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// RUN: %clang_cc1 -fsyntax-only -verify %s -std=c++2a
int foo(int x) {
return x == x; // expected-warning {{self-comparison always evaluates to true}}
}
struct X {
bool operator==(const X &x);
};
struct A {
int x;
X x2;
int a[3];
int b[3];
bool f() { return x == x; } // expected-warning {{self-comparison always evaluates to true}}
bool g() { return x2 == x2; } // no-warning
bool h() { return a == b; } // expected-warning {{array comparison always evaluates to false}}
bool i() {
int c[3];
return a == c; // expected-warning {{array comparison always evaluates to false}}
}
};
namespace NA { extern "C" int x[3]; }
namespace NB { extern "C" int x[3]; }
bool k = NA::x == NB::x; // expected-warning {{self-comparison always evaluates to true}}
template<typename T> struct Y { static inline int n; };
bool f() {
return
Y<int>::n == Y<int>::n || // expected-warning {{self-comparison always evaluates to true}}
Y<void>::n == Y<int>::n;
}
template<typename T, typename U>
bool g() {
// FIXME: Ideally we'd produce a self-comparison warning on the first of these.
return
Y<T>::n == Y<T>::n ||
Y<T>::n == Y<U>::n;
}
template bool g<int, int>(); // should not produce any warnings
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