[Bug c/86093] [8/9 Regression] volatile ignored on pointer in C

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86093

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED
                 CC|                            |jakub at gcc dot gnu.org
           Assignee|unassigned at gcc dot gnu.org      |jakub at gcc dot gnu.org

--- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Started with r255021.

genmatch emits all checks as x == y || operand_equal_p (x, y, 0), the reason
why e.g.
long volatile i;
long foo (void) { return i - i; }
isn't optimized into 0 is that we actually wrap i into a NOP_EXPR to remove
quals and only do MINUS_EXPR on the result of those NOP_EXPRs, which don't
compare equal as pointers.  So I think we should just do the same with
POINTER_DIFF_EXPR, cast the operands to unqualified pointers.