constant-expression-cxx11.cpp revision fe587201feaebc69e6d18858bea85c77926b6ecf
11cb2d742eb6635aeab6132ee5f0b5781d39487d7Nico Weber// RUN: %clang_cc1 -triple i686-linux -Wno-string-plus-int -fsyntax-only -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 { 2459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr int zero() { 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}} \ 30760f24e781484250d3602261477d16321db7a157bRichard Smith expected-note {{cast which 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}} \ 31060f24e781484250d3602261477d16321db7a157bRichard Smith expected-note {{cast which 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}} \ 31360f24e781484250d3602261477d16321db7a157bRichard Smith expected-note {{cast which 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}} \ 31660f24e781484250d3602261477d16321db7a157bRichard Smith expected-note {{cast which 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}} 365b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smithconstexpr char c4 = ((char*)(int*)"no reinterpret_casts allowed")[14]; // expected-error {{must be initialized by a constant expression}} expected-note {{cast which 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 41759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 41859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 41959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithnamespace Array { 42059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 4211d238ea926bbdd04356ce475934fcd4cac654c4bRichard Smithtemplate<typename Iter> 4221d238ea926bbdd04356ce475934fcd4cac654c4bRichard Smithconstexpr auto Sum(Iter begin, Iter end) -> decltype(+*begin) { 42359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith return begin == end ? 0 : *begin + Sum(begin+1, end); 42459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 42559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 42659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int xs[] = { 1, 2, 3, 4, 5 }; 42759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int ys[] = { 5, 4, 3, 2, 1 }; 42859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int sum_xs = Sum(begin(xs), end(xs)); 4299eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(sum_xs == 15, ""); 43059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 43159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int ZipFoldR(int (*F)(int x, int y, int c), int n, 43259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith const int *xs, const int *ys, int c) { 433daaefc5381f9aafbb1cb6f88fb5ac6aaf34d65bfRichard Smith return n ? F( 4347098cbd601ad915aed22d4b5850da99359f25bf3Richard Smith *xs, // expected-note {{read of dereferenced one-past-the-end pointer}} 43508d6e032a2a0a8656d12b3b7b93942987bb12eb7Richard Smith *ys, 43608d6e032a2a0a8656d12b3b7b93942987bb12eb7Richard Smith ZipFoldR(F, n-1, xs+1, ys+1, c)) // \ 43708d6e032a2a0a8656d12b3b7b93942987bb12eb7Richard Smith expected-note {{in call to 'ZipFoldR(&SubMul, 2, &xs[4], &ys[4], 1)'}} \ 43808d6e032a2a0a8656d12b3b7b93942987bb12eb7Richard Smith expected-note {{in call to 'ZipFoldR(&SubMul, 1, &xs[5], &ys[5], 1)'}} 43908d6e032a2a0a8656d12b3b7b93942987bb12eb7Richard Smith : c; 44059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 44159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int MulAdd(int x, int y, int c) { return x * y + c; } 44259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int InnerProduct = ZipFoldR(MulAdd, 5, xs, ys, 0); 4439eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(InnerProduct == 35, ""); 44459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 44559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int SubMul(int x, int y, int c) { return (x - y) * c; } 44659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int DiffProd = ZipFoldR(SubMul, 2, xs+3, ys+3, 1); 4479eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(DiffProd == 8, ""); 44808d6e032a2a0a8656d12b3b7b93942987bb12eb7Richard Smithstatic_assert(ZipFoldR(SubMul, 3, xs+3, ys+3, 1), ""); // \ 44908d6e032a2a0a8656d12b3b7b93942987bb12eb7Richard Smith expected-error {{constant expression}} \ 45008d6e032a2a0a8656d12b3b7b93942987bb12eb7Richard Smith expected-note {{in call to 'ZipFoldR(&SubMul, 3, &xs[3], &ys[3], 1)'}} 45159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 45259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr const int *p = xs + 3; 45359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int xs4 = p[1]; // ok 4547098cbd601ad915aed22d4b5850da99359f25bf3Richard Smithconstexpr int xs5 = p[2]; // expected-error {{constant expression}} expected-note {{read of dereferenced one-past-the-end pointer}} 455b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smithconstexpr int xs6 = p[3]; // expected-error {{constant expression}} expected-note {{cannot refer to element 6}} 45659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int xs0 = p[-3]; // ok 457b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smithconstexpr int xs_1 = p[-4]; // expected-error {{constant expression}} expected-note {{cannot refer to element -1}} 45859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 45959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int zs[2][2][2][2] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 }; 4609eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(zs[0][0][0][0] == 1, ""); 4619eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(zs[1][1][1][1] == 16, ""); 4627098cbd601ad915aed22d4b5850da99359f25bf3Richard Smithstatic_assert(zs[0][0][0][2] == 3, ""); // expected-error {{constant expression}} expected-note {{read of dereferenced one-past-the-end pointer}} 4639eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert((&zs[0][0][0][2])[-1] == 2, ""); 4649eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(**(**(zs + 1) + 1) == 11, ""); 465b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard 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}} 466b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smithstatic_assert(*(&(&(*(*&(&zs[2] - 1)[0] + 2 - 2))[2])[-1][2] - 2) == 11, ""); 467b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard 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}} 46859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 46908d6e032a2a0a8656d12b3b7b93942987bb12eb7Richard Smithconstexpr int fail(const int &p) { 470b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smith return (&p)[64]; // expected-note {{cannot refer to element 64 of array of 2 elements}} 47108d6e032a2a0a8656d12b3b7b93942987bb12eb7Richard Smith} 472b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smithstatic_assert(fail(*(&(&(*(*&(&zs[2] - 1)[0] + 2 - 2))[2])[-1][2] - 2)) == 11, ""); // \ 47308d6e032a2a0a8656d12b3b7b93942987bb12eb7Richard Smithexpected-error {{static_assert expression is not an integral constant expression}} \ 47408d6e032a2a0a8656d12b3b7b93942987bb12eb7Richard Smithexpected-note {{in call to 'fail(zs[1][0][1][0])'}} 47508d6e032a2a0a8656d12b3b7b93942987bb12eb7Richard Smith 476d7c56e1114bfe7d461786903bb720d2c6efc05a1Richard Smithconstexpr int arr[40] = { 1, 2, 3, [8] = 4 }; // expected-warning {{C99 feature}} 47759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int SumNonzero(const int *p) { 47859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith return *p + (*p ? SumNonzero(p+1) : 0); 47959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 48059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int CountZero(const int *p, const int *q) { 48159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith return p == q ? 0 : (*p == 0) + CountZero(p+1, q); 48259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 4839eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(SumNonzero(arr) == 6, ""); 4849eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(CountZero(arr, arr + 40) == 36, ""); 48559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 486e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithstruct ArrayElem { 487e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr ArrayElem() : n(0) {} 488e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith int n; 489e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr int f() { return n; } 490e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith}; 491e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithstruct ArrayRVal { 492e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr ArrayRVal() {} 493e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith ArrayElem elems[10]; 494e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith}; 4959eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(ArrayRVal().elems[3].f() == 0, ""); 496e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 49759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 49859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 49959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithnamespace DependentValues { 50059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 50159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithstruct I { int n; typedef I V[10]; }; 50259efe266b804330f4c1f3a1b0ff783e67dd90378Richard SmithI::V x, y; 50359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithtemplate<bool B> struct S { 50459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith int k; 50559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith void f() { 50659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith I::V &cells = B ? x : y; 50759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith I &i = cells[k]; 50859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith switch (i.n) {} 50959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith } 51059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith}; 51159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 51259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 51359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 51459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithnamespace Class { 51559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 51659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithstruct A { constexpr A(int a, int b) : k(a + b) {} int k; }; 51759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int fn(const A &a) { return a.k; } 5189eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(fn(A(4,5)) == 9, ""); 51959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 52059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithstruct B { int n; int m; } constexpr b = { 0, b.n }; // expected-warning {{uninitialized}} 52159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithstruct C { 52259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr C(C *this_) : m(42), n(this_->m) {} // ok 52359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith int m, n; 52459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith}; 52559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithstruct D { 52659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith C c; 52759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr D() : c(&c) {} 52859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith}; 5299eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(D().c.n == 42, ""); 53059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 5316180245e9f63d2927b185ec251fb75aba30f1cacRichard Smithstruct E { 53283587db1bda97f45d2b5a4189e584e2a18be511aRichard Smith constexpr E() : p(&p) {} 53359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith void *p; 53459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith}; 53583587db1bda97f45d2b5a4189e584e2a18be511aRichard Smithconstexpr const E &e1 = E(); // expected-error {{constant expression}} expected-note {{reference to temporary is not a constant expression}} expected-note {{temporary created here}} 53659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith// This is a constant expression if we elide the copy constructor call, and 53759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith// is not a constant expression if we don't! But we do, so it is. 5386180245e9f63d2927b185ec251fb75aba30f1cacRichard Smithconstexpr E e2 = E(); 5396180245e9f63d2927b185ec251fb75aba30f1cacRichard Smithstatic_assert(e2.p == &e2.p, ""); 540099e7f647ccda915513f2b2ec53352dc756082d3Richard Smithconstexpr E e3; 5419eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(e3.p == &e3.p, ""); 54259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 54359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithextern const class F f; 54459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithstruct F { 54559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr F() : p(&f.p) {} 54659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith const void *p; 54759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith}; 548099e7f647ccda915513f2b2ec53352dc756082d3Richard Smithconstexpr F f; 54959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 55059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithstruct G { 55159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith struct T { 55259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr T(T *p) : u1(), u2(p) {} 55359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith union U1 { 55459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr U1() {} 55559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith int a, b = 42; 55659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith } u1; 55759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith union U2 { 55859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr U2(T *p) : c(p->u1.b) {} 55959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith int c, d; 56059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith } u2; 56159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith } t; 56259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr G() : t(&t) {} 56359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} constexpr g; 56459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 5657098cbd601ad915aed22d4b5850da99359f25bf3Richard Smithstatic_assert(g.t.u1.a == 42, ""); // expected-error {{constant expression}} expected-note {{read of member 'a' of union with active member 'b'}} 5669eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(g.t.u1.b == 42, ""); 5679eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(g.t.u2.c == 42, ""); 5687098cbd601ad915aed22d4b5850da99359f25bf3Richard Smithstatic_assert(g.t.u2.d == 42, ""); // expected-error {{constant expression}} expected-note {{read of member 'd' of union with active member 'c'}} 56959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 57059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithstruct S { 57159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith int a, b; 57259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith const S *p; 57359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith double d; 57459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith const char *q; 57559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 57659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr S(int n, const S *p) : a(5), b(n), p(p), d(n), q("hello") {} 57759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith}; 57859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 57959efe266b804330f4c1f3a1b0ff783e67dd90378Richard SmithS global(43, &global); 58059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 5819eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(S(15, &global).b == 15, ""); 58259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 58359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr bool CheckS(const S &s) { 58459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith return s.a == 5 && s.b == 27 && s.p == &global && s.d == 27. && s.q[3] == 'l'; 58559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 5869eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(CheckS(S(27, &global)), ""); 58759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 58859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithstruct Arr { 58959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith char arr[3]; 59059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr Arr() : arr{'x', 'y', 'z'} {} 59159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith}; 59259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int hash(Arr &&a) { 59359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith return a.arr[0] + a.arr[1] * 0x100 + a.arr[2] * 0x10000; 59459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 59559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr int k = hash(Arr()); 5969eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(k == 0x007a7978, ""); 59759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 59859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 59959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithstruct AggregateInit { 60059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith const char &c; 60159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith int n; 60259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith double d; 60359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith int arr[5]; 60459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith void *p; 60559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith}; 60659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 60759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr AggregateInit agg1 = { "hello"[0] }; 60859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 6099eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(strcmp_ce(&agg1.c, "hello") == 0, ""); 6109eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(agg1.n == 0, ""); 6119eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(agg1.d == 0.0, ""); 612b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smithstatic_assert(agg1.arr[-1] == 0, ""); // expected-error {{constant expression}} expected-note {{cannot refer to element -1}} 6139eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(agg1.arr[0] == 0, ""); 6149eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(agg1.arr[4] == 0, ""); 6157098cbd601ad915aed22d4b5850da99359f25bf3Richard Smithstatic_assert(agg1.arr[5] == 0, ""); // expected-error {{constant expression}} expected-note {{read of dereferenced one-past-the-end}} 6169eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(agg1.p == nullptr, ""); 61759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 618fe587201feaebc69e6d18858bea85c77926b6ecfRichard Smithstatic constexpr const unsigned char uc[] = { "foo" }; 619fe587201feaebc69e6d18858bea85c77926b6ecfRichard Smithstatic_assert(uc[0] == 'f', ""); 620fe587201feaebc69e6d18858bea85c77926b6ecfRichard Smithstatic_assert(uc[3] == 0, ""); 621fe587201feaebc69e6d18858bea85c77926b6ecfRichard Smith 62259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithnamespace SimpleDerivedClass { 62359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 62459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithstruct B { 62559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr B(int n) : a(n) {} 62659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith int a; 62759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith}; 62859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithstruct D : B { 62959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr D(int n) : B(n) {} 63059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith}; 63159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr D d(3); 6329eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(d.a == 3, ""); 63359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 63459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 63559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 636e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithstruct Bottom { constexpr Bottom() {} }; 637e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithstruct Base : Bottom { 63859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr Base(int a = 42, const char *b = "test") : a(a), b(b) {} 63959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith int a; 64059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith const char *b; 64159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith}; 642e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithstruct Base2 : Bottom { 64359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr Base2(const int &r) : r(r) {} 64459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith int q = 123; 645099e7f647ccda915513f2b2ec53352dc756082d3Richard Smith const int &r; 64659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith}; 64759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithstruct Derived : Base, Base2 { 64859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr Derived() : Base(76), Base2(a) {} 64959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith int c = r + b[1]; 65059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith}; 65159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 65259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr bool operator==(const Base &a, const Base &b) { 65359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith return a.a == b.a && strcmp_ce(a.b, b.b) == 0; 65459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 65559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 65659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr Base base; 65759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr Base base2(76); 65859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr Derived derived; 6599eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(derived.a == 76, ""); 6609eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(derived.b[2] == 's', ""); 6619eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(derived.c == 76 + 'e', ""); 6629eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(derived.q == 123, ""); 6639eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(derived.r == 76, ""); 664099e7f647ccda915513f2b2ec53352dc756082d3Richard Smithstatic_assert(&derived.r == &derived.a, ""); 66559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 6669eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(!(derived == base), ""); 6679eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(derived == base2, ""); 66859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 669e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithconstexpr Bottom &bot1 = (Base&)derived; 670e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithconstexpr Bottom &bot2 = (Base2&)derived; 6719eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(&bot1 != &bot2, ""); 672e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 673e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithconstexpr Bottom *pb1 = (Base*)&derived; 674e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithconstexpr Bottom *pb2 = (Base2*)&derived; 675f15fda02e9c8c82b4a716618f4010b9af8bff796Richard Smithstatic_assert(&pb1 != &pb2, ""); 6769eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(pb1 == &bot1, ""); 6779eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(pb2 == &bot2, ""); 678e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 679b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smithconstexpr Base2 &fail = (Base2&)bot1; // expected-error {{constant expression}} expected-note {{cannot cast object of dynamic type 'const Class::Derived' to type 'Class::Base2'}} 680b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smithconstexpr Base &fail2 = (Base&)*pb2; // expected-error {{constant expression}} expected-note {{cannot cast object of dynamic type 'const Class::Derived' to type 'Class::Base'}} 681e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithconstexpr Base2 &ok2 = (Base2&)bot2; 6829eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(&ok2 == &derived, ""); 683e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 684b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smithconstexpr Base2 *pfail = (Base2*)pb1; // expected-error {{constant expression}} expected-note {{cannot cast object of dynamic type 'const Class::Derived' to type 'Class::Base2'}} 685b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smithconstexpr Base *pfail2 = (Base*)&bot2; // expected-error {{constant expression}} expected-note {{cannot cast object of dynamic type 'const Class::Derived' to type 'Class::Base'}} 686e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithconstexpr Base2 *pok2 = (Base2*)pb2; 6879eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(pok2 == &derived, ""); 6889eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(&ok2 == pok2, ""); 6899eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert((Base2*)(Derived*)(Base*)pb1 == pok2, ""); 6909eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert((Derived*)(Base*)pb1 == (Derived*)pok2, ""); 691e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 692e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithconstexpr Base *nullB = 42 - 6 * 7; 6939eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert((Bottom*)nullB == 0, ""); 6949eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert((Derived*)nullB == 0, ""); 6959eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert((void*)(Bottom*)nullB == (void*)(Derived*)nullB, ""); 696e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 6977d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smithnamespace ConversionOperators { 6987d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smith 6997d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smithstruct T { 7007d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smith constexpr T(int n) : k(5*n - 3) {} 7017d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smith constexpr operator int() { return k; } 7027d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smith int k; 7037d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smith}; 7047d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smith 7057d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smithstruct S { 7067d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smith constexpr S(int n) : k(2*n + 1) {} 7077d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smith constexpr operator int() { return k; } 7087d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smith constexpr operator T() { return T(k); } 7097d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smith int k; 7107d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smith}; 7117d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smith 7127d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smithconstexpr bool check(T a, T b) { return a == b.k; } 7137d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smith 7147d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smithstatic_assert(S(5) == 11, ""); 7157d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smithstatic_assert(check(S(5), 11), ""); 7167d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smith 7177d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smith} 7187d580a4e9e47dffc3c17aa2b957ac57ca3c4e451Richard Smith 719e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith} 720e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 721e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithnamespace Temporaries { 722e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 723e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithstruct S { 724e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr S() {} 725e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr int f(); 726e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith}; 727e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithstruct T : S { 728e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr T(int n) : S(), n(n) {} 729e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith int n; 730e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith}; 731e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithconstexpr int S::f() { 732e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith // 'this' must be the postfix-expression in a class member access expression, 733e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith // so we can't just use 734e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith // return static_cast<T*>(this)->n; 735e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith return this->*(int(S::*))&T::n; 736e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith} 737e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith// The T temporary is implicitly cast to an S subobject, but we can recover the 738e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith// T full-object via a base-to-derived cast, or a derived-to-base-casted member 739e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith// pointer. 7409eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(T(3).f() == 3, ""); 741e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 742e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithconstexpr int f(const S &s) { 743e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith return static_cast<const T&>(s).n; 744e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith} 745e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithconstexpr int n = f(T(5)); 7469eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(f(T(5)) == 5, ""); 747e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 748f2e4cd760a5836ee8941d1b9be6b2e2c2dde23e6Richard Smithconstexpr bool b(int n) { return &n; } 749f2e4cd760a5836ee8941d1b9be6b2e2c2dde23e6Richard Smithstatic_assert(b(0), ""); 750f2e4cd760a5836ee8941d1b9be6b2e2c2dde23e6Richard Smith 75159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 75259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 75359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithnamespace Union { 75459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 75559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithunion U { 75659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith int a; 75759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith int b; 75859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith}; 75959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 760d7c56e1114bfe7d461786903bb720d2c6efc05a1Richard Smithconstexpr U u[4] = { { .a = 0 }, { .b = 1 }, { .a = 2 }, { .b = 3 } }; // expected-warning 4{{C99 feature}} 7619eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(u[0].a == 0, ""); 7627098cbd601ad915aed22d4b5850da99359f25bf3Richard Smithstatic_assert(u[0].b, ""); // expected-error {{constant expression}} expected-note {{read of member 'b' of union with active member 'a'}} 7639eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(u[1].b == 1, ""); 7647098cbd601ad915aed22d4b5850da99359f25bf3Richard Smithstatic_assert((&u[1].b)[1] == 2, ""); // expected-error {{constant expression}} expected-note {{read of dereferenced one-past-the-end pointer}} 765b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smithstatic_assert(*(&(u[1].b) + 1 + 1) == 3, ""); // expected-error {{constant expression}} expected-note {{cannot refer to element 2 of non-array object}} 7669eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert((&(u[1]) + 1 + 1)->b == 3, ""); 76759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 768ec789163a42a7be654ac34aadb750b508954d53cRichard Smithconstexpr U v = {}; 769ec789163a42a7be654ac34aadb750b508954d53cRichard Smithstatic_assert(v.a == 0, ""); 770ec789163a42a7be654ac34aadb750b508954d53cRichard Smith 771ec789163a42a7be654ac34aadb750b508954d53cRichard Smithunion Empty {}; 772ec789163a42a7be654ac34aadb750b508954d53cRichard Smithconstexpr Empty e = {}; 773ec789163a42a7be654ac34aadb750b508954d53cRichard Smith 774610a60c0e68e34db5a5247d6102e58f37510fef8Richard Smith// Make sure we handle trivial copy constructors for unions. 775610a60c0e68e34db5a5247d6102e58f37510fef8Richard Smithconstexpr U x = {42}; 776610a60c0e68e34db5a5247d6102e58f37510fef8Richard Smithconstexpr U y = x; 777610a60c0e68e34db5a5247d6102e58f37510fef8Richard Smithstatic_assert(y.a == 42, ""); 778610a60c0e68e34db5a5247d6102e58f37510fef8Richard Smithstatic_assert(y.b == 42, ""); // expected-error {{constant expression}} expected-note {{'b' of union with active member 'a'}} 779610a60c0e68e34db5a5247d6102e58f37510fef8Richard Smith 78059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 78159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 782e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithnamespace MemberPointer { 783e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith struct A { 784e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr A(int n) : n(n) {} 785e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith int n; 786e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr int f() { return n + 3; } 787e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith }; 788e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr A a(7); 7899eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(A(5).*&A::n == 5, ""); 7909eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert((&a)->*&A::n == 7, ""); 7919eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert((A(8).*&A::f)() == 11, ""); 7929eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(((&a)->*&A::f)() == 10, ""); 793e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 794e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith struct B : A { 795e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr B(int n, int m) : A(n), m(m) {} 796e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith int m; 797e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr int g() { return n + m + 1; } 798e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith }; 799e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr B b(9, 13); 8009eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(B(4, 11).*&A::n == 4, ""); 8019eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(B(4, 11).*&B::m == 11, ""); 8029eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(B(4, 11).*(int(A::*))&B::m == 11, ""); 8039eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert((&b)->*&A::n == 9, ""); 8049eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert((&b)->*&B::m == 13, ""); 8059eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert((&b)->*(int(A::*))&B::m == 13, ""); 8069eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert((B(4, 11).*&A::f)() == 7, ""); 8079eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert((B(4, 11).*&B::g)() == 16, ""); 8089eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert((B(4, 11).*(int(A::*)()const)&B::g)() == 16, ""); 8099eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(((&b)->*&A::f)() == 12, ""); 8109eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(((&b)->*&B::g)() == 23, ""); 8119eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(((&b)->*(int(A::*)()const)&B::g)() == 23, ""); 812e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 813e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith struct S { 814e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr S(int m, int n, int (S::*pf)() const, int S::*pn) : 815e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith m(m), n(n), pf(pf), pn(pn) {} 816e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr S() : m(), n(), pf(&S::f), pn(&S::n) {} 817e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 818e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr int f() { return this->*pn; } 819e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith virtual int g() const; 820e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 821e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith int m, n; 822e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith int (S::*pf)() const; 823e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith int S::*pn; 824e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith }; 825e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 826e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr int S::*pm = &S::m; 827e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr int S::*pn = &S::n; 828e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr int (S::*pf)() const = &S::f; 829e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr int (S::*pg)() const = &S::g; 830e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 831e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr S s(2, 5, &S::f, &S::m); 832e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 8339eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert((s.*&S::f)() == 2, ""); 8349eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert((s.*s.pf)() == 2, ""); 835e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 836b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith static_assert(pf == &S::f, ""); 837b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith static_assert(pf == s.*&S::pf, ""); 838b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith static_assert(pm == &S::m, ""); 839b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith static_assert(pm != pn, ""); 840b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith static_assert(s.pn != pn, ""); 841b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith static_assert(s.pn == pm, ""); 842b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith static_assert(pg != nullptr, ""); 843b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith static_assert(pf != nullptr, ""); 844b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith static_assert((int S::*)nullptr == nullptr, ""); 845b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith static_assert(pg == pg, ""); // expected-error {{constant expression}} expected-note {{comparison of pointer to virtual member function 'g' has unspecified value}} 846b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith static_assert(pf != pg, ""); // expected-error {{constant expression}} expected-note {{comparison of pointer to virtual member function 'g' has unspecified value}} 847b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith 848e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith template<int n> struct T : T<n-1> {}; 849e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith template<> struct T<0> { int n; }; 850e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith template<> struct T<30> : T<29> { int m; }; 851e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 852e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith T<17> t17; 853e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith T<30> t30; 854e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 855e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr int (T<10>::*deepn) = &T<0>::n; 8569eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(&(t17.*deepn) == &t17.n, ""); 857b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith static_assert(deepn == &T<2>::n, ""); 858e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 859e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr int (T<15>::*deepm) = (int(T<10>::*))&T<30>::m; 860e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr int *pbad = &(t17.*deepm); // expected-error {{constant expression}} 8619eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(&(t30.*deepm) == &t30.m, ""); 862b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith static_assert(deepm == &T<50>::m, ""); 863b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith static_assert(deepm != deepn, ""); 864e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 865e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr T<5> *p17_5 = &t17; 866e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr T<13> *p17_13 = (T<13>*)p17_5; 867b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard 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>'}} 8689eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(&(p17_5->*(int(T<3>::*))deepn) == &t17.n, ""); 8699eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(&(p17_13->*deepn) == &t17.n, ""); 870e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr int *pbad2 = &(p17_13->*(int(T<9>::*))deepm); // expected-error {{constant expression}} 871e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 872e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr T<5> *p30_5 = &t30; 873e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr T<23> *p30_23 = (T<23>*)p30_5; 874e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr T<13> *p30_13 = p30_23; 8759eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(&(p30_5->*(int(T<3>::*))deepn) == &t30.n, ""); 8769eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(&(p30_13->*deepn) == &t30.n, ""); 8779eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(&(p30_23->*deepn) == &t30.n, ""); 8789eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(&(p30_5->*(int(T<2>::*))deepm) == &t30.m, ""); 8799eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(&(((T<17>*)p30_13)->*deepm) == &t30.m, ""); 8809eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(&(p30_23->*deepm) == &t30.m, ""); 881b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith 882b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith struct Base { int n; }; 883b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith template<int N> struct Mid : Base {}; 884b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith struct Derived : Mid<0>, Mid<1> {}; 885b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith static_assert(&Mid<0>::n == &Mid<1>::n, ""); 886b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith static_assert((int Derived::*)(int Mid<0>::*)&Mid<0>::n != 887b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith (int Derived::*)(int Mid<1>::*)&Mid<1>::n, ""); 888b02e4629f78a0c0c0adf9d66b644e5932a781c7eRichard Smith static_assert(&Mid<0>::n == (int Mid<0>::*)&Base::n, ""); 889e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith} 890e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 891e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smithnamespace ArrayBaseDerived { 892e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 893e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith struct Base { 894e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr Base() {} 895e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith int n = 0; 896e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith }; 897e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith struct Derived : Base { 898e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr Derived() {} 899e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr const int *f() { return &n; } 900e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith }; 901e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 902e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr Derived a[10]; 903e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr Derived *pd3 = const_cast<Derived*>(&a[3]); 904e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr Base *pb3 = const_cast<Derived*>(&a[3]); 9059eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(pb3 == pd3, ""); 906e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 907e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith // pb3 does not point to an array element. 908e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr Base *pb4 = pb3 + 1; // ok, one-past-the-end pointer. 909b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smith constexpr int pb4n = pb4->n; // expected-error {{constant expression}} expected-note {{cannot access field of pointer past the end}} 910b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smith constexpr Base *err_pb5 = pb3 + 2; // expected-error {{constant expression}} expected-note {{cannot refer to element 2}} expected-note {{here}} 911b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smith constexpr int err_pb5n = err_pb5->n; // expected-error {{constant expression}} expected-note {{initializer of 'err_pb5' is not a constant expression}} 912b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smith constexpr Base *err_pb2 = pb3 - 1; // expected-error {{constant expression}} expected-note {{cannot refer to element -1}} expected-note {{here}} 913b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smith constexpr int err_pb2n = err_pb2->n; // expected-error {{constant expression}} expected-note {{initializer of 'err_pb2'}} 914e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr Base *pb3a = pb4 - 1; 915e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 916e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith // pb4 does not point to a Derived. 917b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smith constexpr Derived *err_pd4 = (Derived*)pb4; // expected-error {{constant expression}} expected-note {{cannot access derived class of pointer past the end}} 918e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr Derived *pd3a = (Derived*)pb3a; 919e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr int pd3n = pd3a->n; 920e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 921e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith // pd3a still points to the Derived array. 922e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr Derived *pd6 = pd3a + 3; 9239eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert(pd6 == &a[6], ""); 924e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr Derived *pd9 = pd6 + 3; 925e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr Derived *pd10 = pd6 + 4; 926e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr int pd9n = pd9->n; // ok 927b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smith constexpr int err_pd10n = pd10->n; // expected-error {{constant expression}} expected-note {{cannot access base class of pointer past the end}} 928e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr int pd0n = pd10[-10].n; 929b4e85ed51905fc94378d7b4ff62b06e0d08042b7Richard Smith constexpr int err_pdminus1n = pd10[-11].n; // expected-error {{constant expression}} expected-note {{cannot refer to element -1 of}} 930e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 931e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr Base *pb9 = pd9; 932e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith constexpr const int *(Base::*pfb)() const = 933e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith static_cast<const int *(Base::*)() const>(&Derived::f); 9349eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smith static_assert((pb9->*pfb)() == &a[9].n, ""); 935e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith} 936e24f5fc8c763f1b5536b8d70dd510ca959db3a80Richard Smith 93759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithnamespace Complex { 93859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 93959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithclass complex { 94059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith int re, im; 94159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithpublic: 94259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr complex(int re = 0, int im = 0) : re(re), im(im) {} 94359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr complex(const complex &o) : re(o.re), im(o.im) {} 94459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr complex operator-() const { return complex(-re, -im); } 94559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith friend constexpr complex operator+(const complex &l, const complex &r) { 94659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith return complex(l.re + r.re, l.im + r.im); 94759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith } 94859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith friend constexpr complex operator-(const complex &l, const complex &r) { 94959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith return l + -r; 95059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith } 95159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith friend constexpr complex operator*(const complex &l, const complex &r) { 95259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith return complex(l.re * r.re - l.im * r.im, l.re * r.im + l.im * r.re); 95359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith } 95459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith friend constexpr bool operator==(const complex &l, const complex &r) { 95559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith return l.re == r.re && l.im == r.im; 95659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith } 95759efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr bool operator!=(const complex &r) const { 95859efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith return re != r.re || im != r.im; 95959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith } 96059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr int real() const { return re; } 96159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr int imag() const { return im; } 96259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith}; 96359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 96459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr complex i = complex(0, 1); 96559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr complex k = (3 + 4*i) * (6 - 4*i); 9669eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(complex(1,0).real() == 1, ""); 9679eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(complex(1,0).imag() == 0, ""); 9689eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(((complex)1).imag() == 0, ""); 9699eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(k.real() == 34, ""); 9709eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(k.imag() == 12, ""); 9719eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(k - 34 == 12*i, ""); 9729eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert((complex)1 == complex(1), ""); 9739eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert((complex)1 != complex(0, 1), ""); 9749eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(complex(1) == complex(1), ""); 9759eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(complex(1) != complex(0, 1), ""); 97659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr complex makeComplex(int re, int im) { return complex(re, im); } 9779eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(makeComplex(1,0) == complex(1), ""); 9789eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(makeComplex(1,0) != complex(0, 1), ""); 97959efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 98059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithclass complex_wrap : public complex { 98159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithpublic: 98259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr complex_wrap(int re, int im = 0) : complex(re, im) {} 98359efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith constexpr complex_wrap(const complex_wrap &o) : complex(o) {} 98459efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith}; 98559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 9869eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert((complex_wrap)1 == complex(1), ""); 9879eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert((complex)1 != complex_wrap(0, 1), ""); 9889eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(complex(1) == complex_wrap(1), ""); 9899eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(complex_wrap(1) != complex(0, 1), ""); 99059efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smithconstexpr complex_wrap makeComplexWrap(int re, int im) { 99159efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith return complex_wrap(re, im); 99259efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 9939eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(makeComplexWrap(1,0) == complex(1), ""); 9949eed49c2bb0f37bbfefefd0998b6303a686a66c0Richard Smithstatic_assert(makeComplexWrap(1,0) != complex(0, 1), ""); 99559efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith 99659efe266b804330f4c1f3a1b0ff783e67dd90378Richard Smith} 997f59ff8c777379bd54137853a58c58b72fb869152Eli Friedman 998f59ff8c777379bd54137853a58c58b72fb869152Eli Friedmannamespace PR11595 { 999f59ff8c777379bd54137853a58c58b72fb869152Eli Friedman struct A { constexpr bool operator==(int x) { return true; } }; 1000af2c7a194592401394233b7cbcdd3cfd0a7a38ddRichard Smith struct B { B(); A& x; }; 1001af2c7a194592401394233b7cbcdd3cfd0a7a38ddRichard Smith static_assert(B().x == 3, ""); // expected-error {{constant expression}} expected-note {{non-literal type 'PR11595::B' cannot be used in a constant expression}} 1002af2c7a194592401394233b7cbcdd3cfd0a7a38ddRichard Smith 1003745f5147e065900267c85a5568785a1991d4838fRichard Smith constexpr bool f(int k) { // expected-error {{constexpr function never produces a constant expression}} 1004af2c7a194592401394233b7cbcdd3cfd0a7a38ddRichard Smith return B().x == k; // expected-note {{non-literal type 'PR11595::B' cannot be used in a constant expression}} 1005af2c7a194592401394233b7cbcdd3cfd0a7a38ddRichard Smith } 1006f59ff8c777379bd54137853a58c58b72fb869152Eli Friedman} 1007bc6abe93a5d6b1305411f8b6f54c2caa686ddc69Richard Smith 1008bc6abe93a5d6b1305411f8b6f54c2caa686ddc69Richard Smithnamespace ExprWithCleanups { 1009bc6abe93a5d6b1305411f8b6f54c2caa686ddc69Richard Smith struct A { A(); ~A(); int get(); }; 1010bc6abe93a5d6b1305411f8b6f54c2caa686ddc69Richard Smith constexpr int get(bool FromA) { return FromA ? A().get() : 1; } 1011bc6abe93a5d6b1305411f8b6f54c2caa686ddc69Richard Smith constexpr int n = get(false); 1012bc6abe93a5d6b1305411f8b6f54c2caa686ddc69Richard Smith} 10137098cbd601ad915aed22d4b5850da99359f25bf3Richard Smith 10147098cbd601ad915aed22d4b5850da99359f25bf3Richard Smithnamespace Volatile { 10157098cbd601ad915aed22d4b5850da99359f25bf3Richard Smith 10167098cbd601ad915aed22d4b5850da99359f25bf3Richard Smithvolatile constexpr int n1 = 0; // expected-note {{here}} 10177098cbd601ad915aed22d4b5850da99359f25bf3Richard Smithvolatile const int n2 = 0; // expected-note {{here}} 10187098cbd601ad915aed22d4b5850da99359f25bf3Richard Smithint n3 = 37; // expected-note {{declared here}} 10197098cbd601ad915aed22d4b5850da99359f25bf3Richard Smith 10209ec7197796a2730d54ae7f632553b5311b2ba3b5Richard Smithconstexpr int m1 = n1; // expected-error {{constant expression}} expected-note {{read of volatile-qualified type 'const volatile int'}} 10219ec7197796a2730d54ae7f632553b5311b2ba3b5Richard Smithconstexpr int m2 = n2; // expected-error {{constant expression}} expected-note {{read of volatile-qualified type 'const volatile int'}} 10229ec7197796a2730d54ae7f632553b5311b2ba3b5Richard Smithconstexpr int m1b = const_cast<const int&>(n1); // expected-error {{constant expression}} expected-note {{read of volatile object 'n1'}} 10239ec7197796a2730d54ae7f632553b5311b2ba3b5Richard Smithconstexpr int m2b = const_cast<const int&>(n2); // expected-error {{constant expression}} expected-note {{read of volatile object 'n2'}} 10247098cbd601ad915aed22d4b5850da99359f25bf3Richard Smith 10257098cbd601ad915aed22d4b5850da99359f25bf3Richard Smithstruct T { int n; }; 10267098cbd601ad915aed22d4b5850da99359f25bf3Richard Smithconst T t = { 42 }; // expected-note {{declared here}} 10277098cbd601ad915aed22d4b5850da99359f25bf3Richard Smith 10287098cbd601ad915aed22d4b5850da99359f25bf3Richard Smithconstexpr int f(volatile int &&r) { 10299ec7197796a2730d54ae7f632553b5311b2ba3b5Richard Smith return r; // expected-note {{read of volatile-qualified type 'volatile int'}} 10309ec7197796a2730d54ae7f632553b5311b2ba3b5Richard Smith} 10319ec7197796a2730d54ae7f632553b5311b2ba3b5Richard Smithconstexpr int g(volatile int &&r) { 10329ec7197796a2730d54ae7f632553b5311b2ba3b5Richard Smith return const_cast<int&>(r); // expected-note {{read of volatile temporary is not allowed in a constant expression}} 10337098cbd601ad915aed22d4b5850da99359f25bf3Richard Smith} 10347098cbd601ad915aed22d4b5850da99359f25bf3Richard Smithstruct S { 10359ec7197796a2730d54ae7f632553b5311b2ba3b5Richard Smith int j : f(0); // expected-error {{constant expression}} expected-note {{in call to 'f(0)'}} 10369ec7197796a2730d54ae7f632553b5311b2ba3b5Richard Smith int k : g(0); // expected-error {{constant expression}} expected-note {{temporary created here}} expected-note {{in call to 'g(0)'}} 10377098cbd601ad915aed22d4b5850da99359f25bf3Richard Smith int l : n3; // expected-error {{constant expression}} expected-note {{read of non-const variable}} 10387098cbd601ad915aed22d4b5850da99359f25bf3Richard Smith int m : t.n; // expected-error {{constant expression}} expected-note {{read of non-constexpr variable}} 10397098cbd601ad915aed22d4b5850da99359f25bf3Richard Smith}; 10407098cbd601ad915aed22d4b5850da99359f25bf3Richard Smith 10417098cbd601ad915aed22d4b5850da99359f25bf3Richard Smith} 1042dd4b350143c26c030a482f091908a2e077503411Richard Smith 1043dd4b350143c26c030a482f091908a2e077503411Richard Smithnamespace ExternConstexpr { 1044dd4b350143c26c030a482f091908a2e077503411Richard Smith extern constexpr int n = 0; 1045dd4b350143c26c030a482f091908a2e077503411Richard Smith extern constexpr int m; // expected-error {{constexpr variable declaration must be a definition}} 1046dd4b350143c26c030a482f091908a2e077503411Richard Smith void f() { 1047dd4b350143c26c030a482f091908a2e077503411Richard Smith extern constexpr int i; // expected-error {{constexpr variable declaration must be a definition}} 1048dd4b350143c26c030a482f091908a2e077503411Richard Smith constexpr int j = 0; 1049dd4b350143c26c030a482f091908a2e077503411Richard Smith constexpr int k; // expected-error {{default initialization of an object of const type}} 1050dd4b350143c26c030a482f091908a2e077503411Richard Smith } 1051dd4b350143c26c030a482f091908a2e077503411Richard Smith} 10527ead5c7b6fd48cf549e55b4db499c26ecf88ae75Eli Friedman 10537ead5c7b6fd48cf549e55b4db499c26ecf88ae75Eli Friedmannamespace ComplexConstexpr { 10547ead5c7b6fd48cf549e55b4db499c26ecf88ae75Eli Friedman constexpr _Complex float test1 = {}; 10557ead5c7b6fd48cf549e55b4db499c26ecf88ae75Eli Friedman constexpr _Complex float test2 = {1}; 10567ead5c7b6fd48cf549e55b4db499c26ecf88ae75Eli Friedman constexpr _Complex double test3 = {1,2}; 10577ead5c7b6fd48cf549e55b4db499c26ecf88ae75Eli Friedman constexpr _Complex int test4 = {4}; 10587ead5c7b6fd48cf549e55b4db499c26ecf88ae75Eli Friedman constexpr _Complex int test5 = 4; 10597ead5c7b6fd48cf549e55b4db499c26ecf88ae75Eli Friedman constexpr _Complex int test6 = {5,6}; 1060f6c17a439f3320ac620639a3ee66dbdabb93810cEli Friedman typedef _Complex float fcomplex; 1061f6c17a439f3320ac620639a3ee66dbdabb93810cEli Friedman constexpr fcomplex test7 = fcomplex(); 106286024013d4c3728122c58fa07a2a67e6c15837efRichard Smith 106386024013d4c3728122c58fa07a2a67e6c15837efRichard Smith constexpr const double &t2r = __real test3; 106486024013d4c3728122c58fa07a2a67e6c15837efRichard Smith constexpr const double &t2i = __imag test3; 106586024013d4c3728122c58fa07a2a67e6c15837efRichard Smith static_assert(&t2r + 1 == &t2i, ""); 106686024013d4c3728122c58fa07a2a67e6c15837efRichard Smith static_assert(t2r == 1.0, ""); 106786024013d4c3728122c58fa07a2a67e6c15837efRichard Smith static_assert(t2i == 2.0, ""); 106886024013d4c3728122c58fa07a2a67e6c15837efRichard Smith constexpr const double *t2p = &t2r; 106986024013d4c3728122c58fa07a2a67e6c15837efRichard Smith static_assert(t2p[-1] == 0.0, ""); // expected-error {{constant expr}} expected-note {{cannot refer to element -1 of array of 2 elements}} 107086024013d4c3728122c58fa07a2a67e6c15837efRichard Smith static_assert(t2p[0] == 1.0, ""); 107186024013d4c3728122c58fa07a2a67e6c15837efRichard Smith static_assert(t2p[1] == 2.0, ""); 107286024013d4c3728122c58fa07a2a67e6c15837efRichard Smith static_assert(t2p[2] == 0.0, ""); // expected-error {{constant expr}} expected-note {{one-past-the-end pointer}} 107386024013d4c3728122c58fa07a2a67e6c15837efRichard Smith static_assert(t2p[3] == 0.0, ""); // expected-error {{constant expr}} expected-note {{cannot refer to element 3 of array of 2 elements}} 107486024013d4c3728122c58fa07a2a67e6c15837efRichard Smith constexpr _Complex float *p = 0; 107586024013d4c3728122c58fa07a2a67e6c15837efRichard Smith constexpr float pr = __real *p; // expected-error {{constant expr}} expected-note {{cannot access real component of null}} 107686024013d4c3728122c58fa07a2a67e6c15837efRichard Smith constexpr float pi = __imag *p; // expected-error {{constant expr}} expected-note {{cannot access imaginary component of null}} 107786024013d4c3728122c58fa07a2a67e6c15837efRichard Smith constexpr const _Complex double *q = &test3 + 1; 107886024013d4c3728122c58fa07a2a67e6c15837efRichard Smith constexpr double qr = __real *q; // expected-error {{constant expr}} expected-note {{cannot access real component of pointer past the end}} 107986024013d4c3728122c58fa07a2a67e6c15837efRichard Smith constexpr double qi = __imag *q; // expected-error {{constant expr}} expected-note {{cannot access imaginary component of pointer past the end}} 108086024013d4c3728122c58fa07a2a67e6c15837efRichard Smith 108186024013d4c3728122c58fa07a2a67e6c15837efRichard Smith static_assert(__real test6 == 5, ""); 108286024013d4c3728122c58fa07a2a67e6c15837efRichard Smith static_assert(__imag test6 == 6, ""); 108386024013d4c3728122c58fa07a2a67e6c15837efRichard Smith static_assert(&__imag test6 == &__real test6 + 1, ""); 10847ead5c7b6fd48cf549e55b4db499c26ecf88ae75Eli Friedman} 10856b3014b07c40a6ed8b0c8ed63950df02eeb82c28Eli Friedman 10866b3014b07c40a6ed8b0c8ed63950df02eeb82c28Eli Friedmannamespace InstantiateCaseStmt { 10876b3014b07c40a6ed8b0c8ed63950df02eeb82c28Eli Friedman template<int x> constexpr int f() { return x; } 10886b3014b07c40a6ed8b0c8ed63950df02eeb82c28Eli Friedman template<int x> int g(int c) { switch(c) { case f<x>(): return 1; } return 0; } 10896b3014b07c40a6ed8b0c8ed63950df02eeb82c28Eli Friedman int gg(int c) { return g<4>(c); } 10906b3014b07c40a6ed8b0c8ed63950df02eeb82c28Eli Friedman} 1091495f42a32610c03591b49cd06ac09c5408742f86Richard Smith 1092495f42a32610c03591b49cd06ac09c5408742f86Richard Smithnamespace ConvertedConstantExpr { 1093495f42a32610c03591b49cd06ac09c5408742f86Richard Smith extern int &m; 1094495f42a32610c03591b49cd06ac09c5408742f86Richard Smith extern int &n; 1095495f42a32610c03591b49cd06ac09c5408742f86Richard Smith 1096495f42a32610c03591b49cd06ac09c5408742f86Richard Smith constexpr int k = 4; 1097495f42a32610c03591b49cd06ac09c5408742f86Richard Smith int &m = const_cast<int&>(k); 1098495f42a32610c03591b49cd06ac09c5408742f86Richard Smith 1099495f42a32610c03591b49cd06ac09c5408742f86Richard Smith // If we have nothing more interesting to say, ensure we don't produce a 1100495f42a32610c03591b49cd06ac09c5408742f86Richard Smith // useless note and instead just point to the non-constant subexpression. 1101495f42a32610c03591b49cd06ac09c5408742f86Richard Smith enum class E { 1102495f42a32610c03591b49cd06ac09c5408742f86Richard Smith em = m, 1103495f42a32610c03591b49cd06ac09c5408742f86Richard Smith en = n, // expected-error {{not a constant expression}} 1104495f42a32610c03591b49cd06ac09c5408742f86Richard Smith eo = (m + 1105495f42a32610c03591b49cd06ac09c5408742f86Richard Smith n // expected-error {{not a constant expression}} 1106495f42a32610c03591b49cd06ac09c5408742f86Richard Smith ), 1107495f42a32610c03591b49cd06ac09c5408742f86Richard Smith eq = reinterpret_cast<int>((int*)0) // expected-error {{not a constant expression}} expected-note {{reinterpret_cast}} 1108495f42a32610c03591b49cd06ac09c5408742f86Richard Smith }; 1109495f42a32610c03591b49cd06ac09c5408742f86Richard Smith} 1110d9b02e726262e4009dda830998bb934172ac0020Richard Smith 1111d9b02e726262e4009dda830998bb934172ac0020Richard Smithnamespace IndirectField { 1112d9b02e726262e4009dda830998bb934172ac0020Richard Smith struct S { 1113d9b02e726262e4009dda830998bb934172ac0020Richard Smith struct { // expected-warning {{GNU extension}} 1114d9b02e726262e4009dda830998bb934172ac0020Richard Smith union { 1115d9b02e726262e4009dda830998bb934172ac0020Richard Smith struct { // expected-warning {{GNU extension}} 1116d9b02e726262e4009dda830998bb934172ac0020Richard Smith int a; 1117d9b02e726262e4009dda830998bb934172ac0020Richard Smith int b; 1118d9b02e726262e4009dda830998bb934172ac0020Richard Smith }; 1119d9b02e726262e4009dda830998bb934172ac0020Richard Smith int c; 1120d9b02e726262e4009dda830998bb934172ac0020Richard Smith }; 1121d9b02e726262e4009dda830998bb934172ac0020Richard Smith int d; 1122d9b02e726262e4009dda830998bb934172ac0020Richard Smith }; 1123d9b02e726262e4009dda830998bb934172ac0020Richard Smith union { 1124d9b02e726262e4009dda830998bb934172ac0020Richard Smith int e; 1125d9b02e726262e4009dda830998bb934172ac0020Richard Smith int f; 1126d9b02e726262e4009dda830998bb934172ac0020Richard Smith }; 1127d9b02e726262e4009dda830998bb934172ac0020Richard Smith constexpr S(int a, int b, int d, int e) : a(a), b(b), d(d), e(e) {} 1128d9b02e726262e4009dda830998bb934172ac0020Richard Smith constexpr S(int c, int d, int f) : c(c), d(d), f(f) {} 1129d9b02e726262e4009dda830998bb934172ac0020Richard Smith }; 1130d9b02e726262e4009dda830998bb934172ac0020Richard Smith 1131d9b02e726262e4009dda830998bb934172ac0020Richard Smith constexpr S s1(1, 2, 3, 4); 1132d9b02e726262e4009dda830998bb934172ac0020Richard Smith constexpr S s2(5, 6, 7); 1133d9b02e726262e4009dda830998bb934172ac0020Richard Smith 1134d9b02e726262e4009dda830998bb934172ac0020Richard Smith // FIXME: The diagnostics here do a very poor job of explaining which unnamed 1135d9b02e726262e4009dda830998bb934172ac0020Richard Smith // member is active and which is requested. 1136d9b02e726262e4009dda830998bb934172ac0020Richard Smith static_assert(s1.a == 1, ""); 1137d9b02e726262e4009dda830998bb934172ac0020Richard Smith static_assert(s1.b == 2, ""); 1138d9b02e726262e4009dda830998bb934172ac0020Richard Smith static_assert(s1.c == 0, ""); // expected-error {{constant expression}} expected-note {{union with active member}} 1139d9b02e726262e4009dda830998bb934172ac0020Richard Smith static_assert(s1.d == 3, ""); 1140d9b02e726262e4009dda830998bb934172ac0020Richard Smith static_assert(s1.e == 4, ""); 1141d9b02e726262e4009dda830998bb934172ac0020Richard Smith static_assert(s1.f == 0, ""); // expected-error {{constant expression}} expected-note {{union with active member}} 1142d9b02e726262e4009dda830998bb934172ac0020Richard Smith 1143d9b02e726262e4009dda830998bb934172ac0020Richard Smith static_assert(s2.a == 0, ""); // expected-error {{constant expression}} expected-note {{union with active member}} 1144d9b02e726262e4009dda830998bb934172ac0020Richard Smith static_assert(s2.b == 0, ""); // expected-error {{constant expression}} expected-note {{union with active member}} 1145d9b02e726262e4009dda830998bb934172ac0020Richard Smith static_assert(s2.c == 5, ""); 1146d9b02e726262e4009dda830998bb934172ac0020Richard Smith static_assert(s2.d == 6, ""); 1147d9b02e726262e4009dda830998bb934172ac0020Richard Smith static_assert(s2.e == 0, ""); // expected-error {{constant expression}} expected-note {{union with active member}} 1148d9b02e726262e4009dda830998bb934172ac0020Richard Smith static_assert(s2.f == 7, ""); 1149d9b02e726262e4009dda830998bb934172ac0020Richard Smith} 1150f15fda02e9c8c82b4a716618f4010b9af8bff796Richard Smith 1151b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith// DR1405: don't allow reading mutable members in constant expressions. 1152b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smithnamespace MutableMembers { 1153b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith struct MM { 1154b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith mutable int n; // expected-note 3{{declared here}} 1155b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith } constexpr mm = { 4 }; 1156b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith constexpr int mmn = mm.n; // expected-error {{constant expression}} expected-note {{read of mutable member 'n' is not allowed in a constant expression}} 1157b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith int x = (mm.n = 1, 3); 1158b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith constexpr int mmn2 = mm.n; // expected-error {{constant expression}} expected-note {{read of mutable member 'n' is not allowed in a constant expression}} 1159b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith 1160b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith // Here's one reason why allowing this would be a disaster... 1161b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith template<int n> struct Id { int k = n; }; 1162b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith int f() { 1163b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith constexpr MM m = { 0 }; 1164b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith ++m.n; 1165b4e5e286a5cd156247720b1eb204abaa8e09568dRichard 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}} 1166b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith } 1167b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith 1168b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith struct A { int n; }; 1169b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith struct B { mutable A a; }; // expected-note {{here}} 1170b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith struct C { B b; }; 1171b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith constexpr C c[3] = {}; 1172b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith constexpr int k = c[1].b.a.n; // expected-error {{constant expression}} expected-note {{mutable}} 1173b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith} 1174b4e5e286a5cd156247720b1eb204abaa8e09568dRichard Smith 1175f15fda02e9c8c82b4a716618f4010b9af8bff796Richard Smithnamespace Fold { 1176f15fda02e9c8c82b4a716618f4010b9af8bff796Richard Smith 1177f15fda02e9c8c82b4a716618f4010b9af8bff796Richard Smith // This macro forces its argument to be constant-folded, even if it's not 1178f15fda02e9c8c82b4a716618f4010b9af8bff796Richard Smith // otherwise a constant expression. 1179f15fda02e9c8c82b4a716618f4010b9af8bff796Richard Smith #define fold(x) (__builtin_constant_p(x) ? (x) : (x)) 1180f15fda02e9c8c82b4a716618f4010b9af8bff796Richard Smith 1181f15fda02e9c8c82b4a716618f4010b9af8bff796Richard Smith constexpr int n = (int)(char*)123; // expected-error {{constant expression}} expected-note {{reinterpret_cast}} 1182f15fda02e9c8c82b4a716618f4010b9af8bff796Richard Smith constexpr int m = fold((int)(char*)123); // ok 1183f15fda02e9c8c82b4a716618f4010b9af8bff796Richard Smith static_assert(m == 123, ""); 1184f15fda02e9c8c82b4a716618f4010b9af8bff796Richard Smith 1185f15fda02e9c8c82b4a716618f4010b9af8bff796Richard Smith #undef fold 1186f15fda02e9c8c82b4a716618f4010b9af8bff796Richard Smith 1187f15fda02e9c8c82b4a716618f4010b9af8bff796Richard Smith} 118883587db1bda97f45d2b5a4189e584e2a18be511aRichard Smith 118983587db1bda97f45d2b5a4189e584e2a18be511aRichard Smithnamespace DR1454 { 119083587db1bda97f45d2b5a4189e584e2a18be511aRichard Smith 119183587db1bda97f45d2b5a4189e584e2a18be511aRichard Smithconstexpr const int &f(const int &n) { return n; } 119283587db1bda97f45d2b5a4189e584e2a18be511aRichard Smithconstexpr int k1 = f(0); // ok 119383587db1bda97f45d2b5a4189e584e2a18be511aRichard Smith 119483587db1bda97f45d2b5a4189e584e2a18be511aRichard Smithstruct Wrap { 119583587db1bda97f45d2b5a4189e584e2a18be511aRichard Smith const int &value; 119683587db1bda97f45d2b5a4189e584e2a18be511aRichard Smith}; 119783587db1bda97f45d2b5a4189e584e2a18be511aRichard Smithconstexpr const Wrap &g(const Wrap &w) { return w; } 119883587db1bda97f45d2b5a4189e584e2a18be511aRichard Smithconstexpr int k2 = g({0}).value; // ok 119983587db1bda97f45d2b5a4189e584e2a18be511aRichard Smith 120083587db1bda97f45d2b5a4189e584e2a18be511aRichard Smithconstexpr const int &i = 0; // expected-error {{constant expression}} expected-note {{temporary}} expected-note 2{{here}} 120183587db1bda97f45d2b5a4189e584e2a18be511aRichard Smithconstexpr const int j = i; // expected-error {{constant expression}} expected-note {{initializer of 'i' is not a constant expression}} 120283587db1bda97f45d2b5a4189e584e2a18be511aRichard Smith 120383587db1bda97f45d2b5a4189e584e2a18be511aRichard Smith} 120474e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith 120574e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smithnamespace RecursiveOpaqueExpr { 120674e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith template<typename Iter> 120774e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith constexpr auto LastNonzero(Iter p, Iter q) -> decltype(+*p) { 120874e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith return p != q ? (LastNonzero(p+1, q) ?: *p) : 0; // expected-warning {{GNU}} 120974e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith } 121074e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith 121174e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith constexpr int arr1[] = { 1, 0, 0, 3, 0, 2, 0, 4, 0, 0 }; 121274e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith static_assert(LastNonzero(begin(arr1), end(arr1)) == 4, ""); 121374e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith 121474e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith constexpr int arr2[] = { 1, 0, 0, 3, 0, 2, 0, 4, 0, 5 }; 121574e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith static_assert(LastNonzero(begin(arr2), end(arr2)) == 5, ""); 121674e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith} 121774e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith 121874e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smithnamespace VLASizeof { 121974e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith 122074e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith void f(int k) { 122174e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith int arr[k]; // expected-warning {{C99}} 122274e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith constexpr int n = 1 + 122374e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith sizeof(arr) // expected-error {{constant expression}} 122474e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith * 3; 122574e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith } 122674e1ad93fa8d6347549bcb10279fdf1fbc775321Richard Smith} 1227b78ae9716576399145786b93f687943f8b197170Richard Smith 1228b78ae9716576399145786b93f687943f8b197170Richard Smithnamespace CompoundLiteral { 1229b78ae9716576399145786b93f687943f8b197170Richard Smith // FIXME: 1230b78ae9716576399145786b93f687943f8b197170Richard Smith // We don't model the semantics of this correctly: the compound literal is 1231b78ae9716576399145786b93f687943f8b197170Richard Smith // represented as a prvalue in the AST, but actually behaves like an lvalue. 1232b78ae9716576399145786b93f687943f8b197170Richard Smith // We treat the compound literal as a temporary and refuse to produce a 1233b78ae9716576399145786b93f687943f8b197170Richard Smith // pointer to it. This is OK: we're not required to treat this as a constant 1234b78ae9716576399145786b93f687943f8b197170Richard Smith // in C++, and in C we model compound literals as lvalues. 1235b78ae9716576399145786b93f687943f8b197170Richard Smith constexpr int *p = (int*)(int[1]){0}; // expected-warning {{C99}} expected-error {{constant expression}} expected-note 2{{temporary}} 1236b78ae9716576399145786b93f687943f8b197170Richard Smith} 12374b1f684416980ef6f1a7cb9e6af9c4fa4a164617Richard Smith 12384b1f684416980ef6f1a7cb9e6af9c4fa4a164617Richard Smithnamespace Vector { 12394b1f684416980ef6f1a7cb9e6af9c4fa4a164617Richard Smith typedef int __attribute__((vector_size(16))) VI4; 12404b1f684416980ef6f1a7cb9e6af9c4fa4a164617Richard Smith constexpr VI4 f(int n) { 12414b1f684416980ef6f1a7cb9e6af9c4fa4a164617Richard Smith return VI4 { n * 3, n + 4, n - 5, n / 6 }; 12424b1f684416980ef6f1a7cb9e6af9c4fa4a164617Richard Smith } 12434b1f684416980ef6f1a7cb9e6af9c4fa4a164617Richard Smith constexpr auto v1 = f(10); 12444b1f684416980ef6f1a7cb9e6af9c4fa4a164617Richard Smith 12454b1f684416980ef6f1a7cb9e6af9c4fa4a164617Richard Smith typedef double __attribute__((vector_size(32))) VD4; 12464b1f684416980ef6f1a7cb9e6af9c4fa4a164617Richard Smith constexpr VD4 g(int n) { 12474b1f684416980ef6f1a7cb9e6af9c4fa4a164617Richard Smith return (VD4) { n / 2.0, n + 1.5, n - 5.4, n * 0.9 }; // expected-warning {{C99}} 12484b1f684416980ef6f1a7cb9e6af9c4fa4a164617Richard Smith } 12494b1f684416980ef6f1a7cb9e6af9c4fa4a164617Richard Smith constexpr auto v2 = g(4); 12504b1f684416980ef6f1a7cb9e6af9c4fa4a164617Richard Smith} 1251