[cfe-commits] r125445 - in /cfe/trunk: include/clang/Sema/Overload.h include/clang/Sema/Sema.h lib/Sema/SemaExprCXX.cpp lib/Sema/SemaOverload.cpp test/CodeGenObjCXX/blocks.mm test/SemaCXX/block-call.cpp test/SemaObjCXX/blocks.mm

[John McCall]

On Feb 13, 2011, at 12:07 PM, Fariborz Jahanian wrote:

> 
> On Feb 13, 2011, at 11:33 AM, John McCall wrote:
> 
>> On Feb 12, 2011, at 11:07 AM, Fariborz Jahanian wrote:
>>> Author: fjahanian
>>> Date: Sat Feb 12 13:07:46 2011
>>> New Revision: 125445
>>> 
>>> URL: http://llvm.org/viewvc/llvm-project?rev=125445&view=rev
>>> Log:
>>> Implement objective-c++'s block pointer type matching involving
>>> types which are contravariance in argument types and covariance
>>> in return types. // rdar://8979379.
>> 
>> To add to Doug's comments:
>> 
>>> +  const FunctionProtoType *FromFunctionType
>>> +    = FromPointeeType->getAs<FunctionProtoType>();
>>> +  const FunctionProtoType *ToFunctionType
>>> +    = ToPointeeType->getAs<FunctionProtoType>();
>>> +  
>>> +  if (FromFunctionType && ToFunctionType) {
>> 
>> You can use an early return here.
>> 
>>> +    if (Context.getCanonicalType(FromPointeeType)
>>> +          == Context.getCanonicalType(ToPointeeType))
>>> +      return true;
>>> +    
>>> +    // Perform the quick checks that will tell us whether these
>>> +    // function types are obviously different.
>>> +    if (FromFunctionType->getNumArgs() != ToFunctionType->getNumArgs() ||
>>> +        FromFunctionType->isVariadic() != ToFunctionType->isVariadic() ||
>>> +        FromFunctionType->getTypeQuals() != ToFunctionType->getTypeQuals())
>>> +      return false;
>> 
>> You should bail out on an ExtInfo mismatch, too.
> 
> Thanks. In r125467 now. What does checking for ExtInfo accomplish beyond the other
> checkings? 

You can give a block a non-standard calling convention.  You generally *shouldn't*, because things like invoking the block via an Objective-C message send will completely break, but you *can*.

John.