gcc/testsuite/g++.dg/warn/Wtype-limits.C

   1 /* { dg-do compile } */
   2 /* { dg-options "-Wtype-limits" } */
   3
   4 extern void assert (int);
   5
   6 void a (unsigned char x)
   7 {
   8   if (x < 0)  return;/* { dg-warning "comparison is always false due to limited range of data type" } */
   9   if (x >= 0) return;/* { dg-warning "comparison is always true due to limited range of data type" } */
  10   if (0 > x)  return;/* { dg-warning "comparison is always false due to limited range of data type" } */
  11   if (0 <= x) return;/* { dg-warning "comparison is always true due to limited range of data type" } */
  12   if (x <= 255) /* { dg-warning "comparison is always true due to limited range of data type" } */
  13     return;
  14   if (255 >= x) /* { dg-warning "comparison is always true due to limited range of data type" } */
  15     return;
  16   if ((int)x <= 255) /* { dg-bogus "comparison is always true due to limited range of data type" "" { xfail *-*-* } } */
  17     return;
  18   if (255 >= (unsigned char) 1)
  19     return;
  20
  21 }
  22
  23 void b (unsigned short x)
  24 {
  25   if (x < 0)  return;/* { dg-warning "comparison is always false due to limited range of data type" } */
  26   if (x >= 0) return;/* { dg-warning "comparison is always true due to limited range of data type" } */
  27   if (0 > x)  return;/* { dg-warning "comparison is always false due to limited range of data type" } */
  28   if (0 <= x) return;/* { dg-warning "comparison is always true due to limited range of data type" } */
  29 }
  30
  31 void c (unsigned int x)
  32 {
  33   if (x < 0)  return;/* { dg-warning "comparison of unsigned expression in '< 0' is always false" } */
  34   if (x >= 0) return;/* { dg-warning "comparison of unsigned expression in '>= 0' is always true" } */
  35   if (0 > x)  return;/* { dg-warning "comparison of unsigned expression in '< 0' is always false" } */
  36   if (0 <= x) return;/* { dg-warning "comparison of unsigned expression in '>= 0' is always true" } */
  37   if (1U >= 0) return;
  38   if (1U < 0) return;
  39   if (0 <= 1U) return;
  40   if (0 > 1U) return;
  41 }
  42
  43 void d (unsigned long x)
  44 {
  45   if (x < 0)  return;/* { dg-warning "comparison of unsigned expression in '< 0' is always false" } */
  46   if (x >= 0) return;/* { dg-warning "comparison of unsigned expression in '>= 0' is always true" } */
  47   if (0 > x)  return;/* { dg-warning "comparison of unsigned expression in '< 0' is always false" } */
  48   if (0 <= x) return;/* { dg-warning "comparison of unsigned expression in '>= 0' is always true" } */
  49 }
  50
  51 void e (unsigned long long x)
  52 {
  53   if (x < 0)  return;/* { dg-warning "comparison of unsigned expression in '< 0' is always false" } */
  54   if (x >= 0) return;/* { dg-warning "comparison of unsigned expression in '>= 0' is always true" } */
  55   if (0 > x)  return;/* { dg-warning "comparison of unsigned expression in '< 0' is always false" } */
  56   if (0 <= x) return;/* { dg-warning "comparison of unsigned expression in '>= 0' is always true" } */
  57 }
  58
  59 int test (int x)
  60 {
  61   if ((long long)x <= 0x123456789ABCLL) /* { dg-bogus "comparison is always true due to limited range of data type" "" { xfail *-*-* } } */
  62     return 1;
  63   else
  64     return 0;
  65 }
  66
  67 template <typename Int, Int D>
  68 void f(Int x) {
  69   assert(0 <= x and x <= D);
  70 }
  71
  72 void ff(void) {
  73   f<unsigned char, 2>(5);
  74   f<signed char, 2>(5);
  75 }
  76
  77 template <typename Int, Int D>
  78 void g(void) {
  79   assert(0 <= D);
  80 }
  81 void gg(void) {
  82   g<unsigned char, 2>();
  83 }
  84