35921aa6c1b200b6432c066961f930fce1e1Richard Smith struct A { 148199ad35921aa6c1b200b6432c066961f930fce1e1Richard Smith constexpr A() : p(&p) {} 148299ad35921aa6c1b200b6432c066961f930fce1e1Richard Smith void *p; 148399ad35921aa6c1b200b6432c066961f930fce1e1Richard Smith }; 148499ad35921aa6c1b200b6432c066961f930fce1e1Richard Smith constexpr A a[10]; 148599ad35921aa6c1b200b6432c066961f930fce1e1Richard Smith static_assert(a[0].p == &a[0].p, ""); 148699ad35921aa6c1b200b6432c066961f930fce1e1Richard Smith static_assert(a[9].p == &a[9].p, ""); 148799ad35921aa6c1b200b6432c066961f930fce1e1Richard Smith static_assert(a[0].p != &a[9].p, ""); 148899ad35921aa6c1b200b6432c066961f930fce1e1Richard Smith static_assert(a[9].p != &a[0].p, ""); 148999ad35921aa6c1b200b6432c066961f930fce1e1Richard Smith 149099ad35921aa6c1b200b6432c066961f930fce1e1Richard Smith constexpr A b[10] = {}; 149199ad35921aa6c1b200b6432c066961f930fce1e1Richard Smith static_assert(b[0].p == &b[0].p, ""); 149299ad35921aa6c1b200b6432c066961f930fce1e1Richard Smith static_assert(b[9].p == &b[9].p, ""); 149399ad35921aa6c1b200b6432c066961f930fce1e1Richard Smith static_assert(b[0].p != &b[9].p, ""); 149499ad35921aa6c1b200b6432c066961f930fce1e1Richard Smith static_assert(b[9].p != &b[0].p, ""); 149599ad35921aa6c1b200b6432c066961f930fce1e1Richard Smith} 1496a07a6c3e756d0a6a5baa2cad9d165f79f0fb1b42Richard Smith 1497a07a6c3e756d0a6a5baa2cad9d165f79f0fb1b42Richard Smithnamespace PR15884 { 1498a07a6c3e756d0a6a5baa2cad9d165f79f0fb1b42Richard Smith struct S {}; 1499a07a6c3e756d0a6a5baa2cad9d165f79f0fb1b42Richard Smith constexpr S f() { return {}; } 1500a07a6c3e756d0a6a5baa2cad9d165f79f0fb1b42Richard Smith constexpr S *p = &f(); 1501a07a6c3e756d0a6a5baa2cad9d165f79f0fb1b42Richard Smith // expected-error@-1 {{taking the address of a temporary}} 1502a07a6c3e756d0a6a5baa2cad9d165f79f0fb1b42Richard Smith // expected-error@-2 {{constexpr variable 'p' must be initialized by a constant expression}} 1503a07a6c3e756d0a6a5baa2cad9d165f79f0fb1b42Richard Smith // expected-note@-3 {{pointer to temporary is not a constant expression}} 1504a07a6c3e756d0a6a5baa2cad9d165f79f0fb1b42Richard Smith // expected-note@-4 {{temporary created here}} 1505a07a6c3e756d0a6a5baa2cad9d165f79f0fb1b42Richard Smith} 1506