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From: "kristerw at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/113703] ivopts miscompiles loop
Date: Thu, 01 Feb 2024 15:30:36 +0000	[thread overview]
Message-ID: <bug-113703-4-7UMEMLfXM0@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-113703-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113703

--- Comment #3 from Krister Walfridsson <kristerw at gcc dot gnu.org> ---
Oops. I messed up the test case...  It "works", but the actual values does not
make sense...

The following is better:

int main()
{
  long pgsz = sysconf (_SC_PAGESIZE);
  void *p = mmap (NULL, pgsz * 2, PROT_READ|PROT_WRITE,
     MAP_ANONYMOUS|MAP_PRIVATE, 0, 0);
  if (p == MAP_FAILED)
    return 0;
  mprotect (p+pgsz, pgsz, PROT_NONE);
  uintptr_t n = -2 - (uintptr_t)(p+pgsz);
  f1 (p+pgsz, -2, n);
  return 0;
}

  parent reply	other threads:[~2024-02-01 15:30 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-02-01 11:17 [Bug tree-optimization/113703] New: " kristerw at gcc dot gnu.org
2024-02-01 14:12 ` [Bug tree-optimization/113703] " rguenth at gcc dot gnu.org
2024-02-01 15:01 ` kristerw at gcc dot gnu.org
2024-02-01 15:30 ` kristerw at gcc dot gnu.org [this message]
2024-02-05 10:04 ` rguenth at gcc dot gnu.org
2024-02-06 11:33 ` rguenth at gcc dot gnu.org

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