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// RUN: %clang_cc1 -std=c++17 -fexperimental-new-constant-interpreter -verify=expected,both %s
// RUN: %clang_cc1 -std=c++17 -verify=ref,both %s
constexpr bool isEven(int a) {
bool v = false;
switch(a) {
case 2: return true;
case 4: return true;
case 6: return true;
case 8:
case 10:
case 12:
case 14:
case 16:
return true;
case 18:
v = true;
break;
default:
switch(a) {
case 1:
break;
case 3:
return false;
default:
break;
}
}
return v;
}
static_assert(isEven(2), "");
static_assert(isEven(8), "");
static_assert(isEven(10), "");
static_assert(isEven(18), "");
static_assert(!isEven(1), "");
static_assert(!isEven(3), "");
constexpr int withInit() {
switch(int a = 2; a) {
case 1: return -1;
case 2: return 2;
}
return -1;
}
static_assert(withInit() == 2, "");
constexpr int FT(int a) {
int m = 0;
switch(a) {
case 4: m++;
case 3: m++;
case 2: m++;
case 1: m++;
return m;
}
return -1;
}
static_assert(FT(1) == 1, "");
static_assert(FT(4) == 4, "");
static_assert(FT(5) == -1, "");
constexpr int good() { return 1; }
constexpr int test(int val) {
switch (val) {
case good(): return 100;
default: return -1;
}
return 0;
}
static_assert(test(1) == 100, "");
constexpr int bad(int val) { return val / 0; } // both-warning {{division by zero}}
constexpr int another_test(int val) { // both-note {{declared here}}
switch (val) {
case bad(val): return 100; // both-error {{case value is not a constant expression}} \
// both-note {{cannot be used in a constant expression}}
default: return -1;
}
return 0;
}
static_assert(another_test(1) == 100, ""); // both-error {{static assertion failed}} \
// both-note {{evaluates to}}
namespace gnurange {
constexpr int l(int n) {
return n + 1;
}
constexpr int h(int n) {
return 2 * n + 1;
}
constexpr int f(int x) {
const int n = 2;
constexpr struct {
char lo {'a'};
char hi {'z'};
} s;
switch (x) {
case l(n) ... h(n):
return 1;
case -1 ... 1:
return 2;
case 9 ... 14:
return 3;
case 15:
return 4;
case 16 ... 20:
return 5;
case s.lo ... s.hi:
return 6;
default:
return -1;
}
}
static_assert(f(0) == 2);
static_assert(f(2) == -1);
static_assert(f(3) == 1);
static_assert(f(4) == 1);
static_assert(f(5) == 1);
static_assert(f(6) == -1);
static_assert(f(14) == 3);
static_assert(f(15) == 4);
static_assert(f(16) == 5);
static_assert(f(20) == 5);
static_assert(f('d') == 6);
template <int Lo, int Hi>
constexpr bool g(int x) {
switch (x) {
case Lo ... Hi:
break;
default:
return false;
}
return true;
}
static_assert(g<100, 200>(132));
constexpr bool m(int x) {
switch (x) {
case 10 ... 1: // both-warning {{empty case range specified}}
return true;
default:
return false;
}
}
static_assert(m(3)); // both-error {{static assertion failed due to requirement 'm(3)'}}
static_assert(!m(3));
constexpr bool j(int x) { // both-note {{declared here}}
switch (x) {
case bad(x) ... 100: // both-error {{case value is not a constant expression}} \
// both-note {{cannot be used in a constant expression}}
return true;
default:
break;
}
return false;
}
static_assert(j(1)); // both-error {{static assertion failed}}
constexpr bool d(int x) { // both-note {{declared here}}
switch (x) {
case -100 ... bad(x): // both-error {{case value is not a constant expression}} \
// both-note {{cannot be used in a constant expression}}
return true;
default:
break;
}
return false;
}
static_assert(d(1)); // both-error {{static assertion failed}}
constexpr bool s(int x) { // both-note {{declared here}}
switch (x) {
case bad(x) - 100 ... bad(x) + 100: // both-error {{case value is not a constant expression}} \
// both-note {{cannot be used in a constant expression}}
return true;
default:
break;
}
return false;
}
static_assert(s(1)); // both-error {{static assertion failed}}
}
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