94 lines
2.7 KiB
C
94 lines
2.7 KiB
C
// RUN: %clang_cc1 -fsyntax-only -verify %s
|
|
|
|
int foo(int x) {
|
|
return x == x; // expected-warning {{self-comparison always evaluates to true}}
|
|
}
|
|
|
|
int foo2(int x) {
|
|
return (x) != (((x))); // expected-warning {{self-comparison always evaluates to false}}
|
|
}
|
|
|
|
void foo3(short s, short t) {
|
|
if (s == s) {} // expected-warning {{self-comparison always evaluates to true}}
|
|
if (s == t) {} // no-warning
|
|
}
|
|
|
|
void foo4(void* v, void* w) {
|
|
if (v == v) {} // expected-warning {{self-comparison always evaluates to true}}
|
|
if (v == w) {} // no-warning
|
|
}
|
|
|
|
int qux(int x) {
|
|
return x < x; // expected-warning {{self-comparison}}
|
|
}
|
|
|
|
int qux2(int x) {
|
|
return x > x; // expected-warning {{self-comparison}}
|
|
}
|
|
|
|
int bar(float x) {
|
|
return x == x; // no-warning
|
|
}
|
|
|
|
int bar2(float x) {
|
|
return x != x; // no-warning
|
|
}
|
|
|
|
#define IS_THE_ANSWER(x) (x == 42)
|
|
|
|
int macro_comparison() {
|
|
return IS_THE_ANSWER(42);
|
|
}
|
|
|
|
// Don't complain in unevaluated contexts.
|
|
int compare_sizeof(int x) {
|
|
return sizeof(x == x); // no-warning
|
|
}
|
|
|
|
int array_comparisons() {
|
|
int array1[2];
|
|
int array2[2];
|
|
|
|
//
|
|
// compare same array
|
|
//
|
|
return array1 == array1; // expected-warning{{self-comparison always evaluates to true}}
|
|
return array1 != array1; // expected-warning{{self-comparison always evaluates to false}}
|
|
return array1 < array1; // expected-warning{{self-comparison always evaluates to false}}
|
|
return array1 <= array1; // expected-warning{{self-comparison always evaluates to true}}
|
|
return array1 > array1; // expected-warning{{self-comparison always evaluates to false}}
|
|
return array1 >= array1; // expected-warning{{self-comparison always evaluates to true}}
|
|
|
|
//
|
|
// compare different arrays
|
|
//
|
|
return array1 == array2; // expected-warning{{array comparison always evaluates to false}}
|
|
return array1 != array2; // expected-warning{{array comparison always evaluates to true}}
|
|
|
|
//
|
|
// we don't know what these are going to be
|
|
//
|
|
return array1 < array2; // expected-warning{{array comparison always evaluates to a constant}}
|
|
return array1 <= array2; // expected-warning{{array comparison always evaluates to a constant}}
|
|
return array1 > array2; // expected-warning{{array comparison always evaluates to a constant}}
|
|
return array1 >= array2; // expected-warning{{array comparison always evaluates to a constant}}
|
|
|
|
}
|
|
|
|
// Don't issue a warning when either the left or right side of the comparison
|
|
// results from a macro expansion. <rdar://problem/8435950>
|
|
#define R8435950_A i
|
|
#define R8435950_B i
|
|
|
|
int R8435950(int i) {
|
|
if (R8435950_A == R8435950_B) // no-warning
|
|
return 0;
|
|
return 1;
|
|
}
|
|
|
|
__attribute__((weak)) int weak_1[3];
|
|
__attribute__((weak)) int weak_2[3];
|
|
_Bool compare_weak() {
|
|
return weak_1 == weak_2;
|
|
}
|