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-rw-r--r--clang/test/SemaCXX/warn-unused-comparison.cpp94
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diff --git a/clang/test/SemaCXX/warn-unused-comparison.cpp b/clang/test/SemaCXX/warn-unused-comparison.cpp
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+++ b/clang/test/SemaCXX/warn-unused-comparison.cpp
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+// RUN: %clang_cc1 -fsyntax-only -fcxx-exceptions -verify -Wno-unused -Wunused-comparison %s
+
+struct A {
+ bool operator==(const A&);
+ bool operator!=(const A&);
+ A operator|=(const A&);
+ operator bool();
+};
+
+void test() {
+ int x, *p;
+ A a, b;
+
+ x == 7; // expected-warning {{equality comparison result unused}} \
+ // expected-note {{use '=' to turn this equality comparison into an assignment}}
+ x != 7; // expected-warning {{inequality comparison result unused}} \
+ // expected-note {{use '|=' to turn this inequality comparison into an or-assignment}}
+ 7 == x; // expected-warning {{equality comparison result unused}}
+ p == p; // expected-warning {{equality comparison result unused}} \
+ // expected-note {{use '=' to turn this equality comparison into an assignment}} \
+ // expected-warning {{self-comparison always evaluates to true}}
+ a == a; // expected-warning {{equality comparison result unused}} \
+ // expected-note {{use '=' to turn this equality comparison into an assignment}}
+ a == b; // expected-warning {{equality comparison result unused}} \
+ // expected-note {{use '=' to turn this equality comparison into an assignment}}
+ a != b; // expected-warning {{inequality comparison result unused}} \
+ // expected-note {{use '|=' to turn this inequality comparison into an or-assignment}}
+ A() == b; // expected-warning {{equality comparison result unused}}
+ if (42) x == 7; // expected-warning {{equality comparison result unused}} \
+ // expected-note {{use '=' to turn this equality comparison into an assignment}}
+ else if (42) x == 7; // expected-warning {{equality comparison result unused}} \
+ // expected-note {{use '=' to turn this equality comparison into an assignment}}
+ else x == 7; // expected-warning {{equality comparison result unused}} \
+ // expected-note {{use '=' to turn this equality comparison into an assignment}}
+ do x == 7; // expected-warning {{equality comparison result unused}} \
+ // expected-note {{use '=' to turn this equality comparison into an assignment}}
+ while (false);
+ while (false) x == 7; // expected-warning {{equality comparison result unused}} \
+ // expected-note {{use '=' to turn this equality comparison into an assignment}}
+ for (x == 7; // expected-warning {{equality comparison result unused}} \
+ // expected-note {{use '=' to turn this equality comparison into an assignment}}
+ x == 7; // No warning -- result is used
+ x == 7) // expected-warning {{equality comparison result unused}} \
+ // expected-note {{use '=' to turn this equality comparison into an assignment}}
+ x == 7; // expected-warning {{equality comparison result unused}} \
+ // expected-note {{use '=' to turn this equality comparison into an assignment}}
+ switch (42) default: x == 7; // expected-warning {{equality comparison result unused}} \
+ // expected-note {{use '=' to turn this equality comparison into an assignment}}
+ switch (42) case 42: x == 7; // expected-warning {{equality comparison result unused}} \
+ // expected-note {{use '=' to turn this equality comparison into an assignment}}
+ switch (42) {
+ case 1:
+ case 2:
+ default:
+ case 3:
+ case 4:
+ x == 7; // expected-warning {{equality comparison result unused}} \
+ // expected-note {{use '=' to turn this equality comparison into an assignment}}
+ }
+
+ (void)(x == 7);
+ (void)(p == p); // expected-warning {{self-comparison always evaluates to true}}
+ { bool b = x == 7; }
+
+ { bool b = ({ x == 7; // expected-warning {{equality comparison result unused}} \
+ // expected-note {{use '=' to turn this equality comparison into an assignment}}
+ x == 7; }); } // no warning on the second, its result is used!
+
+#define EQ(x,y) (x) == (y)
+ EQ(x, 5);
+#undef EQ
+}
+
+namespace PR10291 {
+ template<typename T>
+ class X
+ {
+ public:
+
+ X() : i(0) { }
+
+ void foo()
+ {
+ throw
+ i == 0u ?
+ 5 : 6;
+ }
+
+ private:
+ int i;
+ };
+
+ X<int> x;
+}