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From: "dmalcolm at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug analyzer/108968] fanalyzer false positive with the uninitalised-ness of the stack pointer
Date: Thu, 02 Mar 2023 21:48:05 +0000	[thread overview]
Message-ID: <bug-108968-4-NsPw0JpvuX@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-108968-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108968

--- Comment #17 from David Malcolm <dmalcolm at gcc dot gnu.org> ---
...where trunk emits:

test.c:35:22: warning: dereference of NULL 'ptr' [CWE-476]
[-Wanalyzer-null-dereference]
   35 |         ptr[0] = ~ptr[0];
      |                   ~~~^~~
  'foo': events 1-6
    |
    |   27 |     char *ptr = ((void*)0);
    |      |           ^~~
    |      |           |
    |      |           (1) 'ptr' is NULL
    |   28 | 
    |   29 |     if ( ((get_cpu_info()->current_vcpu))->domain )
    |      |        ~   
    |      |        |
    |      |        (2) following 'false' branch...
    |......
    |   32 |     asm volatile ("cmc");
    |      |     ~~~    
    |      |     |
    |      |     (3) ...to here
    |   33 | 
    |   34 |     if ( ((get_cpu_info()->current_vcpu))->domain )
    |      |        ~   
    |      |        |
    |      |        (4) following 'true' branch...
    |   35 |         ptr[0] = ~ptr[0];
    |      |                   ~~~~~~
    |      |                      |
    |      |                      (5) ...to here
    |      |                      (6) dereference of NULL 'ptr'
    |

  parent reply	other threads:[~2023-03-02 21:48 UTC|newest]

Thread overview: 20+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-02-28 12:41 [Bug c/108968] New: " andrew.cooper3 at citrix dot com
2023-02-28 13:12 ` [Bug c/108968] " schwab@linux-m68k.org
2023-02-28 13:44 ` andrew.cooper3 at citrix dot com
2023-02-28 13:59 ` schwab@linux-m68k.org
2023-02-28 15:41 ` andrew.cooper3 at citrix dot com
2023-02-28 18:56 ` [Bug analyzer/108968] " dmalcolm at gcc dot gnu.org
2023-02-28 19:04 ` andrew.cooper3 at citrix dot com
2023-03-02 19:02 ` cvs-commit at gcc dot gnu.org
2023-03-02 19:25 ` dmalcolm at gcc dot gnu.org
2023-03-02 21:15 ` andrew.cooper3 at citrix dot com
2023-03-02 21:20 ` andrew.cooper3 at citrix dot com
2023-03-02 21:25 ` dmalcolm at gcc dot gnu.org
2023-03-02 21:29 ` dmalcolm at gcc dot gnu.org
2023-03-02 21:34 ` andrew.cooper3 at citrix dot com
2023-03-02 21:35 ` andrew.cooper3 at citrix dot com
2023-03-02 21:41 ` andrew.cooper3 at citrix dot com
2023-03-02 21:46 ` dmalcolm at gcc dot gnu.org
2023-03-02 21:48 ` dmalcolm at gcc dot gnu.org [this message]
2023-03-02 21:52 ` dmalcolm at gcc dot gnu.org
2023-03-29 18:19 ` cvs-commit at gcc dot gnu.org

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