[cfe-dev] -Wcatch-incomplete-type-extensions

[Howard Hinnant]

On Jan 24, 2012, at 3:45 PM, Douglas Gregor wrote:

> 
> On Jan 19, 2012, at 10:44 AM, Howard Hinnant wrote:
> 
>> 
>> On Jan 19, 2012, at 1:40 PM, John McCall wrote:
>> 
>>> On Jan 19, 2012, at 10:25 AM, Howard Hinnant wrote:
>>>> On Jan 19, 2012, at 12:39 PM, John McCall wrote:
>>>>>> I'm willing to file a bug on this, but I wanted to get guidance here first.
>>>>> 
>>>>> That is absolutely a bug that we should fix.
>>>> 
>>>> http://llvm.org/bugs/show_bug.cgi?id=11803
>>>> 
>>>>>> g++-4.2 refuses to compile the code that malfunctions, and thus never gets into this situation.
>>>>> 
>>>>> Because it catches a reference to incomplete type?  Rejecting this is not allowed.
>>>> 
>>>> The compiler is required to issue a diagnostic because the code is ill-formed (clang does issue a warning):
>>>> 
>>>> 15.3 [except.handle]/p1:
>>>> 
>>>>> The exception-declaration in a handler describes the type(s) of exceptions that can cause that handler to be entered. The exception-declaration shall not denote an incomplete type, an abstract class type, or an rvalue reference type. The exception-declaration shall not denote a pointer or reference to an incomplete type, other than void*, const void*, volatile void*, or const volatile void*.
>>> 
>>> Okay.  I don't know off-hand why we accept this, then, particularly if GCC does not.
>> 
>> It is because of http://llvm.org/bugs/show_bug.cgi?id=6527
>> 
>> I tried to collect all this information in the bug report (http://llvm.org/bugs/show_bug.cgi?id=11803) so it is there in one place.  And at this point I'm not sure what the best solution is.  But I'm pretty sure we're in an anywhere-but-here situation.
> 
> Agreed. I've made the warning into an error in Clang r148838.

Thanks for looking into this Doug.

Howard