From: Douglas Gregor <dgregor@apple.com>
Date: Sat, 21 May 2011 22:16:50 +0000 (+0000)
Subject: It's considered poor form to create references to the overloaded
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=9625e44c0252485277a340746ed8ac950686156f;p=clang

It's considered poor form to create references to the overloaded
function type. Educate template argument deduction thusly, fixing
PR9974 / <rdar://problem/9479155>.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@131811 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/AST/ASTContext.cpp b/lib/AST/ASTContext.cpp
index b0303797e4..e664855067 100644
--- a/lib/AST/ASTContext.cpp
+++ b/lib/AST/ASTContext.cpp
@@ -1423,6 +1423,9 @@ QualType ASTContext::getBlockPointerType(QualType T) const {
 /// lvalue reference to the specified type.
 QualType
 ASTContext::getLValueReferenceType(QualType T, bool SpelledAsLValue) const {
+  assert(getCanonicalType(T) != OverloadTy && 
+         "Unresolved overloaded function type");
+  
   // Unique pointers, to guarantee there is only one pointer of a particular
   // structure.
   llvm::FoldingSetNodeID ID;
diff --git a/lib/Sema/SemaTemplateDeduction.cpp b/lib/Sema/SemaTemplateDeduction.cpp
index 235af049cf..f2ec09b132 100644
--- a/lib/Sema/SemaTemplateDeduction.cpp
+++ b/lib/Sema/SemaTemplateDeduction.cpp
@@ -2507,7 +2507,9 @@ static bool AdjustFunctionParmAndArgTypesForDeduction(Sema &S,
     if (isa<RValueReferenceType>(ParamType)) {
       if (!PointeeType.getQualifiers() &&
           isa<TemplateTypeParmType>(PointeeType) &&
-          Arg->Classify(S.Context).isLValue())
+          Arg->Classify(S.Context).isLValue() &&
+          Arg->getType() != S.Context.OverloadTy &&
+          Arg->getType() != S.Context.BoundMemberTy)
         ArgType = S.Context.getLValueReferenceType(ArgType);
     }
 
diff --git a/lib/Sema/SemaType.cpp b/lib/Sema/SemaType.cpp
index dbacb47812..884144f99b 100644
--- a/lib/Sema/SemaType.cpp
+++ b/lib/Sema/SemaType.cpp
@@ -1071,6 +1071,9 @@ QualType Sema::BuildPointerType(QualType T,
 QualType Sema::BuildReferenceType(QualType T, bool SpelledAsLValue,
                                   SourceLocation Loc,
                                   DeclarationName Entity) {
+  assert(Context.getCanonicalType(T) != Context.OverloadTy && 
+         "Unresolved overloaded function type");
+  
   // C++0x [dcl.ref]p6:
   //   If a typedef (7.1.3), a type template-parameter (14.3.1), or a 
   //   decltype-specifier (7.1.6.2) denotes a type TR that is a reference to a 
diff --git a/test/CXX/stmt.stmt/stmt.iter/stmt.ranged/p1.cpp b/test/CXX/stmt.stmt/stmt.iter/stmt.ranged/p1.cpp
index 12acde143c..7bfa6fe582 100644
--- a/test/CXX/stmt.stmt/stmt.iter/stmt.ranged/p1.cpp
+++ b/test/CXX/stmt.stmt/stmt.iter/stmt.ranged/p1.cpp
@@ -33,8 +33,8 @@ struct B {
   int *alt_end();
 };
 
-void f(); // expected-note {{candidate}}
-void f(int); // expected-note {{candidate}}
+void f();
+void f(int);
 
 void g() {
   for (int a : A())
@@ -44,7 +44,7 @@ void g() {
   for (char *a : B()) { // expected-error {{cannot initialize a variable of type 'char *' with an lvalue of type 'int'}}
   }
   // FIXME: Terrible diagnostic here. auto deduction should fail, but does not!
-  for (double a : f) { // expected-error {{address of overloaded function 'f' does not match required type '<overloaded function type>'}}
+  for (double a : f) { // expected-error {{cannot use type '<overloaded function type>' as a range}}
   }
   for (auto a : A()) {
   }
diff --git a/test/SemaTemplate/deduction-crash.cpp b/test/SemaTemplate/deduction-crash.cpp
index ec97311e5d..fb23eda5bb 100644
--- a/test/SemaTemplate/deduction-crash.cpp
+++ b/test/SemaTemplate/deduction-crash.cpp
@@ -1,10 +1,10 @@
 // RUN: %clang_cc1 -fsyntax-only %s 2>&1| FileCheck %s
 
-// PR7511
-
 // Note that the error count below doesn't matter. We just want to
 // make sure that the parser doesn't crash.
-// CHECK: 13 errors
+// CHECK: 14 errors
+
+// PR7511
 template<a>
 struct int_;
 
@@ -57,3 +57,33 @@ int a()
   state_machine<int> p;
   p.ant(0);
 }
+
+// PR9974
+template <int> struct enable_if;
+template <class > struct remove_reference ;
+template <class _Tp> struct remove_reference<_Tp&> ;
+
+template <class > struct __tuple_like;
+
+template <class _Tp, class _Up, int = __tuple_like<typename remove_reference<_Tp>::type>::value> 
+struct __tuple_convertible;
+
+struct pair
+{
+template<class _Tuple, int = enable_if<__tuple_convertible<_Tuple, pair>::value>::type> 
+pair(_Tuple&& );
+};
+
+template <class> struct basic_ostream;
+
+template <int> 
+void endl( ) ;
+
+extern basic_ostream<char> cout;
+
+int operator<<( basic_ostream<char> , pair ) ;
+
+void register_object_imp ( )
+{
+cout << endl<1>;
+}