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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/109959] `(a > 1) ? 0 : (a == 1)` is not optimized when spelled out at -O2+
Date: Mon, 07 Aug 2023 00:26:39 +0000	[thread overview]
Message-ID: <bug-109959-4-9u5kbuwUcJ@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-109959-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109959

--- Comment #9 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
+FAIL: c-c++-common/Wrestrict.c  -Wc++-compat  (test for excess errors)
Excess errors:
/home/apinski/src/upstream-gcc-git/gcc/gcc/testsuite/c-c++-common/Wrestrict.c:684:3:
warning: 'strcpy' accessing 2 bytes at offsets [0, 1] and 0 overlaps between 1
and 2 bytes at offset [0, 1] [-Wrestrict]
  T (8, "0", a + r, a);   /* { dg-warning "accessing between 1 and 2 bytes at
offsets \\\[0, 1] and 0 overlaps up to 2 bytes at offset \\\[0, 1]" "strcpy" {
xfail *-*-*} } */

Looks like the dg-warning needs to be updated and the xfail removed.
we have:
```
strcpy (a+[0,1], a);
```



/home/apinski/src/upstream-gcc-git/gcc/gcc/testsuite/c-c++-common/Wrestrict.c:863:3:
warning: 'strncpy' accessing 1 byte at offsets 0 and [0, 1] may overlap 1 byte
at offset 0 [-Wrestrict]

  T ("0123", a, a + i, 1);

In this case a and a+[0,1] can overlap for strncpy even for size of 1.

/home/apinski/src/upstream-gcc-git/gcc/gcc/testsuite/c-c++-common/Wrestrict.c:866:3:
warning: 'strncpy' accessing 2 bytes at offsets 0 and [0, 1] overlaps between 1
and 2 bytes at offset [0, 1] [-Wrestrict]
  T ("0123", a, a + i, 2);   /* { dg-warning "accessing 2 bytes at offsets 0
and \\\[0, 1] may overlap 1 byte at offset 1" "strncpy" { xfail *-*-* } } */

Just like the first case.

  parent reply	other threads:[~2023-08-07  0:26 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-05-24 22:10 [Bug tree-optimization/109959] New: `(a > 1) ? 0 : (a == 1)` is not optimized when spelled out pinskia at gcc dot gnu.org
2023-05-24 22:16 ` [Bug tree-optimization/109959] `(a > 1) ? 0 : (a == 1)` is not optimized when spelled out at -O2+ pinskia at gcc dot gnu.org
2023-05-24 22:17 ` pinskia at gcc dot gnu.org
2023-05-24 22:21 ` pinskia at gcc dot gnu.org
2023-05-25  3:39 ` pinskia at gcc dot gnu.org
2023-05-25  7:57 ` rguenth at gcc dot gnu.org
2023-06-07 22:36 ` pinskia at gcc dot gnu.org
2023-06-07 22:48 ` pinskia at gcc dot gnu.org
2023-08-06 18:19 ` pinskia at gcc dot gnu.org
2023-08-06 21:12 ` pinskia at gcc dot gnu.org
2023-08-07  0:26 ` pinskia at gcc dot gnu.org [this message]
2023-08-07  1:52 ` pinskia at gcc dot gnu.org
2023-08-07  5:09 ` pinskia at gcc dot gnu.org
2023-08-07 14:47 ` cvs-commit at gcc dot gnu.org
2023-08-07 14:48 ` pinskia at gcc dot gnu.org

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