[Mesa-dev] [PATCH] glsl: type check between switch init-expression and case

[Tapani Pälli]

On 06/10/2014 08:28 AM, Tapani Pälli wrote:
> On 06/09/2014 09:40 PM, Matt Turner wrote:
>> On Mon, Jun 9, 2014 at 4:29 AM, Tapani Pälli <tapani.palli at intel.com> wrote:
>>> Signed-off-by: Tapani Pälli <tapani.palli at intel.com>
>>> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=79724
>>> ---
>>>  src/glsl/ast_to_hir.cpp | 9 +++++++++
>>>  1 file changed, 9 insertions(+)
>>>
>>> diff --git a/src/glsl/ast_to_hir.cpp b/src/glsl/ast_to_hir.cpp
>>> index d1c77f1..131b25f 100644
>>> --- a/src/glsl/ast_to_hir.cpp
>>> +++ b/src/glsl/ast_to_hir.cpp
>>> @@ -4629,6 +4629,15 @@ ast_case_label::hir(exec_list *instructions,
>>>           }
>>>        }
>>>
>>> +      /* Check that types match (no implicit conversions allowed). */
>> Good news. GLSL 4.30 updated the text to say (I think as a
>> clarification, so we should have this behavior always):
> OK, should have realized to check the latest spec too. This is a good
> addition.
>
>> The type of the init-expression value in a switch statement must be a
>> scalar int or uint. The type of the constant-expression value in a case
>> label also must be a scalar int or uint. When any pair of these values
>> is tested for "equal value" and the types do not match, an implicit
>> conversion will be done to convert the int to a uint (see section 4.1.10
>> “Implicit Conversions”) before the compare is done.
>>
>> Please replace this comment with that spec citation in our usual
>> format. I guess we'll need a little bit of code to handle implicit
>> conversions here, but apparently only for int -> uint which is a
>> relief.
> Thanks, I will make the appropriate changes.

Older versions of GLSL spec (like 3.30) does have "There are no implicit
conversions between signed and unsigned integers." though, does this
check need to be version specific or are we safe just supporting the
implicit conversion?

> // Tapani
>