[Bug middle-end/77432] warn about null check after pointer dereference

[msebor at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77432

Martin Sebor <msebor at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |msebor at gcc dot gnu.org
   Last reconfirmed|2016-08-31 00:00:00         |2020-6-8
      Known to fail|                            |10.1.0, 11.0, 7.3.0, 8.2.0,
                   |                            |9.1.0

--- Comment #4 from Martin Sebor <msebor at gcc dot gnu.org> ---
Reconfirming with GCC 11.  The if statement is simplified to if (1 != 0) by
EVRP:

Visiting stmt b_4 = *a_3(D);
Intersecting
  int * [1B, +INF]  EQUIVALENCES: { a_3(D) } (1 elements)
and
  int * VARYING
to
  int * [1B, +INF]  EQUIVALENCES: { a_3(D) } (1 elements)
pushing new range for a_3(D): int * [1B, +INF]  EQUIVALENCES: { a_3(D) } (1
elements)
Visiting stmt if (a_3(D) != 0B)

Visiting conditional with predicate: if (a_3(D) != 0B)

With known ranges
        a_3(D): int * [1B, +INF]  EQUIVALENCES: { a_3(D) } (1 elements)

Predicate evaluates to: 1
gimple_simplified to if (1 != 0)