gcc/testsuite/c-c++-common/Wbool-compare-2.c

   1 /* PR c/64610 */
   2 /* { dg-do compile } */
   3 /* { dg-options "-Wbool-compare" } */
   4
   5 #ifndef __cplusplus
   6 # define bool _Bool
   7 # define true 1
   8 # define false 0
   9 #endif
  10
  11 extern bool foo (void);
  12
  13 enum { A, B };
  14
  15 int
  16 fn1 (bool b)
  17 {
  18   int r = 0;
  19
  20   r += b >= 0; /* { dg-warning "with boolean expression is always true" } */
  21   r += b > 0;
  22   r += b < 0; /* { dg-warning "with boolean expression is always false" } */
  23   r += b <= 0;
  24
  25   r += b >= 1;
  26   r += b > 1; /* { dg-warning "with boolean expression is always false" } */
  27   r += b < 1;
  28   r += b <= 1; /* { dg-warning "with boolean expression is always true" } */
  29
  30   r += foo () >= 0; /* { dg-warning "with boolean expression is always true" } */
  31   r += foo () > 0;
  32   r += foo () < 0; /* { dg-warning "with boolean expression is always false" } */
  33   r += foo () <= 0;
  34
  35   r += foo () >= 1;
  36   r += foo () > 1; /* { dg-warning "with boolean expression is always false" } */
  37   r += foo () < 1;
  38   r += foo () <= 1; /* { dg-warning "with boolean expression is always true" } */
  39
  40   r += b >= A; /* { dg-warning "with boolean expression is always true" } */
  41   r += b > A;
  42   r += b < A; /* { dg-warning "with boolean expression is always false" } */
  43   r += b <= A;
  44
  45   r += b >= B;
  46   r += b > B; /* { dg-warning "with boolean expression is always false" } */
  47   r += b < B;
  48   r += b <= B; /* { dg-warning "with boolean expression is always true" } */
  49
  50   /* Swap LHS and RHS.  */
  51   r += 0 >= b;
  52   r += 0 > b; /* { dg-warning "with boolean expression is always false" } */
  53   r += 0 < b;
  54   r += 0 <= b; /* { dg-warning "with boolean expression is always true" } */
  55
  56   r += 1 >= b; /* { dg-warning "with boolean expression is always true" } */
  57   r += 1 > b;
  58   r += 1 < b; /* { dg-warning "with boolean expression is always false" } */
  59   r += 1 <= b;
  60
  61   r += 0 >= foo ();
  62   r += 0 > foo (); /* { dg-warning "with boolean expression is always false" } */
  63   r += 0 < foo ();
  64   r += 0 <= foo (); /* { dg-warning "with boolean expression is always true" } */
  65
  66   r += 1 >= foo (); /* { dg-warning "with boolean expression is always true" } */
  67   r += 1 > foo ();
  68   r += 1 < foo (); /* { dg-warning "with boolean expression is always false" } */
  69   r += 1 <= foo ();
  70
  71   r += A >= b;
  72   r += A > b; /* { dg-warning "with boolean expression is always false" } */
  73   r += A < b;
  74   r += A <= b; /* { dg-warning "with boolean expression is always true" } */
  75
  76   r += B >= b; /* { dg-warning "with boolean expression is always true" } */
  77   r += B > b;
  78   r += B < b; /* { dg-warning "with boolean expression is always false" } */
  79   r += B <= b;
  80
  81   return r;
  82 }
  83
  84 int
  85 fn2 (int i, int j)
  86 {
  87   int r = 0;
  88
  89   r += (i == j) >= 0; /* { dg-warning "with boolean expression is always true" } */
  90   r += (i == j) > 0;
  91   r += (i == j) < 0; /* { dg-warning "with boolean expression is always false" } */
  92   r += (i == j) <= 0;
  93
  94   r += (i == j) >= 1;
  95   r += (i == j) > 1; /* { dg-warning "with boolean expression is always false" } */
  96   r += (i == j) < 1;
  97   r += (i == j) <= 1; /* { dg-warning "with boolean expression is always true" } */
  98
  99   return r;
 100 }