diff --git a/core/org.eclipse.cdt.core/src/org/eclipse/cdt/internal/formatter/CodeFormatterVisitor.java b/core/org.eclipse.cdt.core/src/org/eclipse/cdt/internal/formatter/CodeFormatterVisitor.java
index be84be0c059..7eee8ee0cf5 100644
--- a/core/org.eclipse.cdt.core/src/org/eclipse/cdt/internal/formatter/CodeFormatterVisitor.java
+++ b/core/org.eclipse.cdt.core/src/org/eclipse/cdt/internal/formatter/CodeFormatterVisitor.java
@@ -4932,15 +4932,15 @@ public class CodeFormatterVisitor extends ASTVisitor implements ICPPASTVisitor,
 	 * Collect source positions of no-format sections in the given translation unit.
 	 *
 	 * @param translationUnit  the {@link IASTTranslationUnit}, may be <code>null</code>
-	 * @return a {@link List} of {@link Position}s
+	 * @return a modifiable {@link List} of {@link Position}s
 	 */
 	private List<InactivePosition> collectNoFormatCodePositions(IASTTranslationUnit translationUnit) {
 		if (translationUnit == null || !this.preferences.use_fomatter_comment_tag) {
-			return Collections.emptyList();
+			return new ArrayList<>();
 		}
 		String fileName = translationUnit.getFilePath();
 		if (fileName == null) {
-			return Collections.emptyList();
+			return new ArrayList<>();
 		}
 		List<InactivePosition> positions = new ArrayList<>();
 		int inactiveCodeStart = -1;
diff --git a/core/org.eclipse.cdt.ui.tests/ui/org/eclipse/cdt/ui/tests/text/CodeFormatterTest.java b/core/org.eclipse.cdt.ui.tests/ui/org/eclipse/cdt/ui/tests/text/CodeFormatterTest.java
index 57fe21a33df..d5a7504ae16 100644
--- a/core/org.eclipse.cdt.ui.tests/ui/org/eclipse/cdt/ui/tests/text/CodeFormatterTest.java
+++ b/core/org.eclipse.cdt.ui.tests/ui/org/eclipse/cdt/ui/tests/text/CodeFormatterTest.java
@@ -4803,4 +4803,18 @@ public class CodeFormatterTest extends BaseUITestCase {
 	public void testLambdaWithoutParens_Bug564273() throws Exception {
 		assertFormatterResult();
 	}
+
+	//#ifdef AAA
+	//#define BBB
+	//#endif
+
+	//#ifdef AAA
+	//#define BBB
+	//#endif
+	public void testCodeFormatterTagsOff_Bug579261() throws Exception {
+		// Tests that when there is an inactive block of code that code formatter doesn't fail when
+		// tags are disabled
+		fOptions.put(DefaultCodeFormatterConstants.FORMATTER_USE_COMMENT_TAG, DefaultCodeFormatterConstants.FALSE);
+		assertFormatterResult();
+	}
 }