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// RUN: %clang_cc1 -fsyntax-only -verify -Wtautological-overlap-compare -Wno-enum-compare %s
// RUN: %clang_cc1 -fsyntax-only -verify -Wall -Wno-unused -Wno-loop-analysis -Wno-enum-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 {{non-overlapping comparisons always evaluate to false}}
if (x > 2 && x < 2) { } // expected-warning {{non-overlapping comparisons always evaluate to false}}
if (x > 2 && x < 3) { } // expected-warning {{non-overlapping comparisons always evaluate to false}}
if (x > 0 && x < 1) { } // expected-warning {{non-overlapping comparisons always evaluate to false}}
if (x > 2 && x <= 1) { } // expected-warning {{non-overlapping comparisons always evaluate to false}}
if (x > 2 && x <= 2) { } // expected-warning {{non-overlapping comparisons always evaluate to false}}
if (x > 2 && x <= 3) { }
if (x >= 2 && x < 1) { } // expected-warning {{non-overlapping comparisons always evaluate to false}}
if (x >= 2 && x < 2) { } // expected-warning {{non-overlapping comparisons always evaluate to false}}
if (x >= 2 && x < 3) { }
if (x >= 0 && x < 0) { } // expected-warning {{non-overlapping comparisons always evaluate to false}}
if (x >= 2 && x <= 1) { } // expected-warning {{non-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 {{non-overlapping comparisons always evaluate to false}}
if (x == 2 && x > 3) { } // expected-warning {{non-overlapping comparisons always evaluate to false}}
if (x == 3 && x < 0) { } // expected-warning {{non-overlapping comparisons always evaluate to false}}
if (3 == x && x < 0) { } // expected-warning {{non-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 {{non-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 {{non-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(void) {
int x;
int buffer[4];
x = (-7 > 0) ? (buffer[-7]) : 0;
}
void bool_contexts(int x) {
if (x > 4 || x < 10) {}
// expected-warning@-1{{overlapping comparisons always evaluate to true}}
for (;x > 4 || x < 10;) {}
// expected-warning@-1{{overlapping comparisons always evaluate to true}}
while (x > 4 || x < 10) {}
// expected-warning@-1{{overlapping comparisons always evaluate to true}}
do {} while (x > 4 || x < 10);
// expected-warning@-1{{overlapping comparisons always evaluate to true}}
x = (x > 4 || x < 10) ? 1 : 2;
// expected-warning@-1{{overlapping comparisons always evaluate to true}}
if ((void)5, x > 4 || x < 10) {}
// expected-warning@-1{{overlapping comparisons always evaluate to true}}
}
void assignment(int x) {
int a = x > 4 || x < 10;
// expected-warning@-1{{overlapping comparisons always evaluate to true}}
int b = x < 2 && x > 5;
// expected-warning@-1{{non-overlapping comparisons always evaluate to false}}
int c = x != 1 || x != 3;
// expected-warning@-1{{overlapping comparisons always evaluate to true}}
int d = x == 1 && x == 2;
// expected-warning@-1{{non-overlapping comparisons always evaluate to false}}
int e = x < 1 || x != 0;
// expected-warning@-1{{overlapping comparisons always evaluate to true}}
}
int returns(int x) {
return x > 4 || x < 10;
// expected-warning@-1{{overlapping comparisons always evaluate to true}}
return x < 2 && x > 5;
// expected-warning@-1{{non-overlapping comparisons always evaluate to false}}
return x != 1 || x != 3;
// expected-warning@-1{{overlapping comparisons always evaluate to true}}
return x == 1 && x == 2;
// expected-warning@-1{{non-overlapping comparisons always evaluate to false}}
return x < 1 || x != 0;
// expected-warning@-1{{overlapping comparisons always evaluate to true}}
}
int integer_conversion(unsigned x, int y) {
return x > 4 || x < 10;
// expected-warning@-1{{overlapping comparisons always evaluate to true}}
return y > 4u || y < 10u;
// expected-warning@-1{{overlapping comparisons always evaluate to true}}
}
int negative_compare(int x) {
return x > -1 || x < 1;
// expected-warning@-1{{overlapping comparisons always evaluate to true}}
}
int no_warning(unsigned x) {
return x >= 0 || x == 1;
// no warning since "x >= 0" is caught by a different tautological warning.
}
struct A {
int x;
int y;
};
int struct_test(struct A a) {
return a.x > 5 && a.y < 1; // no warning, different variables
return a.x > 5 && a.x < 1;
// expected-warning@-1{{non-overlapping comparisons always evaluate to false}}
return a.y == 1 || a.y != 1;
// expected-warning@-1{{overlapping comparisons always evaluate to true}}
}
void char_tests(char c) {
if (c > 'a' || c < 'z') {}
// expected-warning@-1{{overlapping comparisons always evaluate to true}}
if (c > 'z' && c < 'a') {}
// expected-warning@-1{{non-overlapping comparisons always evaluate to false}}
if (c == 'a' && c == 'z') {}
// expected-warning@-1{{non-overlapping comparisons always evaluate to false}}
if (c != 'a' || c != 'z') {}
// expected-warning@-1{{overlapping comparisons always evaluate to true}}
}
void float_tests(float f) {
if (f > 1.0 || f < 2.0) {}
// expected-warning@-1{{overlapping comparisons always evaluate to true}}
if (f > 2.0 && f < 1.0) {}
// expected-warning@-1{{non-overlapping comparisons always evaluate to false}}
if (f == 1.0 && f == 2.0) {}
// expected-warning@-1{{non-overlapping comparisons always evaluate to false}}
if (f != 1.0 || f != 2.0) {}
// expected-warning@-1{{overlapping comparisons always evaluate to true}}
}
void double_tests(double d) {
if (d > 3.5 || d < 4.5) {}
// expected-warning@-1{{overlapping comparisons always evaluate to true}}
if (d > 4.5 && d < 3.5) {}
// expected-warning@-1{{non-overlapping comparisons always evaluate to false}}
if (d == 3.5 && d == 4.5) {}
// expected-warning@-1{{non-overlapping comparisons always evaluate to false}}
if (d != 3.5 || d != 4.5) {}
// expected-warning@-1{{overlapping comparisons always evaluate to true}}
}
void mixed_float_double_tests(float f, double d) {
if (f > 1.0 || d < 2.0) {}
// no warning, different types
if (f > 2.0 && d < 1.0) {}
// no warning, different types
if (f == 1.0 && d == 2.0) {}
// no warning, different types
if (f != 1.0 || d != 2.0) {}
// no warning, different types
}
void float_edge_cases(float f) {
if (f > 0.0 || f < 0.0) {}
// no-warning
if (f > 0.0 && f < 0.0) {}
// expected-warning@-1{{non-overlapping comparisons always evaluate to false}}}
if (f == 0.0 && f == -0.0) {}
// no-warning
if (f != 0.0 || f != -0.0) {}
// no warning
}
void double_edge_cases(double d) {
if (d > 0.0 || d < 0.0) {}
// no-warning
if (d > 0.0 && d < 0.0) {}
// expected-warning@-1{{non-overlapping comparisons always evaluate to false}}
if (d == 0.0 && d == -0.0) {}
// no warning
if (d != 0.0 || d != -0.0) {}
// no warning
}
void float_int_literal_tests(float f) {
if (f > 1 || f < 2) {}
// expected-warning@-1{{overlapping comparisons always evaluate to true}}
if (f > 2 && f < 1) {}
// expected-warning@-1{{non-overlapping comparisons always evaluate to false}}
if (f == 1 && f == 2) {}
// expected-warning@-1{{non-overlapping comparisons always evaluate to false}}
if (f != 1 || f != 2) {}
// expected-warning@-1{{overlapping comparisons always evaluate to true}}
}
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