gcc/testsuite/c-c++-common/Wtautological-compare-ranges.c

   1 /* { dg-do compile } */
   2 /* { dg-options "-Wtautological-compare -fdiagnostics-show-caret" } */
   3
   4 #define FOO foo
   5
   6 void
   7 fn1 (int foo)
   8 {
   9   if (foo == foo); /* { dg-warning "self-comparison always evaluates to true" } */
  10   /* { dg-begin-multiline-output "" }
  11    if (foo == foo);
  12            ^~
  13      { dg-end-multiline-output "" { target c } } */
  14   /* { dg-begin-multiline-output "" }
  15    if (foo == foo);
  16        ~~~ ^~ ~~~
  17      { dg-end-multiline-output "" { target c++ } } */
  18 }
  19
  20 void
  21 fn2 (int foo)
  22 {
  23   if (FOO == FOO); /* { dg-warning "self-comparison always evaluates to true" } */
  24   /* { dg-begin-multiline-output "" }
  25    if (FOO == FOO);
  26            ^~
  27      { dg-end-multiline-output "" } */
  28 }
  29
  30 void
  31 fn3 (int foo)
  32 {
  33   if ((foo & 16) == 10); /* { dg-warning "bitwise comparison always evaluates to false" } */
  34   /* { dg-begin-multiline-output "" }
  35    if ((foo & 16) == 10);
  36                   ^~
  37      { dg-end-multiline-output "" { target c } } */
  38   /* { dg-begin-multiline-output "" }
  39    if ((foo & 16) == 10);
  40        ~~~~~~~~~~ ^~ ~~
  41      { dg-end-multiline-output "" { target c++ } } */
  42 }