llvm-project/clang/test/AST/Interp/floats.cpp

// RUN: %clang_cc1 -fexperimental-new-constant-interpreter -verify %s
// RUN: %clang_cc1 -verify=ref %s

constexpr int i = 2;
constexpr float f = 1.0f;
static_assert(f == 1.0f, "");

constexpr float f2 = 1u * f;
static_assert(f2 == 1.0f, "");

constexpr float f3 = 1.5;
constexpr int i3 = f3;
static_assert(i3 == 1, "");

constexpr bool b3 = f3;
static_assert(b3, "");


static_assert(1.0f + 3u == 4, "");
static_assert(4.0f / 1.0f == 4, "");
static_assert(10.0f * false == 0, "");

constexpr float floats[] = {1.0f, 2.0f, 3.0f, 4.0f};

constexpr float m = 5.0f / 0.0f; // ref-error {{must be initialized by a constant expression}} \
                                 // ref-note {{division by zero}} \
                                 // expected-error {{must be initialized by a constant expression}} \
                                 // expected-note {{division by zero}}

static_assert(~2.0f == 3, ""); // ref-error {{invalid argument type 'float' to unary expression}} \
                               // expected-error {{invalid argument type 'float' to unary expression}}

/// Initialized by a double.
constexpr float df = 0.0;
/// The other way around.
constexpr double fd = 0.0f;

static_assert(0.0f == -0.0f, "");

const int k = 3 * (1.0f / 3.0f);
static_assert(k == 1, "");

constexpr bool b = 1.0;
static_assert(b, "");

constexpr double db = true;
static_assert(db == 1.0, "");

constexpr float fa[] = {1.0f, 2.0, 1, false};
constexpr double da[] = {1.0f, 2.0, 1, false};

constexpr float fm = __FLT_MAX__;
constexpr int someInt = fm; // ref-error {{must be initialized by a constant expression}} \
                            // ref-note {{is outside the range of representable values}} \
                            // expected-error {{must be initialized by a constant expression}} \
                            // expected-note {{is outside the range of representable values}}