Switch DIDescriptor to use a TrackingVH. - This makes it much safer to work with debug info, since it was extraordinarily easy to have dangling pointers thanks to MDNode uniquing.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82507 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 2 insertions, 1 deletions

diff --git a/include/llvm/Analysis/DebugInfo.h b/include/llvm/Analysis/DebugInfo.h
index f211be2d49..35f6787f02 100644
--- a/include/llvm/Analysis/DebugInfo.h
+++ b/include/llvm/Analysis/DebugInfo.h
@@ -24,6 +24,7 @@
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/SmallPtrSet.h"
 #include "llvm/Support/Dwarf.h"
+#include "llvm/Support/ValueHandle.h"
 
 namespace llvm {
   class BasicBlock;
@@ -45,7 +46,7 @@ namespace llvm {
 
   class DIDescriptor {
   protected:
-    MDNode *DbgNode;
+    TrackingVH<MDNode> DbgNode;
 
     /// DIDescriptor constructor.  If the specified node is non-null, check
     /// to make sure that the tag in the descriptor matches 'RequiredTag'.  If