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From: "vincent-gcc at vinc17 dot net" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/95057] New: missing -Wunused-but-set-variable warning on
 multiple assignments, not all of them used
Date: Mon, 11 May 2020 12:50:32 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D95057

            Bug ID: 95057
           Summary: missing -Wunused-but-set-variable warning on multiple
                    assignments, not all of them used
           Product: gcc
           Version: 10.1.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: vincent-gcc at vinc17 dot net
  Target Milestone: ---

With -Wunused-but-set-variable, GCC does not warn in the following cases:

int f (int i)
{
  int j;
  j =3D i + 1;  /* unused */
  j =3D i + 2;
  return j;
}

int g (int i)
{
  int j, k;
  j =3D i + 1;
  k =3D j + 1;
  j =3D i + 2;  /* unused */
  return k;
}

Note: it is possible that PR44677 may be regarded as a particular case of t=
his
bug.=