[PATCH] handle enumerated types in -Wformat-overflow (PR 80397)

[Jeff Law]

On 04/26/2017 11:05 AM, Martin Sebor wrote:
> On 04/24/2017 03:35 PM, Jeff Law wrote:
>> On 04/11/2017 12:57 PM, Martin Sebor wrote:
>>> In a review of my fix for bug 80364 Jakub pointed out that to
>>> determine whether an argument to an integer directive is of
>>> an integer type the gimple-ssa-sprintf pass tests the type code
>>> for equality to INTEGER_TYPE when it should instead be using
>>> INTEGRAL_TYPE_P().  This has the effect of the pass being unable
>>> to use the available range of arguments of enumerated types,
>>> resulting in both false positives and false negatives, and in
>>> some cases, in emitting suboptimal code.
>>>
>>> The attached patch replaces those tests with INTEGRAL_TYPE_P().
>>>
>>> Since this is not a regression I submit it for GCC 8.
>> You might consider using POINTER_TYPE_P as well.
> 
> You mean rather than (TREE_CODE (type) == POINTER_TYPE)?  Those
> I believe are vestiges of the %p handling that was removed sometime
> last year, and (unless you are recommending I remove them as part
> of this patch) should probably be removed during the next cleanup.Yes, that can be a follow-up cleanup.

For the future, if you find yourself writing something like
TREE_CODE (TREE_TYPE (x)) == POINTER_TYPE, you're usually going to be 
better off using POINTER_TYPE_P (TREE_TYPE (x)).  That allows the code 
to work with C++ references as well as C pointers.


Jeff