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From: "mhillen at linux dot ibm.com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug rtl-optimization/92294] alias attribute generates incorrect code
Date: Thu, 19 Nov 2020 11:03:23 +0000	[thread overview]
Message-ID: <bug-92294-4-ZiTkQAmesZ@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-92294-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92294

--- Comment #7 from Marius Hillenbrand <mhillen at linux dot ibm.com> ---
A simpler example derived from alias-2.c reproduces this issue on aarch64,
ppc64, and s390x. 

int a;
extern int b __attribute__ ((alias("a")));
int off;

int foo()
{
  /* make sure off is ahead of a and b in .bss, so that a has a non-negative
   * offset relative to the anchor. */
  return off;
}

main()
{
  b=1;
  a=2;
  if (b!=2)
   __builtin_abort ();
  return 0;
}

Note that gcc.c-torture/execute/alias-2.c did not reproduce this issue on
ppc64(le) for me. Removing the array indexing reduces the complexity of the RTL
dumps somewhat.

  parent reply	other threads:[~2020-11-19 11:03 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <bug-92294-4@http.gcc.gnu.org/bugzilla/>
2020-05-07 11:56 ` jakub at gcc dot gnu.org
2020-07-23  6:51 ` rguenth at gcc dot gnu.org
2020-11-13  9:30 ` mhillen at linux dot ibm.com
2020-11-19 11:03 ` mhillen at linux dot ibm.com [this message]
2020-11-19 13:02 ` mhillen at linux dot ibm.com
2020-11-23 20:49 ` rsandifo at gcc dot gnu.org
2021-01-19 17:51 ` cvs-commit at gcc dot gnu.org
2021-01-19 17:53 ` rsandifo at gcc dot gnu.org
2022-02-11  9:13 ` pinskia at gcc dot gnu.org

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