[Bug c/104367] Possible improvements for -Wmisleading-indentation

[msebor at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104367

Martin Sebor <msebor at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |msebor at gcc dot gnu.org

--- Comment #2 from Martin Sebor <msebor at gcc dot gnu.org> ---
Declaring bar()n with attribute nonnull triggers -Wnonnull but only at -O1:

In function ‘foo’,
    inlined from ‘main’ at pr104367.c:15:5:
pr104367.c:11:5: warning: argument 1 null where non-null expected [-Wnonnull]
   11 |     bar(x);
      |     ^~~~~~
pr104367.c: In function ‘main’:
pr104367.c:3:32: note: in a call to function ‘bar’ declared ‘nonnull’
    3 | __attribute__ ((nonnull)) void bar(int *x) {
      |                                ^~~

At -O2 GCC notices the invalid access and emits a trap but doesn't warn:

void foo (int * x)
{
  int _3;

  <bb 2> [local count: 1073741824]:
  if (x_1(D) == 0B)
    goto <bb 3>; [9.81%]
  else
    goto <bb 4>; [90.19%]

  <bb 3> [local count: 105334072]:
  _3 ={v} MEM[(int *)0B];
  __builtin_trap ();

  <bb 4> [local count: 1073741824]:
  return;

}