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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/92479] missing warnings for unreachable codes with break
 (i.e. revive the subset of -Wunreachable-code that fits under clang's
 -Wunreachable-code-break)
Date: Mon, 29 Nov 2021 14:10:20 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D92479

--- Comment #9 from Richard Biener <rguenth at gcc dot gnu.org> ---
Interestingly clang doesn't warn for

int main()
{
  for(int i =3D 1;; i++){
    if(0)
      {
        ++i;
        break;
      }
  }
}

which looks quite stupid (an empty stmt is OK though).  In fact diagnosing
that specifically a 'break' is not reachable and controlling that with its
own option looks bogus.

I'm going to re-interpret -Wunreachable-code-{return,break} to mean to
diagnose unreachable code _after_ a return stmt or a break stmt.  It really
looks like clang went out with a hammer, assigning a different option to
each diagnostic invocation with a different text ...=