Implement DR136
Friend declarations that specify a default argument must be a definition
and the only declaration in the translation unit.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@184889 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaDeclCXX.cpp b/lib/Sema/SemaDeclCXX.cpp
index caf7aff..4e5e307 100644
--- a/lib/Sema/SemaDeclCXX.cpp
+++ b/lib/Sema/SemaDeclCXX.cpp
@@ -404,6 +404,17 @@
}
}
+static bool functionDeclHasDefaultArgument(const FunctionDecl *FD) {
+ for (unsigned NumParams = FD->getNumParams(); NumParams > 0; --NumParams) {
+ const ParmVarDecl *PVD = FD->getParamDecl(NumParams-1);
+ if (!PVD->hasDefaultArg())
+ return false;
+ if (!PVD->hasInheritedDefaultArg())
+ return true;
+ }
+ return false;
+}
+
/// MergeCXXFunctionDecl - Merge two declarations of the same C++
/// function, once we already know that they have the same
/// type. Subroutine of MergeFunctionDecl. Returns true if there was an
@@ -578,6 +589,17 @@
Invalid = true;
}
+ // C++11 [dcl.fct.default]p4: If a friend declaration specifies a default
+ // argument expression, that declaration shall be a deļ¬nition and shall be
+ // the only declaration of the function or function template in the
+ // translation unit.
+ if (Old->getFriendObjectKind() == Decl::FOK_Undeclared &&
+ functionDeclHasDefaultArgument(Old)) {
+ Diag(New->getLocation(), diag::err_friend_decl_with_def_arg_redeclared);
+ Diag(Old->getLocation(), diag::note_previous_declaration);
+ Invalid = true;
+ }
+
if (CheckEquivalentExceptionSpec(Old, New))
Invalid = true;
@@ -11377,6 +11399,18 @@
else
FD = cast<FunctionDecl>(ND);
+ // C++11 [dcl.fct.default]p4: If a friend declaration specifies a
+ // default argument expression, that declaration shall be a definition
+ // and shall be the only declaration of the function or function
+ // template in the translation unit.
+ if (functionDeclHasDefaultArgument(FD)) {
+ if (FunctionDecl *OldFD = FD->getPreviousDecl()) {
+ Diag(FD->getLocation(), diag::err_friend_decl_with_def_arg_redeclared);
+ Diag(OldFD->getLocation(), diag::note_previous_declaration);
+ } else if (!D.isFunctionDefinition())
+ Diag(FD->getLocation(), diag::err_friend_decl_with_def_arg_must_be_def);
+ }
+
// Mark templated-scope function declarations as unsupported.
if (FD->getNumTemplateParameterLists())
FrD->setUnsupportedFriend(true);