[cfe-commits] r60615 - in /cfe/trunk: include/clang/AST/ASTContext.h include/clang/AST/Expr.h include/clang/AST/Type.h lib/AST/ASTContext.cpp lib/AST/CFG.cpp lib/AST/Expr.cpp lib/AST/StmtIterator.cpp lib/AST/Type.cpp lib/AST/TypeSerialization.cpp lib/CodeGen/CodeGenTypes.cpp lib/Sema/SemaDecl.cpp lib/Sema/SemaExpr.cpp lib/Sema/SemaExprCXX.cpp lib/Sema/SemaStmt.cpp lib/Sema/SemaTemplate.cpp lib/Sema/SemaType.cpp test/SemaCXX/dependent-types.cpp test/SemaCXX/type-dependent-exprs.cpp

[Sebastian Redl]

Douglas Gregor wrote:
> Author: dgregor
> Date: Fri Dec  5 17:32:09 2008
> New Revision: 60615
>
> URL: http://llvm.org/viewvc/llvm-project?rev=60615&view=rev
> Log:
> Introduce basic support for dependent types, type-dependent
> expressions, and value-dependent expressions. This permits us to parse
> some template definitions.
>   
Yay!

> +/// getDependentSizedArrayType - Returns a non-unique reference to
> +/// the type for a dependently-sized array of the specified element
> +/// type. FIXME: We will need these to be uniqued, or at least
> +/// comparable, at some point.
>   
Do VLAs have the same FIXME? Why do we need this?
>    // FIXME: What is the ownership of size expressions in VLAs?
>    VariableArrayType *VAT = cast<VariableArrayType>(AT);
>    return getVariableArrayType(NewEltTy, VAT->getSizeExpr(),
> @@ -1246,6 +1282,16 @@
>      return cast<ArrayType>(getIncompleteArrayType(NewEltTy,
>                                                    IAT->getSizeModifier(),
>                                                   IAT->getIndexTypeQualifier()));
> +
> +  // FIXME: What is the ownership of size expressions in
> +  // dependent-sized array types?
> +  if (const DependentSizedArrayType *DSAT 
> +        = dyn_cast<DependentSizedArrayType>(ATy))
> +    return cast<ArrayType>(
> +                     getDependentSizedArrayType(NewEltTy, 
> +                                                DSAT->getSizeExpr(),
> +                                                DSAT->getSizeModifier(),
> +                                                DSAT->getIndexTypeQualifier()));
>   
VLAs destroy their size expression when they die, so they seem to assume 
ownership. Why is this still a FIXME?
>    
> +// FIXME: Add support for dependent-sized array types in C++?
> +// Does it even make sense to build a CFG for an uninstantiated template?
>   
I'd say no.
> ==============================================================================
> --- cfe/trunk/lib/Sema/SemaExpr.cpp (original)
> +++ cfe/trunk/lib/Sema/SemaExpr.cpp Fri Dec  5 17:32:09 2008
> @@ -490,7 +490,52 @@
>    }
>    // If this reference is not in a block or if the referenced variable is
>    // within the block, create a normal DeclRefExpr.
> -  return new DeclRefExpr(VD, VD->getType().getNonReferenceType(), Loc);
> +
> +  // C++ [temp.dep.expr]p3:
> +  //   An id-expression is type-dependent if it contains:   
> +  bool TypeDependent = false;
>   
I expect the C guys will want this entire block in an if (CPlusPlus).
>  
>    // first, check the condition.
> -  if (!condT->isScalarType()) { // C99 6.5.15p2
> -    Diag(cond->getLocStart(), diag::err_typecheck_cond_expect_scalar) << condT;
> -    return QualType();
> +  if (!cond->isTypeDependent()) {
> +    if (!condT->isScalarType()) { // C99 6.5.15p2
> +      Diag(cond->getLocStart(), diag::err_typecheck_cond_expect_scalar) << condT;
> +      return QualType();
> +    }
>    }
>   
Merge the ifs?
> Added: cfe/trunk/test/SemaCXX/dependent-types.cpp
> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/dependent-types.cpp?rev=60615&view=auto
>
> ==============================================================================
> --- cfe/trunk/test/SemaCXX/dependent-types.cpp (added)
> +++ cfe/trunk/test/SemaCXX/dependent-types.cpp Fri Dec  5 17:32:09 2008
>   
I expect we'll get so many template test cases that we should make a 
SemaTemplate directory to hold those tests.

Great work, Doug.

Sebastian