Bug 409056 - Invalid ambiguity with templated conversion operator

Change-Id: I9f56c875899ee2543aab2090387dbbdfd0e489b4
Reviewed-on: https://git.eclipse.org/r/13151
Reviewed-by: Sergey Prigogin <eclipse.sprigogin@gmail.com>
IP-Clean: Sergey Prigogin <eclipse.sprigogin@gmail.com>
Tested-by: Sergey Prigogin <eclipse.sprigogin@gmail.com>

2 files changed, 35 insertions, 2 deletions

diff --git a/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/AST2TemplateTests.java b/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/AST2TemplateTests.java
index 04a8760e4ea..163aeebf33c 100644
--- a/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/AST2TemplateTests.java
+++ b/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/AST2TemplateTests.java
@@ -125,6 +125,14 @@ public class AST2TemplateTests extends AST2TestBase {
 	private IASTTranslationUnit parseAndCheckBindings(final String code) throws Exception {
 		return parseAndCheckBindings(code, CPP);
 	}
+	
+	protected IASTTranslationUnit parseAndCheckImplicitNameBindings() throws Exception {
+		IASTTranslationUnit tu = parse(getAboveComment(), CPP, false, true, false);
+		NameCollector col = new NameCollector(true /* visit implicit names */);
+		tu.accept(col);
+		assertNoProblemBindings(col);
+		return tu;
+	}
 
 	protected BindingAssertionHelper getAssertionHelper() throws ParserException, IOException {
 		String code= getAboveComment();
@@ -7130,6 +7138,31 @@ public class AST2TemplateTests extends AST2TestBase {
 		assertNotNull(val);
 		assertEquals(0 /* false */, val.longValue());
 	}
+	
+	//	struct S {
+	//	    S(int);
+	//	};
+	//
+	//	template <typename>
+	//	struct meta {};
+	//
+	//	template <>
+	//	struct meta<S> {
+	//	    typedef void type;
+	//	};
+	//	    
+	//	struct B {
+	//	    template <typename T, typename = typename meta<T>::type>
+	//	    operator T() const;
+	//	};
+	//
+	//	struct  A {
+	//	    S waldo;
+	//	    A() : waldo(B{}) {}
+	//	};
+	public void testSFINAEInTemplatedConversionOperator_409056() throws Exception {
+		parseAndCheckImplicitNameBindings();
+	}
 
 	//	template <typename>
 	//	struct M {
diff --git a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/TemplateArgumentDeduction.java b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/TemplateArgumentDeduction.java
index 2044afbc1ee..a698a904043 100644
--- a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/TemplateArgumentDeduction.java
+++ b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/TemplateArgumentDeduction.java
@@ -370,8 +370,8 @@ public class TemplateArgumentDeduction {
 				final ICPPTemplateParameter tpar = tmplParams[i];
 				ICPPTemplateArgument deducedArg= map.getArgument(tpar);
 				if (deducedArg == null) {
-					deducedArg= tpar.getDefaultValue();
-					if (deducedArg == null)
+					deducedArg= CPPTemplates.instantiateArgument(tpar.getDefaultValue(), map, -1, null, point);
+					if (!CPPTemplates.isValidArgument(deducedArg))
 						return null;
 				}			
 				result[i]= deducedArg;