gnu / gcc / a6d3012b274f38b20e2a57162106f625746af6c6 / . / gcc / testsuite / c-c++-common / Wbool-compare-1.c

/* PR c++/62153 */ | |

/* { dg-do compile } */ | |

/* { dg-options "-Wall" } */ | |

#ifndef __cplusplus | |

# define bool _Bool | |

# define true 1 | |

# define false 0 | |

#endif | |

extern bool foo (void); | |

bool r; | |

enum { E = 4 }; | |

void | |

fn1 (bool b) | |

{ | |

r = b == 2; /* { dg-warning "with boolean expression is always false" } */ | |

r = b != 2; /* { dg-warning "with boolean expression is always true" } */ | |

r = b < 2; /* { dg-warning "with boolean expression is always true" } */ | |

r = b > 2; /* { dg-warning "with boolean expression is always false" } */ | |

r = b <= 2; /* { dg-warning "with boolean expression is always true" } */ | |

r = b >= 2; /* { dg-warning "with boolean expression is always false" } */ | |

r = b == -1; /* { dg-warning "with boolean expression is always false" } */ | |

r = b != -1; /* { dg-warning "with boolean expression is always true" } */ | |

r = b < -1; /* { dg-warning "with boolean expression is always false" } */ | |

r = b > -1; /* { dg-warning "with boolean expression is always true" } */ | |

r = b <= -1; /* { dg-warning "with boolean expression is always false" } */ | |

r = b >= -1; /* { dg-warning "with boolean expression is always true" } */ | |

r = foo () == 2; /* { dg-warning "with boolean expression is always false" } */ | |

r = foo () != 2; /* { dg-warning "with boolean expression is always true" } */ | |

r = foo () < 2; /* { dg-warning "with boolean expression is always true" } */ | |

r = foo () > 2; /* { dg-warning "with boolean expression is always false" } */ | |

r = foo () <= 2; /* { dg-warning "with boolean expression is always true" } */ | |

r = foo () >= 2; /* { dg-warning "with boolean expression is always false" } */ | |

r = b == E; /* { dg-warning "with boolean expression is always false" } */ | |

r = b != E; /* { dg-warning "with boolean expression is always true" } */ | |

r = b < E; /* { dg-warning "with boolean expression is always true" } */ | |

r = b > E; /* { dg-warning "with boolean expression is always false" } */ | |

r = b <= E; /* { dg-warning "with boolean expression is always true" } */ | |

r = b >= E; /* { dg-warning "with boolean expression is always false" } */ | |

/* Swap LHS and RHS. */ | |

r = 2 == b; /* { dg-warning "with boolean expression is always false" } */ | |

r = 2 != b; /* { dg-warning "with boolean expression is always true" } */ | |

r = 2 < b; /* { dg-warning "with boolean expression is always false" } */ | |

r = 2 > b; /* { dg-warning "with boolean expression is always true" } */ | |

r = 2 <= b; /* { dg-warning "with boolean expression is always false" } */ | |

r = 2 >= b; /* { dg-warning "with boolean expression is always true" } */ | |

r = -1 == b; /* { dg-warning "with boolean expression is always false" } */ | |

r = -1 != b; /* { dg-warning "with boolean expression is always true" } */ | |

r = -1 < b; /* { dg-warning "with boolean expression is always true" } */ | |

r = -1 > b; /* { dg-warning "with boolean expression is always false" } */ | |

r = -1 <= b; /* { dg-warning "with boolean expression is always true" } */ | |

r = -1 >= b; /* { dg-warning "with boolean expression is always false" } */ | |

r = E == b; /* { dg-warning "with boolean expression is always false" } */ | |

r = E != b; /* { dg-warning "with boolean expression is always true" } */ | |

r = E < b; /* { dg-warning "with boolean expression is always false" } */ | |

r = E > b; /* { dg-warning "with boolean expression is always true" } */ | |

r = E <= b; /* { dg-warning "with boolean expression is always false" } */ | |

r = E >= b; /* { dg-warning "with boolean expression is always true" } */ | |

/* These are of course fine. */ | |

r = b == false; | |

r = b != false; | |

r = b == true; | |

r = b != true; | |

r = b <= false; | |

r = b > false; | |

r = b < true; | |

r = b >= true; | |

} | |

void | |

fn2 (int i1, int i2) | |

{ | |

r = (i1 == i2) == 2; /* { dg-warning "with boolean expression is always false" } */ | |

r = (i1 == i2) != 2; /* { dg-warning "with boolean expression is always true" } */ | |

r = (i1 == i2) < 2; /* { dg-warning "with boolean expression is always true" } */ | |

r = (i1 == i2) > 2; /* { dg-warning "with boolean expression is always false" } */ | |

r = (i1 == i2) <= 2; /* { dg-warning "with boolean expression is always true" } */ | |

r = (i1 == i2) >= 2; /* { dg-warning "with boolean expression is always false" } */ | |

r = (i1 == i2) == -1; /* { dg-warning "with boolean expression is always false" } */ | |

r = (i1 == i2) != -1; /* { dg-warning "with boolean expression is always true" } */ | |

r = (i1 == i2) < -1; /* { dg-warning "with boolean expression is always false" } */ | |

r = (i1 == i2) > -1; /* { dg-warning "with boolean expression is always true" } */ | |

r = (i1 == i2) <= -1; /* { dg-warning "with boolean expression is always false" } */ | |

r = (i1 == i2) >= -1; /* { dg-warning "with boolean expression is always true" } */ | |

r = (i1 == i2) == E; /* { dg-warning "with boolean expression is always false" } */ | |

r = (i1 == i2) != E; /* { dg-warning "with boolean expression is always true" } */ | |

r = (i1 == i2) < E; /* { dg-warning "with boolean expression is always true" } */ | |

r = (i1 == i2) > E; /* { dg-warning "with boolean expression is always false" } */ | |

r = (i1 == i2) <= E; /* { dg-warning "with boolean expression is always true" } */ | |

r = (i1 == i2) >= E; /* { dg-warning "with boolean expression is always false" } */ | |

} | |

void | |

fn3 (int n, bool b) | |

{ | |

/* Don't warn here. */ | |

r = b == n; | |

r = b != n; | |

r = b < n; | |

r = b > n; | |

r = b <= n; | |

r = b >= n; | |

r = n == E; | |

r = n != E; | |

r = n < E; | |

r = n > E; | |

r = n <= E; | |

r = n >= E; | |

} |