From ae8b4e25da919d069db7b595c9fc9741ffa62f86 Mon Sep 17 00:00:00 2001
From: Nathan Ridge <zeratul976@hotmail.com>
Date: Thu, 8 Feb 2018 23:40:47 -0500
Subject: [PATCH] Bug 519091 - Do not bypass the caching mechanism for class
 member specializations

Direct calls to CPPTemplates.createSpecialization() bypass the caching
mechanism, resulting in the violation of invariants such as every
binding being represented by a unique (AST-derived) binding object.

ICPPClassSpecialization.specializeMember() should be used instead.

Change-Id: I10ddb06d087d97cf05c6bed0d9f14a15440b87fe
---
 .../tests/IndexCPPTemplateResolutionTest.java | 31 +++++++++++++++++++
 .../parser/cpp/semantics/CPPTemplates.java    | 10 ++++++
 .../parser/cpp/semantics/EvalFunctionSet.java |  4 +--
 .../cpp/semantics/EvalMemberAccess.java       |  2 +-
 .../parser/cpp/semantics/ExecDeclarator.java  | 13 ++++++--
 .../cpp/semantics/ExecRangeBasedFor.java      | 17 +++++++---
 6 files changed, 68 insertions(+), 9 deletions(-)

diff --git a/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/internal/index/tests/IndexCPPTemplateResolutionTest.java b/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/internal/index/tests/IndexCPPTemplateResolutionTest.java
index f172faccb84..c5c65d39bfa 100644
--- a/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/internal/index/tests/IndexCPPTemplateResolutionTest.java
+++ b/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/internal/index/tests/IndexCPPTemplateResolutionTest.java
@@ -3167,4 +3167,35 @@ public class IndexCPPTemplateResolutionTest extends IndexBindingResolutionTestBa
 	public void testSpecializationOfAnonymousClass_528456() throws Exception {
 		checkBindings();
 	}
+	
+	//	// empty file
+	
+	//	namespace std {
+	//	    template <class E>
+	//	    struct initializer_list {
+	//	        const E* array;
+	//	        int len;
+	//	        constexpr const E* begin() const { return array; }
+	//	        constexpr const E* end() const { return array + len; }
+	//	    };
+	//	}
+	//	template <typename Enum>
+	//	struct QFlags {
+	//	    int i;
+	//	    constexpr QFlags(std::initializer_list<Enum> flags)
+	//	         : i(initializer_list_helper(flags.begin(), flags.end())) {}
+	//	    constexpr static int initializer_list_helper(const Enum* it, const Enum* end) {
+	//	        return it == end ? 0 : (int(*it) | initializer_list_helper(it + 1, end));
+	//	    }
+	//	};
+	//	enum Option {
+	//	    ShowMessageBox = 0x02,
+	//	    Log = 0x04
+	//	};
+	//	struct MessageFunctionPrivate {
+	//	    QFlags<Option> Options{ShowMessageBox, Log};
+	//	};
+	public void testConstexprInitListConstructor_519091() throws Exception {
+		checkBindings();
+	}
 }
diff --git a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/CPPTemplates.java b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/CPPTemplates.java
index 3ac22c11d96..845a3256fdb 100644
--- a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/CPPTemplates.java
+++ b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/CPPTemplates.java
@@ -978,6 +978,16 @@ public class CPPTemplates {
 		return newVariable;
 	}
 
+	/**
+	 * IMPORTANT: Do NOT call this method directly, at least when (owner instanceof ICPPClassSpecialization).
+	 *            Use ICPPClassSpecialization.specializeMember(decl) instead.
+	 *            
+	 *            This ensures that the caching mechanism for member specializations implemented by
+	 *            ICPPClassSpecialization.specializeMember() is not bypassed.
+	 *            
+	 * TODO: Implement a caching mechanism for non-class owners, too, and make specializeMember()
+	 *       a method of ICPPSpecialization itself.
+	 */
 	public static IBinding createSpecialization(ICPPSpecialization owner, IBinding decl) {
 		IBinding spec = null;
 		final ICPPTemplateParameterMap tpMap= owner.getTemplateParameterMap();
diff --git a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/EvalFunctionSet.java b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/EvalFunctionSet.java
index cef11e192a3..44c0bc953a9 100644
--- a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/EvalFunctionSet.java
+++ b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/EvalFunctionSet.java
@@ -264,10 +264,10 @@ public class EvalFunctionSet extends CPPDependentEvaluation {
 		ICPPFunction[] originalFunctions = fFunctionSet.getBindings();
 		ICPPFunction[] functions = originalFunctions;
 		if (owner instanceof ICPPClassSpecialization && owner != originalOwner) {
+			ICPPClassSpecialization ownerClass = (ICPPClassSpecialization) owner;
 			functions = new ICPPFunction[originalFunctions.length];
 			for (int i = 0; i < originalFunctions.length; i++) {
-				functions[i] = (ICPPFunction) CPPTemplates.createSpecialization((ICPPClassSpecialization) owner,
-						originalFunctions[i]);
+				functions[i] = (ICPPFunction) ownerClass.specializeMember(originalFunctions[i]); 
 			}
 		}
 		// No need to instantiate the implied object type. An EvalFunctioNSet should only be created
diff --git a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/EvalMemberAccess.java b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/EvalMemberAccess.java
index 6e49cc6b1d0..af5622c8d36 100644
--- a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/EvalMemberAccess.java
+++ b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/EvalMemberAccess.java
@@ -388,7 +388,7 @@ public class EvalMemberAccess extends CPPDependentEvaluation {
 		IBinding member = fMember;
 		IType ownerClass = SemanticUtil.getNestedType(ownerType, ALLCVQ);
 		if (ownerClass instanceof ICPPClassSpecialization) {
-			member = CPPTemplates.createSpecialization((ICPPClassSpecialization) ownerClass, fMember);
+			member = ((ICPPClassSpecialization) ownerClass).specializeMember(fMember);
 		}
 		ICPPEvaluation ownerEval = fOwnerEval;
 		if (ownerEval != null) {
diff --git a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/ExecDeclarator.java b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/ExecDeclarator.java
index 63d40248ec5..dcddf9ac317 100644
--- a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/ExecDeclarator.java
+++ b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/ExecDeclarator.java
@@ -20,8 +20,10 @@ import org.eclipse.cdt.core.dom.ast.IQualifierType;
 import org.eclipse.cdt.core.dom.ast.IType;
 import org.eclipse.cdt.core.dom.ast.IValue;
 import org.eclipse.cdt.core.dom.ast.cpp.ICPPBinding;
+import org.eclipse.cdt.core.dom.ast.cpp.ICPPClassSpecialization;
 import org.eclipse.cdt.core.dom.ast.cpp.ICPPClassType;
 import org.eclipse.cdt.core.dom.ast.cpp.ICPPReferenceType;
+import org.eclipse.cdt.core.dom.ast.cpp.ICPPSpecialization;
 import org.eclipse.cdt.core.dom.ast.cpp.ICPPVariable;
 import org.eclipse.cdt.internal.core.dom.parser.CompositeValue;
 import org.eclipse.cdt.internal.core.dom.parser.ITypeMarshalBuffer;
@@ -222,8 +224,15 @@ public final class ExecDeclarator implements ICPPExecution {
 			ICPPVariable declaredVariable = (ICPPVariable) declaredBinding;
 			newDeclaredBinding = CPPTemplates.createVariableSpecialization(context, declaredVariable);
 		} else {
-			newDeclaredBinding = (ICPPBinding) CPPTemplates.createSpecialization(
-					context.getContextSpecialization(), declaredBinding);
+			ICPPSpecialization owner = context.getContextSpecialization();
+			if (owner instanceof ICPPClassSpecialization) {
+				newDeclaredBinding = (ICPPBinding) 
+						((ICPPClassSpecialization) owner).specializeMember(declaredBinding);
+			} else {
+				// TODO: Non-class owners should also have a specializeMember() function which
+				//       implements a caching mechanism.
+				newDeclaredBinding = (ICPPBinding) CPPTemplates.createSpecialization(owner, declaredBinding);
+			}
 		}
 
 		ICPPEvaluation newInitializerEval =
diff --git a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/ExecRangeBasedFor.java b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/ExecRangeBasedFor.java
index 863fd7b218b..53de3ded8bb 100644
--- a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/ExecRangeBasedFor.java
+++ b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/ExecRangeBasedFor.java
@@ -20,10 +20,12 @@ import org.eclipse.cdt.core.dom.ast.IBinding;
 import org.eclipse.cdt.core.dom.ast.IType;
 import org.eclipse.cdt.core.dom.ast.IVariable;
 import org.eclipse.cdt.core.dom.ast.cpp.ICPPASTUnaryExpression;
+import org.eclipse.cdt.core.dom.ast.cpp.ICPPClassSpecialization;
 import org.eclipse.cdt.core.dom.ast.cpp.ICPPClassType;
 import org.eclipse.cdt.core.dom.ast.cpp.ICPPFunction;
 import org.eclipse.cdt.core.dom.ast.cpp.ICPPMethod;
 import org.eclipse.cdt.core.dom.ast.cpp.ICPPReferenceType;
+import org.eclipse.cdt.core.dom.ast.cpp.ICPPSpecialization;
 import org.eclipse.cdt.internal.core.dom.parser.ITypeMarshalBuffer;
 import org.eclipse.cdt.internal.core.dom.parser.cpp.ICPPEvaluation;
 import org.eclipse.cdt.internal.core.dom.parser.cpp.ICPPEvaluation.ConstexprEvaluationContext;
@@ -167,10 +169,17 @@ public class ExecRangeBasedFor implements ICPPExecution {
 		//       Alternatively, we could lower the range-based for loop into a regular for loop as
 		//       described in the standard (by constructing the corresponding executions and evaluations),
 		//       and the above instantiations will fall out of that automatically.
-		ICPPFunction newBegin = begin != null ? (ICPPFunction)CPPTemplates.createSpecialization(
-				context.getContextSpecialization(), begin) : null;
-		ICPPFunction newEnd = end != null ? (ICPPFunction)CPPTemplates.createSpecialization(
-				context.getContextSpecialization(), end) : null;
+		ICPPSpecialization owner = context.getContextSpecialization();
+		ICPPFunction newBegin = null;
+		ICPPFunction newEnd = null;
+		if (owner instanceof ICPPClassSpecialization) {
+			if (begin != null) {
+				newBegin = (ICPPFunction) ((ICPPClassSpecialization) owner).specializeMember(begin);
+			}
+			if (end != null) {
+				newEnd = (ICPPFunction) ((ICPPClassSpecialization) owner).specializeMember(end);
+			}
+		}
 		ICPPExecution newBodyExec = bodyExec.instantiate(context, maxDepth);
 
 		if (newDeclarationExec == declarationExec &&