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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}}
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