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// RUN: %clang %s -fsyntax-only -Xclang -verify -fblocks -Wunreachable-code -Wno-unused-value -Wno-covered-switch-default
int halt() __attribute__((noreturn));
int live();
int dead();
void test1() {
goto c;
d:
goto e; // expected-warning {{will never be executed}}
c: ;
int i;
return;
goto b; // expected-warning {{will never be executed}}
goto a; // expected-warning {{will never be executed}}
b:
i = 1;
a:
i = 2;
goto f;
e:
goto d;
f: ;
}
void test2() {
int i;
switch (live()) {
case 1:
halt(),
dead(); // expected-warning {{will never be executed}}
case 2:
live(), halt(),
dead(); // expected-warning {{will never be executed}}
case 3:
live()
+ // expected-warning {{will never be executed}}
halt();
dead();
case 4:
a4:
live(),
halt();
goto a4; // expected-warning {{will never be executed}}
case 5:
goto a5;
c5:
dead(); // expected-warning {{will never be executed}}
goto b5;
a5:
live(),
halt();
b5:
goto c5;
case 6:
if (live())
goto e6;
live(),
halt();
d6:
dead(); // expected-warning {{will never be executed}}
goto b6;
c6:
dead();
goto b6;
e6:
live(),
halt();
b6:
goto c6;
case 7:
halt()
+
dead(); // expected-warning {{will never be executed}}
- // expected-warning {{will never be executed}}
halt();
case 8:
i
+= // expected-warning {{will never be executed}}
halt();
case 9:
halt()
? // expected-warning {{will never be executed}}
dead() : dead();
case 10:
( // expected-warning {{will never be executed}}
float)halt();
case 11: {
int a[5];
live(),
a[halt()
]; // expected-warning {{will never be executed}}
}
}
}
enum Cases { C1, C2, C3 };
int test_enum_cases(enum Cases C) {
switch (C) {
case C1:
case C2:
case C3:
return 1;
default: {
int i = 0; // expected-warning{{will never be executed}}
++i;
return i;
}
}
}
// Handle unreachable code triggered by macro expansions.
void __myassert_rtn(const char *, const char *, int, const char *) __attribute__((__noreturn__));
#define myassert(e) \
(__builtin_expect(!(e), 0) ? __myassert_rtn(__func__, __FILE__, __LINE__, #e) : (void)0)
void test_assert() {
myassert(0 && "unreachable");
return; // no-warning
}
// Test case for PR 9774. Tests that dead code in macros aren't warned about.
#define MY_MAX(a,b) ((a) >= (b) ? (a) : (b))
void PR9774(int *s) {
for (int i = 0; i < MY_MAX(2, 3); i++) // no-warning
s[i] = 0;
}
// Test case for <rdar://problem/11005770>. We should treat code guarded
// by 'x & 0' and 'x * 0' as unreachable.
void calledFun();
void test_mul_and_zero(int x) {
if (x & 0) calledFun(); // expected-warning {{will never be executed}}
if (0 & x) calledFun(); // expected-warning {{will never be executed}}
if (x * 0) calledFun(); // expected-warning {{will never be executed}}
if (0 * x) calledFun(); // expected-warning {{will never be executed}}
}
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