Recursive calls to ValueObject::GetSummaryAsCString() are causing crashes.

The previous approach to controlling the recursion was doing it from
outside the function which is not reliable. Now it is being done inside
the function. This might not solve all of the crashes that we were seeing
since there are other functions that clear the bit that indicates that
the summary is in the process of being generated, but it might solve some.

llvm-svn: 147741

2 files changed, 28 insertions, 21 deletions

diff --git a/lldb/include/lldb/Core/ValueObject.h b/lldb/include/lldb/Core/ValueObject.h
index d119a65481c..2a93f4b13d6 100644
--- a/lldb/include/lldb/Core/ValueObject.h
+++ b/lldb/include/lldb/Core/ValueObject.h
@@ -951,7 +951,7 @@ public:
         m_forced_summary_format = format;
         m_user_id_of_forced_summary = m_update_point.GetModID();
         m_summary_str.clear();
-        m_trying_summary_already = false;
+        m_is_getting_summary = false;
     }
     
     lldb::SummaryFormatSP
@@ -987,7 +987,7 @@ public:
     {
         m_last_summary_format = format;
         m_summary_str.clear();
-        m_trying_summary_already = false;
+        m_is_getting_summary = false;
     }
     
     void
@@ -1109,7 +1109,7 @@ protected:
                         m_is_bitfield_for_scalar:1,
                         m_is_expression_path_child:1,
                         m_is_child_at_offset:1,
-                        m_trying_summary_already:1; // used to prevent endless recursion in printing summaries
+                        m_is_getting_summary:1;
     
     friend class ClangExpressionDeclMap;  // For GetValue
     friend class ClangExpressionVariable; // For SetName
diff --git a/lldb/source/Core/ValueObject.cpp b/lldb/source/Core/ValueObject.cpp
index 23d22d17257..549b40b17f9 100644
--- a/lldb/source/Core/ValueObject.cpp
+++ b/lldb/source/Core/ValueObject.cpp
@@ -95,7 +95,7 @@ ValueObject::ValueObject (ValueObject &parent) :
     m_is_bitfield_for_scalar(false),
     m_is_expression_path_child(false),
     m_is_child_at_offset(false),
-    m_trying_summary_already(false)
+    m_is_getting_summary(false)
 {
     m_manager->ManageObject(this);
 }
@@ -141,7 +141,7 @@ ValueObject::ValueObject (ExecutionContextScope *exe_scope,
     m_is_bitfield_for_scalar(false),
     m_is_expression_path_child(false),
     m_is_child_at_offset(false),
-    m_trying_summary_already(false)
+    m_is_getting_summary(false)
 {
     m_manager = new ValueObjectManager();
     m_manager->ManageObject (this);
@@ -564,6 +564,13 @@ ValueObject::CreateChildAtIndex (uint32_t idx, bool synthetic_array_member, int3
 const char *
 ValueObject::GetSummaryAsCString ()
 {
+    // Watch for recursion which can happen with summary strings and other
+    // variable formatting options.
+    if (m_is_getting_summary)
+        return NULL;
+    
+    m_is_getting_summary = true;
+
     if (UpdateValueIfNeeded (true))
     {        
         if (m_summary_str.empty())
@@ -635,6 +642,7 @@ ValueObject::GetSummaryAsCString ()
             }
         }
     }
+    m_is_getting_summary = false;
     if (m_summary_str.empty())
         return NULL;
     return m_summary_str.c_str();
@@ -1129,33 +1137,32 @@ ValueObject::GetPrintableRepresentation(Stream& s,
         case eDisplayValue:
             return_value = GetValueAsCString();
             break;
+
         case eDisplaySummary:
-            if (m_trying_summary_already)
-                return_value = NULL;
-            else
-            {
-                m_trying_summary_already = true;
-                return_value = GetSummaryAsCString();
-                m_trying_summary_already = false;
-                break;
-            }
+            return_value = GetSummaryAsCString();
+            break;
+
         case eDisplayLanguageSpecific:
             return_value = GetObjectDescription();
             break;
+
         case eDisplayLocation:
             return_value = GetLocationAsCString();
             break;
+
         case eDisplayChildrenCount:
-        {
-            alloc_mem.resize(512);
-            return_value = &alloc_mem[0];
-            int count = GetNumChildren();
-            snprintf((char*)return_value, 512, "%d", count);
+            {
+                alloc_mem.resize(512);
+                return_value = &alloc_mem[0];
+                int count = GetNumChildren();
+                snprintf((char*)return_value, 512, "%d", count);
+            }
             break;
-        }
+
         case eDisplayType:
             return_value = GetTypeName().AsCString();
             break;
+
         default:
             break;
     }
@@ -3742,7 +3749,7 @@ ValueObject::ClearUserVisibleData()
     m_value_str.clear();
     m_summary_str.clear();
     m_object_desc_str.clear();
-    m_trying_summary_already = false;
+    m_is_getting_summary = false;
 }
 
 SymbolContextScope *