2014-03-15 09:26:32 +08:00
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// RUN: %clang_cc1 %s -fsyntax-only -verify -fblocks -Wunreachable-code-aggressive -Wno-unused-value -Wno-covered-switch-default -I %S/Inputs
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2014-02-22 05:41:23 +08:00
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#include "warn-unreachable.h"
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2010-01-15 11:15:36 +08:00
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2010-09-03 08:25:02 +08:00
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int halt() __attribute__((noreturn));
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2010-01-16 07:17:13 +08:00
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int live();
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int dead();
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2010-01-15 11:15:36 +08:00
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void test1() {
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goto c;
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d:
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goto e; // expected-warning {{will never be executed}}
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c: ;
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int i;
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return;
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goto b; // expected-warning {{will never be executed}}
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goto a; // expected-warning {{will never be executed}}
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b:
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i = 1;
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a:
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i = 2;
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goto f;
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e:
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goto d;
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f: ;
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}
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2010-01-16 07:17:13 +08:00
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void test2() {
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2010-01-22 01:31:41 +08:00
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int i;
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2010-01-16 07:17:13 +08:00
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switch (live()) {
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case 1:
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halt(),
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dead(); // expected-warning {{will never be executed}}
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case 2:
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2010-01-22 01:21:23 +08:00
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live(), halt(),
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2010-01-16 07:17:13 +08:00
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dead(); // expected-warning {{will never be executed}}
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case 3:
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2010-10-24 16:21:40 +08:00
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live()
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+ // expected-warning {{will never be executed}}
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2010-01-22 01:21:23 +08:00
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halt();
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dead();
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2010-01-16 07:17:13 +08:00
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case 4:
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a4:
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live(),
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halt();
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goto a4; // expected-warning {{will never be executed}}
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case 5:
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goto a5;
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c5:
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dead(); // expected-warning {{will never be executed}}
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goto b5;
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a5:
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live(),
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halt();
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b5:
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goto c5;
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case 6:
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if (live())
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goto e6;
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live(),
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halt();
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d6:
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dead(); // expected-warning {{will never be executed}}
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goto b6;
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c6:
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dead();
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goto b6;
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e6:
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live(),
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halt();
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b6:
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goto c6;
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2010-01-22 01:21:23 +08:00
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case 7:
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halt()
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2010-10-24 16:21:40 +08:00
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+
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dead(); // expected-warning {{will never be executed}}
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2010-01-22 01:21:23 +08:00
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- // expected-warning {{will never be executed}}
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halt();
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2010-01-22 01:31:41 +08:00
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case 8:
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2013-02-06 06:00:19 +08:00
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i
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+= // expected-warning {{will never be executed}}
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2010-01-22 01:31:41 +08:00
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halt();
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2010-01-22 03:44:04 +08:00
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case 9:
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halt()
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? // expected-warning {{will never be executed}}
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dead() : dead();
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2010-01-22 03:51:34 +08:00
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case 10:
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( // expected-warning {{will never be executed}}
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float)halt();
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2010-01-22 07:15:53 +08:00
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case 11: {
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int a[5];
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live(),
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2013-02-06 06:00:19 +08:00
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a[halt()
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]; // expected-warning {{will never be executed}}
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2010-01-22 07:15:53 +08:00
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}
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2010-01-16 07:17:13 +08:00
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}
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}
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2010-09-09 08:06:10 +08:00
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enum Cases { C1, C2, C3 };
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int test_enum_cases(enum Cases C) {
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switch (C) {
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case C1:
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case C2:
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case C3:
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return 1;
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default: {
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2014-02-27 13:42:07 +08:00
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int i = 0; // no-warning
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2010-09-09 08:06:10 +08:00
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++i;
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return i;
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}
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}
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}
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2011-08-26 03:28:55 +08:00
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// Handle unreachable code triggered by macro expansions.
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void __myassert_rtn(const char *, const char *, int, const char *) __attribute__((__noreturn__));
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#define myassert(e) \
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(__builtin_expect(!(e), 0) ? __myassert_rtn(__func__, __FILE__, __LINE__, #e) : (void)0)
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void test_assert() {
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myassert(0 && "unreachable");
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return; // no-warning
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}
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2012-01-04 05:02:04 +08:00
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// Test case for PR 9774. Tests that dead code in macros aren't warned about.
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#define MY_MAX(a,b) ((a) >= (b) ? (a) : (b))
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void PR9774(int *s) {
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for (int i = 0; i < MY_MAX(2, 3); i++) // no-warning
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s[i] = 0;
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}
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2011-08-26 03:28:55 +08:00
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2012-08-24 15:42:09 +08:00
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// Test case for <rdar://problem/11005770>. We should treat code guarded
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// by 'x & 0' and 'x * 0' as unreachable.
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2014-03-05 08:01:17 +08:00
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int calledFun();
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2012-08-24 15:42:09 +08:00
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void test_mul_and_zero(int x) {
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if (x & 0) calledFun(); // expected-warning {{will never be executed}}
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if (0 & x) calledFun(); // expected-warning {{will never be executed}}
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if (x * 0) calledFun(); // expected-warning {{will never be executed}}
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if (0 * x) calledFun(); // expected-warning {{will never be executed}}
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}
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2014-02-27 08:24:08 +08:00
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void raze() __attribute__((noreturn));
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void warn_here();
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int test_break_preceded_by_noreturn(int i) {
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switch (i) {
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case 1:
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raze();
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2014-03-15 13:47:06 +08:00
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break; // expected-warning {{'break' will never be executed}}
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2014-02-27 08:24:08 +08:00
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case 2:
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raze();
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2014-03-15 13:47:06 +08:00
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break; // expected-warning {{'break' will never be executed}}
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2014-02-27 08:24:08 +08:00
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warn_here(); // expected-warning {{will never be executed}}
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case 3:
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return 1;
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break; // expected-warning {{will never be executed}}
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default:
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break;
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2014-03-06 07:38:43 +08:00
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break; // expected-warning {{will never be executed}}
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2014-02-27 08:24:08 +08:00
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}
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return i;
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}
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2014-02-27 13:42:07 +08:00
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// Don't warn about unreachable 'default' cases, as that is covered
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// by -Wcovered-switch-default.
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typedef enum { Value1 = 1 } MyEnum;
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void unreachable_default(MyEnum e) {
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switch (e) {
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2014-02-27 14:32:28 +08:00
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case Value1:
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2014-02-27 13:42:07 +08:00
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calledFun();
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break;
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2014-02-28 05:56:47 +08:00
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case 2: // expected-warning {{case value not in enumerated type 'MyEnum'}}
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calledFun();
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break;
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2014-02-27 13:42:07 +08:00
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default:
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calledFun(); // no-warning
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break;
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}
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}
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void unreachable_in_default(MyEnum e) {
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switch (e) {
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default:
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raze();
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calledFun(); // expected-warning {{will never be executed}}
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break;
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}
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}
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2014-02-27 14:32:32 +08:00
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// Don't warn about trivial dead returns.
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int trivial_dead_return() {
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raze();
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2014-03-15 13:47:06 +08:00
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return ((0)); // expected-warning {{'return' will never be executed}}
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2014-02-27 14:32:32 +08:00
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}
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2014-03-08 10:22:23 +08:00
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void trivial_dead_return_void() {
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raze();
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2014-03-15 13:47:06 +08:00
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return; // expected-warning {{'return' will never be executed}}
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2014-03-08 10:22:23 +08:00
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}
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2014-02-27 14:32:32 +08:00
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MyEnum trival_dead_return_enum() {
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raze();
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2014-03-15 13:47:06 +08:00
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return Value1; // expected-warning {{'return' will never be executed}}
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2014-02-27 14:32:32 +08:00
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}
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2014-03-06 07:46:07 +08:00
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MyEnum trivial_dead_return_enum_2(int x) {
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switch (x) {
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case 1: return 1;
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case 2: return 2;
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case 3: return 3;
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2014-03-06 09:09:45 +08:00
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default: return 4;
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2014-03-06 07:46:07 +08:00
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}
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2014-03-06 09:09:45 +08:00
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return 2; // expected-warning {{will never be executed}}
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2014-03-06 07:46:07 +08:00
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}
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2014-03-07 10:25:50 +08:00
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const char *trivial_dead_return_cstr() {
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raze();
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2014-03-15 13:47:06 +08:00
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return ""; // expected-warning {{return' will never be executed}}
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2014-03-07 10:25:50 +08:00
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}
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char trivial_dead_return_char() {
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raze();
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2014-03-15 13:47:06 +08:00
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return ' '; // expected-warning {{return' will never be executed}}
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2014-03-07 10:25:50 +08:00
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}
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2014-03-06 07:46:07 +08:00
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MyEnum nontrivial_dead_return_enum_2(int x) {
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switch (x) {
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case 1: return 1;
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case 2: return 2;
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case 3: return 3;
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default: return 4;
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}
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return calledFun(); // expected-warning {{will never be executed}}
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}
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2014-03-06 16:09:00 +08:00
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enum X { A, B, C };
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int covered_switch(enum X x) {
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switch (x) {
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case A: return 1;
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case B: return 2;
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case C: return 3;
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}
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return 4; // no-warning
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}
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2014-03-05 08:01:17 +08:00
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// Test unreachable code depending on configuration values
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#define CONFIG_CONSTANT 1
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int test_config_constant(int x) {
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if (!CONFIG_CONSTANT) {
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calledFun(); // no-warning
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return 1;
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}
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2014-03-29 08:35:20 +08:00
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if (!1) { // expected-note {{silence by adding parentheses to mark code as explicitly dead}}
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2014-03-05 08:01:17 +08:00
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calledFun(); // expected-warning {{will never be executed}}
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return 1;
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}
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if (sizeof(int) > sizeof(char)) {
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calledFun(); // no-warning
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return 1;
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}
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if (x > 10)
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return CONFIG_CONSTANT ? calledFun() : calledFun(); // no-warning
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else
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2014-03-29 08:35:20 +08:00
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return 1 ? // expected-note {{silence by adding parentheses to mark code as explicitly dead}}
|
2014-03-05 08:01:17 +08:00
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calledFun() :
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calledFun(); // expected-warning {{will never be executed}}
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}
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2014-03-07 10:25:50 +08:00
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int sizeof_int(int x, int y) {
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2014-03-06 06:32:39 +08:00
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if (sizeof(long) == sizeof(int))
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return 1; // no-warning
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if (sizeof(long) != sizeof(int))
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return 0; // no-warning
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2014-03-07 10:25:53 +08:00
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if (x && y && sizeof(long) < sizeof(char))
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return 0; // no-warning
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2014-03-06 06:32:39 +08:00
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return 2; // no-warning
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}
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2014-03-06 07:46:07 +08:00
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enum MyEnum2 {
|
2014-03-06 07:38:41 +08:00
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ME_A = CONFIG_CONSTANT,
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ME_B = 1
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};
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int test_MyEnum() {
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if (!ME_A)
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return 1; // no-warning
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if (ME_A)
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return 2; // no-warning
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if (ME_B)
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return 3;
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if (!ME_B) // expected-warning {{will never be executed}}
|
2014-03-06 08:17:44 +08:00
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|
return 4; // expected-warning {{will never be executed}}
|
2014-03-06 07:38:41 +08:00
|
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|
return 5;
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|
}
|
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|
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|
2014-03-06 08:17:44 +08:00
|
|
|
// Test for idiomatic do..while.
|
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|
int test_do_while(int x) {
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do {
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|
|
if (x == calledFun())
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break;
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++x;
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break;
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}
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while (0); // no-warning
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|
return x;
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|
}
|
|
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|
int test_do_while_nontrivial_cond(int x) {
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|
|
|
do {
|
|
|
|
if (x == calledFun())
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|
break;
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|
++x;
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|
break;
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|
}
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|
|
while (calledFun()); // expected-warning {{will never be executed}}
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|
return x;
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|
|
}
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|
|
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|
2014-03-15 13:47:06 +08:00
|
|
|
// Diagnostic control: -Wunreachable-code-return.
|
|
|
|
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|
|
#pragma clang diagnostic push
|
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|
|
#pragma clang diagnostic ignored "-Wunreachable-code-return"
|
|
|
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|
void trivial_dead_return_void_SUPPRESSED() {
|
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|
|
raze();
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|
return; // no-warning
|
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|
|
}
|
|
|
|
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|
|
MyEnum trival_dead_return_enum_SUPPRESSED() {
|
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|
|
raze();
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|
return Value1; // no-warning
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|
|
}
|
|
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|
#pragma clang diagnostic pop
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|
|
// Diagnostic control: -Wunreachable-code-break.
|
|
|
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|
|
#pragma clang diagnostic push
|
|
|
|
#pragma clang diagnostic ignored "-Wunreachable-code-break"
|
|
|
|
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|
|
int test_break_preceded_by_noreturn_SUPPRESSED(int i) {
|
|
|
|
switch (i) {
|
|
|
|
case 1:
|
|
|
|
raze();
|
|
|
|
break; // no-warning
|
|
|
|
case 2:
|
|
|
|
raze();
|
|
|
|
break; // no-warning
|
|
|
|
warn_here(); // expected-warning {{will never be executed}}
|
|
|
|
case 3:
|
|
|
|
return 1;
|
|
|
|
break; // no-warning
|
|
|
|
default:
|
|
|
|
break;
|
|
|
|
break; // no-warning
|
|
|
|
}
|
|
|
|
return i;
|
|
|
|
}
|
|
|
|
|
|
|
|
#pragma clang diagnostic pop
|
2014-03-29 08:35:20 +08:00
|
|
|
|
|
|
|
// Test "silencing" with parentheses.
|
|
|
|
void test_with_paren_silencing(int x) {
|
|
|
|
if (0) calledFun(); // expected-warning {{will never be executed}} expected-note {{silence by adding parentheses to mark code as explicitly dead}}
|
|
|
|
if ((0)) calledFun(); // no-warning
|
|
|
|
|
|
|
|
if (1) // expected-note {{silence by adding parentheses to mark code as explicitly dead}}
|
|
|
|
calledFun();
|
|
|
|
else
|
|
|
|
calledFun(); // expected-warning {{will never be executed}}
|
|
|
|
|
|
|
|
if ((1))
|
|
|
|
calledFun();
|
|
|
|
else
|
|
|
|
calledFun(); // no-warning
|
|
|
|
|
|
|
|
if (!1) // expected-note {{silence by adding parentheses to mark code as explicitly dead}}
|
|
|
|
calledFun(); // expected-warning {{code will never be executed}}
|
|
|
|
else
|
|
|
|
calledFun();
|
|
|
|
|
|
|
|
if ((!1))
|
|
|
|
calledFun(); // no-warning
|
|
|
|
else
|
|
|
|
calledFun();
|
|
|
|
|
|
|
|
if (!(1))
|
|
|
|
calledFun(); // no-warning
|
|
|
|
else
|
|
|
|
calledFun();
|
|
|
|
}
|