Fixed bug in FoldingSetIteratorImpl where we did not correctly check if

we had reached the "fake bucket" after the last bucket, allowing the iterator
in some cases to run off the end of the hashtable.

llvm-svn: 47178

1 files changed, 4 insertions, 2 deletions

diff --git a/llvm/lib/Support/FoldingSet.cpp b/llvm/lib/Support/FoldingSet.cpp
index 2d2279cefe5..97d1f0d1689 100644
--- a/llvm/lib/Support/FoldingSet.cpp
+++ b/llvm/lib/Support/FoldingSet.cpp
@@ -326,7 +326,8 @@ FoldingSetImpl::Node *FoldingSetImpl::GetOrInsertNode(FoldingSetImpl::Node *N) {
 
 FoldingSetIteratorImpl::FoldingSetIteratorImpl(void **Bucket) {
   // Skip to the first non-null non-self-cycle bucket.
-  while (*Bucket == 0 || GetNextPtr(*Bucket) == 0)
+  while (*Bucket != reinterpret_cast<void*>(-1) &&
+         (*Bucket == 0 || GetNextPtr(*Bucket) == 0))
     ++Bucket;
   
   NodePtr = static_cast<FoldingSetNode*>(*Bucket);
@@ -345,7 +346,8 @@ void FoldingSetIteratorImpl::advance() {
     // Skip to the next non-null non-self-cycle bucket.
     do {
       ++Bucket;
-    } while (*Bucket == 0 || GetNextPtr(*Bucket) == 0);
+    } while (*Bucket != reinterpret_cast<void*>(-1) &&
+             (*Bucket == 0 || GetNextPtr(*Bucket) == 0));
     
     NodePtr = static_cast<FoldingSetNode*>(*Bucket);
   }