[Bug c/36299] spurious and undocumented warning with -Waddress for a == 0 when a is an array

[vincent at vinc17 dot org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36299

--- Comment #7 from Vincent Lefèvre <vincent at vinc17 dot org> 2011-03-02 
01:15:23 UTC ---
(In reply to comment #6)
> I think the intention is to warn, at least for a == (void *)0, since the
> address of a cannot be zero or null. So I would say that this is a regression.

But this is valid in C, and in practice, such a test can occur in macro
expansions: a macro can check whether some pointer is null before doing
something with it. There shouldn't be a warning in such a case.