gcc/testsuite/gcc.dg/pr68412.c

   1 /* PR c/68412 */
   2 /* { dg-do compile } */
   3 /* { dg-options "-Wall -Wextra" } */
   4
   5 #define M (sizeof (int) * __CHAR_BIT__)
   6
   7 int
   8 fn1 (int i)
   9 {
  10   return i == (-1 << 8); /* { dg-warning "left shift of negative value" } */
  11 }
  12
  13 int
  14 fn2 (int i)
  15 {
  16   return i == (1 << M); /* { dg-warning "left shift count" } */
  17 }
  18
  19 int
  20 fn3 (int i)
  21 {
  22   return i == 10 << (M - 1); /* { dg-warning "requires" } */
  23 }
  24
  25 int
  26 fn4 (int i)
  27 {
  28   return i == 1 << -1; /* { dg-warning "left shift count" } */
  29 }
  30
  31 int
  32 fn5 (int i)
  33 {
  34   return i == 1 >> M; /* { dg-warning "right shift count" } */
  35 }
  36
  37 int
  38 fn6 (int i)
  39 {
  40   return i == 1 >> -1; /* { dg-warning "right shift count" } */
  41 }