Fix bug #6448: Crash with invalid anchor.

If we check whether a cursor is valid, we should also check the anchor_.

git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/branches/BRANCH_1_6_X@33281 a592a061-630c-0410-9148-cb99ea01b6c8

src/Cursor.cpp

@@ -2109,9 +2109,12 @@ Font Cursor::getFont() const
 
 bool Cursor::fixIfBroken()
 {
-	if (DocIterator::fixIfBroken()) {
-			clearSelection();
-			return true;
+	bool const broken_cursor = DocIterator::fixIfBroken();
+	bool const broken_anchor = anchor_.fixIfBroken();
+	
+	if (broken_cursor || broken_anchor) {
+		clearSelection();
+		return true;
 	}
 	return false;
 }

status.16x

@@ -120,6 +120,9 @@ What's new
 
 - Fix a crash when closing a document with a pending autocompletion popup
   (bug 6431).
+ 
+- Fix a crash when trying to select a whole empty math inset. This causes
+  the empty inset to disappear and the anchor to be invalid (bug 6448).
 
 - While in ERT, disable non-functional sub- and superscript functions that
   crashed LyX (bug 6459).