[cfe-commits] r63394 - in /cfe/trunk: lib/CodeGen/CGExprScalar.cpp test/CodeGen/sizeof-vla.c

[Anders Carlsson]

30 jan 2009 kl. 09.31 skrev Eli Friedman:

> On Fri, Jan 30, 2009 at 8:41 AM, Anders Carlsson <andersca at mac.com>  
> wrote:
>> @@ -684,7 +684,10 @@
>>        // sizeof(type) - make sure to emit the VLA size.
>>        CGF.EmitVLASize(TypeToSize);
>>      }
>> -      return CGF.GetVLASize(VAT);
>> +
>> +      llvm::Value *VLASize = CGF.GetVLASize(VAT);
>> +      return Builder.CreateIntCast(VLASize, ConvertType(E- 
>> >getType()),
>> +                                   false, "conv");
>>    }
>>  }
>
> This seems like a relatively late place to put the cast; we should be
> computing the size in type size_t, I think.  Are you sure there isn't
> a missing cast earlier?
>
> -Eli

Hmm, yeah - we could probably add an implicit cast to the size_t type  
for the VLA size expr. Not sure what something like

int a[(unsigned long long)f()]

would do in 32-bit, but given that the alloca instruction only takes a  
32-bit constant that isn't an issue anyway :)
What do you think?

Anders