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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/104308] no location info provided for
 [-Wanalyzer-use-of-uninitialized-value] warnings
Date: Mon, 31 Jan 2022 15:56:53 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D104308

David Malcolm <dmalcolm at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|                            |2022-01-31
     Ever confirmed|0                           |1
             Status|UNCONFIRMED                 |ASSIGNED

--- Comment #1 from David Malcolm <dmalcolm at gcc dot gnu.org> ---
Thanks for filing this bug; confirmed.

-Wanalyzer-use-of-uninitialized-value is new as of gcc 12.

Current trunk gives me:
  https://godbolt.org/z/4bfE1TW61
In function =E2=80=98main=E2=80=99:
cc1: warning: use of uninitialized value =E2=80=98*(short unsigned int *)&s=
 + 1=E2=80=99
[CWE-457] [-Wanalyzer-use-of-uninitialized-value]
  =E2=80=98main=E2=80=99: event 1
    |
    |foo.c:2:19:
    |    2 | int main() { char s[5]; memmove(s, s + 1, 2); }
    |      |                   ^
    |      |                   |
    |      |                   (1) region created on stack here
    |
  =E2=80=98main=E2=80=99: event 2
    |
    |cc1:
    | (2): use of uninitialized value =E2=80=98*(short unsigned int *)&s + =
1=E2=80=99 here
    |

where event (1) has a location, but (2) doesn't.=