1 volatile int x;
2 
3 void __attribute__((noinline)) sink() {
4   x++; //% self.filecheck("bt", "main.cpp", "-implicit-check-not=artificial")
5   // CHECK: frame #0: 0x{{[0-9a-f]+}} a.out`sink() at main.cpp:[[@LINE-1]]:4 [opt]
6   // CHECK-NEXT: frame #1: 0x{{[0-9a-f]+}} a.out`func3{{.*}} [opt] [artificial]
7   // CHECK-NEXT: frame #2: 0x{{[0-9a-f]+}} a.out`func2{{.*}} [opt]
8   // CHECK-NEXT: frame #3: 0x{{[0-9a-f]+}} a.out`func1{{.*}} [opt] [artificial]
9   // CHECK-NEXT: frame #4: 0x{{[0-9a-f]+}} a.out`main{{.*}} [opt]
10 }
11 
12 void __attribute__((noinline)) func3() { sink(); /* tail */ }
13 
14 void __attribute__((disable_tail_calls, noinline)) func2() { func3(); /* regular */ }
15 
16 void __attribute__((noinline)) func1() { func2(); /* tail */ }
17 
18 int __attribute__((disable_tail_calls)) main() {
19   func1(); /* regular */
20   return 0;
21 }
22