[cfe-commits] r81847 - in /cfe/trunk/lib/Sema: SemaDeclCXX.cpp SemaExprCXX.cpp

[Douglas Gregor]

On Sep 14, 2009, at 11:28 PM, Anders Carlsson wrote:

> Author: andersca
> Date: Tue Sep 15 01:28:28 2009
> New Revision: 81847
>
> URL: http://llvm.org/viewvc/llvm-project?rev=81847&view=rev
> Log:
> When performing an user defined conversion sequence, perform the  
> initial standard conversion sequence. This lets us remove a  
> workaround in SemaCompleteConstructorCall.
>
> Modified:
>    cfe/trunk/lib/Sema/SemaDeclCXX.cpp
>    cfe/trunk/lib/Sema/SemaExprCXX.cpp
>
> Modified: cfe/trunk/lib/Sema/SemaDeclCXX.cpp
> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaDeclCXX.cpp?rev=81847&r1=81846&r2=81847&view=diff
>
> = 
> = 
> = 
> = 
> = 
> = 
> = 
> = 
> ======================================================================
> --- cfe/trunk/lib/Sema/SemaDeclCXX.cpp (original)
> +++ cfe/trunk/lib/Sema/SemaDeclCXX.cpp Tue Sep 15 01:28:28 2009
> @@ -3243,12 +3243,6 @@
>     Expr *Arg;
>     if (i < NumArgs) {
>       Arg = Args[i];
> -
> -      // Pass the argument.
> -      if (PerformCopyInitialization(Arg, ProtoArgType, "passing"))
> -        return true;
> -
> -      Args[i] = 0;
>     } else {
>       ParmVarDecl *Param = Constructor->getParamDecl(i);
>
>
> Modified: cfe/trunk/lib/Sema/SemaExprCXX.cpp
> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaExprCXX.cpp?rev=81847&r1=81846&r2=81847&view=diff
>
> = 
> = 
> = 
> = 
> = 
> = 
> = 
> = 
> ======================================================================
> --- cfe/trunk/lib/Sema/SemaExprCXX.cpp (original)
> +++ cfe/trunk/lib/Sema/SemaExprCXX.cpp Tue Sep 15 01:28:28 2009
> @@ -971,17 +971,34 @@
>       return true;
>     break;
>
> -  case ImplicitConversionSequence::UserDefinedConversion:
> -    {
> +  case ImplicitConversionSequence::UserDefinedConversion: {
> +
>       FunctionDecl *FD = ICS.UserDefined.ConversionFunction;
>       CastExpr::CastKind CastKind = CastExpr::CK_Unknown;
> -      if (isa<CXXConversionDecl>(FD))
> +      QualType BeforeToType;
> +      if (const CXXConversionDecl *Conv =  
> dyn_cast<CXXConversionDecl>(FD)) {
>         CastKind = CastExpr::CK_UserDefinedConversion;
> -      else if (isa<CXXConstructorDecl>(FD))
> +
> +        // If the user-defined conversion is specified by a  
> conversion function,
> +        // the initial standard conversion sequence converts the  
> source type to
> +        // the implicit object parameter of the conversion function.
> +        BeforeToType = Context.getTagDeclType(Conv->getParent());

This isn't quite right.  The conversion function might be cv- 
qualified, and we're not taking that into account here. Amusingly,  
PerformObjectArgumentInitialization *also* seems to get that wrong.  
Argh!

> +      } else if (const CXXConstructorDecl *Ctor =
> +                  dyn_cast<CXXConstructorDecl>(FD)) {
>         CastKind = CastExpr::CK_ConstructorConversion;
> +
> +        // If the user-defined conversion is specified by a  
> constructor, the
> +        // initial standard conversion sequence converts the source  
> type to the
> +        // type required by the argument of the constructor
> +        BeforeToType = Ctor->getParamDecl(0)->getType();
> +      }
>       else
>         assert(0 && "Unknown conversion function kind!");
>
> +      if (PerformImplicitConversion(From, BeforeToType,
> +                                    ICS.UserDefined.Before,  
> "converting"))
> +        return true;

PerformCopyInitialization would be better here, because it handles  
conversion to a reference type (e.g., reference binding), which is not  
strictly an "implicit conversion".

	- Doug