[PATCH] Fix middle-end/67133, part 1

[Jeff Law]

On 08/14/2015 07:29 AM, Marek Polacek wrote:
> On Fri, Aug 14, 2015 at 03:14:10PM +0200, Richard Biener wrote:
>> On Fri, Aug 14, 2015 at 1:20 PM, Marek Polacek <polacek@redhat.com> wrote:
>>> As outlined in the PR, this fixes one ICE.  The code in question here
>>> tries to determine whether OP can be derived as non-NULL.  In case the
>>> function has the nonnull attribute that applies to all the arguments,
>>> we want to see whether OP is in this argument list.  But nonnull only
>>> appertains to pointers.  Some ssa_names don't have a type so check for
>>> that first instead of segv before looking at its tree code.
>>
>> Huh?  All but released SSA names have a type.  So this gets invoked on dead code
>
> I suppose so.  It gets
>   <ssa_name 0x7ffff1890948 nothrow var <var_decl 0x7ffff188df30 c>def_stmt
>
>      version 13 in-free-list>
>
> (it didn't ICE before r209891 because the operand_equal_p check came first and
> returned false so we didn't check the type).
Let's track this down -- nothing should be referencing anything in the 
SSA_NAME freelist.

Jeff