Implement C++ DR481, which clarifies that the scope of template
parameters starts at the end of the template-parameter rather than at
the point where the template parameter name is encounted. For example,
given:
typedef unsigned char T;
template<typename T = T> struct X0 { };
The "T" in the default argument refers to the typedef of "unsigned
char", rather than referring to the newly-introduced template type
parameter 'T'.
Addresses <rdar://problem/8122812>.
llvm-svn: 107354
diff --git a/clang/lib/Parse/ParseTemplate.cpp b/clang/lib/Parse/ParseTemplate.cpp
index 9e95ca9..64306da 100644
--- a/clang/lib/Parse/ParseTemplate.cpp
+++ b/clang/lib/Parse/ParseTemplate.cpp
@@ -471,22 +471,19 @@
return DeclPtrTy();
}
- DeclPtrTy TypeParam = Actions.ActOnTypeParameter(CurScope, TypenameKeyword,
- Ellipsis, EllipsisLoc,
- KeyLoc, ParamName, NameLoc,
- Depth, Position);
-
- // Grab a default type id (if given).
+ // Grab a default argument (if available).
+ // Per C++0x [basic.scope.pdecl]p9, we parse the default argument before
+ // we introduce the type parameter into the local scope.
+ SourceLocation EqualLoc;
+ TypeTy *DefaultArg = 0;
if (Tok.is(tok::equal)) {
- SourceLocation EqualLoc = ConsumeToken();
- SourceLocation DefaultLoc = Tok.getLocation();
- TypeResult DefaultType = ParseTypeName();
- if (!DefaultType.isInvalid())
- Actions.ActOnTypeParameterDefault(TypeParam, EqualLoc, DefaultLoc,
- DefaultType.get());
+ EqualLoc = ConsumeToken();
+ DefaultArg = ParseTypeName().get();
}
-
- return TypeParam;
+
+ return Actions.ActOnTypeParameter(CurScope, TypenameKeyword, Ellipsis,
+ EllipsisLoc, KeyLoc, ParamName, NameLoc,
+ Depth, Position, EqualLoc, DefaultArg);
}
/// ParseTemplateTemplateParameter - Handle the parsing of template
@@ -541,28 +538,28 @@
TemplateParams.size(),
RAngleLoc);
- Parser::DeclPtrTy Param
- = Actions.ActOnTemplateTemplateParameter(CurScope, TemplateLoc,
- ParamList, ParamName,
- NameLoc, Depth, Position);
-
- // Get the a default value, if given.
+ // Grab a default argument (if available).
+ // Per C++0x [basic.scope.pdecl]p9, we parse the default argument before
+ // we introduce the template parameter into the local scope.
+ SourceLocation EqualLoc;
+ ParsedTemplateArgument DefaultArg;
if (Tok.is(tok::equal)) {
- SourceLocation EqualLoc = ConsumeToken();
- ParsedTemplateArgument Default = ParseTemplateTemplateArgument();
- if (Default.isInvalid()) {
+ EqualLoc = ConsumeToken();
+ DefaultArg = ParseTemplateTemplateArgument();
+ if (DefaultArg.isInvalid()) {
Diag(Tok.getLocation(),
diag::err_default_template_template_parameter_not_template);
static const tok::TokenKind EndToks[] = {
tok::comma, tok::greater, tok::greatergreater
};
SkipUntil(EndToks, 3, true, true);
- return Param;
- } else if (Param)
- Actions.ActOnTemplateTemplateParameterDefault(Param, EqualLoc, Default);
+ }
}
-
- return Param;
+
+ return Actions.ActOnTemplateTemplateParameter(CurScope, TemplateLoc,
+ ParamList, ParamName,
+ NameLoc, Depth, Position,
+ EqualLoc, DefaultArg);
}
/// ParseNonTypeTemplateParameter - Handle the parsing of non-type
@@ -571,13 +568,6 @@
/// template-parameter:
/// ...
/// parameter-declaration
-///
-/// NOTE: It would be ideal to simply call out to ParseParameterDeclaration(),
-/// but that didn't work out to well. Instead, this tries to recrate the basic
-/// parsing of parameter declarations, but tries to constrain it for template
-/// parameters.
-/// FIXME: We need to make a ParseParameterDeclaration that works for
-/// non-type template parameters and normal function parameters.
Parser::DeclPtrTy
Parser::ParseNonTypeTemplateParameter(unsigned Depth, unsigned Position) {
SourceLocation StartLoc = Tok.getLocation();
@@ -601,13 +591,13 @@
return DeclPtrTy();
}
- // Create the parameter.
- DeclPtrTy Param = Actions.ActOnNonTypeTemplateParameter(CurScope, ParamDecl,
- Depth, Position);
-
// If there is a default value, parse it.
+ // Per C++0x [basic.scope.pdecl]p9, we parse the default argument before
+ // we introduce the template parameter into the local scope.
+ SourceLocation EqualLoc;
+ OwningExprResult DefaultArg(Actions);
if (Tok.is(tok::equal)) {
- SourceLocation EqualLoc = ConsumeToken();
+ EqualLoc = ConsumeToken();
// C++ [temp.param]p15:
// When parsing a default template-argument for a non-type
@@ -616,15 +606,15 @@
// operator.
GreaterThanIsOperatorScope G(GreaterThanIsOperator, false);
- OwningExprResult DefaultArg = ParseAssignmentExpression();
+ DefaultArg = ParseAssignmentExpression();
if (DefaultArg.isInvalid())
SkipUntil(tok::comma, tok::greater, true, true);
- else if (Param)
- Actions.ActOnNonTypeTemplateParameterDefault(Param, EqualLoc,
- move(DefaultArg));
}
- return Param;
+ // Create the parameter.
+ return Actions.ActOnNonTypeTemplateParameter(CurScope, ParamDecl,
+ Depth, Position, EqualLoc,
+ move(DefaultArg));
}
/// \brief Parses a template-id that after the template name has