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// RUN: %clang_cc1 -std=c11 -fsyntax-only -verify -Wunused-value -Wunused-label %s
// RUN: %clang_cc1 -std=c11 -fsyntax-only -verify -Wunused %s
// RUN: %clang_cc1 -std=c11 -fsyntax-only -verify -Wall %s
int i = 0;
int j = 0;
void foo();
// PR4806
void pr4806() {
1,foo(); // expected-warning {{expression result unused}}
// other
foo();
i; // expected-warning {{expression result unused}}
i,foo(); // expected-warning {{expression result unused}}
foo(),i; // expected-warning {{expression result unused}}
i,j,foo(); // expected-warning {{expression result unused}} expected-warning {{expression result unused}}
i,foo(),j; // expected-warning {{expression result unused}} expected-warning {{expression result unused}}
foo(),i,j; // expected-warning {{expression result unused}} expected-warning {{expression result unused}}
i++;
i++,foo();
foo(),i++;
i++,j,foo(); // expected-warning {{expression result unused}}
i++,foo(),j; // expected-warning {{expression result unused}}
foo(),i++,j; // expected-warning {{expression result unused}}
i,j++,foo(); // expected-warning {{expression result unused}}
i,foo(),j++; // expected-warning {{expression result unused}}
foo(),i,j++; // expected-warning {{expression result unused}}
i++,j++,foo();
i++,foo(),j++;
foo(),i++,j++;
{};
({});
({}),foo();
foo(),({});
(int)1U; // expected-warning {{expression result unused}}
(void)1U;
// pointer to volatile has side effect (thus no warning)
int* pi = &i;
volatile int* pj = &j;
*pi; // expected-warning {{expression result unused}}
*pj;
foo_label: // expected-warning {{unused label}}
i; // expected-warning {{expression result unused}}
}
// Don't warn about unused '||', '&&' expressions that contain assignments.
int test_logical_foo1();
int test_logical_foo2();
int test_logical_foo3();
int test_logical_bar() {
int x = 0;
(x = test_logical_foo1()) || // no-warning
(x = test_logical_foo2()) || // no-warning
(x = test_logical_foo3()); // no-warning
x || test_logical_foo1(); // no-warning
return x;
}
// PR8282
void conditional_for_control_flow(int cond, int x, int y)
{
cond? y++ : x; // no-warning
cond? y : ++x; // no-warning
cond? (x |= y) : ++x; // no-warning
cond? y : x; // expected-warning {{expression result unused}}
}
struct s0 { int f0; };
void f0(int a);
void f1(struct s0 *a) {
// rdar://8139785
f0((int)(a->f0 + 1, 10)); // expected-warning {{expression result unused}}
}
void blah(int a);
#define GenTest(x) _Generic(x, default : blah)(x)
void unevaluated_operands(void) {
int val = 0;
(void)sizeof(++val); // expected-warning {{expression with side effects has no effect in an unevaluated context}}
(void)_Generic(val++, default : 0); // expected-warning {{expression with side effects has no effect in an unevaluated context}}
(void)_Alignof(val++); // expected-warning {{expression with side effects has no effect in an unevaluated context}} expected-warning {{'_Alignof' applied to an expression is a GNU extension}}
// VLAs can have side effects so long as it's part of the type and not
// an expression.
(void)sizeof(int[++val]); // Ok
(void)_Alignof(int[++val]); // Ok
// Side effects as part of macro expansion are ok.
GenTest(val++);
}
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