Bug 509662 - Friend function declared in header included at non-global scope

This fix is a hacky workaround. A proper fix involves fixing bug 315964.

Change-Id: I733064fe3aa0d9416854954ef3e3a8250566dac1

2 files changed, 46 insertions, 2 deletions

diff --git a/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/internal/index/tests/IndexMultiFileTest.java b/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/internal/index/tests/IndexMultiFileTest.java
index dbf8ad5df66..23d52d1aaff 100644
--- a/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/internal/index/tests/IndexMultiFileTest.java
+++ b/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/internal/index/tests/IndexMultiFileTest.java
@@ -165,6 +165,29 @@ public class IndexMultiFileTest extends IndexBindingResolutionTestBase {
 	}
 
 	// test.h
+	//	friend int operator*(double, C) { return 0; }
+	
+	// test.cpp *
+	//	namespace N {
+	//
+	//	    struct unrelated {};
+	//
+	//	    struct B {
+	//	        friend int operator*(unrelated, unrelated) { return 0; }
+	//	    };
+	//	}
+	//	    
+	//	template <typename = int>
+	//	struct C : public N::B {
+	//	    #include "test.h"
+	//	};
+	//	template <typename> struct Waldo;
+	//	Waldo<decltype(0.5 * C<>{})> w;
+	public void testFriendFunctionInHeaderIncludedAtClassScope_509662() throws Exception {
+		checkBindings();
+	}
+
+	// test.h
 	//	template <typename T>
 	//	struct atomic;
 	//
@@ -209,5 +232,4 @@ public class IndexMultiFileTest extends IndexBindingResolutionTestBase {
 		// This code is invalid, so we don't checkBindings().
 		// If the test gets this far (doesn't throw in setup() during indexing), it passes.
 	}
-
 }
diff --git a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/CPPSemantics.java b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/CPPSemantics.java
index d75ed6a77c4..14c71b4773c 100644
--- a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/CPPSemantics.java
+++ b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/CPPSemantics.java
@@ -153,6 +153,7 @@ import org.eclipse.cdt.core.dom.ast.cpp.ICPPConstructor;
 import org.eclipse.cdt.core.dom.ast.cpp.ICPPField;
 import org.eclipse.cdt.core.dom.ast.cpp.ICPPFunction;
 import org.eclipse.cdt.core.dom.ast.cpp.ICPPFunctionInstance;
+import org.eclipse.cdt.core.dom.ast.cpp.ICPPFunctionSpecialization;
 import org.eclipse.cdt.core.dom.ast.cpp.ICPPFunctionTemplate;
 import org.eclipse.cdt.core.dom.ast.cpp.ICPPFunctionType;
 import org.eclipse.cdt.core.dom.ast.cpp.ICPPMember;
@@ -3714,7 +3715,7 @@ public class CPPSemantics {
 							Object item = items[i];
 							items[i]= null;
 							if (item instanceof IIndexBinding) {
-								if (!fileSet.containsDeclaration((IIndexBinding) item)) {
+								if (!indexBindingIsReachable(fileSet, (IIndexBinding) item)) {
 									continue;
 								}
 							}
@@ -3826,6 +3827,27 @@ public class CPPSemantics {
 		return null;
     }
 
+	private static boolean indexBindingIsReachable(IIndexFileSet fileSet, IIndexBinding item) {
+		if (fileSet.containsDeclaration(item)) {
+			return true;
+		}
+
+		// Specializations of friend functions are sometimes created in the context
+		// of the file for which the AST is created, and which is thus not in the index
+		// file set. In some cases, an AST binding cannot be created for such 
+		// specializations. To support these cases, consider the binding reachable if
+		// the friend function being specialized is reachable.
+		// This situation only arises in the presence of #includes that are not at
+		// global scope. Once bug 315964 is fixed, this workaround can be removed.
+		if (item instanceof ICPPFunctionSpecialization && !(item instanceof ICPPFunctionInstance)) {
+			IBinding specialized = ((ICPPFunctionSpecialization) item).getSpecializedBinding();
+			return !(specialized instanceof IIndexBinding) 
+				|| fileSet.containsDeclaration((IIndexBinding) specialized);
+		}
+		
+		return false;
+	}
+
 	private static IBinding createSurrogateCallFunction(IScope scope, IType returnType, IType rt, IType[] parameterTypes) {
 		IType[] parms = new IType[parameterTypes.length + 1];
 		ICPPParameter[] theParms = new ICPPParameter[parms.length];