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Date: Sat, 26 Jun 2010 00:53:00 -0000
Subject: [Bug c/44677]  New: Warn for variables incremented but not used
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From: "jsm28 at gcc dot gnu dot org" <gcc-bugzilla@gcc.gnu.org>
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void
f (void)
{
  int i;
  i = 0;
  i++;
}

seems like something a natural generalization of -Wunused-but-set-variable
should warn for; the value of i is only used as part of an increment of i,
so the definition and all uses of this variable could be safely removed.

For a real example of this, see the variable lang_n_infiles in
gcc.c:process_command (I'm testing a patch that removes that variable
along with other changes).


-- 
           Summary: Warn for variables incremented but not used
           Product: gcc
           Version: 4.5.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: jsm28 at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44677