From: Fariborz Jahanian <fjahanian@apple.com>
Date: Wed, 14 Oct 2009 00:52:43 +0000 (+0000)
Subject: Handle ambiguity of reference initialization.
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=d9290cb5ad9eae8d10487cea5392331cf6a47142;p=clang

Handle ambiguity of reference initialization.
Removes a FIXME.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@84068 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td
index 9e50ca65fb..5efab50ae3 100644
--- a/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/include/clang/Basic/DiagnosticSemaKinds.td
@@ -793,6 +793,8 @@ def err_ovl_builtin_unary_candidate : Note<
 def err_ovl_no_viable_function_in_init : Error<
   "no matching constructor for initialization of %0">;
 def err_ovl_ambiguous_init : Error<"call to constructor of %0 is ambiguous">;
+def err_ref_init_ambiguous : Error<
+  "reference initialization of type %0 with initializer of type %1 is ambiguous">;
 def err_ovl_deleted_init : Error<
   "call to %select{unavailable|deleted}0 constructor of %1">;
 def err_ovl_ambiguous_oper : Error<
diff --git a/lib/Sema/SemaDeclCXX.cpp b/lib/Sema/SemaDeclCXX.cpp
index 075f756bb5..acb2a67770 100644
--- a/lib/Sema/SemaDeclCXX.cpp
+++ b/lib/Sema/SemaDeclCXX.cpp
@@ -3731,7 +3731,16 @@ Sema::CheckReferenceInit(Expr *&Init, QualType DeclType,
       break;
 
     case OR_Ambiguous:
-      assert(false && "Ambiguous reference binding conversions not implemented.");
+      if (ICS) {
+        for (OverloadCandidateSet::iterator Cand = CandidateSet.begin();
+             Cand != CandidateSet.end(); ++Cand)
+          if (Cand->Viable)
+            ICS->ConversionFunctionSet.push_back(Cand->Function);
+        break;
+      }
+      Diag(DeclLoc, diag::err_ref_init_ambiguous) << DeclType << Init->getType()
+            << Init->getSourceRange();
+      PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true);
       return true;
 
     case OR_No_Viable_Function:
diff --git a/test/SemaCXX/ref-init-ambiguous.cpp b/test/SemaCXX/ref-init-ambiguous.cpp
new file mode 100644
index 0000000000..dda1ead7b6
--- /dev/null
+++ b/test/SemaCXX/ref-init-ambiguous.cpp
@@ -0,0 +1,28 @@
+// RUN: clang-cc -fsyntax-only -verify %s -std=c++0x
+
+enum E2 { };
+
+struct A { 
+  operator E2&(); // expected-note 3 {{candidate function}}
+};
+
+struct B { 
+  operator E2&(); // expected-note 3 {{candidate function}}
+};
+
+struct C : B, A { 
+};
+
+void test(C c) {
+	const E2 &e2 = c; // expected-error {{reference initialization of type 'enum E2 const &' with initializer of type 'struct C' is ambiguous}}
+}
+
+void foo(const E2 &);
+
+const E2 & re(C c) {
+    foo(c); // expected-error {{reference initialization of type 'enum E2 const &' with initializer of type 'struct C' is ambiguous}}
+
+    return c; // expected-error {{reference initialization of type 'enum E2 const &' with initializer of type 'struct C' is ambiguous}}
+}
+
+