From ed28b6d0280d49da5d3d69ed823e812dcbc2798b Mon Sep 17 00:00:00 2001
From: Ted Kremenek <kremenek@apple.com>
Date: Fri, 22 May 2009 22:03:22 +0000
Subject: [PATCH] Modify begin()/end() for AsmStmt iterators to handle the case
 when Exprs.empty() is true. Because of recent changes to llvm::SmallVector,
 using these iterators when Exprs was empty would cause an assertion failure.

This fixes: PR 4245.

llvm-svn: 72286
---
 clang/include/clang/AST/Stmt.h | 25 +++++++++++++++++--------
 1 file changed, 17 insertions(+), 8 deletions(-)

diff --git a/clang/include/clang/AST/Stmt.h b/clang/include/clang/AST/Stmt.h
index 57b420870fff..ffd2a742df3a 100644
--- a/clang/include/clang/AST/Stmt.h
+++ b/clang/include/clang/AST/Stmt.h
@@ -1161,30 +1161,39 @@ public:
   typedef ConstExprIterator const_inputs_iterator;
   
   inputs_iterator begin_inputs() {
-    return &Exprs[0] + NumOutputs;
+    return Exprs.empty() ? NULL : &Exprs[0] + NumOutputs;
   }
   
   inputs_iterator end_inputs() {
-    return  &Exprs[0] + NumOutputs + NumInputs;
+    return Exprs.empty() ? NULL : &Exprs[0] + NumOutputs + NumInputs;
   }
   
   const_inputs_iterator begin_inputs() const {
-    return &Exprs[0] + NumOutputs;
+    return Exprs.empty() ? NULL : &Exprs[0] + NumOutputs;
   }
   
   const_inputs_iterator end_inputs() const {
-    return  &Exprs[0] + NumOutputs + NumInputs;}
+    return Exprs.empty() ? NULL : &Exprs[0] + NumOutputs + NumInputs;
+  }
   
   // Output expr iterators.
   
   typedef ExprIterator outputs_iterator;
   typedef ConstExprIterator const_outputs_iterator;
   
-  outputs_iterator begin_outputs() { return &Exprs[0]; }
-  outputs_iterator end_outputs() { return &Exprs[0] + NumOutputs; }
+  outputs_iterator begin_outputs() {
+    return Exprs.empty() ? NULL : &Exprs[0];
+  }
+  outputs_iterator end_outputs() {
+    return Exprs.empty() ? NULL : &Exprs[0] + NumOutputs;
+  }
   
-  const_outputs_iterator begin_outputs() const { return &Exprs[0]; }
-  const_outputs_iterator end_outputs() const { return &Exprs[0] + NumOutputs; }
+  const_outputs_iterator begin_outputs() const {
+    return Exprs.empty() ? NULL : &Exprs[0];
+  }
+  const_outputs_iterator end_outputs() const {
+    return Exprs.empty() ? NULL : &Exprs[0] + NumOutputs;
+  }
   
   // Input name iterator.