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From: "gabravier at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/96565] New: Failure to optimize out VLA even
 though it is left unused
Date: Tue, 11 Aug 2020 10:56:09 +0000
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X-Bugzilla-Component: tree-optimization
X-Bugzilla-Version: 11.0
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D96565

            Bug ID: 96565
           Summary: Failure to optimize out VLA even though it is left
                    unused
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: gabravier at gmail dot com
  Target Milestone: ---

bool g(void);

void f(int x)
{
    char arr[x];

    arr[0] =3D 0;

    if (g())
        abort();
}

The VLA can be removed. This transformation is done by LLVM, but not by GCC=
.=