Debugger: Try to handle empty base classes more gracefully with LLDB

Empty base classes are counted towards GetNumberOfDirectBaseClasses()
but do not get reported in GetChildCount(). Fix the difference by
manually creating empty base class entries in the report.

Change-Id: I2650d9f5234302c5bf2fa0e62a886d3a39fc11db
Reviewed-by: Christian Stenger <christian.stenger@theqtcompany.com>

share/qtcreator/debugger/lldbbridge.py

@@ -1115,21 +1115,41 @@ class Dumper(DumperBase):
                     self.putItem(child)
             return
 
-        n = value.GetNumChildren()
+        memberBase = 0  # Start of members.
-        m = value.GetType().GetNumberOfDirectBaseClasses()
+
-        if n > 10000:
+        class ChildItem:
-            n = 10000
+            def __init__(self, name, value):
-        # seems to happen in the 'inheritance' autotest
+                self.name = name
-        if m > n:
+                self.value = value
-            m = n
+
-        for i in xrange(m):
+        baseObjects = []
-            child = value.GetChildAtIndex(i)
+        for i in xrange(value.GetType().GetNumberOfDirectBaseClasses()):
+            baseClass = value.GetType().GetDirectBaseClassAtIndex(i).GetType()
+            baseChildCount = baseClass.GetNumberOfFields() \
+                + baseClass.GetNumberOfDirectBaseClasses() \
+                + baseClass.GetNumberOfVirtualBaseClasses()
+            if baseChildCount:
+                memberBase += 1
+                baseObjects.append(ChildItem(baseClass.GetName(), value.GetChildAtIndex(i)))
+            else:
+                # This base object is empty, but exists and will *not* be reported
+                # by value.GetChildCount(). So manually report the empty base class.
+                baseObject = value.Cast(baseClass)
+                baseObjects.append(ChildItem(baseClass.GetName(), baseObject))
+
+        if self.sortStructMembers:
+            baseObjects.sort(key = lambda baseObject: str(baseObject.name))
+        for i in xrange(len(baseObjects)):
+            baseObject = baseObjects[i]
             with UnnamedSubItem(self, "@%d" % (i + 1)):
                self.put('iname="%s",' % self.currentIName)
-                self.put('name="[%s]",' % child.name)
+               self.put('name="[%s]",' % baseObject.name)
-                self.putItem(child)
+               self.putItem(baseObject.value)
 
-        children = [value.GetChildAtIndex(i) for i in xrange(m, n)]
+        memberCount = value.GetNumChildren()
+        if memberCount > 10000:
+            memberCount = 10000
+        children = [value.GetChildAtIndex(memberBase + i) for i in xrange(memberCount)]
         if self.sortStructMembers:
             children.sort(key = lambda child: str(child.GetName()))
         for child in children: