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From: "geoffreydgr at icloud dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug analyzer/109201] New: GCC Static Analyzer does not generate a div-by-zero warning for the `if ((d.b = 1) / f)` where `f` is 0
Date: Sun, 19 Mar 2023 16:52:24 +0000	[thread overview]
Message-ID: <bug-109201-4@http.gcc.gnu.org/bugzilla/> (raw)

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109201

            Bug ID: 109201
           Summary: GCC Static Analyzer does not generate a div-by-zero
                    warning for the `if ((d.b = 1) / f)` where `f` is 0
           Product: gcc
           Version: 13.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: analyzer
          Assignee: dmalcolm at gcc dot gnu.org
          Reporter: geoffreydgr at icloud dot com
  Target Milestone: ---

GCC Static Analyzer does not generate a div-by-zero warning for the `if ((d.b =
1) / f)` statement, but if it is changed to `if ((d.b = 1) / 0)`, analyzer
generates that warning.

 See it live: https://godbolt.org/z/3f18j9az7

Input:
```c
void __analyzer_eval();

struct a
{
    int b : 6;
} c()
{
    struct a d;
    int e = 2;
    int f = 0;
    if ((d.b = 1) / f)
        if (1 >= d.b <= e)
        {
            __analyzer_eval(0 >= d.b <= e);
        }
}

```

Output:
```
<source>: In function 'c':
<source>:15:13: warning: TRUE
   15 |             __analyzer_eval(0 >= d.b <= e);
      |             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Compiler returned: 0
```

             reply	other threads:[~2023-03-19 16:52 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-03-19 16:52 geoffreydgr at icloud dot com [this message]
2023-03-20 20:07 ` [Bug analyzer/109201] " dmalcolm at gcc dot gnu.org
2023-03-20 20:08 ` dmalcolm at gcc dot gnu.org
2023-03-20 20:13 ` dmalcolm at gcc dot gnu.org

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