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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/105285] False positive with
 -Wanalyzer-null-dereference in git.git's reftable/reader.c
Date: Wed, 27 Apr 2022 18:08:52 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D105285

--- Comment #7 from David Malcolm <dmalcolm at gcc dot gnu.org> ---
For (b), I'm not convinced git's code is totally correct here.

The early-reject case in reader_get_block returns 0:

  if (off >=3D r->size)
    return 0;

but at the caller, the condition is < 0:

  err =3D reader_get_block(r, &block, next_off, guess_block_size);
  if (err < 0)
    goto done;

so if the early reject does happen, the returned "err" will be zero, not
less-than-zero.

Is that a problem?=