llvm-project/clang/test/SemaCXX/warn-unused-variables.cpp

153 lines
3.0 KiB
C++

// RUN: %clang_cc1 -fsyntax-only -Wunused-variable -Wunused-label -Wno-c++1y-extensions -verify %s
template<typename T> void f() {
T t;
t = 17;
}
// PR5407
struct A { A(); };
struct B { ~B(); };
void f() {
A a;
B b;
}
// PR5531
namespace PR5531 {
struct A {
};
struct B {
B(int);
};
struct C {
~C();
};
void test() {
A();
B(17);
C();
}
}
template<typename T>
struct X0 { };
template<typename T>
void test_dependent_init(T *p) {
X0<int> i(p);
(void)i;
}
void unused_local_static() {
static int x = 0;
static int y = 0; // expected-warning{{unused variable 'y'}}
#pragma unused(x)
}
// PR10168
namespace PR10168 {
// We expect a warning in the definition only for non-dependent variables, and
// a warning in the instantiation only for dependent variables.
template<typename T>
struct S {
void f() {
int a; // expected-warning {{unused variable 'a'}}
T b; // expected-warning 2{{unused variable 'b'}}
}
};
template<typename T>
void f() {
int a; // expected-warning {{unused variable 'a'}}
T b; // expected-warning 2{{unused variable 'b'}}
}
void g() {
S<int>().f(); // expected-note {{here}}
S<char>().f(); // expected-note {{here}}
f<int>(); // expected-note {{here}}
f<char>(); // expected-note {{here}}
}
}
namespace PR11550 {
struct S1 {
S1();
};
S1 makeS1();
void testS1(S1 a) {
// This constructor call can be elided.
S1 x = makeS1(); // expected-warning {{unused variable 'x'}}
// This one cannot, so no warning.
S1 y;
// This call cannot, but the constructor is trivial.
S1 z = a; // expected-warning {{unused variable 'z'}}
}
// The same is true even when we know thet constructor has side effects.
void foo();
struct S2 {
S2() {
foo();
}
};
S2 makeS2();
void testS2(S2 a) {
S2 x = makeS2(); // expected-warning {{unused variable 'x'}}
S2 y;
S2 z = a; // expected-warning {{unused variable 'z'}}
}
// Or when the constructor is not declared by the user.
struct S3 {
S1 m;
};
S3 makeS3();
void testS3(S3 a) {
S3 x = makeS3(); // expected-warning {{unused variable 'x'}}
S3 y;
S3 z = a; // expected-warning {{unused variable 'z'}}
}
}
namespace PR19305 {
template<typename T> int n = 0; // no warning
int a = n<int>;
template<typename T> const int l = 0; // no warning
int b = l<int>;
// PR19558
template<typename T> const int o = 0; // no warning
template<typename T> const int o<T*> = 0; // no warning
int c = o<int*>;
template<> int o<void> = 0; // no warning
int d = o<void>;
// FIXME: It'd be nice to warn here.
template<typename T> int m = 0;
template<typename T> int m<T*> = 0;
template<> const int m<void> = 0; // expected-warning {{unused variable}}
}
namespace ctor_with_cleanups {
struct S1 {
~S1();
};
struct S2 {
S2(const S1&);
};
void func() {
S2 s((S1()));
}
}
#include "Inputs/warn-unused-variables.h"