r294641 - Disallow explicit instantiation and explicit specialization for deduction guides.
Richard Smith via cfe-commits
cfe-commits at lists.llvm.org
Thu Feb 9 14:47:52 PST 2017
Author: rsmith
Date: Thu Feb 9 16:47:51 2017
New Revision: 294641
URL: http://llvm.org/viewvc/llvm-project?rev=294641&view=rev
Log:
Disallow explicit instantiation and explicit specialization for deduction guides.
Modified:
cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td
cfe/trunk/lib/Sema/SemaDecl.cpp
cfe/trunk/lib/Sema/SemaTemplate.cpp
cfe/trunk/test/CXX/temp/temp.deduct.guide/p1.cpp
cfe/trunk/www/cxx_status.html
Modified: cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td?rev=294641&r1=294640&r2=294641&view=diff
==============================================================================
--- cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td (original)
+++ cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td Thu Feb 9 16:47:51 2017
@@ -1991,6 +1991,8 @@ def err_deduction_guide_name_not_class_t
"template template parameter|dependent template name}0 %1">;
def err_deduction_guide_defines_function : Error<
"deduction guide cannot have a function definition">;
+def err_deduction_guide_specialized : Error<"deduction guide cannot be "
+ "%select{explicitly instantiated|explicitly specialized}0">;
// C++1y deduced return types
def err_auto_fn_deduction_failure : Error<
Modified: cfe/trunk/lib/Sema/SemaDecl.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaDecl.cpp?rev=294641&r1=294640&r2=294641&view=diff
==============================================================================
--- cfe/trunk/lib/Sema/SemaDecl.cpp (original)
+++ cfe/trunk/lib/Sema/SemaDecl.cpp Thu Feb 9 16:47:51 2017
@@ -7657,8 +7657,9 @@ static FunctionDecl* CreateNewFunctionDe
} else if (Name.getNameKind() == DeclarationName::CXXDeductionGuideName) {
SemaRef.CheckDeductionGuideDeclarator(D, R, SC);
- // We don't need to store any extra information for a deduction guide, so
+ // We don't need to store much extra information for a deduction guide, so
// just model it as a plain FunctionDecl.
+ // FIXME: Store IsExplicit!
return FunctionDecl::Create(SemaRef.Context, DC,
D.getLocStart(),
NameInfo, R, TInfo, SC, isInline,
@@ -9149,6 +9150,13 @@ bool Sema::CheckFunctionDeclaration(Scop
} else if (CXXConversionDecl *Conversion
= dyn_cast<CXXConversionDecl>(NewFD)) {
ActOnConversionDeclarator(Conversion);
+ } else if (NewFD->isDeductionGuide() &&
+ NewFD->getTemplateSpecializationKind() ==
+ TSK_ExplicitSpecialization) {
+ // A deduction guide is not on the list of entities that can be
+ // explicitly specialized.
+ Diag(NewFD->getLocStart(), diag::err_deduction_guide_specialized)
+ << /*explicit specialization*/ 1;
}
// Find any virtual functions that this function overrides.
Modified: cfe/trunk/lib/Sema/SemaTemplate.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaTemplate.cpp?rev=294641&r1=294640&r2=294641&view=diff
==============================================================================
--- cfe/trunk/lib/Sema/SemaTemplate.cpp (original)
+++ cfe/trunk/lib/Sema/SemaTemplate.cpp Thu Feb 9 16:47:51 2017
@@ -8187,6 +8187,14 @@ DeclResult Sema::ActOnExplicitInstantiat
return true;
}
+ // A deduction guide is not on the list of entities that can be explicitly
+ // instantiated.
+ if (Name.getNameKind() == DeclarationName::CXXDeductionGuideName) {
+ Diag(D.getDeclSpec().getLocStart(), diag::err_deduction_guide_specialized)
+ << /*explicit instantiation*/ 0;
+ return true;
+ }
+
// C++0x [temp.explicit]p2:
// There are two forms of explicit instantiation: an explicit instantiation
// definition and an explicit instantiation declaration. An explicit
Modified: cfe/trunk/test/CXX/temp/temp.deduct.guide/p1.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CXX/temp/temp.deduct.guide/p1.cpp?rev=294641&r1=294640&r2=294641&view=diff
==============================================================================
--- cfe/trunk/test/CXX/temp/temp.deduct.guide/p1.cpp (original)
+++ cfe/trunk/test/CXX/temp/temp.deduct.guide/p1.cpp Thu Feb 9 16:47:51 2017
@@ -86,3 +86,23 @@ A(int(&)[43]) -> A<int> try {} catch (..
#ifdef CLASS
};
#endif
+
+namespace ExplicitInst {
+ // Explicit instantiation / specialization is not permitted.
+ template<typename T> struct B {};
+ template<typename T> B(T) -> B<T>;
+ template<> B(int) -> B<int>; // expected-error {{deduction guide cannot be explicitly specialized}}
+ extern template B(float) -> B<float>; // expected-error {{deduction guide cannot be explicitly instantiated}}
+ template B(char) -> B<char>; // expected-error {{deduction guide cannot be explicitly instantiated}}
+
+ // An attempt at partial specialization doesn't even parse as a deduction-guide.
+ template<typename T> B<T*>(T*) -> B<T*>; // expected-error 1+{{}} expected-note 0+{{}}
+
+ struct X {
+ template<typename T> struct C {};
+ template<typename T> C(T) -> C<T>;
+ template<> C(int) -> C<int>; // expected-error {{explicit specialization of '<deduction guide for C>' in class scope}}
+ extern template C(float) -> C<float>; // expected-error {{expected member name or ';'}}
+ template C(char) -> C<char>; // expected-error {{expected '<' after 'template'}}
+ };
+}
Modified: cfe/trunk/www/cxx_status.html
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/www/cxx_status.html?rev=294641&r1=294640&r2=294641&view=diff
==============================================================================
--- cfe/trunk/www/cxx_status.html (original)
+++ cfe/trunk/www/cxx_status.html Thu Feb 9 16:47:51 2017
@@ -682,10 +682,14 @@ as the draft C++1z standard evolves.
<td class="svn" align="center">Clang 4</td>
</tr>
<tr>
- <td>Template argument deduction for class templates</td>
+ <td rowspan="2">Template argument deduction for class templates</td>
<td><a href="http://wg21.link/p0091r3">P0091R3</a></td>
- <td class="none" align="center">No</td>
+ <td class="partial" align="center">Partial</td>
</tr>
+ <tr> <!-- from Issaquah -->
+ <td><a href="http://wg21.link/p0512r0">P0512R0</a></td>
+ <td class="partial" align="center">Partial</td>
+ </tr>
<tr>
<td>Non-type template parameters with <tt>auto</tt> type</td>
<td><a href="http://wg21.link/p0127r2">P0127R2</a></td>
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