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// RUN: %clang_cc1 -fsyntax-only -verify -std=c++20 %s
// RUN: %clang_cc1 -fsyntax-only -verify -std=c++23 %s
consteval int undefined(); // expected-note 2 {{declared here}}
void check_lambdas_unused(
int a = [](int no_error = undefined()) {
return no_error;
}(0),
int b = [](int defaulted = undefined()) {
return defaulted;
}()
) {}
int check_lambdas_used(
int b = [](int no_error = undefined()) {
return no_error;
}(0),
int c = [](int defaulted = undefined()) { // expected-error {{not a constant expression}} \
// expected-note {{declared here}} \
// expected-note {{undefined function 'undefined'}}
return defaulted;
}(), // expected-note {{in the default initializer of 'defaulted'}}
int d = [](int defaulted = sizeof(undefined())) {
return defaulted;
}()
) {
return 0;
}
int test_check_lambdas_used = check_lambdas_used();
struct UnusedInitWithLambda {
int a = [] {
return undefined(); // never evaluated because immediate escalating
}();
// UnusedInitWithLambda is never constructed, so the initializer
// of b and undefined() are never evaluated.
int b = [](int no_error = undefined()) {
return no_error;
}();
};
consteval int ub(int n) {
return 0/n;
}
struct InitWithLambda { // expected-note {{'InitWithLambda' is an immediate constructor because the default initializer of 'b' contains a call to a consteval function 'undefined' and that call is not a constant expression}}
int b = [](int error = undefined()) { // expected-note {{undefined function 'undefined' cannot be used in a constant expression}}
return error;
}();
int c = [](int error = sizeof(undefined()) + ub(0)) {
return error;
}();
} i;
// expected-error@-1 {{call to immediate function 'InitWithLambda::InitWithLambda' is not a constant expression}} \
expected-note@-1 {{in call to 'InitWithLambda()'}}
namespace ShouldNotCrash {
template<typename T>
struct F {
template<typename U>
F(const U&) {}
};
struct A {
static constexpr auto x = [] {};
F<int> f = x;
};
void f(A a = A()) { }
}
namespace GH62224 {
consteval int fwd();
template <int i = fwd()>
struct C {
consteval C(int = fwd()) { }
consteval int get() { return i; }
};
consteval int fwd() { return 42; }
C<> Val; // No error since fwd is defined already.
static_assert(Val.get() == 42);
}
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