diff --git a/core/org.eclipse.cdt.core/model/org/eclipse/cdt/internal/core/model/ASTStringUtil.java b/core/org.eclipse.cdt.core/model/org/eclipse/cdt/internal/core/model/ASTStringUtil.java
index 42c8c51920d..a8bb67cfdd5 100644
--- a/core/org.eclipse.cdt.core/model/org/eclipse/cdt/internal/core/model/ASTStringUtil.java
+++ b/core/org.eclipse.cdt.core/model/org/eclipse/cdt/internal/core/model/ASTStringUtil.java
@@ -79,6 +79,7 @@ import org.eclipse.cdt.core.dom.ast.cpp.ICPPASTTemplateParameter;
 import org.eclipse.cdt.core.dom.ast.cpp.ICPPASTTemplatedTypeTemplateParameter;
 import org.eclipse.cdt.core.dom.ast.cpp.ICPPASTTypeId;
 import org.eclipse.cdt.core.dom.ast.cpp.ICPPASTTypeIdExpression;
+import org.eclipse.cdt.core.dom.ast.cpp.ICPPASTTypeTransformationSpecifier;
 import org.eclipse.cdt.core.dom.ast.cpp.ICPPASTUnaryExpression;
 import org.eclipse.cdt.core.dom.ast.gnu.IGNUASTCompoundStatementExpression;
 import org.eclipse.cdt.core.dom.ast.gnu.c.ICASTKnRFunctionDeclarator;
@@ -698,6 +699,17 @@ public class ASTStringUtil {
 		} else if (declSpecifier instanceof IASTNamedTypeSpecifier) {
 			final IASTNamedTypeSpecifier namedTypeSpec = (IASTNamedTypeSpecifier) declSpecifier;
 			appendQualifiedNameString(buffer, namedTypeSpec.getName());
+		} else if (declSpecifier instanceof ICPPASTTypeTransformationSpecifier) {
+			final ICPPASTTypeTransformationSpecifier typeTransformationSpec = (ICPPASTTypeTransformationSpecifier) declSpecifier;
+			switch (typeTransformationSpec.getOperator()) {
+			case underlying_type:
+				buffer.append(GCCKeywords.cp__underlying_type);
+				break;
+			default:
+			}
+			buffer.append('(');
+			appendTypeIdString(buffer, typeTransformationSpec.getOperand());
+			buffer.append(')');
 		}
 		return buffer;
 	}
diff --git a/core/org.eclipse.cdt.core/model/org/eclipse/cdt/internal/core/model/CModelBuilder2.java b/core/org.eclipse.cdt.core/model/org/eclipse/cdt/internal/core/model/CModelBuilder2.java
index a8749c1b251..63c983b1b11 100644
--- a/core/org.eclipse.cdt.core/model/org/eclipse/cdt/internal/core/model/CModelBuilder2.java
+++ b/core/org.eclipse.cdt.core/model/org/eclipse/cdt/internal/core/model/CModelBuilder2.java
@@ -67,6 +67,7 @@ import org.eclipse.cdt.core.dom.ast.cpp.ICPPASTStaticAssertDeclaration;
 import org.eclipse.cdt.core.dom.ast.cpp.ICPPASTTemplateDeclaration;
 import org.eclipse.cdt.core.dom.ast.cpp.ICPPASTTemplateId;
 import org.eclipse.cdt.core.dom.ast.cpp.ICPPASTTemplateSpecialization;
+import org.eclipse.cdt.core.dom.ast.cpp.ICPPASTTypeTransformationSpecifier;
 import org.eclipse.cdt.core.dom.ast.cpp.ICPPASTUsingDeclaration;
 import org.eclipse.cdt.core.dom.ast.cpp.ICPPASTUsingDirective;
 import org.eclipse.cdt.core.dom.ast.cpp.ICPPASTVisibilityLabel;
@@ -491,6 +492,10 @@ public class CModelBuilder2 implements IContributedModelBuilder {
 			if (declarator != null) {
 				return createTypedefOrFunctionOrVariable(parent, declSpecifier, declarator, isTemplate);
 			}
+		} else if (declSpecifier instanceof ICPPASTTypeTransformationSpecifier) {
+			if (declarator != null) {
+				return createTypedefOrFunctionOrVariable(parent, declSpecifier, declarator, isTemplate);
+			}
 		} else {
 			assert false : "TODO: " + declSpecifier.getClass().getName(); //$NON-NLS-1$
 		}