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// RUN: %clang_cc1 -fsyntax-only -verify -Wtautological-overlap-compare %s
#define mydefine 2
enum Choices {
CHOICE_0 = 0,
CHOICE_1 = 1
};
enum Unchoices {
UNCHOICE_0 = 0,
UNCHOICE_1 = 1
};
void f(int x) {
int y = 0;
// > || <
if (x > 2 || x < 1) { }
if (x > 2 || x < 2) { }
if (x != 2 || x != 3) { } // expected-warning {{overlapping comparisons always evaluate to true}}
if (x > 2 || x < 3) { } // expected-warning {{overlapping comparisons always evaluate to true}}
if (x > 0 || x < 0) { }
if (x > 2 || x <= 1) { }
if (x > 2 || x <= 2) { } // expected-warning {{overlapping comparisons always evaluate to true}}
if (x > 2 || x <= 3) { } // expected-warning {{overlapping comparisons always evaluate to true}}
if (x >= 2 || x < 1) { }
if (x >= 2 || x < 2) { } // expected-warning {{overlapping comparisons always evaluate to true}}
if (x >= 2 || x < 3) { } // expected-warning {{overlapping comparisons always evaluate to true}}
if (x >= 2 || x <= 1) { } // expected-warning {{overlapping comparisons always evaluate to true}}
if (x >= 2 || x <= 2) { } // expected-warning {{overlapping comparisons always evaluate to true}}
if (x >= 2 || x <= 3) { } // expected-warning {{overlapping comparisons always evaluate to true}}
if (x >= 0 || x <= 0) { } // expected-warning {{overlapping comparisons always evaluate to true}}
// > && <
if (x > 2 && x < 1) { } // expected-warning {{overlapping comparisons always evaluate to false}}
if (x > 2 && x < 2) { } // expected-warning {{overlapping comparisons always evaluate to false}}
if (x > 2 && x < 3) { } // expected-warning {{overlapping comparisons always evaluate to false}}
if (x > 0 && x < 1) { } // expected-warning {{overlapping comparisons always evaluate to false}}
if (x > 2 && x <= 1) { } // expected-warning {{overlapping comparisons always evaluate to false}}
if (x > 2 && x <= 2) { } // expected-warning {{overlapping comparisons always evaluate to false}}
if (x > 2 && x <= 3) { }
if (x >= 2 && x < 1) { } // expected-warning {{overlapping comparisons always evaluate to false}}
if (x >= 2 && x < 2) { } // expected-warning {{overlapping comparisons always evaluate to false}}
if (x >= 2 && x < 3) { }
if (x >= 0 && x < 0) { } // expected-warning {{overlapping comparisons always evaluate to false}}
if (x >= 2 && x <= 1) { } // expected-warning {{overlapping comparisons always evaluate to false}}
if (x >= 2 && x <= 2) { }
if (x >= 2 && x <= 3) { }
// !=, ==, ..
if (x != 2 || x != 3) { } // expected-warning {{overlapping comparisons always evaluate to true}}
if (x != 2 || x < 3) { } // expected-warning {{overlapping comparisons always evaluate to true}}
if (x == 2 && x == 3) { } // expected-warning {{overlapping comparisons always evaluate to false}}
if (x == 2 && x > 3) { } // expected-warning {{overlapping comparisons always evaluate to false}}
if (x == 3 && x < 0) { } // expected-warning {{overlapping comparisons always evaluate to false}}
if (3 == x && x < 0) { } // expected-warning {{overlapping comparisons always evaluate to false}}
if (x == mydefine && x > 3) { }
if (x == (mydefine + 1) && x > 3) { }
if (x != CHOICE_0 || x != CHOICE_1) { } // expected-warning {{overlapping comparisons always evaluate to true}}
if (x == CHOICE_0 && x == CHOICE_1) { } // expected-warning {{overlapping comparisons always evaluate to false}}
// Don't warn if comparing x to different types
if (x == CHOICE_0 && x == 1) { }
if (x != CHOICE_0 || x != 1) { }
// "Different types" includes different enums
if (x == CHOICE_0 && x == UNCHOICE_1) { }
if (x != CHOICE_0 || x != UNCHOICE_1) { }
}
void enums(enum Choices c) {
if (c != CHOICE_0 || c != CHOICE_1) { } // expected-warning {{overlapping comparisons always evaluate to true}}
if (c == CHOICE_0 && c == CHOICE_1) { } // expected-warning {{overlapping comparisons always evaluate to false}}
// Don't warn if comparing x to different types
if (c == CHOICE_0 && c == 1) { }
if (c != CHOICE_0 || c != 1) { }
// "Different types" includes different enums
if (c == CHOICE_0 && c == UNCHOICE_1) { }
if (c != CHOICE_0 || c != UNCHOICE_1) { }
}
// Don't generate a warning here.
void array_out_of_bounds() {
int x;
int buffer[4];
x = (-7 > 0) ? (buffer[-7]) : 0;
}
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