[cfe-dev] warnings in clang

[Sebastian Redl]

Mike Stump wrote:
> On Nov 14, 2008, at 2:55 PM, Argiris Kirtzidis wrote:
>   
>
>> D.ReadUIntPtr(reinterpret_cast<uintptr_t&>(MDC->SemanticDC),  
>> SemaDCPtrID);
>>
>> where 'MDC->SemanticDC' is a pointer (DeclContext*).
>>     
>
> reinterpret_cast<uintptr_t&>?  Never use reinterpret_cast.
>
>    uintptr_t x;
>    D.ReadUIntPtr(x, SemaDCPtrID);
>
> will read a uintptr_t.  This:
>
>    MDC->SemanticDC = (DeclContext*)x;
>
> will convert and store it.
This would be highly dangerous, because the deserializer stores the 
reference you pass it for backpatching. In other words, if you introduce 
a local variable and give it to the deserializer with backpatching 
enable, you're effectively creating a dangling reference.

Sebastian